1//===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// Implements semantic analysis for C++ expressions.
11///
12//===----------------------------------------------------------------------===//
13
14#include "TreeTransform.h"
15#include "TypeLocBuilder.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTLambda.h"
18#include "clang/AST/CXXInheritance.h"
19#include "clang/AST/CharUnits.h"
20#include "clang/AST/DeclObjC.h"
21#include "clang/AST/ExprCXX.h"
22#include "clang/AST/ExprConcepts.h"
23#include "clang/AST/ExprObjC.h"
24#include "clang/AST/RecursiveASTVisitor.h"
25#include "clang/AST/Type.h"
26#include "clang/AST/TypeLoc.h"
27#include "clang/Basic/AlignedAllocation.h"
28#include "clang/Basic/DiagnosticSema.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/TargetInfo.h"
31#include "clang/Basic/TokenKinds.h"
32#include "clang/Basic/TypeTraits.h"
33#include "clang/Lex/Preprocessor.h"
34#include "clang/Sema/DeclSpec.h"
35#include "clang/Sema/EnterExpressionEvaluationContext.h"
36#include "clang/Sema/Initialization.h"
37#include "clang/Sema/Lookup.h"
38#include "clang/Sema/ParsedTemplate.h"
39#include "clang/Sema/Scope.h"
40#include "clang/Sema/ScopeInfo.h"
41#include "clang/Sema/SemaCUDA.h"
42#include "clang/Sema/SemaInternal.h"
43#include "clang/Sema/SemaLambda.h"
44#include "clang/Sema/SemaObjC.h"
45#include "clang/Sema/SemaPPC.h"
46#include "clang/Sema/Template.h"
47#include "clang/Sema/TemplateDeduction.h"
48#include "llvm/ADT/APInt.h"
49#include "llvm/ADT/STLExtras.h"
50#include "llvm/ADT/STLForwardCompat.h"
51#include "llvm/ADT/StringExtras.h"
52#include "llvm/Support/ErrorHandling.h"
53#include "llvm/Support/TypeSize.h"
54#include <optional>
55using namespace clang;
56using namespace sema;
57
58ParsedType Sema::getInheritingConstructorName(CXXScopeSpec &SS,
59 SourceLocation NameLoc,
60 const IdentifierInfo &Name) {
61 NestedNameSpecifier *NNS = SS.getScopeRep();
62
63 // Convert the nested-name-specifier into a type.
64 QualType Type;
65 switch (NNS->getKind()) {
66 case NestedNameSpecifier::TypeSpec:
67 case NestedNameSpecifier::TypeSpecWithTemplate:
68 Type = QualType(NNS->getAsType(), 0);
69 break;
70
71 case NestedNameSpecifier::Identifier:
72 // Strip off the last layer of the nested-name-specifier and build a
73 // typename type for it.
74 assert(NNS->getAsIdentifier() == &Name && "not a constructor name");
75 Type = Context.getDependentNameType(
76 Keyword: ElaboratedTypeKeyword::None, NNS: NNS->getPrefix(), Name: NNS->getAsIdentifier());
77 break;
78
79 case NestedNameSpecifier::Global:
80 case NestedNameSpecifier::Super:
81 case NestedNameSpecifier::Namespace:
82 case NestedNameSpecifier::NamespaceAlias:
83 llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
84 }
85
86 // This reference to the type is located entirely at the location of the
87 // final identifier in the qualified-id.
88 return CreateParsedType(T: Type,
89 TInfo: Context.getTrivialTypeSourceInfo(T: Type, Loc: NameLoc));
90}
91
92ParsedType Sema::getConstructorName(const IdentifierInfo &II,
93 SourceLocation NameLoc, Scope *S,
94 CXXScopeSpec &SS, bool EnteringContext) {
95 CXXRecordDecl *CurClass = getCurrentClass(S, SS: &SS);
96 assert(CurClass && &II == CurClass->getIdentifier() &&
97 "not a constructor name");
98
99 // When naming a constructor as a member of a dependent context (eg, in a
100 // friend declaration or an inherited constructor declaration), form an
101 // unresolved "typename" type.
102 if (CurClass->isDependentContext() && !EnteringContext && SS.getScopeRep()) {
103 QualType T = Context.getDependentNameType(Keyword: ElaboratedTypeKeyword::None,
104 NNS: SS.getScopeRep(), Name: &II);
105 return ParsedType::make(P: T);
106 }
107
108 if (SS.isNotEmpty() && RequireCompleteDeclContext(SS, DC: CurClass))
109 return ParsedType();
110
111 // Find the injected-class-name declaration. Note that we make no attempt to
112 // diagnose cases where the injected-class-name is shadowed: the only
113 // declaration that can validly shadow the injected-class-name is a
114 // non-static data member, and if the class contains both a non-static data
115 // member and a constructor then it is ill-formed (we check that in
116 // CheckCompletedCXXClass).
117 CXXRecordDecl *InjectedClassName = nullptr;
118 for (NamedDecl *ND : CurClass->lookup(Name: &II)) {
119 auto *RD = dyn_cast<CXXRecordDecl>(Val: ND);
120 if (RD && RD->isInjectedClassName()) {
121 InjectedClassName = RD;
122 break;
123 }
124 }
125 if (!InjectedClassName) {
126 if (!CurClass->isInvalidDecl()) {
127 // FIXME: RequireCompleteDeclContext doesn't check dependent contexts
128 // properly. Work around it here for now.
129 Diag(Loc: SS.getLastQualifierNameLoc(),
130 DiagID: diag::err_incomplete_nested_name_spec) << CurClass << SS.getRange();
131 }
132 return ParsedType();
133 }
134
135 QualType T = Context.getTypeDeclType(Decl: InjectedClassName);
136 DiagnoseUseOfDecl(D: InjectedClassName, Locs: NameLoc);
137 MarkAnyDeclReferenced(Loc: NameLoc, D: InjectedClassName, /*OdrUse=*/MightBeOdrUse: false);
138
139 return ParsedType::make(P: T);
140}
141
142ParsedType Sema::getDestructorName(const IdentifierInfo &II,
143 SourceLocation NameLoc, Scope *S,
144 CXXScopeSpec &SS, ParsedType ObjectTypePtr,
145 bool EnteringContext) {
146 // Determine where to perform name lookup.
147
148 // FIXME: This area of the standard is very messy, and the current
149 // wording is rather unclear about which scopes we search for the
150 // destructor name; see core issues 399 and 555. Issue 399 in
151 // particular shows where the current description of destructor name
152 // lookup is completely out of line with existing practice, e.g.,
153 // this appears to be ill-formed:
154 //
155 // namespace N {
156 // template <typename T> struct S {
157 // ~S();
158 // };
159 // }
160 //
161 // void f(N::S<int>* s) {
162 // s->N::S<int>::~S();
163 // }
164 //
165 // See also PR6358 and PR6359.
166 //
167 // For now, we accept all the cases in which the name given could plausibly
168 // be interpreted as a correct destructor name, issuing off-by-default
169 // extension diagnostics on the cases that don't strictly conform to the
170 // C++20 rules. This basically means we always consider looking in the
171 // nested-name-specifier prefix, the complete nested-name-specifier, and
172 // the scope, and accept if we find the expected type in any of the three
173 // places.
174
175 if (SS.isInvalid())
176 return nullptr;
177
178 // Whether we've failed with a diagnostic already.
179 bool Failed = false;
180
181 llvm::SmallVector<NamedDecl*, 8> FoundDecls;
182 llvm::SmallPtrSet<CanonicalDeclPtr<Decl>, 8> FoundDeclSet;
183
184 // If we have an object type, it's because we are in a
185 // pseudo-destructor-expression or a member access expression, and
186 // we know what type we're looking for.
187 QualType SearchType =
188 ObjectTypePtr ? GetTypeFromParser(Ty: ObjectTypePtr) : QualType();
189
190 auto CheckLookupResult = [&](LookupResult &Found) -> ParsedType {
191 auto IsAcceptableResult = [&](NamedDecl *D) -> bool {
192 auto *Type = dyn_cast<TypeDecl>(Val: D->getUnderlyingDecl());
193 if (!Type)
194 return false;
195
196 if (SearchType.isNull() || SearchType->isDependentType())
197 return true;
198
199 QualType T = Context.getTypeDeclType(Decl: Type);
200 return Context.hasSameUnqualifiedType(T1: T, T2: SearchType);
201 };
202
203 unsigned NumAcceptableResults = 0;
204 for (NamedDecl *D : Found) {
205 if (IsAcceptableResult(D))
206 ++NumAcceptableResults;
207
208 // Don't list a class twice in the lookup failure diagnostic if it's
209 // found by both its injected-class-name and by the name in the enclosing
210 // scope.
211 if (auto *RD = dyn_cast<CXXRecordDecl>(Val: D))
212 if (RD->isInjectedClassName())
213 D = cast<NamedDecl>(Val: RD->getParent());
214
215 if (FoundDeclSet.insert(Ptr: D).second)
216 FoundDecls.push_back(Elt: D);
217 }
218
219 // As an extension, attempt to "fix" an ambiguity by erasing all non-type
220 // results, and all non-matching results if we have a search type. It's not
221 // clear what the right behavior is if destructor lookup hits an ambiguity,
222 // but other compilers do generally accept at least some kinds of
223 // ambiguity.
224 if (Found.isAmbiguous() && NumAcceptableResults == 1) {
225 Diag(Loc: NameLoc, DiagID: diag::ext_dtor_name_ambiguous);
226 LookupResult::Filter F = Found.makeFilter();
227 while (F.hasNext()) {
228 NamedDecl *D = F.next();
229 if (auto *TD = dyn_cast<TypeDecl>(Val: D->getUnderlyingDecl()))
230 Diag(Loc: D->getLocation(), DiagID: diag::note_destructor_type_here)
231 << Context.getTypeDeclType(Decl: TD);
232 else
233 Diag(Loc: D->getLocation(), DiagID: diag::note_destructor_nontype_here);
234
235 if (!IsAcceptableResult(D))
236 F.erase();
237 }
238 F.done();
239 }
240
241 if (Found.isAmbiguous())
242 Failed = true;
243
244 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
245 if (IsAcceptableResult(Type)) {
246 QualType T = Context.getTypeDeclType(Decl: Type);
247 MarkAnyDeclReferenced(Loc: Type->getLocation(), D: Type, /*OdrUse=*/MightBeOdrUse: false);
248 return CreateParsedType(
249 T: Context.getElaboratedType(Keyword: ElaboratedTypeKeyword::None, NNS: nullptr, NamedType: T),
250 TInfo: Context.getTrivialTypeSourceInfo(T, Loc: NameLoc));
251 }
252 }
253
254 return nullptr;
255 };
256
257 bool IsDependent = false;
258
259 auto LookupInObjectType = [&]() -> ParsedType {
260 if (Failed || SearchType.isNull())
261 return nullptr;
262
263 IsDependent |= SearchType->isDependentType();
264
265 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
266 DeclContext *LookupCtx = computeDeclContext(T: SearchType);
267 if (!LookupCtx)
268 return nullptr;
269 LookupQualifiedName(R&: Found, LookupCtx);
270 return CheckLookupResult(Found);
271 };
272
273 auto LookupInNestedNameSpec = [&](CXXScopeSpec &LookupSS) -> ParsedType {
274 if (Failed)
275 return nullptr;
276
277 IsDependent |= isDependentScopeSpecifier(SS: LookupSS);
278 DeclContext *LookupCtx = computeDeclContext(SS: LookupSS, EnteringContext);
279 if (!LookupCtx)
280 return nullptr;
281
282 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
283 if (RequireCompleteDeclContext(SS&: LookupSS, DC: LookupCtx)) {
284 Failed = true;
285 return nullptr;
286 }
287 LookupQualifiedName(R&: Found, LookupCtx);
288 return CheckLookupResult(Found);
289 };
290
291 auto LookupInScope = [&]() -> ParsedType {
292 if (Failed || !S)
293 return nullptr;
294
295 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
296 LookupName(R&: Found, S);
297 return CheckLookupResult(Found);
298 };
299
300 // C++2a [basic.lookup.qual]p6:
301 // In a qualified-id of the form
302 //
303 // nested-name-specifier[opt] type-name :: ~ type-name
304 //
305 // the second type-name is looked up in the same scope as the first.
306 //
307 // We interpret this as meaning that if you do a dual-scope lookup for the
308 // first name, you also do a dual-scope lookup for the second name, per
309 // C++ [basic.lookup.classref]p4:
310 //
311 // If the id-expression in a class member access is a qualified-id of the
312 // form
313 //
314 // class-name-or-namespace-name :: ...
315 //
316 // the class-name-or-namespace-name following the . or -> is first looked
317 // up in the class of the object expression and the name, if found, is used.
318 // Otherwise, it is looked up in the context of the entire
319 // postfix-expression.
320 //
321 // This looks in the same scopes as for an unqualified destructor name:
322 //
323 // C++ [basic.lookup.classref]p3:
324 // If the unqualified-id is ~ type-name, the type-name is looked up
325 // in the context of the entire postfix-expression. If the type T
326 // of the object expression is of a class type C, the type-name is
327 // also looked up in the scope of class C. At least one of the
328 // lookups shall find a name that refers to cv T.
329 //
330 // FIXME: The intent is unclear here. Should type-name::~type-name look in
331 // the scope anyway if it finds a non-matching name declared in the class?
332 // If both lookups succeed and find a dependent result, which result should
333 // we retain? (Same question for p->~type-name().)
334
335 if (NestedNameSpecifier *Prefix =
336 SS.isSet() ? SS.getScopeRep()->getPrefix() : nullptr) {
337 // This is
338 //
339 // nested-name-specifier type-name :: ~ type-name
340 //
341 // Look for the second type-name in the nested-name-specifier.
342 CXXScopeSpec PrefixSS;
343 PrefixSS.Adopt(Other: NestedNameSpecifierLoc(Prefix, SS.location_data()));
344 if (ParsedType T = LookupInNestedNameSpec(PrefixSS))
345 return T;
346 } else {
347 // This is one of
348 //
349 // type-name :: ~ type-name
350 // ~ type-name
351 //
352 // Look in the scope and (if any) the object type.
353 if (ParsedType T = LookupInScope())
354 return T;
355 if (ParsedType T = LookupInObjectType())
356 return T;
357 }
358
359 if (Failed)
360 return nullptr;
361
362 if (IsDependent) {
363 // We didn't find our type, but that's OK: it's dependent anyway.
364
365 // FIXME: What if we have no nested-name-specifier?
366 QualType T =
367 CheckTypenameType(Keyword: ElaboratedTypeKeyword::None, KeywordLoc: SourceLocation(),
368 QualifierLoc: SS.getWithLocInContext(Context), II, IILoc: NameLoc);
369 return ParsedType::make(P: T);
370 }
371
372 // The remaining cases are all non-standard extensions imitating the behavior
373 // of various other compilers.
374 unsigned NumNonExtensionDecls = FoundDecls.size();
375
376 if (SS.isSet()) {
377 // For compatibility with older broken C++ rules and existing code,
378 //
379 // nested-name-specifier :: ~ type-name
380 //
381 // also looks for type-name within the nested-name-specifier.
382 if (ParsedType T = LookupInNestedNameSpec(SS)) {
383 Diag(Loc: SS.getEndLoc(), DiagID: diag::ext_dtor_named_in_wrong_scope)
384 << SS.getRange()
385 << FixItHint::CreateInsertion(InsertionLoc: SS.getEndLoc(),
386 Code: ("::" + II.getName()).str());
387 return T;
388 }
389
390 // For compatibility with other compilers and older versions of Clang,
391 //
392 // nested-name-specifier type-name :: ~ type-name
393 //
394 // also looks for type-name in the scope. Unfortunately, we can't
395 // reasonably apply this fallback for dependent nested-name-specifiers.
396 if (SS.isValid() && SS.getScopeRep()->getPrefix()) {
397 if (ParsedType T = LookupInScope()) {
398 Diag(Loc: SS.getEndLoc(), DiagID: diag::ext_qualified_dtor_named_in_lexical_scope)
399 << FixItHint::CreateRemoval(RemoveRange: SS.getRange());
400 Diag(Loc: FoundDecls.back()->getLocation(), DiagID: diag::note_destructor_type_here)
401 << GetTypeFromParser(Ty: T);
402 return T;
403 }
404 }
405 }
406
407 // We didn't find anything matching; tell the user what we did find (if
408 // anything).
409
410 // Don't tell the user about declarations we shouldn't have found.
411 FoundDecls.resize(N: NumNonExtensionDecls);
412
413 // List types before non-types.
414 std::stable_sort(first: FoundDecls.begin(), last: FoundDecls.end(),
415 comp: [](NamedDecl *A, NamedDecl *B) {
416 return isa<TypeDecl>(Val: A->getUnderlyingDecl()) >
417 isa<TypeDecl>(Val: B->getUnderlyingDecl());
418 });
419
420 // Suggest a fixit to properly name the destroyed type.
421 auto MakeFixItHint = [&]{
422 const CXXRecordDecl *Destroyed = nullptr;
423 // FIXME: If we have a scope specifier, suggest its last component?
424 if (!SearchType.isNull())
425 Destroyed = SearchType->getAsCXXRecordDecl();
426 else if (S)
427 Destroyed = dyn_cast_or_null<CXXRecordDecl>(Val: S->getEntity());
428 if (Destroyed)
429 return FixItHint::CreateReplacement(RemoveRange: SourceRange(NameLoc),
430 Code: Destroyed->getNameAsString());
431 return FixItHint();
432 };
433
434 if (FoundDecls.empty()) {
435 // FIXME: Attempt typo-correction?
436 Diag(Loc: NameLoc, DiagID: diag::err_undeclared_destructor_name)
437 << &II << MakeFixItHint();
438 } else if (!SearchType.isNull() && FoundDecls.size() == 1) {
439 if (auto *TD = dyn_cast<TypeDecl>(Val: FoundDecls[0]->getUnderlyingDecl())) {
440 assert(!SearchType.isNull() &&
441 "should only reject a type result if we have a search type");
442 QualType T = Context.getTypeDeclType(Decl: TD);
443 Diag(Loc: NameLoc, DiagID: diag::err_destructor_expr_type_mismatch)
444 << T << SearchType << MakeFixItHint();
445 } else {
446 Diag(Loc: NameLoc, DiagID: diag::err_destructor_expr_nontype)
447 << &II << MakeFixItHint();
448 }
449 } else {
450 Diag(Loc: NameLoc, DiagID: SearchType.isNull() ? diag::err_destructor_name_nontype
451 : diag::err_destructor_expr_mismatch)
452 << &II << SearchType << MakeFixItHint();
453 }
454
455 for (NamedDecl *FoundD : FoundDecls) {
456 if (auto *TD = dyn_cast<TypeDecl>(Val: FoundD->getUnderlyingDecl()))
457 Diag(Loc: FoundD->getLocation(), DiagID: diag::note_destructor_type_here)
458 << Context.getTypeDeclType(Decl: TD);
459 else
460 Diag(Loc: FoundD->getLocation(), DiagID: diag::note_destructor_nontype_here)
461 << FoundD;
462 }
463
464 return nullptr;
465}
466
467ParsedType Sema::getDestructorTypeForDecltype(const DeclSpec &DS,
468 ParsedType ObjectType) {
469 if (DS.getTypeSpecType() == DeclSpec::TST_error)
470 return nullptr;
471
472 if (DS.getTypeSpecType() == DeclSpec::TST_decltype_auto) {
473 Diag(Loc: DS.getTypeSpecTypeLoc(), DiagID: diag::err_decltype_auto_invalid);
474 return nullptr;
475 }
476
477 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&
478 "unexpected type in getDestructorType");
479 QualType T = BuildDecltypeType(E: DS.getRepAsExpr());
480
481 // If we know the type of the object, check that the correct destructor
482 // type was named now; we can give better diagnostics this way.
483 QualType SearchType = GetTypeFromParser(Ty: ObjectType);
484 if (!SearchType.isNull() && !SearchType->isDependentType() &&
485 !Context.hasSameUnqualifiedType(T1: T, T2: SearchType)) {
486 Diag(Loc: DS.getTypeSpecTypeLoc(), DiagID: diag::err_destructor_expr_type_mismatch)
487 << T << SearchType;
488 return nullptr;
489 }
490
491 return ParsedType::make(P: T);
492}
493
494bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
495 const UnqualifiedId &Name, bool IsUDSuffix) {
496 assert(Name.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId);
497 if (!IsUDSuffix) {
498 // [over.literal] p8
499 //
500 // double operator""_Bq(long double); // OK: not a reserved identifier
501 // double operator"" _Bq(long double); // ill-formed, no diagnostic required
502 const IdentifierInfo *II = Name.Identifier;
503 ReservedIdentifierStatus Status = II->isReserved(LangOpts: PP.getLangOpts());
504 SourceLocation Loc = Name.getEndLoc();
505 if (!PP.getSourceManager().isInSystemHeader(Loc)) {
506 if (auto Hint = FixItHint::CreateReplacement(
507 RemoveRange: Name.getSourceRange(),
508 Code: (StringRef("operator\"\"") + II->getName()).str());
509 isReservedInAllContexts(Status)) {
510 Diag(Loc, DiagID: diag::warn_reserved_extern_symbol)
511 << II << static_cast<int>(Status) << Hint;
512 } else {
513 Diag(Loc, DiagID: diag::warn_deprecated_literal_operator_id) << II << Hint;
514 }
515 }
516 }
517
518 if (!SS.isValid())
519 return false;
520
521 switch (SS.getScopeRep()->getKind()) {
522 case NestedNameSpecifier::Identifier:
523 case NestedNameSpecifier::TypeSpec:
524 case NestedNameSpecifier::TypeSpecWithTemplate:
525 // Per C++11 [over.literal]p2, literal operators can only be declared at
526 // namespace scope. Therefore, this unqualified-id cannot name anything.
527 // Reject it early, because we have no AST representation for this in the
528 // case where the scope is dependent.
529 Diag(Loc: Name.getBeginLoc(), DiagID: diag::err_literal_operator_id_outside_namespace)
530 << SS.getScopeRep();
531 return true;
532
533 case NestedNameSpecifier::Global:
534 case NestedNameSpecifier::Super:
535 case NestedNameSpecifier::Namespace:
536 case NestedNameSpecifier::NamespaceAlias:
537 return false;
538 }
539
540 llvm_unreachable("unknown nested name specifier kind");
541}
542
543ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
544 SourceLocation TypeidLoc,
545 TypeSourceInfo *Operand,
546 SourceLocation RParenLoc) {
547 // C++ [expr.typeid]p4:
548 // The top-level cv-qualifiers of the lvalue expression or the type-id
549 // that is the operand of typeid are always ignored.
550 // If the type of the type-id is a class type or a reference to a class
551 // type, the class shall be completely-defined.
552 Qualifiers Quals;
553 QualType T
554 = Context.getUnqualifiedArrayType(T: Operand->getType().getNonReferenceType(),
555 Quals);
556 if (T->getAs<RecordType>() &&
557 RequireCompleteType(Loc: TypeidLoc, T, DiagID: diag::err_incomplete_typeid))
558 return ExprError();
559
560 if (T->isVariablyModifiedType())
561 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_variably_modified_typeid) << T);
562
563 if (CheckQualifiedFunctionForTypeId(T, Loc: TypeidLoc))
564 return ExprError();
565
566 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
567 SourceRange(TypeidLoc, RParenLoc));
568}
569
570ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
571 SourceLocation TypeidLoc,
572 Expr *E,
573 SourceLocation RParenLoc) {
574 bool WasEvaluated = false;
575 if (E && !E->isTypeDependent()) {
576 if (E->hasPlaceholderType()) {
577 ExprResult result = CheckPlaceholderExpr(E);
578 if (result.isInvalid()) return ExprError();
579 E = result.get();
580 }
581
582 QualType T = E->getType();
583 if (const RecordType *RecordT = T->getAs<RecordType>()) {
584 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(Val: RecordT->getDecl());
585 // C++ [expr.typeid]p3:
586 // [...] If the type of the expression is a class type, the class
587 // shall be completely-defined.
588 if (RequireCompleteType(Loc: TypeidLoc, T, DiagID: diag::err_incomplete_typeid))
589 return ExprError();
590
591 // C++ [expr.typeid]p3:
592 // When typeid is applied to an expression other than an glvalue of a
593 // polymorphic class type [...] [the] expression is an unevaluated
594 // operand. [...]
595 if (RecordD->isPolymorphic() && E->isGLValue()) {
596 if (isUnevaluatedContext()) {
597 // The operand was processed in unevaluated context, switch the
598 // context and recheck the subexpression.
599 ExprResult Result = TransformToPotentiallyEvaluated(E);
600 if (Result.isInvalid())
601 return ExprError();
602 E = Result.get();
603 }
604
605 // We require a vtable to query the type at run time.
606 MarkVTableUsed(Loc: TypeidLoc, Class: RecordD);
607 WasEvaluated = true;
608 }
609 }
610
611 ExprResult Result = CheckUnevaluatedOperand(E);
612 if (Result.isInvalid())
613 return ExprError();
614 E = Result.get();
615
616 // C++ [expr.typeid]p4:
617 // [...] If the type of the type-id is a reference to a possibly
618 // cv-qualified type, the result of the typeid expression refers to a
619 // std::type_info object representing the cv-unqualified referenced
620 // type.
621 Qualifiers Quals;
622 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
623 if (!Context.hasSameType(T1: T, T2: UnqualT)) {
624 T = UnqualT;
625 E = ImpCastExprToType(E, Type: UnqualT, CK: CK_NoOp, VK: E->getValueKind()).get();
626 }
627 }
628
629 if (E->getType()->isVariablyModifiedType())
630 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_variably_modified_typeid)
631 << E->getType());
632 else if (!inTemplateInstantiation() &&
633 E->HasSideEffects(Ctx: Context, IncludePossibleEffects: WasEvaluated)) {
634 // The expression operand for typeid is in an unevaluated expression
635 // context, so side effects could result in unintended consequences.
636 Diag(Loc: E->getExprLoc(), DiagID: WasEvaluated
637 ? diag::warn_side_effects_typeid
638 : diag::warn_side_effects_unevaluated_context);
639 }
640
641 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
642 SourceRange(TypeidLoc, RParenLoc));
643}
644
645/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
646ExprResult
647Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
648 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
649 // typeid is not supported in OpenCL.
650 if (getLangOpts().OpenCLCPlusPlus) {
651 return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_openclcxx_not_supported)
652 << "typeid");
653 }
654
655 // Find the std::type_info type.
656 if (!getStdNamespace())
657 return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_need_header_before_typeid));
658
659 if (!CXXTypeInfoDecl) {
660 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get(Name: "type_info");
661 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
662 LookupQualifiedName(R, LookupCtx: getStdNamespace());
663 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
664 // Microsoft's typeinfo doesn't have type_info in std but in the global
665 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
666 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
667 LookupQualifiedName(R, LookupCtx: Context.getTranslationUnitDecl());
668 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
669 }
670 if (!CXXTypeInfoDecl)
671 return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_need_header_before_typeid));
672 }
673
674 if (!getLangOpts().RTTI) {
675 return ExprError(Diag(Loc: OpLoc, DiagID: diag::err_no_typeid_with_fno_rtti));
676 }
677
678 QualType TypeInfoType = Context.getTypeDeclType(Decl: CXXTypeInfoDecl);
679
680 if (isType) {
681 // The operand is a type; handle it as such.
682 TypeSourceInfo *TInfo = nullptr;
683 QualType T = GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: TyOrExpr),
684 TInfo: &TInfo);
685 if (T.isNull())
686 return ExprError();
687
688 if (!TInfo)
689 TInfo = Context.getTrivialTypeSourceInfo(T, Loc: OpLoc);
690
691 return BuildCXXTypeId(TypeInfoType, TypeidLoc: OpLoc, Operand: TInfo, RParenLoc);
692 }
693
694 // The operand is an expression.
695 ExprResult Result =
696 BuildCXXTypeId(TypeInfoType, TypeidLoc: OpLoc, E: (Expr *)TyOrExpr, RParenLoc);
697
698 if (!getLangOpts().RTTIData && !Result.isInvalid())
699 if (auto *CTE = dyn_cast<CXXTypeidExpr>(Val: Result.get()))
700 if (CTE->isPotentiallyEvaluated() && !CTE->isMostDerived(Context))
701 Diag(Loc: OpLoc, DiagID: diag::warn_no_typeid_with_rtti_disabled)
702 << (getDiagnostics().getDiagnosticOptions().getFormat() ==
703 DiagnosticOptions::MSVC);
704 return Result;
705}
706
707/// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
708/// a single GUID.
709static void
710getUuidAttrOfType(Sema &SemaRef, QualType QT,
711 llvm::SmallSetVector<const UuidAttr *, 1> &UuidAttrs) {
712 // Optionally remove one level of pointer, reference or array indirection.
713 const Type *Ty = QT.getTypePtr();
714 if (QT->isPointerType() || QT->isReferenceType())
715 Ty = QT->getPointeeType().getTypePtr();
716 else if (QT->isArrayType())
717 Ty = Ty->getBaseElementTypeUnsafe();
718
719 const auto *TD = Ty->getAsTagDecl();
720 if (!TD)
721 return;
722
723 if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
724 UuidAttrs.insert(X: Uuid);
725 return;
726 }
727
728 // __uuidof can grab UUIDs from template arguments.
729 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(Val: TD)) {
730 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
731 for (const TemplateArgument &TA : TAL.asArray()) {
732 const UuidAttr *UuidForTA = nullptr;
733 if (TA.getKind() == TemplateArgument::Type)
734 getUuidAttrOfType(SemaRef, QT: TA.getAsType(), UuidAttrs);
735 else if (TA.getKind() == TemplateArgument::Declaration)
736 getUuidAttrOfType(SemaRef, QT: TA.getAsDecl()->getType(), UuidAttrs);
737
738 if (UuidForTA)
739 UuidAttrs.insert(X: UuidForTA);
740 }
741 }
742}
743
744ExprResult Sema::BuildCXXUuidof(QualType Type,
745 SourceLocation TypeidLoc,
746 TypeSourceInfo *Operand,
747 SourceLocation RParenLoc) {
748 MSGuidDecl *Guid = nullptr;
749 if (!Operand->getType()->isDependentType()) {
750 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
751 getUuidAttrOfType(SemaRef&: *this, QT: Operand->getType(), UuidAttrs);
752 if (UuidAttrs.empty())
753 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_uuidof_without_guid));
754 if (UuidAttrs.size() > 1)
755 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_uuidof_with_multiple_guids));
756 Guid = UuidAttrs.back()->getGuidDecl();
757 }
758
759 return new (Context)
760 CXXUuidofExpr(Type, Operand, Guid, SourceRange(TypeidLoc, RParenLoc));
761}
762
763ExprResult Sema::BuildCXXUuidof(QualType Type, SourceLocation TypeidLoc,
764 Expr *E, SourceLocation RParenLoc) {
765 MSGuidDecl *Guid = nullptr;
766 if (!E->getType()->isDependentType()) {
767 if (E->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull)) {
768 // A null pointer results in {00000000-0000-0000-0000-000000000000}.
769 Guid = Context.getMSGuidDecl(Parts: MSGuidDecl::Parts{});
770 } else {
771 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
772 getUuidAttrOfType(SemaRef&: *this, QT: E->getType(), UuidAttrs);
773 if (UuidAttrs.empty())
774 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_uuidof_without_guid));
775 if (UuidAttrs.size() > 1)
776 return ExprError(Diag(Loc: TypeidLoc, DiagID: diag::err_uuidof_with_multiple_guids));
777 Guid = UuidAttrs.back()->getGuidDecl();
778 }
779 }
780
781 return new (Context)
782 CXXUuidofExpr(Type, E, Guid, SourceRange(TypeidLoc, RParenLoc));
783}
784
785/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
786ExprResult
787Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
788 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
789 QualType GuidType = Context.getMSGuidType();
790 GuidType.addConst();
791
792 if (isType) {
793 // The operand is a type; handle it as such.
794 TypeSourceInfo *TInfo = nullptr;
795 QualType T = GetTypeFromParser(Ty: ParsedType::getFromOpaquePtr(P: TyOrExpr),
796 TInfo: &TInfo);
797 if (T.isNull())
798 return ExprError();
799
800 if (!TInfo)
801 TInfo = Context.getTrivialTypeSourceInfo(T, Loc: OpLoc);
802
803 return BuildCXXUuidof(Type: GuidType, TypeidLoc: OpLoc, Operand: TInfo, RParenLoc);
804 }
805
806 // The operand is an expression.
807 return BuildCXXUuidof(Type: GuidType, TypeidLoc: OpLoc, E: (Expr*)TyOrExpr, RParenLoc);
808}
809
810ExprResult
811Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
812 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
813 "Unknown C++ Boolean value!");
814 return new (Context)
815 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
816}
817
818ExprResult
819Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
820 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
821}
822
823ExprResult
824Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
825 bool IsThrownVarInScope = false;
826 if (Ex) {
827 // C++0x [class.copymove]p31:
828 // When certain criteria are met, an implementation is allowed to omit the
829 // copy/move construction of a class object [...]
830 //
831 // - in a throw-expression, when the operand is the name of a
832 // non-volatile automatic object (other than a function or catch-
833 // clause parameter) whose scope does not extend beyond the end of the
834 // innermost enclosing try-block (if there is one), the copy/move
835 // operation from the operand to the exception object (15.1) can be
836 // omitted by constructing the automatic object directly into the
837 // exception object
838 if (const auto *DRE = dyn_cast<DeclRefExpr>(Val: Ex->IgnoreParens()))
839 if (const auto *Var = dyn_cast<VarDecl>(Val: DRE->getDecl());
840 Var && Var->hasLocalStorage() &&
841 !Var->getType().isVolatileQualified()) {
842 for (; S; S = S->getParent()) {
843 if (S->isDeclScope(D: Var)) {
844 IsThrownVarInScope = true;
845 break;
846 }
847
848 // FIXME: Many of the scope checks here seem incorrect.
849 if (S->getFlags() &
850 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
851 Scope::ObjCMethodScope | Scope::TryScope))
852 break;
853 }
854 }
855 }
856
857 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
858}
859
860ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
861 bool IsThrownVarInScope) {
862 const llvm::Triple &T = Context.getTargetInfo().getTriple();
863 const bool IsOpenMPGPUTarget =
864 getLangOpts().OpenMPIsTargetDevice && (T.isNVPTX() || T.isAMDGCN());
865 // Don't report an error if 'throw' is used in system headers or in an OpenMP
866 // target region compiled for a GPU architecture.
867 if (!IsOpenMPGPUTarget && !getLangOpts().CXXExceptions &&
868 !getSourceManager().isInSystemHeader(Loc: OpLoc) && !getLangOpts().CUDA) {
869 // Delay error emission for the OpenMP device code.
870 targetDiag(Loc: OpLoc, DiagID: diag::err_exceptions_disabled) << "throw";
871 }
872
873 // In OpenMP target regions, we replace 'throw' with a trap on GPU targets.
874 if (IsOpenMPGPUTarget)
875 targetDiag(Loc: OpLoc, DiagID: diag::warn_throw_not_valid_on_target) << T.str();
876
877 // Exceptions aren't allowed in CUDA device code.
878 if (getLangOpts().CUDA)
879 CUDA().DiagIfDeviceCode(Loc: OpLoc, DiagID: diag::err_cuda_device_exceptions)
880 << "throw" << llvm::to_underlying(E: CUDA().CurrentTarget());
881
882 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
883 Diag(Loc: OpLoc, DiagID: diag::err_omp_simd_region_cannot_use_stmt) << "throw";
884
885 // Exceptions that escape a compute construct are ill-formed.
886 if (getLangOpts().OpenACC && getCurScope() &&
887 getCurScope()->isInOpenACCComputeConstructScope(Flags: Scope::TryScope))
888 Diag(Loc: OpLoc, DiagID: diag::err_acc_branch_in_out_compute_construct)
889 << /*throw*/ 2 << /*out of*/ 0;
890
891 if (Ex && !Ex->isTypeDependent()) {
892 // Initialize the exception result. This implicitly weeds out
893 // abstract types or types with inaccessible copy constructors.
894
895 // C++0x [class.copymove]p31:
896 // When certain criteria are met, an implementation is allowed to omit the
897 // copy/move construction of a class object [...]
898 //
899 // - in a throw-expression, when the operand is the name of a
900 // non-volatile automatic object (other than a function or
901 // catch-clause
902 // parameter) whose scope does not extend beyond the end of the
903 // innermost enclosing try-block (if there is one), the copy/move
904 // operation from the operand to the exception object (15.1) can be
905 // omitted by constructing the automatic object directly into the
906 // exception object
907 NamedReturnInfo NRInfo =
908 IsThrownVarInScope ? getNamedReturnInfo(E&: Ex) : NamedReturnInfo();
909
910 QualType ExceptionObjectTy = Context.getExceptionObjectType(T: Ex->getType());
911 if (CheckCXXThrowOperand(ThrowLoc: OpLoc, ThrowTy: ExceptionObjectTy, E: Ex))
912 return ExprError();
913
914 InitializedEntity Entity =
915 InitializedEntity::InitializeException(ThrowLoc: OpLoc, Type: ExceptionObjectTy);
916 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRInfo, Value: Ex);
917 if (Res.isInvalid())
918 return ExprError();
919 Ex = Res.get();
920 }
921
922 // PPC MMA non-pointer types are not allowed as throw expr types.
923 if (Ex && Context.getTargetInfo().getTriple().isPPC64())
924 PPC().CheckPPCMMAType(Type: Ex->getType(), TypeLoc: Ex->getBeginLoc());
925
926 return new (Context)
927 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
928}
929
930static void
931collectPublicBases(CXXRecordDecl *RD,
932 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
933 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
934 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
935 bool ParentIsPublic) {
936 for (const CXXBaseSpecifier &BS : RD->bases()) {
937 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
938 bool NewSubobject;
939 // Virtual bases constitute the same subobject. Non-virtual bases are
940 // always distinct subobjects.
941 if (BS.isVirtual())
942 NewSubobject = VBases.insert(Ptr: BaseDecl).second;
943 else
944 NewSubobject = true;
945
946 if (NewSubobject)
947 ++SubobjectsSeen[BaseDecl];
948
949 // Only add subobjects which have public access throughout the entire chain.
950 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
951 if (PublicPath)
952 PublicSubobjectsSeen.insert(X: BaseDecl);
953
954 // Recurse on to each base subobject.
955 collectPublicBases(RD: BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
956 ParentIsPublic: PublicPath);
957 }
958}
959
960static void getUnambiguousPublicSubobjects(
961 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
962 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
963 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
964 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
965 SubobjectsSeen[RD] = 1;
966 PublicSubobjectsSeen.insert(X: RD);
967 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
968 /*ParentIsPublic=*/true);
969
970 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
971 // Skip ambiguous objects.
972 if (SubobjectsSeen[PublicSubobject] > 1)
973 continue;
974
975 Objects.push_back(Elt: PublicSubobject);
976 }
977}
978
979bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
980 QualType ExceptionObjectTy, Expr *E) {
981 // If the type of the exception would be an incomplete type or a pointer
982 // to an incomplete type other than (cv) void the program is ill-formed.
983 QualType Ty = ExceptionObjectTy;
984 bool isPointer = false;
985 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
986 Ty = Ptr->getPointeeType();
987 isPointer = true;
988 }
989
990 // Cannot throw WebAssembly reference type.
991 if (Ty.isWebAssemblyReferenceType()) {
992 Diag(Loc: ThrowLoc, DiagID: diag::err_wasm_reftype_tc) << 0 << E->getSourceRange();
993 return true;
994 }
995
996 // Cannot throw WebAssembly table.
997 if (isPointer && Ty.isWebAssemblyReferenceType()) {
998 Diag(Loc: ThrowLoc, DiagID: diag::err_wasm_table_art) << 2 << E->getSourceRange();
999 return true;
1000 }
1001
1002 if (!isPointer || !Ty->isVoidType()) {
1003 if (RequireCompleteType(Loc: ThrowLoc, T: Ty,
1004 DiagID: isPointer ? diag::err_throw_incomplete_ptr
1005 : diag::err_throw_incomplete,
1006 Args: E->getSourceRange()))
1007 return true;
1008
1009 if (!isPointer && Ty->isSizelessType()) {
1010 Diag(Loc: ThrowLoc, DiagID: diag::err_throw_sizeless) << Ty << E->getSourceRange();
1011 return true;
1012 }
1013
1014 if (RequireNonAbstractType(Loc: ThrowLoc, T: ExceptionObjectTy,
1015 DiagID: diag::err_throw_abstract_type, Args: E))
1016 return true;
1017 }
1018
1019 // If the exception has class type, we need additional handling.
1020 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
1021 if (!RD)
1022 return false;
1023
1024 // If we are throwing a polymorphic class type or pointer thereof,
1025 // exception handling will make use of the vtable.
1026 MarkVTableUsed(Loc: ThrowLoc, Class: RD);
1027
1028 // If a pointer is thrown, the referenced object will not be destroyed.
1029 if (isPointer)
1030 return false;
1031
1032 // If the class has a destructor, we must be able to call it.
1033 if (!RD->hasIrrelevantDestructor()) {
1034 if (CXXDestructorDecl *Destructor = LookupDestructor(Class: RD)) {
1035 MarkFunctionReferenced(Loc: E->getExprLoc(), Func: Destructor);
1036 CheckDestructorAccess(Loc: E->getExprLoc(), Dtor: Destructor,
1037 PDiag: PDiag(DiagID: diag::err_access_dtor_exception) << Ty);
1038 if (DiagnoseUseOfDecl(D: Destructor, Locs: E->getExprLoc()))
1039 return true;
1040 }
1041 }
1042
1043 // The MSVC ABI creates a list of all types which can catch the exception
1044 // object. This list also references the appropriate copy constructor to call
1045 // if the object is caught by value and has a non-trivial copy constructor.
1046 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1047 // We are only interested in the public, unambiguous bases contained within
1048 // the exception object. Bases which are ambiguous or otherwise
1049 // inaccessible are not catchable types.
1050 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
1051 getUnambiguousPublicSubobjects(RD, Objects&: UnambiguousPublicSubobjects);
1052
1053 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
1054 // Attempt to lookup the copy constructor. Various pieces of machinery
1055 // will spring into action, like template instantiation, which means this
1056 // cannot be a simple walk of the class's decls. Instead, we must perform
1057 // lookup and overload resolution.
1058 CXXConstructorDecl *CD = LookupCopyingConstructor(Class: Subobject, Quals: 0);
1059 if (!CD || CD->isDeleted())
1060 continue;
1061
1062 // Mark the constructor referenced as it is used by this throw expression.
1063 MarkFunctionReferenced(Loc: E->getExprLoc(), Func: CD);
1064
1065 // Skip this copy constructor if it is trivial, we don't need to record it
1066 // in the catchable type data.
1067 if (CD->isTrivial())
1068 continue;
1069
1070 // The copy constructor is non-trivial, create a mapping from this class
1071 // type to this constructor.
1072 // N.B. The selection of copy constructor is not sensitive to this
1073 // particular throw-site. Lookup will be performed at the catch-site to
1074 // ensure that the copy constructor is, in fact, accessible (via
1075 // friendship or any other means).
1076 Context.addCopyConstructorForExceptionObject(RD: Subobject, CD);
1077
1078 // We don't keep the instantiated default argument expressions around so
1079 // we must rebuild them here.
1080 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
1081 if (CheckCXXDefaultArgExpr(CallLoc: ThrowLoc, FD: CD, Param: CD->getParamDecl(i: I)))
1082 return true;
1083 }
1084 }
1085 }
1086
1087 // Under the Itanium C++ ABI, memory for the exception object is allocated by
1088 // the runtime with no ability for the compiler to request additional
1089 // alignment. Warn if the exception type requires alignment beyond the minimum
1090 // guaranteed by the target C++ runtime.
1091 if (Context.getTargetInfo().getCXXABI().isItaniumFamily()) {
1092 CharUnits TypeAlign = Context.getTypeAlignInChars(T: Ty);
1093 CharUnits ExnObjAlign = Context.getExnObjectAlignment();
1094 if (ExnObjAlign < TypeAlign) {
1095 Diag(Loc: ThrowLoc, DiagID: diag::warn_throw_underaligned_obj);
1096 Diag(Loc: ThrowLoc, DiagID: diag::note_throw_underaligned_obj)
1097 << Ty << (unsigned)TypeAlign.getQuantity()
1098 << (unsigned)ExnObjAlign.getQuantity();
1099 }
1100 }
1101 if (!isPointer && getLangOpts().AssumeNothrowExceptionDtor) {
1102 if (CXXDestructorDecl *Dtor = RD->getDestructor()) {
1103 auto Ty = Dtor->getType();
1104 if (auto *FT = Ty.getTypePtr()->getAs<FunctionProtoType>()) {
1105 if (!isUnresolvedExceptionSpec(ESpecType: FT->getExceptionSpecType()) &&
1106 !FT->isNothrow())
1107 Diag(Loc: ThrowLoc, DiagID: diag::err_throw_object_throwing_dtor) << RD;
1108 }
1109 }
1110 }
1111
1112 return false;
1113}
1114
1115static QualType adjustCVQualifiersForCXXThisWithinLambda(
1116 ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
1117 DeclContext *CurSemaContext, ASTContext &ASTCtx) {
1118
1119 QualType ClassType = ThisTy->getPointeeType();
1120 LambdaScopeInfo *CurLSI = nullptr;
1121 DeclContext *CurDC = CurSemaContext;
1122
1123 // Iterate through the stack of lambdas starting from the innermost lambda to
1124 // the outermost lambda, checking if '*this' is ever captured by copy - since
1125 // that could change the cv-qualifiers of the '*this' object.
1126 // The object referred to by '*this' starts out with the cv-qualifiers of its
1127 // member function. We then start with the innermost lambda and iterate
1128 // outward checking to see if any lambda performs a by-copy capture of '*this'
1129 // - and if so, any nested lambda must respect the 'constness' of that
1130 // capturing lamdbda's call operator.
1131 //
1132
1133 // Since the FunctionScopeInfo stack is representative of the lexical
1134 // nesting of the lambda expressions during initial parsing (and is the best
1135 // place for querying information about captures about lambdas that are
1136 // partially processed) and perhaps during instantiation of function templates
1137 // that contain lambda expressions that need to be transformed BUT not
1138 // necessarily during instantiation of a nested generic lambda's function call
1139 // operator (which might even be instantiated at the end of the TU) - at which
1140 // time the DeclContext tree is mature enough to query capture information
1141 // reliably - we use a two pronged approach to walk through all the lexically
1142 // enclosing lambda expressions:
1143 //
1144 // 1) Climb down the FunctionScopeInfo stack as long as each item represents
1145 // a Lambda (i.e. LambdaScopeInfo) AND each LSI's 'closure-type' is lexically
1146 // enclosed by the call-operator of the LSI below it on the stack (while
1147 // tracking the enclosing DC for step 2 if needed). Note the topmost LSI on
1148 // the stack represents the innermost lambda.
1149 //
1150 // 2) If we run out of enclosing LSI's, check if the enclosing DeclContext
1151 // represents a lambda's call operator. If it does, we must be instantiating
1152 // a generic lambda's call operator (represented by the Current LSI, and
1153 // should be the only scenario where an inconsistency between the LSI and the
1154 // DeclContext should occur), so climb out the DeclContexts if they
1155 // represent lambdas, while querying the corresponding closure types
1156 // regarding capture information.
1157
1158 // 1) Climb down the function scope info stack.
1159 for (int I = FunctionScopes.size();
1160 I-- && isa<LambdaScopeInfo>(Val: FunctionScopes[I]) &&
1161 (!CurLSI || !CurLSI->Lambda || CurLSI->Lambda->getDeclContext() ==
1162 cast<LambdaScopeInfo>(Val: FunctionScopes[I])->CallOperator);
1163 CurDC = getLambdaAwareParentOfDeclContext(DC: CurDC)) {
1164 CurLSI = cast<LambdaScopeInfo>(Val: FunctionScopes[I]);
1165
1166 if (!CurLSI->isCXXThisCaptured())
1167 continue;
1168
1169 auto C = CurLSI->getCXXThisCapture();
1170
1171 if (C.isCopyCapture()) {
1172 if (CurLSI->lambdaCaptureShouldBeConst())
1173 ClassType.addConst();
1174 return ASTCtx.getPointerType(T: ClassType);
1175 }
1176 }
1177
1178 // 2) We've run out of ScopeInfos but check 1. if CurDC is a lambda (which
1179 // can happen during instantiation of its nested generic lambda call
1180 // operator); 2. if we're in a lambda scope (lambda body).
1181 if (CurLSI && isLambdaCallOperator(DC: CurDC)) {
1182 assert(isGenericLambdaCallOperatorSpecialization(CurLSI->CallOperator) &&
1183 "While computing 'this' capture-type for a generic lambda, when we "
1184 "run out of enclosing LSI's, yet the enclosing DC is a "
1185 "lambda-call-operator we must be (i.e. Current LSI) in a generic "
1186 "lambda call oeprator");
1187 assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
1188
1189 auto IsThisCaptured =
1190 [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
1191 IsConst = false;
1192 IsByCopy = false;
1193 for (auto &&C : Closure->captures()) {
1194 if (C.capturesThis()) {
1195 if (C.getCaptureKind() == LCK_StarThis)
1196 IsByCopy = true;
1197 if (Closure->getLambdaCallOperator()->isConst())
1198 IsConst = true;
1199 return true;
1200 }
1201 }
1202 return false;
1203 };
1204
1205 bool IsByCopyCapture = false;
1206 bool IsConstCapture = false;
1207 CXXRecordDecl *Closure = cast<CXXRecordDecl>(Val: CurDC->getParent());
1208 while (Closure &&
1209 IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
1210 if (IsByCopyCapture) {
1211 if (IsConstCapture)
1212 ClassType.addConst();
1213 return ASTCtx.getPointerType(T: ClassType);
1214 }
1215 Closure = isLambdaCallOperator(DC: Closure->getParent())
1216 ? cast<CXXRecordDecl>(Val: Closure->getParent()->getParent())
1217 : nullptr;
1218 }
1219 }
1220 return ThisTy;
1221}
1222
1223QualType Sema::getCurrentThisType() {
1224 DeclContext *DC = getFunctionLevelDeclContext();
1225 QualType ThisTy = CXXThisTypeOverride;
1226
1227 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(Val: DC)) {
1228 if (method && method->isImplicitObjectMemberFunction())
1229 ThisTy = method->getThisType().getNonReferenceType();
1230 }
1231
1232 if (ThisTy.isNull() && isLambdaCallWithImplicitObjectParameter(DC: CurContext) &&
1233 inTemplateInstantiation() && isa<CXXRecordDecl>(Val: DC)) {
1234
1235 // This is a lambda call operator that is being instantiated as a default
1236 // initializer. DC must point to the enclosing class type, so we can recover
1237 // the 'this' type from it.
1238 QualType ClassTy = Context.getTypeDeclType(Decl: cast<CXXRecordDecl>(Val: DC));
1239 // There are no cv-qualifiers for 'this' within default initializers,
1240 // per [expr.prim.general]p4.
1241 ThisTy = Context.getPointerType(T: ClassTy);
1242 }
1243
1244 // If we are within a lambda's call operator, the cv-qualifiers of 'this'
1245 // might need to be adjusted if the lambda or any of its enclosing lambda's
1246 // captures '*this' by copy.
1247 if (!ThisTy.isNull() && isLambdaCallOperator(DC: CurContext))
1248 return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1249 CurSemaContext: CurContext, ASTCtx&: Context);
1250 return ThisTy;
1251}
1252
1253Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
1254 Decl *ContextDecl,
1255 Qualifiers CXXThisTypeQuals,
1256 bool Enabled)
1257 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1258{
1259 if (!Enabled || !ContextDecl)
1260 return;
1261
1262 CXXRecordDecl *Record = nullptr;
1263 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(Val: ContextDecl))
1264 Record = Template->getTemplatedDecl();
1265 else
1266 Record = cast<CXXRecordDecl>(Val: ContextDecl);
1267
1268 QualType T = S.Context.getRecordType(Decl: Record);
1269 T = S.getASTContext().getQualifiedType(T, Qs: CXXThisTypeQuals);
1270
1271 S.CXXThisTypeOverride =
1272 S.Context.getLangOpts().HLSL ? T : S.Context.getPointerType(T);
1273
1274 this->Enabled = true;
1275}
1276
1277
1278Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
1279 if (Enabled) {
1280 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1281 }
1282}
1283
1284static void buildLambdaThisCaptureFixit(Sema &Sema, LambdaScopeInfo *LSI) {
1285 SourceLocation DiagLoc = LSI->IntroducerRange.getEnd();
1286 assert(!LSI->isCXXThisCaptured());
1287 // [=, this] {}; // until C++20: Error: this when = is the default
1288 if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval &&
1289 !Sema.getLangOpts().CPlusPlus20)
1290 return;
1291 Sema.Diag(Loc: DiagLoc, DiagID: diag::note_lambda_this_capture_fixit)
1292 << FixItHint::CreateInsertion(
1293 InsertionLoc: DiagLoc, Code: LSI->NumExplicitCaptures > 0 ? ", this" : "this");
1294}
1295
1296bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1297 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1298 const bool ByCopy) {
1299 // We don't need to capture this in an unevaluated context.
1300 if (isUnevaluatedContext() && !Explicit)
1301 return true;
1302
1303 assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1304
1305 const int MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
1306 ? *FunctionScopeIndexToStopAt
1307 : FunctionScopes.size() - 1;
1308
1309 // Check that we can capture the *enclosing object* (referred to by '*this')
1310 // by the capturing-entity/closure (lambda/block/etc) at
1311 // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1312
1313 // Note: The *enclosing object* can only be captured by-value by a
1314 // closure that is a lambda, using the explicit notation:
1315 // [*this] { ... }.
1316 // Every other capture of the *enclosing object* results in its by-reference
1317 // capture.
1318
1319 // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1320 // stack), we can capture the *enclosing object* only if:
1321 // - 'L' has an explicit byref or byval capture of the *enclosing object*
1322 // - or, 'L' has an implicit capture.
1323 // AND
1324 // -- there is no enclosing closure
1325 // -- or, there is some enclosing closure 'E' that has already captured the
1326 // *enclosing object*, and every intervening closure (if any) between 'E'
1327 // and 'L' can implicitly capture the *enclosing object*.
1328 // -- or, every enclosing closure can implicitly capture the
1329 // *enclosing object*
1330
1331
1332 unsigned NumCapturingClosures = 0;
1333 for (int idx = MaxFunctionScopesIndex; idx >= 0; idx--) {
1334 if (CapturingScopeInfo *CSI =
1335 dyn_cast<CapturingScopeInfo>(Val: FunctionScopes[idx])) {
1336 if (CSI->CXXThisCaptureIndex != 0) {
1337 // 'this' is already being captured; there isn't anything more to do.
1338 CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(IsODRUse: BuildAndDiagnose);
1339 break;
1340 }
1341 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(Val: CSI);
1342 if (LSI && isGenericLambdaCallOperatorSpecialization(MD: LSI->CallOperator)) {
1343 // This context can't implicitly capture 'this'; fail out.
1344 if (BuildAndDiagnose) {
1345 LSI->CallOperator->setInvalidDecl();
1346 Diag(Loc, DiagID: diag::err_this_capture)
1347 << (Explicit && idx == MaxFunctionScopesIndex);
1348 if (!Explicit)
1349 buildLambdaThisCaptureFixit(Sema&: *this, LSI);
1350 }
1351 return true;
1352 }
1353 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1354 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1355 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1356 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1357 (Explicit && idx == MaxFunctionScopesIndex)) {
1358 // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1359 // iteration through can be an explicit capture, all enclosing closures,
1360 // if any, must perform implicit captures.
1361
1362 // This closure can capture 'this'; continue looking upwards.
1363 NumCapturingClosures++;
1364 continue;
1365 }
1366 // This context can't implicitly capture 'this'; fail out.
1367 if (BuildAndDiagnose) {
1368 LSI->CallOperator->setInvalidDecl();
1369 Diag(Loc, DiagID: diag::err_this_capture)
1370 << (Explicit && idx == MaxFunctionScopesIndex);
1371 }
1372 if (!Explicit)
1373 buildLambdaThisCaptureFixit(Sema&: *this, LSI);
1374 return true;
1375 }
1376 break;
1377 }
1378 if (!BuildAndDiagnose) return false;
1379
1380 // If we got here, then the closure at MaxFunctionScopesIndex on the
1381 // FunctionScopes stack, can capture the *enclosing object*, so capture it
1382 // (including implicit by-reference captures in any enclosing closures).
1383
1384 // In the loop below, respect the ByCopy flag only for the closure requesting
1385 // the capture (i.e. first iteration through the loop below). Ignore it for
1386 // all enclosing closure's up to NumCapturingClosures (since they must be
1387 // implicitly capturing the *enclosing object* by reference (see loop
1388 // above)).
1389 assert((!ByCopy ||
1390 isa<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1391 "Only a lambda can capture the enclosing object (referred to by "
1392 "*this) by copy");
1393 QualType ThisTy = getCurrentThisType();
1394 for (int idx = MaxFunctionScopesIndex; NumCapturingClosures;
1395 --idx, --NumCapturingClosures) {
1396 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(Val: FunctionScopes[idx]);
1397
1398 // The type of the corresponding data member (not a 'this' pointer if 'by
1399 // copy').
1400 QualType CaptureType = ByCopy ? ThisTy->getPointeeType() : ThisTy;
1401
1402 bool isNested = NumCapturingClosures > 1;
1403 CSI->addThisCapture(isNested, Loc, CaptureType, ByCopy);
1404 }
1405 return false;
1406}
1407
1408ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
1409 // C++20 [expr.prim.this]p1:
1410 // The keyword this names a pointer to the object for which an
1411 // implicit object member function is invoked or a non-static
1412 // data member's initializer is evaluated.
1413 QualType ThisTy = getCurrentThisType();
1414
1415 if (CheckCXXThisType(Loc, Type: ThisTy))
1416 return ExprError();
1417
1418 return BuildCXXThisExpr(Loc, Type: ThisTy, /*IsImplicit=*/false);
1419}
1420
1421bool Sema::CheckCXXThisType(SourceLocation Loc, QualType Type) {
1422 if (!Type.isNull())
1423 return false;
1424
1425 // C++20 [expr.prim.this]p3:
1426 // If a declaration declares a member function or member function template
1427 // of a class X, the expression this is a prvalue of type
1428 // "pointer to cv-qualifier-seq X" wherever X is the current class between
1429 // the optional cv-qualifier-seq and the end of the function-definition,
1430 // member-declarator, or declarator. It shall not appear within the
1431 // declaration of either a static member function or an explicit object
1432 // member function of the current class (although its type and value
1433 // category are defined within such member functions as they are within
1434 // an implicit object member function).
1435 DeclContext *DC = getFunctionLevelDeclContext();
1436 const auto *Method = dyn_cast<CXXMethodDecl>(Val: DC);
1437 if (Method && Method->isExplicitObjectMemberFunction()) {
1438 Diag(Loc, DiagID: diag::err_invalid_this_use) << 1;
1439 } else if (Method && isLambdaCallWithExplicitObjectParameter(DC: CurContext)) {
1440 Diag(Loc, DiagID: diag::err_invalid_this_use) << 1;
1441 } else {
1442 Diag(Loc, DiagID: diag::err_invalid_this_use) << 0;
1443 }
1444 return true;
1445}
1446
1447Expr *Sema::BuildCXXThisExpr(SourceLocation Loc, QualType Type,
1448 bool IsImplicit) {
1449 auto *This = CXXThisExpr::Create(Ctx: Context, L: Loc, Ty: Type, IsImplicit);
1450 MarkThisReferenced(This);
1451 return This;
1452}
1453
1454void Sema::MarkThisReferenced(CXXThisExpr *This) {
1455 CheckCXXThisCapture(Loc: This->getExprLoc());
1456 if (This->isTypeDependent())
1457 return;
1458
1459 // Check if 'this' is captured by value in a lambda with a dependent explicit
1460 // object parameter, and mark it as type-dependent as well if so.
1461 auto IsDependent = [&]() {
1462 for (auto *Scope : llvm::reverse(C&: FunctionScopes)) {
1463 auto *LSI = dyn_cast<sema::LambdaScopeInfo>(Val: Scope);
1464 if (!LSI)
1465 continue;
1466
1467 if (LSI->Lambda && !LSI->Lambda->Encloses(DC: CurContext) &&
1468 LSI->AfterParameterList)
1469 return false;
1470
1471 // If this lambda captures 'this' by value, then 'this' is dependent iff
1472 // this lambda has a dependent explicit object parameter. If we can't
1473 // determine whether it does (e.g. because the CXXMethodDecl's type is
1474 // null), assume it doesn't.
1475 if (LSI->isCXXThisCaptured()) {
1476 if (!LSI->getCXXThisCapture().isCopyCapture())
1477 continue;
1478
1479 const auto *MD = LSI->CallOperator;
1480 if (MD->getType().isNull())
1481 return false;
1482
1483 const auto *Ty = MD->getType()->getAs<FunctionProtoType>();
1484 return Ty && MD->isExplicitObjectMemberFunction() &&
1485 Ty->getParamType(i: 0)->isDependentType();
1486 }
1487 }
1488 return false;
1489 }();
1490
1491 This->setCapturedByCopyInLambdaWithExplicitObjectParameter(IsDependent);
1492}
1493
1494bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
1495 // If we're outside the body of a member function, then we'll have a specified
1496 // type for 'this'.
1497 if (CXXThisTypeOverride.isNull())
1498 return false;
1499
1500 // Determine whether we're looking into a class that's currently being
1501 // defined.
1502 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1503 return Class && Class->isBeingDefined();
1504}
1505
1506ExprResult
1507Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
1508 SourceLocation LParenOrBraceLoc,
1509 MultiExprArg exprs,
1510 SourceLocation RParenOrBraceLoc,
1511 bool ListInitialization) {
1512 if (!TypeRep)
1513 return ExprError();
1514
1515 TypeSourceInfo *TInfo;
1516 QualType Ty = GetTypeFromParser(Ty: TypeRep, TInfo: &TInfo);
1517 if (!TInfo)
1518 TInfo = Context.getTrivialTypeSourceInfo(T: Ty, Loc: SourceLocation());
1519
1520 auto Result = BuildCXXTypeConstructExpr(Type: TInfo, LParenLoc: LParenOrBraceLoc, Exprs: exprs,
1521 RParenLoc: RParenOrBraceLoc, ListInitialization);
1522 // Avoid creating a non-type-dependent expression that contains typos.
1523 // Non-type-dependent expressions are liable to be discarded without
1524 // checking for embedded typos.
1525 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1526 !Result.get()->isTypeDependent())
1527 Result = CorrectDelayedTyposInExpr(E: Result.get());
1528 else if (Result.isInvalid())
1529 Result = CreateRecoveryExpr(Begin: TInfo->getTypeLoc().getBeginLoc(),
1530 End: RParenOrBraceLoc, SubExprs: exprs, T: Ty);
1531 return Result;
1532}
1533
1534ExprResult
1535Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1536 SourceLocation LParenOrBraceLoc,
1537 MultiExprArg Exprs,
1538 SourceLocation RParenOrBraceLoc,
1539 bool ListInitialization) {
1540 QualType Ty = TInfo->getType();
1541 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1542
1543 assert((!ListInitialization || Exprs.size() == 1) &&
1544 "List initialization must have exactly one expression.");
1545 SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc);
1546
1547 InitializedEntity Entity =
1548 InitializedEntity::InitializeTemporary(Context, TypeInfo: TInfo);
1549 InitializationKind Kind =
1550 Exprs.size()
1551 ? ListInitialization
1552 ? InitializationKind::CreateDirectList(
1553 InitLoc: TyBeginLoc, LBraceLoc: LParenOrBraceLoc, RBraceLoc: RParenOrBraceLoc)
1554 : InitializationKind::CreateDirect(InitLoc: TyBeginLoc, LParenLoc: LParenOrBraceLoc,
1555 RParenLoc: RParenOrBraceLoc)
1556 : InitializationKind::CreateValue(InitLoc: TyBeginLoc, LParenLoc: LParenOrBraceLoc,
1557 RParenLoc: RParenOrBraceLoc);
1558
1559 // C++17 [expr.type.conv]p1:
1560 // If the type is a placeholder for a deduced class type, [...perform class
1561 // template argument deduction...]
1562 // C++23:
1563 // Otherwise, if the type contains a placeholder type, it is replaced by the
1564 // type determined by placeholder type deduction.
1565 DeducedType *Deduced = Ty->getContainedDeducedType();
1566 if (Deduced && !Deduced->isDeduced() &&
1567 isa<DeducedTemplateSpecializationType>(Val: Deduced)) {
1568 Ty = DeduceTemplateSpecializationFromInitializer(TInfo, Entity,
1569 Kind, Init: Exprs);
1570 if (Ty.isNull())
1571 return ExprError();
1572 Entity = InitializedEntity::InitializeTemporary(TypeInfo: TInfo, Type: Ty);
1573 } else if (Deduced && !Deduced->isDeduced()) {
1574 MultiExprArg Inits = Exprs;
1575 if (ListInitialization) {
1576 auto *ILE = cast<InitListExpr>(Val: Exprs[0]);
1577 Inits = MultiExprArg(ILE->getInits(), ILE->getNumInits());
1578 }
1579
1580 if (Inits.empty())
1581 return ExprError(Diag(Loc: TyBeginLoc, DiagID: diag::err_auto_expr_init_no_expression)
1582 << Ty << FullRange);
1583 if (Inits.size() > 1) {
1584 Expr *FirstBad = Inits[1];
1585 return ExprError(Diag(Loc: FirstBad->getBeginLoc(),
1586 DiagID: diag::err_auto_expr_init_multiple_expressions)
1587 << Ty << FullRange);
1588 }
1589 if (getLangOpts().CPlusPlus23) {
1590 if (Ty->getAs<AutoType>())
1591 Diag(Loc: TyBeginLoc, DiagID: diag::warn_cxx20_compat_auto_expr) << FullRange;
1592 }
1593 Expr *Deduce = Inits[0];
1594 if (isa<InitListExpr>(Val: Deduce))
1595 return ExprError(
1596 Diag(Loc: Deduce->getBeginLoc(), DiagID: diag::err_auto_expr_init_paren_braces)
1597 << ListInitialization << Ty << FullRange);
1598 QualType DeducedType;
1599 TemplateDeductionInfo Info(Deduce->getExprLoc());
1600 TemplateDeductionResult Result =
1601 DeduceAutoType(AutoTypeLoc: TInfo->getTypeLoc(), Initializer: Deduce, Result&: DeducedType, Info);
1602 if (Result != TemplateDeductionResult::Success &&
1603 Result != TemplateDeductionResult::AlreadyDiagnosed)
1604 return ExprError(Diag(Loc: TyBeginLoc, DiagID: diag::err_auto_expr_deduction_failure)
1605 << Ty << Deduce->getType() << FullRange
1606 << Deduce->getSourceRange());
1607 if (DeducedType.isNull()) {
1608 assert(Result == TemplateDeductionResult::AlreadyDiagnosed);
1609 return ExprError();
1610 }
1611
1612 Ty = DeducedType;
1613 Entity = InitializedEntity::InitializeTemporary(TypeInfo: TInfo, Type: Ty);
1614 }
1615
1616 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs))
1617 return CXXUnresolvedConstructExpr::Create(
1618 Context, T: Ty.getNonReferenceType(), TSI: TInfo, LParenLoc: LParenOrBraceLoc, Args: Exprs,
1619 RParenLoc: RParenOrBraceLoc, IsListInit: ListInitialization);
1620
1621 // C++ [expr.type.conv]p1:
1622 // If the expression list is a parenthesized single expression, the type
1623 // conversion expression is equivalent (in definedness, and if defined in
1624 // meaning) to the corresponding cast expression.
1625 if (Exprs.size() == 1 && !ListInitialization &&
1626 !isa<InitListExpr>(Val: Exprs[0])) {
1627 Expr *Arg = Exprs[0];
1628 return BuildCXXFunctionalCastExpr(TInfo, Type: Ty, LParenLoc: LParenOrBraceLoc, CastExpr: Arg,
1629 RParenLoc: RParenOrBraceLoc);
1630 }
1631
1632 // For an expression of the form T(), T shall not be an array type.
1633 QualType ElemTy = Ty;
1634 if (Ty->isArrayType()) {
1635 if (!ListInitialization)
1636 return ExprError(Diag(Loc: TyBeginLoc, DiagID: diag::err_value_init_for_array_type)
1637 << FullRange);
1638 ElemTy = Context.getBaseElementType(QT: Ty);
1639 }
1640
1641 // Only construct objects with object types.
1642 // The standard doesn't explicitly forbid function types here, but that's an
1643 // obvious oversight, as there's no way to dynamically construct a function
1644 // in general.
1645 if (Ty->isFunctionType())
1646 return ExprError(Diag(Loc: TyBeginLoc, DiagID: diag::err_init_for_function_type)
1647 << Ty << FullRange);
1648
1649 // C++17 [expr.type.conv]p2:
1650 // If the type is cv void and the initializer is (), the expression is a
1651 // prvalue of the specified type that performs no initialization.
1652 if (!Ty->isVoidType() &&
1653 RequireCompleteType(Loc: TyBeginLoc, T: ElemTy,
1654 DiagID: diag::err_invalid_incomplete_type_use, Args: FullRange))
1655 return ExprError();
1656
1657 // Otherwise, the expression is a prvalue of the specified type whose
1658 // result object is direct-initialized (11.6) with the initializer.
1659 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1660 ExprResult Result = InitSeq.Perform(S&: *this, Entity, Kind, Args: Exprs);
1661
1662 if (Result.isInvalid())
1663 return Result;
1664
1665 Expr *Inner = Result.get();
1666 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Val: Inner))
1667 Inner = BTE->getSubExpr();
1668 if (auto *CE = dyn_cast<ConstantExpr>(Val: Inner);
1669 CE && CE->isImmediateInvocation())
1670 Inner = CE->getSubExpr();
1671 if (!isa<CXXTemporaryObjectExpr>(Val: Inner) &&
1672 !isa<CXXScalarValueInitExpr>(Val: Inner)) {
1673 // If we created a CXXTemporaryObjectExpr, that node also represents the
1674 // functional cast. Otherwise, create an explicit cast to represent
1675 // the syntactic form of a functional-style cast that was used here.
1676 //
1677 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1678 // would give a more consistent AST representation than using a
1679 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1680 // is sometimes handled by initialization and sometimes not.
1681 QualType ResultType = Result.get()->getType();
1682 SourceRange Locs = ListInitialization
1683 ? SourceRange()
1684 : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1685 Result = CXXFunctionalCastExpr::Create(
1686 Context, T: ResultType, VK: Expr::getValueKindForType(T: Ty), Written: TInfo, Kind: CK_NoOp,
1687 Op: Result.get(), /*Path=*/nullptr, FPO: CurFPFeatureOverrides(),
1688 LPLoc: Locs.getBegin(), RPLoc: Locs.getEnd());
1689 }
1690
1691 return Result;
1692}
1693
1694bool Sema::isUsualDeallocationFunction(const CXXMethodDecl *Method) {
1695 // [CUDA] Ignore this function, if we can't call it.
1696 const FunctionDecl *Caller = getCurFunctionDecl(/*AllowLambda=*/true);
1697 if (getLangOpts().CUDA) {
1698 auto CallPreference = CUDA().IdentifyPreference(Caller, Callee: Method);
1699 // If it's not callable at all, it's not the right function.
1700 if (CallPreference < SemaCUDA::CFP_WrongSide)
1701 return false;
1702 if (CallPreference == SemaCUDA::CFP_WrongSide) {
1703 // Maybe. We have to check if there are better alternatives.
1704 DeclContext::lookup_result R =
1705 Method->getDeclContext()->lookup(Name: Method->getDeclName());
1706 for (const auto *D : R) {
1707 if (const auto *FD = dyn_cast<FunctionDecl>(Val: D)) {
1708 if (CUDA().IdentifyPreference(Caller, Callee: FD) > SemaCUDA::CFP_WrongSide)
1709 return false;
1710 }
1711 }
1712 // We've found no better variants.
1713 }
1714 }
1715
1716 SmallVector<const FunctionDecl*, 4> PreventedBy;
1717 bool Result = Method->isUsualDeallocationFunction(PreventedBy);
1718
1719 if (Result || !getLangOpts().CUDA || PreventedBy.empty())
1720 return Result;
1721
1722 // In case of CUDA, return true if none of the 1-argument deallocator
1723 // functions are actually callable.
1724 return llvm::none_of(Range&: PreventedBy, P: [&](const FunctionDecl *FD) {
1725 assert(FD->getNumParams() == 1 &&
1726 "Only single-operand functions should be in PreventedBy");
1727 return CUDA().IdentifyPreference(Caller, Callee: FD) >= SemaCUDA::CFP_HostDevice;
1728 });
1729}
1730
1731/// Determine whether the given function is a non-placement
1732/// deallocation function.
1733static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1734 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Val: FD))
1735 return S.isUsualDeallocationFunction(Method);
1736
1737 if (FD->getOverloadedOperator() != OO_Delete &&
1738 FD->getOverloadedOperator() != OO_Array_Delete)
1739 return false;
1740
1741 unsigned UsualParams = 1;
1742
1743 if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1744 S.Context.hasSameUnqualifiedType(
1745 T1: FD->getParamDecl(i: UsualParams)->getType(),
1746 T2: S.Context.getSizeType()))
1747 ++UsualParams;
1748
1749 if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1750 S.Context.hasSameUnqualifiedType(
1751 T1: FD->getParamDecl(i: UsualParams)->getType(),
1752 T2: S.Context.getTypeDeclType(Decl: S.getStdAlignValT())))
1753 ++UsualParams;
1754
1755 return UsualParams == FD->getNumParams();
1756}
1757
1758namespace {
1759 struct UsualDeallocFnInfo {
1760 UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1761 UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1762 : Found(Found), FD(dyn_cast<FunctionDecl>(Val: Found->getUnderlyingDecl())),
1763 Destroying(false), HasSizeT(false), HasAlignValT(false),
1764 CUDAPref(SemaCUDA::CFP_Native) {
1765 // A function template declaration is never a usual deallocation function.
1766 if (!FD)
1767 return;
1768 unsigned NumBaseParams = 1;
1769 if (FD->isDestroyingOperatorDelete()) {
1770 Destroying = true;
1771 ++NumBaseParams;
1772 }
1773
1774 if (NumBaseParams < FD->getNumParams() &&
1775 S.Context.hasSameUnqualifiedType(
1776 T1: FD->getParamDecl(i: NumBaseParams)->getType(),
1777 T2: S.Context.getSizeType())) {
1778 ++NumBaseParams;
1779 HasSizeT = true;
1780 }
1781
1782 if (NumBaseParams < FD->getNumParams() &&
1783 FD->getParamDecl(i: NumBaseParams)->getType()->isAlignValT()) {
1784 ++NumBaseParams;
1785 HasAlignValT = true;
1786 }
1787
1788 // In CUDA, determine how much we'd like / dislike to call this.
1789 if (S.getLangOpts().CUDA)
1790 CUDAPref = S.CUDA().IdentifyPreference(
1791 Caller: S.getCurFunctionDecl(/*AllowLambda=*/true), Callee: FD);
1792 }
1793
1794 explicit operator bool() const { return FD; }
1795
1796 bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1797 bool WantAlign) const {
1798 // C++ P0722:
1799 // A destroying operator delete is preferred over a non-destroying
1800 // operator delete.
1801 if (Destroying != Other.Destroying)
1802 return Destroying;
1803
1804 // C++17 [expr.delete]p10:
1805 // If the type has new-extended alignment, a function with a parameter
1806 // of type std::align_val_t is preferred; otherwise a function without
1807 // such a parameter is preferred
1808 if (HasAlignValT != Other.HasAlignValT)
1809 return HasAlignValT == WantAlign;
1810
1811 if (HasSizeT != Other.HasSizeT)
1812 return HasSizeT == WantSize;
1813
1814 // Use CUDA call preference as a tiebreaker.
1815 return CUDAPref > Other.CUDAPref;
1816 }
1817
1818 DeclAccessPair Found;
1819 FunctionDecl *FD;
1820 bool Destroying, HasSizeT, HasAlignValT;
1821 SemaCUDA::CUDAFunctionPreference CUDAPref;
1822 };
1823}
1824
1825/// Determine whether a type has new-extended alignment. This may be called when
1826/// the type is incomplete (for a delete-expression with an incomplete pointee
1827/// type), in which case it will conservatively return false if the alignment is
1828/// not known.
1829static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1830 return S.getLangOpts().AlignedAllocation &&
1831 S.getASTContext().getTypeAlignIfKnown(T: AllocType) >
1832 S.getASTContext().getTargetInfo().getNewAlign();
1833}
1834
1835/// Select the correct "usual" deallocation function to use from a selection of
1836/// deallocation functions (either global or class-scope).
1837static UsualDeallocFnInfo resolveDeallocationOverload(
1838 Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1839 llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1840 UsualDeallocFnInfo Best;
1841
1842 for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1843 UsualDeallocFnInfo Info(S, I.getPair());
1844 if (!Info || !isNonPlacementDeallocationFunction(S, FD: Info.FD) ||
1845 Info.CUDAPref == SemaCUDA::CFP_Never)
1846 continue;
1847
1848 if (!Best) {
1849 Best = Info;
1850 if (BestFns)
1851 BestFns->push_back(Elt: Info);
1852 continue;
1853 }
1854
1855 if (Best.isBetterThan(Other: Info, WantSize, WantAlign))
1856 continue;
1857
1858 // If more than one preferred function is found, all non-preferred
1859 // functions are eliminated from further consideration.
1860 if (BestFns && Info.isBetterThan(Other: Best, WantSize, WantAlign))
1861 BestFns->clear();
1862
1863 Best = Info;
1864 if (BestFns)
1865 BestFns->push_back(Elt: Info);
1866 }
1867
1868 return Best;
1869}
1870
1871/// Determine whether a given type is a class for which 'delete[]' would call
1872/// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1873/// we need to store the array size (even if the type is
1874/// trivially-destructible).
1875static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1876 QualType allocType) {
1877 const RecordType *record =
1878 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1879 if (!record) return false;
1880
1881 // Try to find an operator delete[] in class scope.
1882
1883 DeclarationName deleteName =
1884 S.Context.DeclarationNames.getCXXOperatorName(Op: OO_Array_Delete);
1885 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1886 S.LookupQualifiedName(R&: ops, LookupCtx: record->getDecl());
1887
1888 // We're just doing this for information.
1889 ops.suppressDiagnostics();
1890
1891 // Very likely: there's no operator delete[].
1892 if (ops.empty()) return false;
1893
1894 // If it's ambiguous, it should be illegal to call operator delete[]
1895 // on this thing, so it doesn't matter if we allocate extra space or not.
1896 if (ops.isAmbiguous()) return false;
1897
1898 // C++17 [expr.delete]p10:
1899 // If the deallocation functions have class scope, the one without a
1900 // parameter of type std::size_t is selected.
1901 auto Best = resolveDeallocationOverload(
1902 S, R&: ops, /*WantSize*/false,
1903 /*WantAlign*/hasNewExtendedAlignment(S, AllocType: allocType));
1904 return Best && Best.HasSizeT;
1905}
1906
1907ExprResult
1908Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1909 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1910 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1911 Declarator &D, Expr *Initializer) {
1912 std::optional<Expr *> ArraySize;
1913 // If the specified type is an array, unwrap it and save the expression.
1914 if (D.getNumTypeObjects() > 0 &&
1915 D.getTypeObject(i: 0).Kind == DeclaratorChunk::Array) {
1916 DeclaratorChunk &Chunk = D.getTypeObject(i: 0);
1917 if (D.getDeclSpec().hasAutoTypeSpec())
1918 return ExprError(Diag(Loc: Chunk.Loc, DiagID: diag::err_new_array_of_auto)
1919 << D.getSourceRange());
1920 if (Chunk.Arr.hasStatic)
1921 return ExprError(Diag(Loc: Chunk.Loc, DiagID: diag::err_static_illegal_in_new)
1922 << D.getSourceRange());
1923 if (!Chunk.Arr.NumElts && !Initializer)
1924 return ExprError(Diag(Loc: Chunk.Loc, DiagID: diag::err_array_new_needs_size)
1925 << D.getSourceRange());
1926
1927 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1928 D.DropFirstTypeObject();
1929 }
1930
1931 // Every dimension shall be of constant size.
1932 if (ArraySize) {
1933 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1934 if (D.getTypeObject(i: I).Kind != DeclaratorChunk::Array)
1935 break;
1936
1937 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(i: I).Arr;
1938 if (Expr *NumElts = (Expr *)Array.NumElts) {
1939 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1940 // FIXME: GCC permits constant folding here. We should either do so consistently
1941 // or not do so at all, rather than changing behavior in C++14 onwards.
1942 if (getLangOpts().CPlusPlus14) {
1943 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1944 // shall be a converted constant expression (5.19) of type std::size_t
1945 // and shall evaluate to a strictly positive value.
1946 llvm::APSInt Value(Context.getIntWidth(T: Context.getSizeType()));
1947 Array.NumElts
1948 = CheckConvertedConstantExpression(From: NumElts, T: Context.getSizeType(), Value,
1949 CCE: CCEK_ArrayBound)
1950 .get();
1951 } else {
1952 Array.NumElts =
1953 VerifyIntegerConstantExpression(
1954 E: NumElts, Result: nullptr, DiagID: diag::err_new_array_nonconst, CanFold: AllowFold)
1955 .get();
1956 }
1957 if (!Array.NumElts)
1958 return ExprError();
1959 }
1960 }
1961 }
1962 }
1963
1964 TypeSourceInfo *TInfo = GetTypeForDeclarator(D);
1965 QualType AllocType = TInfo->getType();
1966 if (D.isInvalidType())
1967 return ExprError();
1968
1969 SourceRange DirectInitRange;
1970 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Val: Initializer))
1971 DirectInitRange = List->getSourceRange();
1972
1973 return BuildCXXNew(Range: SourceRange(StartLoc, D.getEndLoc()), UseGlobal,
1974 PlacementLParen, PlacementArgs, PlacementRParen,
1975 TypeIdParens, AllocType, AllocTypeInfo: TInfo, ArraySize, DirectInitRange,
1976 Initializer);
1977}
1978
1979static bool isLegalArrayNewInitializer(CXXNewInitializationStyle Style,
1980 Expr *Init, bool IsCPlusPlus20) {
1981 if (!Init)
1982 return true;
1983 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Val: Init))
1984 return IsCPlusPlus20 || PLE->getNumExprs() == 0;
1985 if (isa<ImplicitValueInitExpr>(Val: Init))
1986 return true;
1987 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Val: Init))
1988 return !CCE->isListInitialization() &&
1989 CCE->getConstructor()->isDefaultConstructor();
1990 else if (Style == CXXNewInitializationStyle::Braces) {
1991 assert(isa<InitListExpr>(Init) &&
1992 "Shouldn't create list CXXConstructExprs for arrays.");
1993 return true;
1994 }
1995 return false;
1996}
1997
1998bool
1999Sema::isUnavailableAlignedAllocationFunction(const FunctionDecl &FD) const {
2000 if (!getLangOpts().AlignedAllocationUnavailable)
2001 return false;
2002 if (FD.isDefined())
2003 return false;
2004 std::optional<unsigned> AlignmentParam;
2005 if (FD.isReplaceableGlobalAllocationFunction(AlignmentParam: &AlignmentParam) &&
2006 AlignmentParam)
2007 return true;
2008 return false;
2009}
2010
2011// Emit a diagnostic if an aligned allocation/deallocation function that is not
2012// implemented in the standard library is selected.
2013void Sema::diagnoseUnavailableAlignedAllocation(const FunctionDecl &FD,
2014 SourceLocation Loc) {
2015 if (isUnavailableAlignedAllocationFunction(FD)) {
2016 const llvm::Triple &T = getASTContext().getTargetInfo().getTriple();
2017 StringRef OSName = AvailabilityAttr::getPlatformNameSourceSpelling(
2018 Platform: getASTContext().getTargetInfo().getPlatformName());
2019 VersionTuple OSVersion = alignedAllocMinVersion(OS: T.getOS());
2020
2021 OverloadedOperatorKind Kind = FD.getDeclName().getCXXOverloadedOperator();
2022 bool IsDelete = Kind == OO_Delete || Kind == OO_Array_Delete;
2023 Diag(Loc, DiagID: diag::err_aligned_allocation_unavailable)
2024 << IsDelete << FD.getType().getAsString() << OSName
2025 << OSVersion.getAsString() << OSVersion.empty();
2026 Diag(Loc, DiagID: diag::note_silence_aligned_allocation_unavailable);
2027 }
2028}
2029
2030ExprResult Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
2031 SourceLocation PlacementLParen,
2032 MultiExprArg PlacementArgs,
2033 SourceLocation PlacementRParen,
2034 SourceRange TypeIdParens, QualType AllocType,
2035 TypeSourceInfo *AllocTypeInfo,
2036 std::optional<Expr *> ArraySize,
2037 SourceRange DirectInitRange, Expr *Initializer) {
2038 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
2039 SourceLocation StartLoc = Range.getBegin();
2040
2041 CXXNewInitializationStyle InitStyle;
2042 if (DirectInitRange.isValid()) {
2043 assert(Initializer && "Have parens but no initializer.");
2044 InitStyle = CXXNewInitializationStyle::Parens;
2045 } else if (isa_and_nonnull<InitListExpr>(Val: Initializer))
2046 InitStyle = CXXNewInitializationStyle::Braces;
2047 else {
2048 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
2049 isa<CXXConstructExpr>(Initializer)) &&
2050 "Initializer expression that cannot have been implicitly created.");
2051 InitStyle = CXXNewInitializationStyle::None;
2052 }
2053
2054 MultiExprArg Exprs(&Initializer, Initializer ? 1 : 0);
2055 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Val: Initializer)) {
2056 assert(InitStyle == CXXNewInitializationStyle::Parens &&
2057 "paren init for non-call init");
2058 Exprs = MultiExprArg(List->getExprs(), List->getNumExprs());
2059 }
2060
2061 // C++11 [expr.new]p15:
2062 // A new-expression that creates an object of type T initializes that
2063 // object as follows:
2064 InitializationKind Kind = [&] {
2065 switch (InitStyle) {
2066 // - If the new-initializer is omitted, the object is default-
2067 // initialized (8.5); if no initialization is performed,
2068 // the object has indeterminate value
2069 case CXXNewInitializationStyle::None:
2070 return InitializationKind::CreateDefault(InitLoc: TypeRange.getBegin());
2071 // - Otherwise, the new-initializer is interpreted according to the
2072 // initialization rules of 8.5 for direct-initialization.
2073 case CXXNewInitializationStyle::Parens:
2074 return InitializationKind::CreateDirect(InitLoc: TypeRange.getBegin(),
2075 LParenLoc: DirectInitRange.getBegin(),
2076 RParenLoc: DirectInitRange.getEnd());
2077 case CXXNewInitializationStyle::Braces:
2078 return InitializationKind::CreateDirectList(InitLoc: TypeRange.getBegin(),
2079 LBraceLoc: Initializer->getBeginLoc(),
2080 RBraceLoc: Initializer->getEndLoc());
2081 }
2082 llvm_unreachable("Unknown initialization kind");
2083 }();
2084
2085 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
2086 auto *Deduced = AllocType->getContainedDeducedType();
2087 if (Deduced && !Deduced->isDeduced() &&
2088 isa<DeducedTemplateSpecializationType>(Val: Deduced)) {
2089 if (ArraySize)
2090 return ExprError(
2091 Diag(Loc: *ArraySize ? (*ArraySize)->getExprLoc() : TypeRange.getBegin(),
2092 DiagID: diag::err_deduced_class_template_compound_type)
2093 << /*array*/ 2
2094 << (*ArraySize ? (*ArraySize)->getSourceRange() : TypeRange));
2095
2096 InitializedEntity Entity
2097 = InitializedEntity::InitializeNew(NewLoc: StartLoc, Type: AllocType);
2098 AllocType = DeduceTemplateSpecializationFromInitializer(
2099 TInfo: AllocTypeInfo, Entity, Kind, Init: Exprs);
2100 if (AllocType.isNull())
2101 return ExprError();
2102 } else if (Deduced && !Deduced->isDeduced()) {
2103 MultiExprArg Inits = Exprs;
2104 bool Braced = (InitStyle == CXXNewInitializationStyle::Braces);
2105 if (Braced) {
2106 auto *ILE = cast<InitListExpr>(Val: Exprs[0]);
2107 Inits = MultiExprArg(ILE->getInits(), ILE->getNumInits());
2108 }
2109
2110 if (InitStyle == CXXNewInitializationStyle::None || Inits.empty())
2111 return ExprError(Diag(Loc: StartLoc, DiagID: diag::err_auto_new_requires_ctor_arg)
2112 << AllocType << TypeRange);
2113 if (Inits.size() > 1) {
2114 Expr *FirstBad = Inits[1];
2115 return ExprError(Diag(Loc: FirstBad->getBeginLoc(),
2116 DiagID: diag::err_auto_new_ctor_multiple_expressions)
2117 << AllocType << TypeRange);
2118 }
2119 if (Braced && !getLangOpts().CPlusPlus17)
2120 Diag(Loc: Initializer->getBeginLoc(), DiagID: diag::ext_auto_new_list_init)
2121 << AllocType << TypeRange;
2122 Expr *Deduce = Inits[0];
2123 if (isa<InitListExpr>(Val: Deduce))
2124 return ExprError(
2125 Diag(Loc: Deduce->getBeginLoc(), DiagID: diag::err_auto_expr_init_paren_braces)
2126 << Braced << AllocType << TypeRange);
2127 QualType DeducedType;
2128 TemplateDeductionInfo Info(Deduce->getExprLoc());
2129 TemplateDeductionResult Result =
2130 DeduceAutoType(AutoTypeLoc: AllocTypeInfo->getTypeLoc(), Initializer: Deduce, Result&: DeducedType, Info);
2131 if (Result != TemplateDeductionResult::Success &&
2132 Result != TemplateDeductionResult::AlreadyDiagnosed)
2133 return ExprError(Diag(Loc: StartLoc, DiagID: diag::err_auto_new_deduction_failure)
2134 << AllocType << Deduce->getType() << TypeRange
2135 << Deduce->getSourceRange());
2136 if (DeducedType.isNull()) {
2137 assert(Result == TemplateDeductionResult::AlreadyDiagnosed);
2138 return ExprError();
2139 }
2140 AllocType = DeducedType;
2141 }
2142
2143 // Per C++0x [expr.new]p5, the type being constructed may be a
2144 // typedef of an array type.
2145 if (!ArraySize) {
2146 if (const ConstantArrayType *Array
2147 = Context.getAsConstantArrayType(T: AllocType)) {
2148 ArraySize = IntegerLiteral::Create(C: Context, V: Array->getSize(),
2149 type: Context.getSizeType(),
2150 l: TypeRange.getEnd());
2151 AllocType = Array->getElementType();
2152 }
2153 }
2154
2155 if (CheckAllocatedType(AllocType, Loc: TypeRange.getBegin(), R: TypeRange))
2156 return ExprError();
2157
2158 if (ArraySize && !checkArrayElementAlignment(EltTy: AllocType, Loc: TypeRange.getBegin()))
2159 return ExprError();
2160
2161 // In ARC, infer 'retaining' for the allocated
2162 if (getLangOpts().ObjCAutoRefCount &&
2163 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2164 AllocType->isObjCLifetimeType()) {
2165 AllocType = Context.getLifetimeQualifiedType(type: AllocType,
2166 lifetime: AllocType->getObjCARCImplicitLifetime());
2167 }
2168
2169 QualType ResultType = Context.getPointerType(T: AllocType);
2170
2171 if (ArraySize && *ArraySize &&
2172 (*ArraySize)->getType()->isNonOverloadPlaceholderType()) {
2173 ExprResult result = CheckPlaceholderExpr(E: *ArraySize);
2174 if (result.isInvalid()) return ExprError();
2175 ArraySize = result.get();
2176 }
2177 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
2178 // integral or enumeration type with a non-negative value."
2179 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
2180 // enumeration type, or a class type for which a single non-explicit
2181 // conversion function to integral or unscoped enumeration type exists.
2182 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
2183 // std::size_t.
2184 std::optional<uint64_t> KnownArraySize;
2185 if (ArraySize && *ArraySize && !(*ArraySize)->isTypeDependent()) {
2186 ExprResult ConvertedSize;
2187 if (getLangOpts().CPlusPlus14) {
2188 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
2189
2190 ConvertedSize = PerformImplicitConversion(From: *ArraySize, ToType: Context.getSizeType(),
2191 Action: AA_Converting);
2192
2193 if (!ConvertedSize.isInvalid() &&
2194 (*ArraySize)->getType()->getAs<RecordType>())
2195 // Diagnose the compatibility of this conversion.
2196 Diag(Loc: StartLoc, DiagID: diag::warn_cxx98_compat_array_size_conversion)
2197 << (*ArraySize)->getType() << 0 << "'size_t'";
2198 } else {
2199 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
2200 protected:
2201 Expr *ArraySize;
2202
2203 public:
2204 SizeConvertDiagnoser(Expr *ArraySize)
2205 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
2206 ArraySize(ArraySize) {}
2207
2208 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
2209 QualType T) override {
2210 return S.Diag(Loc, DiagID: diag::err_array_size_not_integral)
2211 << S.getLangOpts().CPlusPlus11 << T;
2212 }
2213
2214 SemaDiagnosticBuilder diagnoseIncomplete(
2215 Sema &S, SourceLocation Loc, QualType T) override {
2216 return S.Diag(Loc, DiagID: diag::err_array_size_incomplete_type)
2217 << T << ArraySize->getSourceRange();
2218 }
2219
2220 SemaDiagnosticBuilder diagnoseExplicitConv(
2221 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
2222 return S.Diag(Loc, DiagID: diag::err_array_size_explicit_conversion) << T << ConvTy;
2223 }
2224
2225 SemaDiagnosticBuilder noteExplicitConv(
2226 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2227 return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_array_size_conversion)
2228 << ConvTy->isEnumeralType() << ConvTy;
2229 }
2230
2231 SemaDiagnosticBuilder diagnoseAmbiguous(
2232 Sema &S, SourceLocation Loc, QualType T) override {
2233 return S.Diag(Loc, DiagID: diag::err_array_size_ambiguous_conversion) << T;
2234 }
2235
2236 SemaDiagnosticBuilder noteAmbiguous(
2237 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2238 return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_array_size_conversion)
2239 << ConvTy->isEnumeralType() << ConvTy;
2240 }
2241
2242 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2243 QualType T,
2244 QualType ConvTy) override {
2245 return S.Diag(Loc,
2246 DiagID: S.getLangOpts().CPlusPlus11
2247 ? diag::warn_cxx98_compat_array_size_conversion
2248 : diag::ext_array_size_conversion)
2249 << T << ConvTy->isEnumeralType() << ConvTy;
2250 }
2251 } SizeDiagnoser(*ArraySize);
2252
2253 ConvertedSize = PerformContextualImplicitConversion(Loc: StartLoc, FromE: *ArraySize,
2254 Converter&: SizeDiagnoser);
2255 }
2256 if (ConvertedSize.isInvalid())
2257 return ExprError();
2258
2259 ArraySize = ConvertedSize.get();
2260 QualType SizeType = (*ArraySize)->getType();
2261
2262 if (!SizeType->isIntegralOrUnscopedEnumerationType())
2263 return ExprError();
2264
2265 // C++98 [expr.new]p7:
2266 // The expression in a direct-new-declarator shall have integral type
2267 // with a non-negative value.
2268 //
2269 // Let's see if this is a constant < 0. If so, we reject it out of hand,
2270 // per CWG1464. Otherwise, if it's not a constant, we must have an
2271 // unparenthesized array type.
2272
2273 // We've already performed any required implicit conversion to integer or
2274 // unscoped enumeration type.
2275 // FIXME: Per CWG1464, we are required to check the value prior to
2276 // converting to size_t. This will never find a negative array size in
2277 // C++14 onwards, because Value is always unsigned here!
2278 if (std::optional<llvm::APSInt> Value =
2279 (*ArraySize)->getIntegerConstantExpr(Ctx: Context)) {
2280 if (Value->isSigned() && Value->isNegative()) {
2281 return ExprError(Diag(Loc: (*ArraySize)->getBeginLoc(),
2282 DiagID: diag::err_typecheck_negative_array_size)
2283 << (*ArraySize)->getSourceRange());
2284 }
2285
2286 if (!AllocType->isDependentType()) {
2287 unsigned ActiveSizeBits =
2288 ConstantArrayType::getNumAddressingBits(Context, ElementType: AllocType, NumElements: *Value);
2289 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
2290 return ExprError(
2291 Diag(Loc: (*ArraySize)->getBeginLoc(), DiagID: diag::err_array_too_large)
2292 << toString(I: *Value, Radix: 10) << (*ArraySize)->getSourceRange());
2293 }
2294
2295 KnownArraySize = Value->getZExtValue();
2296 } else if (TypeIdParens.isValid()) {
2297 // Can't have dynamic array size when the type-id is in parentheses.
2298 Diag(Loc: (*ArraySize)->getBeginLoc(), DiagID: diag::ext_new_paren_array_nonconst)
2299 << (*ArraySize)->getSourceRange()
2300 << FixItHint::CreateRemoval(RemoveRange: TypeIdParens.getBegin())
2301 << FixItHint::CreateRemoval(RemoveRange: TypeIdParens.getEnd());
2302
2303 TypeIdParens = SourceRange();
2304 }
2305
2306 // Note that we do *not* convert the argument in any way. It can
2307 // be signed, larger than size_t, whatever.
2308 }
2309
2310 FunctionDecl *OperatorNew = nullptr;
2311 FunctionDecl *OperatorDelete = nullptr;
2312 unsigned Alignment =
2313 AllocType->isDependentType() ? 0 : Context.getTypeAlign(T: AllocType);
2314 unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
2315 bool PassAlignment = getLangOpts().AlignedAllocation &&
2316 Alignment > NewAlignment;
2317
2318 if (CheckArgsForPlaceholders(args: PlacementArgs))
2319 return ExprError();
2320
2321 AllocationFunctionScope Scope = UseGlobal ? AFS_Global : AFS_Both;
2322 if (!AllocType->isDependentType() &&
2323 !Expr::hasAnyTypeDependentArguments(Exprs: PlacementArgs) &&
2324 FindAllocationFunctions(
2325 StartLoc, Range: SourceRange(PlacementLParen, PlacementRParen), NewScope: Scope, DeleteScope: Scope,
2326 AllocType, IsArray: ArraySize.has_value(), PassAlignment, PlaceArgs: PlacementArgs,
2327 OperatorNew, OperatorDelete))
2328 return ExprError();
2329
2330 // If this is an array allocation, compute whether the usual array
2331 // deallocation function for the type has a size_t parameter.
2332 bool UsualArrayDeleteWantsSize = false;
2333 if (ArraySize && !AllocType->isDependentType())
2334 UsualArrayDeleteWantsSize =
2335 doesUsualArrayDeleteWantSize(S&: *this, loc: StartLoc, allocType: AllocType);
2336
2337 SmallVector<Expr *, 8> AllPlaceArgs;
2338 if (OperatorNew) {
2339 auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2340 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
2341 : VariadicDoesNotApply;
2342
2343 // We've already converted the placement args, just fill in any default
2344 // arguments. Skip the first parameter because we don't have a corresponding
2345 // argument. Skip the second parameter too if we're passing in the
2346 // alignment; we've already filled it in.
2347 unsigned NumImplicitArgs = PassAlignment ? 2 : 1;
2348 if (GatherArgumentsForCall(CallLoc: PlacementLParen, FDecl: OperatorNew, Proto,
2349 FirstParam: NumImplicitArgs, Args: PlacementArgs, AllArgs&: AllPlaceArgs,
2350 CallType))
2351 return ExprError();
2352
2353 if (!AllPlaceArgs.empty())
2354 PlacementArgs = AllPlaceArgs;
2355
2356 // We would like to perform some checking on the given `operator new` call,
2357 // but the PlacementArgs does not contain the implicit arguments,
2358 // namely allocation size and maybe allocation alignment,
2359 // so we need to conjure them.
2360
2361 QualType SizeTy = Context.getSizeType();
2362 unsigned SizeTyWidth = Context.getTypeSize(T: SizeTy);
2363
2364 llvm::APInt SingleEltSize(
2365 SizeTyWidth, Context.getTypeSizeInChars(T: AllocType).getQuantity());
2366
2367 // How many bytes do we want to allocate here?
2368 std::optional<llvm::APInt> AllocationSize;
2369 if (!ArraySize && !AllocType->isDependentType()) {
2370 // For non-array operator new, we only want to allocate one element.
2371 AllocationSize = SingleEltSize;
2372 } else if (KnownArraySize && !AllocType->isDependentType()) {
2373 // For array operator new, only deal with static array size case.
2374 bool Overflow;
2375 AllocationSize = llvm::APInt(SizeTyWidth, *KnownArraySize)
2376 .umul_ov(RHS: SingleEltSize, Overflow);
2377 (void)Overflow;
2378 assert(
2379 !Overflow &&
2380 "Expected that all the overflows would have been handled already.");
2381 }
2382
2383 IntegerLiteral AllocationSizeLiteral(
2384 Context, AllocationSize.value_or(u: llvm::APInt::getZero(numBits: SizeTyWidth)),
2385 SizeTy, SourceLocation());
2386 // Otherwise, if we failed to constant-fold the allocation size, we'll
2387 // just give up and pass-in something opaque, that isn't a null pointer.
2388 OpaqueValueExpr OpaqueAllocationSize(SourceLocation(), SizeTy, VK_PRValue,
2389 OK_Ordinary, /*SourceExpr=*/nullptr);
2390
2391 // Let's synthesize the alignment argument in case we will need it.
2392 // Since we *really* want to allocate these on stack, this is slightly ugly
2393 // because there might not be a `std::align_val_t` type.
2394 EnumDecl *StdAlignValT = getStdAlignValT();
2395 QualType AlignValT =
2396 StdAlignValT ? Context.getTypeDeclType(Decl: StdAlignValT) : SizeTy;
2397 IntegerLiteral AlignmentLiteral(
2398 Context,
2399 llvm::APInt(Context.getTypeSize(T: SizeTy),
2400 Alignment / Context.getCharWidth()),
2401 SizeTy, SourceLocation());
2402 ImplicitCastExpr DesiredAlignment(ImplicitCastExpr::OnStack, AlignValT,
2403 CK_IntegralCast, &AlignmentLiteral,
2404 VK_PRValue, FPOptionsOverride());
2405
2406 // Adjust placement args by prepending conjured size and alignment exprs.
2407 llvm::SmallVector<Expr *, 8> CallArgs;
2408 CallArgs.reserve(N: NumImplicitArgs + PlacementArgs.size());
2409 CallArgs.emplace_back(Args: AllocationSize
2410 ? static_cast<Expr *>(&AllocationSizeLiteral)
2411 : &OpaqueAllocationSize);
2412 if (PassAlignment)
2413 CallArgs.emplace_back(Args: &DesiredAlignment);
2414 CallArgs.insert(I: CallArgs.end(), From: PlacementArgs.begin(), To: PlacementArgs.end());
2415
2416 DiagnoseSentinelCalls(D: OperatorNew, Loc: PlacementLParen, Args: CallArgs);
2417
2418 checkCall(FDecl: OperatorNew, Proto, /*ThisArg=*/nullptr, Args: CallArgs,
2419 /*IsMemberFunction=*/false, Loc: StartLoc, Range, CallType);
2420
2421 // Warn if the type is over-aligned and is being allocated by (unaligned)
2422 // global operator new.
2423 if (PlacementArgs.empty() && !PassAlignment &&
2424 (OperatorNew->isImplicit() ||
2425 (OperatorNew->getBeginLoc().isValid() &&
2426 getSourceManager().isInSystemHeader(Loc: OperatorNew->getBeginLoc())))) {
2427 if (Alignment > NewAlignment)
2428 Diag(Loc: StartLoc, DiagID: diag::warn_overaligned_type)
2429 << AllocType
2430 << unsigned(Alignment / Context.getCharWidth())
2431 << unsigned(NewAlignment / Context.getCharWidth());
2432 }
2433 }
2434
2435 // Array 'new' can't have any initializers except empty parentheses.
2436 // Initializer lists are also allowed, in C++11. Rely on the parser for the
2437 // dialect distinction.
2438 if (ArraySize && !isLegalArrayNewInitializer(Style: InitStyle, Init: Initializer,
2439 IsCPlusPlus20: getLangOpts().CPlusPlus20)) {
2440 SourceRange InitRange(Exprs.front()->getBeginLoc(),
2441 Exprs.back()->getEndLoc());
2442 Diag(Loc: StartLoc, DiagID: diag::err_new_array_init_args) << InitRange;
2443 return ExprError();
2444 }
2445
2446 // If we can perform the initialization, and we've not already done so,
2447 // do it now.
2448 if (!AllocType->isDependentType() &&
2449 !Expr::hasAnyTypeDependentArguments(Exprs)) {
2450 // The type we initialize is the complete type, including the array bound.
2451 QualType InitType;
2452 if (KnownArraySize)
2453 InitType = Context.getConstantArrayType(
2454 EltTy: AllocType,
2455 ArySize: llvm::APInt(Context.getTypeSize(T: Context.getSizeType()),
2456 *KnownArraySize),
2457 SizeExpr: *ArraySize, ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
2458 else if (ArraySize)
2459 InitType = Context.getIncompleteArrayType(EltTy: AllocType,
2460 ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
2461 else
2462 InitType = AllocType;
2463
2464 InitializedEntity Entity
2465 = InitializedEntity::InitializeNew(NewLoc: StartLoc, Type: InitType);
2466 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
2467 ExprResult FullInit = InitSeq.Perform(S&: *this, Entity, Kind, Args: Exprs);
2468 if (FullInit.isInvalid())
2469 return ExprError();
2470
2471 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
2472 // we don't want the initialized object to be destructed.
2473 // FIXME: We should not create these in the first place.
2474 if (CXXBindTemporaryExpr *Binder =
2475 dyn_cast_or_null<CXXBindTemporaryExpr>(Val: FullInit.get()))
2476 FullInit = Binder->getSubExpr();
2477
2478 Initializer = FullInit.get();
2479
2480 // FIXME: If we have a KnownArraySize, check that the array bound of the
2481 // initializer is no greater than that constant value.
2482
2483 if (ArraySize && !*ArraySize) {
2484 auto *CAT = Context.getAsConstantArrayType(T: Initializer->getType());
2485 if (CAT) {
2486 // FIXME: Track that the array size was inferred rather than explicitly
2487 // specified.
2488 ArraySize = IntegerLiteral::Create(
2489 C: Context, V: CAT->getSize(), type: Context.getSizeType(), l: TypeRange.getEnd());
2490 } else {
2491 Diag(Loc: TypeRange.getEnd(), DiagID: diag::err_new_array_size_unknown_from_init)
2492 << Initializer->getSourceRange();
2493 }
2494 }
2495 }
2496
2497 // Mark the new and delete operators as referenced.
2498 if (OperatorNew) {
2499 if (DiagnoseUseOfDecl(D: OperatorNew, Locs: StartLoc))
2500 return ExprError();
2501 MarkFunctionReferenced(Loc: StartLoc, Func: OperatorNew);
2502 }
2503 if (OperatorDelete) {
2504 if (DiagnoseUseOfDecl(D: OperatorDelete, Locs: StartLoc))
2505 return ExprError();
2506 MarkFunctionReferenced(Loc: StartLoc, Func: OperatorDelete);
2507 }
2508
2509 return CXXNewExpr::Create(Ctx: Context, IsGlobalNew: UseGlobal, OperatorNew, OperatorDelete,
2510 ShouldPassAlignment: PassAlignment, UsualArrayDeleteWantsSize,
2511 PlacementArgs, TypeIdParens, ArraySize, InitializationStyle: InitStyle,
2512 Initializer, Ty: ResultType, AllocatedTypeInfo: AllocTypeInfo, Range,
2513 DirectInitRange);
2514}
2515
2516bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
2517 SourceRange R) {
2518 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2519 // abstract class type or array thereof.
2520 if (AllocType->isFunctionType())
2521 return Diag(Loc, DiagID: diag::err_bad_new_type)
2522 << AllocType << 0 << R;
2523 else if (AllocType->isReferenceType())
2524 return Diag(Loc, DiagID: diag::err_bad_new_type)
2525 << AllocType << 1 << R;
2526 else if (!AllocType->isDependentType() &&
2527 RequireCompleteSizedType(
2528 Loc, T: AllocType, DiagID: diag::err_new_incomplete_or_sizeless_type, Args: R))
2529 return true;
2530 else if (RequireNonAbstractType(Loc, T: AllocType,
2531 DiagID: diag::err_allocation_of_abstract_type))
2532 return true;
2533 else if (AllocType->isVariablyModifiedType())
2534 return Diag(Loc, DiagID: diag::err_variably_modified_new_type)
2535 << AllocType;
2536 else if (AllocType.getAddressSpace() != LangAS::Default &&
2537 !getLangOpts().OpenCLCPlusPlus)
2538 return Diag(Loc, DiagID: diag::err_address_space_qualified_new)
2539 << AllocType.getUnqualifiedType()
2540 << AllocType.getQualifiers().getAddressSpaceAttributePrintValue();
2541 else if (getLangOpts().ObjCAutoRefCount) {
2542 if (const ArrayType *AT = Context.getAsArrayType(T: AllocType)) {
2543 QualType BaseAllocType = Context.getBaseElementType(VAT: AT);
2544 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2545 BaseAllocType->isObjCLifetimeType())
2546 return Diag(Loc, DiagID: diag::err_arc_new_array_without_ownership)
2547 << BaseAllocType;
2548 }
2549 }
2550
2551 return false;
2552}
2553
2554static bool resolveAllocationOverload(
2555 Sema &S, LookupResult &R, SourceRange Range, SmallVectorImpl<Expr *> &Args,
2556 bool &PassAlignment, FunctionDecl *&Operator,
2557 OverloadCandidateSet *AlignedCandidates, Expr *AlignArg, bool Diagnose) {
2558 OverloadCandidateSet Candidates(R.getNameLoc(),
2559 OverloadCandidateSet::CSK_Normal);
2560 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2561 Alloc != AllocEnd; ++Alloc) {
2562 // Even member operator new/delete are implicitly treated as
2563 // static, so don't use AddMemberCandidate.
2564 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2565
2566 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(Val: D)) {
2567 S.AddTemplateOverloadCandidate(FunctionTemplate: FnTemplate, FoundDecl: Alloc.getPair(),
2568 /*ExplicitTemplateArgs=*/nullptr, Args,
2569 CandidateSet&: Candidates,
2570 /*SuppressUserConversions=*/false);
2571 continue;
2572 }
2573
2574 FunctionDecl *Fn = cast<FunctionDecl>(Val: D);
2575 S.AddOverloadCandidate(Function: Fn, FoundDecl: Alloc.getPair(), Args, CandidateSet&: Candidates,
2576 /*SuppressUserConversions=*/false);
2577 }
2578
2579 // Do the resolution.
2580 OverloadCandidateSet::iterator Best;
2581 switch (Candidates.BestViableFunction(S, Loc: R.getNameLoc(), Best)) {
2582 case OR_Success: {
2583 // Got one!
2584 FunctionDecl *FnDecl = Best->Function;
2585 if (S.CheckAllocationAccess(OperatorLoc: R.getNameLoc(), PlacementRange: Range, NamingClass: R.getNamingClass(),
2586 FoundDecl: Best->FoundDecl) == Sema::AR_inaccessible)
2587 return true;
2588
2589 Operator = FnDecl;
2590 return false;
2591 }
2592
2593 case OR_No_Viable_Function:
2594 // C++17 [expr.new]p13:
2595 // If no matching function is found and the allocated object type has
2596 // new-extended alignment, the alignment argument is removed from the
2597 // argument list, and overload resolution is performed again.
2598 if (PassAlignment) {
2599 PassAlignment = false;
2600 AlignArg = Args[1];
2601 Args.erase(CI: Args.begin() + 1);
2602 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2603 Operator, AlignedCandidates: &Candidates, AlignArg,
2604 Diagnose);
2605 }
2606
2607 // MSVC will fall back on trying to find a matching global operator new
2608 // if operator new[] cannot be found. Also, MSVC will leak by not
2609 // generating a call to operator delete or operator delete[], but we
2610 // will not replicate that bug.
2611 // FIXME: Find out how this interacts with the std::align_val_t fallback
2612 // once MSVC implements it.
2613 if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2614 S.Context.getLangOpts().MSVCCompat) {
2615 R.clear();
2616 R.setLookupName(S.Context.DeclarationNames.getCXXOperatorName(Op: OO_New));
2617 S.LookupQualifiedName(R, LookupCtx: S.Context.getTranslationUnitDecl());
2618 // FIXME: This will give bad diagnostics pointing at the wrong functions.
2619 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2620 Operator, /*Candidates=*/AlignedCandidates: nullptr,
2621 /*AlignArg=*/nullptr, Diagnose);
2622 }
2623
2624 if (Diagnose) {
2625 // If this is an allocation of the form 'new (p) X' for some object
2626 // pointer p (or an expression that will decay to such a pointer),
2627 // diagnose the missing inclusion of <new>.
2628 if (!R.isClassLookup() && Args.size() == 2 &&
2629 (Args[1]->getType()->isObjectPointerType() ||
2630 Args[1]->getType()->isArrayType())) {
2631 S.Diag(Loc: R.getNameLoc(), DiagID: diag::err_need_header_before_placement_new)
2632 << R.getLookupName() << Range;
2633 // Listing the candidates is unlikely to be useful; skip it.
2634 return true;
2635 }
2636
2637 // Finish checking all candidates before we note any. This checking can
2638 // produce additional diagnostics so can't be interleaved with our
2639 // emission of notes.
2640 //
2641 // For an aligned allocation, separately check the aligned and unaligned
2642 // candidates with their respective argument lists.
2643 SmallVector<OverloadCandidate*, 32> Cands;
2644 SmallVector<OverloadCandidate*, 32> AlignedCands;
2645 llvm::SmallVector<Expr*, 4> AlignedArgs;
2646 if (AlignedCandidates) {
2647 auto IsAligned = [](OverloadCandidate &C) {
2648 return C.Function->getNumParams() > 1 &&
2649 C.Function->getParamDecl(i: 1)->getType()->isAlignValT();
2650 };
2651 auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2652
2653 AlignedArgs.reserve(N: Args.size() + 1);
2654 AlignedArgs.push_back(Elt: Args[0]);
2655 AlignedArgs.push_back(Elt: AlignArg);
2656 AlignedArgs.append(in_start: Args.begin() + 1, in_end: Args.end());
2657 AlignedCands = AlignedCandidates->CompleteCandidates(
2658 S, OCD: OCD_AllCandidates, Args: AlignedArgs, OpLoc: R.getNameLoc(), Filter: IsAligned);
2659
2660 Cands = Candidates.CompleteCandidates(S, OCD: OCD_AllCandidates, Args,
2661 OpLoc: R.getNameLoc(), Filter: IsUnaligned);
2662 } else {
2663 Cands = Candidates.CompleteCandidates(S, OCD: OCD_AllCandidates, Args,
2664 OpLoc: R.getNameLoc());
2665 }
2666
2667 S.Diag(Loc: R.getNameLoc(), DiagID: diag::err_ovl_no_viable_function_in_call)
2668 << R.getLookupName() << Range;
2669 if (AlignedCandidates)
2670 AlignedCandidates->NoteCandidates(S, Args: AlignedArgs, Cands: AlignedCands, Opc: "",
2671 OpLoc: R.getNameLoc());
2672 Candidates.NoteCandidates(S, Args, Cands, Opc: "", OpLoc: R.getNameLoc());
2673 }
2674 return true;
2675
2676 case OR_Ambiguous:
2677 if (Diagnose) {
2678 Candidates.NoteCandidates(
2679 PA: PartialDiagnosticAt(R.getNameLoc(),
2680 S.PDiag(DiagID: diag::err_ovl_ambiguous_call)
2681 << R.getLookupName() << Range),
2682 S, OCD: OCD_AmbiguousCandidates, Args);
2683 }
2684 return true;
2685
2686 case OR_Deleted: {
2687 if (Diagnose)
2688 S.DiagnoseUseOfDeletedFunction(Loc: R.getNameLoc(), Range, Name: R.getLookupName(),
2689 CandidateSet&: Candidates, Fn: Best->Function, Args);
2690 return true;
2691 }
2692 }
2693 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2694}
2695
2696bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
2697 AllocationFunctionScope NewScope,
2698 AllocationFunctionScope DeleteScope,
2699 QualType AllocType, bool IsArray,
2700 bool &PassAlignment, MultiExprArg PlaceArgs,
2701 FunctionDecl *&OperatorNew,
2702 FunctionDecl *&OperatorDelete,
2703 bool Diagnose) {
2704 // --- Choosing an allocation function ---
2705 // C++ 5.3.4p8 - 14 & 18
2706 // 1) If looking in AFS_Global scope for allocation functions, only look in
2707 // the global scope. Else, if AFS_Class, only look in the scope of the
2708 // allocated class. If AFS_Both, look in both.
2709 // 2) If an array size is given, look for operator new[], else look for
2710 // operator new.
2711 // 3) The first argument is always size_t. Append the arguments from the
2712 // placement form.
2713
2714 SmallVector<Expr*, 8> AllocArgs;
2715 AllocArgs.reserve(N: (PassAlignment ? 2 : 1) + PlaceArgs.size());
2716
2717 // We don't care about the actual value of these arguments.
2718 // FIXME: Should the Sema create the expression and embed it in the syntax
2719 // tree? Or should the consumer just recalculate the value?
2720 // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2721 QualType SizeTy = Context.getSizeType();
2722 unsigned SizeTyWidth = Context.getTypeSize(T: SizeTy);
2723 IntegerLiteral Size(Context, llvm::APInt::getZero(numBits: SizeTyWidth), SizeTy,
2724 SourceLocation());
2725 AllocArgs.push_back(Elt: &Size);
2726
2727 QualType AlignValT = Context.VoidTy;
2728 if (PassAlignment) {
2729 DeclareGlobalNewDelete();
2730 AlignValT = Context.getTypeDeclType(Decl: getStdAlignValT());
2731 }
2732 CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2733 if (PassAlignment)
2734 AllocArgs.push_back(Elt: &Align);
2735
2736 AllocArgs.insert(I: AllocArgs.end(), From: PlaceArgs.begin(), To: PlaceArgs.end());
2737
2738 // C++ [expr.new]p8:
2739 // If the allocated type is a non-array type, the allocation
2740 // function's name is operator new and the deallocation function's
2741 // name is operator delete. If the allocated type is an array
2742 // type, the allocation function's name is operator new[] and the
2743 // deallocation function's name is operator delete[].
2744 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
2745 Op: IsArray ? OO_Array_New : OO_New);
2746
2747 QualType AllocElemType = Context.getBaseElementType(QT: AllocType);
2748
2749 // Find the allocation function.
2750 {
2751 LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2752
2753 // C++1z [expr.new]p9:
2754 // If the new-expression begins with a unary :: operator, the allocation
2755 // function's name is looked up in the global scope. Otherwise, if the
2756 // allocated type is a class type T or array thereof, the allocation
2757 // function's name is looked up in the scope of T.
2758 if (AllocElemType->isRecordType() && NewScope != AFS_Global)
2759 LookupQualifiedName(R, LookupCtx: AllocElemType->getAsCXXRecordDecl());
2760
2761 // We can see ambiguity here if the allocation function is found in
2762 // multiple base classes.
2763 if (R.isAmbiguous())
2764 return true;
2765
2766 // If this lookup fails to find the name, or if the allocated type is not
2767 // a class type, the allocation function's name is looked up in the
2768 // global scope.
2769 if (R.empty()) {
2770 if (NewScope == AFS_Class)
2771 return true;
2772
2773 LookupQualifiedName(R, LookupCtx: Context.getTranslationUnitDecl());
2774 }
2775
2776 if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
2777 if (PlaceArgs.empty()) {
2778 Diag(Loc: StartLoc, DiagID: diag::err_openclcxx_not_supported) << "default new";
2779 } else {
2780 Diag(Loc: StartLoc, DiagID: diag::err_openclcxx_placement_new);
2781 }
2782 return true;
2783 }
2784
2785 assert(!R.empty() && "implicitly declared allocation functions not found");
2786 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2787
2788 // We do our own custom access checks below.
2789 R.suppressDiagnostics();
2790
2791 if (resolveAllocationOverload(S&: *this, R, Range, Args&: AllocArgs, PassAlignment,
2792 Operator&: OperatorNew, /*Candidates=*/AlignedCandidates: nullptr,
2793 /*AlignArg=*/nullptr, Diagnose))
2794 return true;
2795 }
2796
2797 // We don't need an operator delete if we're running under -fno-exceptions.
2798 if (!getLangOpts().Exceptions) {
2799 OperatorDelete = nullptr;
2800 return false;
2801 }
2802
2803 // Note, the name of OperatorNew might have been changed from array to
2804 // non-array by resolveAllocationOverload.
2805 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2806 Op: OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2807 ? OO_Array_Delete
2808 : OO_Delete);
2809
2810 // C++ [expr.new]p19:
2811 //
2812 // If the new-expression begins with a unary :: operator, the
2813 // deallocation function's name is looked up in the global
2814 // scope. Otherwise, if the allocated type is a class type T or an
2815 // array thereof, the deallocation function's name is looked up in
2816 // the scope of T. If this lookup fails to find the name, or if
2817 // the allocated type is not a class type or array thereof, the
2818 // deallocation function's name is looked up in the global scope.
2819 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2820 if (AllocElemType->isRecordType() && DeleteScope != AFS_Global) {
2821 auto *RD =
2822 cast<CXXRecordDecl>(Val: AllocElemType->castAs<RecordType>()->getDecl());
2823 LookupQualifiedName(R&: FoundDelete, LookupCtx: RD);
2824 }
2825 if (FoundDelete.isAmbiguous())
2826 return true; // FIXME: clean up expressions?
2827
2828 // Filter out any destroying operator deletes. We can't possibly call such a
2829 // function in this context, because we're handling the case where the object
2830 // was not successfully constructed.
2831 // FIXME: This is not covered by the language rules yet.
2832 {
2833 LookupResult::Filter Filter = FoundDelete.makeFilter();
2834 while (Filter.hasNext()) {
2835 auto *FD = dyn_cast<FunctionDecl>(Val: Filter.next()->getUnderlyingDecl());
2836 if (FD && FD->isDestroyingOperatorDelete())
2837 Filter.erase();
2838 }
2839 Filter.done();
2840 }
2841
2842 bool FoundGlobalDelete = FoundDelete.empty();
2843 if (FoundDelete.empty()) {
2844 FoundDelete.clear(Kind: LookupOrdinaryName);
2845
2846 if (DeleteScope == AFS_Class)
2847 return true;
2848
2849 DeclareGlobalNewDelete();
2850 LookupQualifiedName(R&: FoundDelete, LookupCtx: Context.getTranslationUnitDecl());
2851 }
2852
2853 FoundDelete.suppressDiagnostics();
2854
2855 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2856
2857 // Whether we're looking for a placement operator delete is dictated
2858 // by whether we selected a placement operator new, not by whether
2859 // we had explicit placement arguments. This matters for things like
2860 // struct A { void *operator new(size_t, int = 0); ... };
2861 // A *a = new A()
2862 //
2863 // We don't have any definition for what a "placement allocation function"
2864 // is, but we assume it's any allocation function whose
2865 // parameter-declaration-clause is anything other than (size_t).
2866 //
2867 // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2868 // This affects whether an exception from the constructor of an overaligned
2869 // type uses the sized or non-sized form of aligned operator delete.
2870 bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2871 OperatorNew->isVariadic();
2872
2873 if (isPlacementNew) {
2874 // C++ [expr.new]p20:
2875 // A declaration of a placement deallocation function matches the
2876 // declaration of a placement allocation function if it has the
2877 // same number of parameters and, after parameter transformations
2878 // (8.3.5), all parameter types except the first are
2879 // identical. [...]
2880 //
2881 // To perform this comparison, we compute the function type that
2882 // the deallocation function should have, and use that type both
2883 // for template argument deduction and for comparison purposes.
2884 QualType ExpectedFunctionType;
2885 {
2886 auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2887
2888 SmallVector<QualType, 4> ArgTypes;
2889 ArgTypes.push_back(Elt: Context.VoidPtrTy);
2890 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2891 ArgTypes.push_back(Elt: Proto->getParamType(i: I));
2892
2893 FunctionProtoType::ExtProtoInfo EPI;
2894 // FIXME: This is not part of the standard's rule.
2895 EPI.Variadic = Proto->isVariadic();
2896
2897 ExpectedFunctionType
2898 = Context.getFunctionType(ResultTy: Context.VoidTy, Args: ArgTypes, EPI);
2899 }
2900
2901 for (LookupResult::iterator D = FoundDelete.begin(),
2902 DEnd = FoundDelete.end();
2903 D != DEnd; ++D) {
2904 FunctionDecl *Fn = nullptr;
2905 if (FunctionTemplateDecl *FnTmpl =
2906 dyn_cast<FunctionTemplateDecl>(Val: (*D)->getUnderlyingDecl())) {
2907 // Perform template argument deduction to try to match the
2908 // expected function type.
2909 TemplateDeductionInfo Info(StartLoc);
2910 if (DeduceTemplateArguments(FunctionTemplate: FnTmpl, ExplicitTemplateArgs: nullptr, ArgFunctionType: ExpectedFunctionType, Specialization&: Fn,
2911 Info) != TemplateDeductionResult::Success)
2912 continue;
2913 } else
2914 Fn = cast<FunctionDecl>(Val: (*D)->getUnderlyingDecl());
2915
2916 if (Context.hasSameType(T1: adjustCCAndNoReturn(ArgFunctionType: Fn->getType(),
2917 FunctionType: ExpectedFunctionType,
2918 /*AdjustExcpetionSpec*/AdjustExceptionSpec: true),
2919 T2: ExpectedFunctionType))
2920 Matches.push_back(Elt: std::make_pair(x: D.getPair(), y&: Fn));
2921 }
2922
2923 if (getLangOpts().CUDA)
2924 CUDA().EraseUnwantedMatches(Caller: getCurFunctionDecl(/*AllowLambda=*/true),
2925 Matches);
2926 } else {
2927 // C++1y [expr.new]p22:
2928 // For a non-placement allocation function, the normal deallocation
2929 // function lookup is used
2930 //
2931 // Per [expr.delete]p10, this lookup prefers a member operator delete
2932 // without a size_t argument, but prefers a non-member operator delete
2933 // with a size_t where possible (which it always is in this case).
2934 llvm::SmallVector<UsualDeallocFnInfo, 4> BestDeallocFns;
2935 UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2936 S&: *this, R&: FoundDelete, /*WantSize*/ FoundGlobalDelete,
2937 /*WantAlign*/ hasNewExtendedAlignment(S&: *this, AllocType: AllocElemType),
2938 BestFns: &BestDeallocFns);
2939 if (Selected)
2940 Matches.push_back(Elt: std::make_pair(x&: Selected.Found, y&: Selected.FD));
2941 else {
2942 // If we failed to select an operator, all remaining functions are viable
2943 // but ambiguous.
2944 for (auto Fn : BestDeallocFns)
2945 Matches.push_back(Elt: std::make_pair(x&: Fn.Found, y&: Fn.FD));
2946 }
2947 }
2948
2949 // C++ [expr.new]p20:
2950 // [...] If the lookup finds a single matching deallocation
2951 // function, that function will be called; otherwise, no
2952 // deallocation function will be called.
2953 if (Matches.size() == 1) {
2954 OperatorDelete = Matches[0].second;
2955
2956 // C++1z [expr.new]p23:
2957 // If the lookup finds a usual deallocation function (3.7.4.2)
2958 // with a parameter of type std::size_t and that function, considered
2959 // as a placement deallocation function, would have been
2960 // selected as a match for the allocation function, the program
2961 // is ill-formed.
2962 if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2963 isNonPlacementDeallocationFunction(S&: *this, FD: OperatorDelete)) {
2964 UsualDeallocFnInfo Info(*this,
2965 DeclAccessPair::make(D: OperatorDelete, AS: AS_public));
2966 // Core issue, per mail to core reflector, 2016-10-09:
2967 // If this is a member operator delete, and there is a corresponding
2968 // non-sized member operator delete, this isn't /really/ a sized
2969 // deallocation function, it just happens to have a size_t parameter.
2970 bool IsSizedDelete = Info.HasSizeT;
2971 if (IsSizedDelete && !FoundGlobalDelete) {
2972 auto NonSizedDelete =
2973 resolveDeallocationOverload(S&: *this, R&: FoundDelete, /*WantSize*/false,
2974 /*WantAlign*/Info.HasAlignValT);
2975 if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2976 NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2977 IsSizedDelete = false;
2978 }
2979
2980 if (IsSizedDelete) {
2981 SourceRange R = PlaceArgs.empty()
2982 ? SourceRange()
2983 : SourceRange(PlaceArgs.front()->getBeginLoc(),
2984 PlaceArgs.back()->getEndLoc());
2985 Diag(Loc: StartLoc, DiagID: diag::err_placement_new_non_placement_delete) << R;
2986 if (!OperatorDelete->isImplicit())
2987 Diag(Loc: OperatorDelete->getLocation(), DiagID: diag::note_previous_decl)
2988 << DeleteName;
2989 }
2990 }
2991
2992 CheckAllocationAccess(OperatorLoc: StartLoc, PlacementRange: Range, NamingClass: FoundDelete.getNamingClass(),
2993 FoundDecl: Matches[0].first);
2994 } else if (!Matches.empty()) {
2995 // We found multiple suitable operators. Per [expr.new]p20, that means we
2996 // call no 'operator delete' function, but we should at least warn the user.
2997 // FIXME: Suppress this warning if the construction cannot throw.
2998 Diag(Loc: StartLoc, DiagID: diag::warn_ambiguous_suitable_delete_function_found)
2999 << DeleteName << AllocElemType;
3000
3001 for (auto &Match : Matches)
3002 Diag(Loc: Match.second->getLocation(),
3003 DiagID: diag::note_member_declared_here) << DeleteName;
3004 }
3005
3006 return false;
3007}
3008
3009void Sema::DeclareGlobalNewDelete() {
3010 if (GlobalNewDeleteDeclared)
3011 return;
3012
3013 // The implicitly declared new and delete operators
3014 // are not supported in OpenCL.
3015 if (getLangOpts().OpenCLCPlusPlus)
3016 return;
3017
3018 // C++ [basic.stc.dynamic.general]p2:
3019 // The library provides default definitions for the global allocation
3020 // and deallocation functions. Some global allocation and deallocation
3021 // functions are replaceable ([new.delete]); these are attached to the
3022 // global module ([module.unit]).
3023 if (getLangOpts().CPlusPlusModules && getCurrentModule())
3024 PushGlobalModuleFragment(BeginLoc: SourceLocation());
3025
3026 // C++ [basic.std.dynamic]p2:
3027 // [...] The following allocation and deallocation functions (18.4) are
3028 // implicitly declared in global scope in each translation unit of a
3029 // program
3030 //
3031 // C++03:
3032 // void* operator new(std::size_t) throw(std::bad_alloc);
3033 // void* operator new[](std::size_t) throw(std::bad_alloc);
3034 // void operator delete(void*) throw();
3035 // void operator delete[](void*) throw();
3036 // C++11:
3037 // void* operator new(std::size_t);
3038 // void* operator new[](std::size_t);
3039 // void operator delete(void*) noexcept;
3040 // void operator delete[](void*) noexcept;
3041 // C++1y:
3042 // void* operator new(std::size_t);
3043 // void* operator new[](std::size_t);
3044 // void operator delete(void*) noexcept;
3045 // void operator delete[](void*) noexcept;
3046 // void operator delete(void*, std::size_t) noexcept;
3047 // void operator delete[](void*, std::size_t) noexcept;
3048 //
3049 // These implicit declarations introduce only the function names operator
3050 // new, operator new[], operator delete, operator delete[].
3051 //
3052 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
3053 // "std" or "bad_alloc" as necessary to form the exception specification.
3054 // However, we do not make these implicit declarations visible to name
3055 // lookup.
3056 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
3057 // The "std::bad_alloc" class has not yet been declared, so build it
3058 // implicitly.
3059 StdBadAlloc = CXXRecordDecl::Create(
3060 C: Context, TK: TagTypeKind::Class, DC: getOrCreateStdNamespace(),
3061 StartLoc: SourceLocation(), IdLoc: SourceLocation(),
3062 Id: &PP.getIdentifierTable().get(Name: "bad_alloc"), PrevDecl: nullptr);
3063 getStdBadAlloc()->setImplicit(true);
3064
3065 // The implicitly declared "std::bad_alloc" should live in global module
3066 // fragment.
3067 if (TheGlobalModuleFragment) {
3068 getStdBadAlloc()->setModuleOwnershipKind(
3069 Decl::ModuleOwnershipKind::ReachableWhenImported);
3070 getStdBadAlloc()->setLocalOwningModule(TheGlobalModuleFragment);
3071 }
3072 }
3073 if (!StdAlignValT && getLangOpts().AlignedAllocation) {
3074 // The "std::align_val_t" enum class has not yet been declared, so build it
3075 // implicitly.
3076 auto *AlignValT = EnumDecl::Create(
3077 C&: Context, DC: getOrCreateStdNamespace(), StartLoc: SourceLocation(), IdLoc: SourceLocation(),
3078 Id: &PP.getIdentifierTable().get(Name: "align_val_t"), PrevDecl: nullptr, IsScoped: true, IsScopedUsingClassTag: true, IsFixed: true);
3079
3080 // The implicitly declared "std::align_val_t" should live in global module
3081 // fragment.
3082 if (TheGlobalModuleFragment) {
3083 AlignValT->setModuleOwnershipKind(
3084 Decl::ModuleOwnershipKind::ReachableWhenImported);
3085 AlignValT->setLocalOwningModule(TheGlobalModuleFragment);
3086 }
3087
3088 AlignValT->setIntegerType(Context.getSizeType());
3089 AlignValT->setPromotionType(Context.getSizeType());
3090 AlignValT->setImplicit(true);
3091
3092 StdAlignValT = AlignValT;
3093 }
3094
3095 GlobalNewDeleteDeclared = true;
3096
3097 QualType VoidPtr = Context.getPointerType(T: Context.VoidTy);
3098 QualType SizeT = Context.getSizeType();
3099
3100 auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
3101 QualType Return, QualType Param) {
3102 llvm::SmallVector<QualType, 3> Params;
3103 Params.push_back(Elt: Param);
3104
3105 // Create up to four variants of the function (sized/aligned).
3106 bool HasSizedVariant = getLangOpts().SizedDeallocation &&
3107 (Kind == OO_Delete || Kind == OO_Array_Delete);
3108 bool HasAlignedVariant = getLangOpts().AlignedAllocation;
3109
3110 int NumSizeVariants = (HasSizedVariant ? 2 : 1);
3111 int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
3112 for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
3113 if (Sized)
3114 Params.push_back(Elt: SizeT);
3115
3116 for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
3117 if (Aligned)
3118 Params.push_back(Elt: Context.getTypeDeclType(Decl: getStdAlignValT()));
3119
3120 DeclareGlobalAllocationFunction(
3121 Name: Context.DeclarationNames.getCXXOperatorName(Op: Kind), Return, Params);
3122
3123 if (Aligned)
3124 Params.pop_back();
3125 }
3126 }
3127 };
3128
3129 DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
3130 DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
3131 DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
3132 DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
3133
3134 if (getLangOpts().CPlusPlusModules && getCurrentModule())
3135 PopGlobalModuleFragment();
3136}
3137
3138/// DeclareGlobalAllocationFunction - Declares a single implicit global
3139/// allocation function if it doesn't already exist.
3140void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
3141 QualType Return,
3142 ArrayRef<QualType> Params) {
3143 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
3144
3145 // Check if this function is already declared.
3146 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
3147 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
3148 Alloc != AllocEnd; ++Alloc) {
3149 // Only look at non-template functions, as it is the predefined,
3150 // non-templated allocation function we are trying to declare here.
3151 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Val: *Alloc)) {
3152 if (Func->getNumParams() == Params.size()) {
3153 llvm::SmallVector<QualType, 3> FuncParams;
3154 for (auto *P : Func->parameters())
3155 FuncParams.push_back(
3156 Elt: Context.getCanonicalType(T: P->getType().getUnqualifiedType()));
3157 if (llvm::ArrayRef(FuncParams) == Params) {
3158 // Make the function visible to name lookup, even if we found it in
3159 // an unimported module. It either is an implicitly-declared global
3160 // allocation function, or is suppressing that function.
3161 Func->setVisibleDespiteOwningModule();
3162 return;
3163 }
3164 }
3165 }
3166 }
3167
3168 FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
3169 /*IsVariadic=*/false, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
3170
3171 QualType BadAllocType;
3172 bool HasBadAllocExceptionSpec
3173 = (Name.getCXXOverloadedOperator() == OO_New ||
3174 Name.getCXXOverloadedOperator() == OO_Array_New);
3175 if (HasBadAllocExceptionSpec) {
3176 if (!getLangOpts().CPlusPlus11) {
3177 BadAllocType = Context.getTypeDeclType(Decl: getStdBadAlloc());
3178 assert(StdBadAlloc && "Must have std::bad_alloc declared");
3179 EPI.ExceptionSpec.Type = EST_Dynamic;
3180 EPI.ExceptionSpec.Exceptions = llvm::ArrayRef(BadAllocType);
3181 }
3182 if (getLangOpts().NewInfallible) {
3183 EPI.ExceptionSpec.Type = EST_DynamicNone;
3184 }
3185 } else {
3186 EPI.ExceptionSpec =
3187 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
3188 }
3189
3190 auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
3191 QualType FnType = Context.getFunctionType(ResultTy: Return, Args: Params, EPI);
3192 FunctionDecl *Alloc = FunctionDecl::Create(
3193 C&: Context, DC: GlobalCtx, StartLoc: SourceLocation(), NLoc: SourceLocation(), N: Name, T: FnType,
3194 /*TInfo=*/nullptr, SC: SC_None, UsesFPIntrin: getCurFPFeatures().isFPConstrained(), isInlineSpecified: false,
3195 hasWrittenPrototype: true);
3196 Alloc->setImplicit();
3197 // Global allocation functions should always be visible.
3198 Alloc->setVisibleDespiteOwningModule();
3199
3200 if (HasBadAllocExceptionSpec && getLangOpts().NewInfallible &&
3201 !getLangOpts().CheckNew)
3202 Alloc->addAttr(
3203 A: ReturnsNonNullAttr::CreateImplicit(Ctx&: Context, Range: Alloc->getLocation()));
3204
3205 // C++ [basic.stc.dynamic.general]p2:
3206 // The library provides default definitions for the global allocation
3207 // and deallocation functions. Some global allocation and deallocation
3208 // functions are replaceable ([new.delete]); these are attached to the
3209 // global module ([module.unit]).
3210 //
3211 // In the language wording, these functions are attched to the global
3212 // module all the time. But in the implementation, the global module
3213 // is only meaningful when we're in a module unit. So here we attach
3214 // these allocation functions to global module conditionally.
3215 if (TheGlobalModuleFragment) {
3216 Alloc->setModuleOwnershipKind(
3217 Decl::ModuleOwnershipKind::ReachableWhenImported);
3218 Alloc->setLocalOwningModule(TheGlobalModuleFragment);
3219 }
3220
3221 if (LangOpts.hasGlobalAllocationFunctionVisibility())
3222 Alloc->addAttr(A: VisibilityAttr::CreateImplicit(
3223 Ctx&: Context, Visibility: LangOpts.hasHiddenGlobalAllocationFunctionVisibility()
3224 ? VisibilityAttr::Hidden
3225 : LangOpts.hasProtectedGlobalAllocationFunctionVisibility()
3226 ? VisibilityAttr::Protected
3227 : VisibilityAttr::Default));
3228
3229 llvm::SmallVector<ParmVarDecl *, 3> ParamDecls;
3230 for (QualType T : Params) {
3231 ParamDecls.push_back(Elt: ParmVarDecl::Create(
3232 C&: Context, DC: Alloc, StartLoc: SourceLocation(), IdLoc: SourceLocation(), Id: nullptr, T,
3233 /*TInfo=*/nullptr, S: SC_None, DefArg: nullptr));
3234 ParamDecls.back()->setImplicit();
3235 }
3236 Alloc->setParams(ParamDecls);
3237 if (ExtraAttr)
3238 Alloc->addAttr(A: ExtraAttr);
3239 AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction(FD: Alloc);
3240 Context.getTranslationUnitDecl()->addDecl(D: Alloc);
3241 IdResolver.tryAddTopLevelDecl(D: Alloc, Name);
3242 };
3243
3244 if (!LangOpts.CUDA)
3245 CreateAllocationFunctionDecl(nullptr);
3246 else {
3247 // Host and device get their own declaration so each can be
3248 // defined or re-declared independently.
3249 CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Ctx&: Context));
3250 CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Ctx&: Context));
3251 }
3252}
3253
3254FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
3255 bool CanProvideSize,
3256 bool Overaligned,
3257 DeclarationName Name) {
3258 DeclareGlobalNewDelete();
3259
3260 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
3261 LookupQualifiedName(R&: FoundDelete, LookupCtx: Context.getTranslationUnitDecl());
3262
3263 // FIXME: It's possible for this to result in ambiguity, through a
3264 // user-declared variadic operator delete or the enable_if attribute. We
3265 // should probably not consider those cases to be usual deallocation
3266 // functions. But for now we just make an arbitrary choice in that case.
3267 auto Result = resolveDeallocationOverload(S&: *this, R&: FoundDelete, WantSize: CanProvideSize,
3268 WantAlign: Overaligned);
3269 assert(Result.FD && "operator delete missing from global scope?");
3270 return Result.FD;
3271}
3272
3273FunctionDecl *Sema::FindDeallocationFunctionForDestructor(SourceLocation Loc,
3274 CXXRecordDecl *RD) {
3275 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(Op: OO_Delete);
3276
3277 FunctionDecl *OperatorDelete = nullptr;
3278 if (FindDeallocationFunction(StartLoc: Loc, RD, Name, Operator&: OperatorDelete))
3279 return nullptr;
3280 if (OperatorDelete)
3281 return OperatorDelete;
3282
3283 // If there's no class-specific operator delete, look up the global
3284 // non-array delete.
3285 return FindUsualDeallocationFunction(
3286 StartLoc: Loc, CanProvideSize: true, Overaligned: hasNewExtendedAlignment(S&: *this, AllocType: Context.getRecordType(Decl: RD)),
3287 Name);
3288}
3289
3290bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
3291 DeclarationName Name,
3292 FunctionDecl *&Operator, bool Diagnose,
3293 bool WantSize, bool WantAligned) {
3294 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
3295 // Try to find operator delete/operator delete[] in class scope.
3296 LookupQualifiedName(R&: Found, LookupCtx: RD);
3297
3298 if (Found.isAmbiguous())
3299 return true;
3300
3301 Found.suppressDiagnostics();
3302
3303 bool Overaligned =
3304 WantAligned || hasNewExtendedAlignment(S&: *this, AllocType: Context.getRecordType(Decl: RD));
3305
3306 // C++17 [expr.delete]p10:
3307 // If the deallocation functions have class scope, the one without a
3308 // parameter of type std::size_t is selected.
3309 llvm::SmallVector<UsualDeallocFnInfo, 4> Matches;
3310 resolveDeallocationOverload(S&: *this, R&: Found, /*WantSize*/ WantSize,
3311 /*WantAlign*/ Overaligned, BestFns: &Matches);
3312
3313 // If we could find an overload, use it.
3314 if (Matches.size() == 1) {
3315 Operator = cast<CXXMethodDecl>(Val: Matches[0].FD);
3316
3317 // FIXME: DiagnoseUseOfDecl?
3318 if (Operator->isDeleted()) {
3319 if (Diagnose) {
3320 StringLiteral *Msg = Operator->getDeletedMessage();
3321 Diag(Loc: StartLoc, DiagID: diag::err_deleted_function_use)
3322 << (Msg != nullptr) << (Msg ? Msg->getString() : StringRef());
3323 NoteDeletedFunction(FD: Operator);
3324 }
3325 return true;
3326 }
3327
3328 if (CheckAllocationAccess(OperatorLoc: StartLoc, PlacementRange: SourceRange(), NamingClass: Found.getNamingClass(),
3329 FoundDecl: Matches[0].Found, Diagnose) == AR_inaccessible)
3330 return true;
3331
3332 return false;
3333 }
3334
3335 // We found multiple suitable operators; complain about the ambiguity.
3336 // FIXME: The standard doesn't say to do this; it appears that the intent
3337 // is that this should never happen.
3338 if (!Matches.empty()) {
3339 if (Diagnose) {
3340 Diag(Loc: StartLoc, DiagID: diag::err_ambiguous_suitable_delete_member_function_found)
3341 << Name << RD;
3342 for (auto &Match : Matches)
3343 Diag(Loc: Match.FD->getLocation(), DiagID: diag::note_member_declared_here) << Name;
3344 }
3345 return true;
3346 }
3347
3348 // We did find operator delete/operator delete[] declarations, but
3349 // none of them were suitable.
3350 if (!Found.empty()) {
3351 if (Diagnose) {
3352 Diag(Loc: StartLoc, DiagID: diag::err_no_suitable_delete_member_function_found)
3353 << Name << RD;
3354
3355 for (NamedDecl *D : Found)
3356 Diag(Loc: D->getUnderlyingDecl()->getLocation(),
3357 DiagID: diag::note_member_declared_here) << Name;
3358 }
3359 return true;
3360 }
3361
3362 Operator = nullptr;
3363 return false;
3364}
3365
3366namespace {
3367/// Checks whether delete-expression, and new-expression used for
3368/// initializing deletee have the same array form.
3369class MismatchingNewDeleteDetector {
3370public:
3371 enum MismatchResult {
3372 /// Indicates that there is no mismatch or a mismatch cannot be proven.
3373 NoMismatch,
3374 /// Indicates that variable is initialized with mismatching form of \a new.
3375 VarInitMismatches,
3376 /// Indicates that member is initialized with mismatching form of \a new.
3377 MemberInitMismatches,
3378 /// Indicates that 1 or more constructors' definitions could not been
3379 /// analyzed, and they will be checked again at the end of translation unit.
3380 AnalyzeLater
3381 };
3382
3383 /// \param EndOfTU True, if this is the final analysis at the end of
3384 /// translation unit. False, if this is the initial analysis at the point
3385 /// delete-expression was encountered.
3386 explicit MismatchingNewDeleteDetector(bool EndOfTU)
3387 : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
3388 HasUndefinedConstructors(false) {}
3389
3390 /// Checks whether pointee of a delete-expression is initialized with
3391 /// matching form of new-expression.
3392 ///
3393 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
3394 /// point where delete-expression is encountered, then a warning will be
3395 /// issued immediately. If return value is \c AnalyzeLater at the point where
3396 /// delete-expression is seen, then member will be analyzed at the end of
3397 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
3398 /// couldn't be analyzed. If at least one constructor initializes the member
3399 /// with matching type of new, the return value is \c NoMismatch.
3400 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
3401 /// Analyzes a class member.
3402 /// \param Field Class member to analyze.
3403 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
3404 /// for deleting the \p Field.
3405 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
3406 FieldDecl *Field;
3407 /// List of mismatching new-expressions used for initialization of the pointee
3408 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
3409 /// Indicates whether delete-expression was in array form.
3410 bool IsArrayForm;
3411
3412private:
3413 const bool EndOfTU;
3414 /// Indicates that there is at least one constructor without body.
3415 bool HasUndefinedConstructors;
3416 /// Returns \c CXXNewExpr from given initialization expression.
3417 /// \param E Expression used for initializing pointee in delete-expression.
3418 /// E can be a single-element \c InitListExpr consisting of new-expression.
3419 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
3420 /// Returns whether member is initialized with mismatching form of
3421 /// \c new either by the member initializer or in-class initialization.
3422 ///
3423 /// If bodies of all constructors are not visible at the end of translation
3424 /// unit or at least one constructor initializes member with the matching
3425 /// form of \c new, mismatch cannot be proven, and this function will return
3426 /// \c NoMismatch.
3427 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
3428 /// Returns whether variable is initialized with mismatching form of
3429 /// \c new.
3430 ///
3431 /// If variable is initialized with matching form of \c new or variable is not
3432 /// initialized with a \c new expression, this function will return true.
3433 /// If variable is initialized with mismatching form of \c new, returns false.
3434 /// \param D Variable to analyze.
3435 bool hasMatchingVarInit(const DeclRefExpr *D);
3436 /// Checks whether the constructor initializes pointee with mismatching
3437 /// form of \c new.
3438 ///
3439 /// Returns true, if member is initialized with matching form of \c new in
3440 /// member initializer list. Returns false, if member is initialized with the
3441 /// matching form of \c new in this constructor's initializer or given
3442 /// constructor isn't defined at the point where delete-expression is seen, or
3443 /// member isn't initialized by the constructor.
3444 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
3445 /// Checks whether member is initialized with matching form of
3446 /// \c new in member initializer list.
3447 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
3448 /// Checks whether member is initialized with mismatching form of \c new by
3449 /// in-class initializer.
3450 MismatchResult analyzeInClassInitializer();
3451};
3452}
3453
3454MismatchingNewDeleteDetector::MismatchResult
3455MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
3456 NewExprs.clear();
3457 assert(DE && "Expected delete-expression");
3458 IsArrayForm = DE->isArrayForm();
3459 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
3460 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(Val: E)) {
3461 return analyzeMemberExpr(ME);
3462 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(Val: E)) {
3463 if (!hasMatchingVarInit(D))
3464 return VarInitMismatches;
3465 }
3466 return NoMismatch;
3467}
3468
3469const CXXNewExpr *
3470MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
3471 assert(E != nullptr && "Expected a valid initializer expression");
3472 E = E->IgnoreParenImpCasts();
3473 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(Val: E)) {
3474 if (ILE->getNumInits() == 1)
3475 E = dyn_cast<const CXXNewExpr>(Val: ILE->getInit(Init: 0)->IgnoreParenImpCasts());
3476 }
3477
3478 return dyn_cast_or_null<const CXXNewExpr>(Val: E);
3479}
3480
3481bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
3482 const CXXCtorInitializer *CI) {
3483 const CXXNewExpr *NE = nullptr;
3484 if (Field == CI->getMember() &&
3485 (NE = getNewExprFromInitListOrExpr(E: CI->getInit()))) {
3486 if (NE->isArray() == IsArrayForm)
3487 return true;
3488 else
3489 NewExprs.push_back(Elt: NE);
3490 }
3491 return false;
3492}
3493
3494bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
3495 const CXXConstructorDecl *CD) {
3496 if (CD->isImplicit())
3497 return false;
3498 const FunctionDecl *Definition = CD;
3499 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
3500 HasUndefinedConstructors = true;
3501 return EndOfTU;
3502 }
3503 for (const auto *CI : cast<const CXXConstructorDecl>(Val: Definition)->inits()) {
3504 if (hasMatchingNewInCtorInit(CI))
3505 return true;
3506 }
3507 return false;
3508}
3509
3510MismatchingNewDeleteDetector::MismatchResult
3511MismatchingNewDeleteDetector::analyzeInClassInitializer() {
3512 assert(Field != nullptr && "This should be called only for members");
3513 const Expr *InitExpr = Field->getInClassInitializer();
3514 if (!InitExpr)
3515 return EndOfTU ? NoMismatch : AnalyzeLater;
3516 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(E: InitExpr)) {
3517 if (NE->isArray() != IsArrayForm) {
3518 NewExprs.push_back(Elt: NE);
3519 return MemberInitMismatches;
3520 }
3521 }
3522 return NoMismatch;
3523}
3524
3525MismatchingNewDeleteDetector::MismatchResult
3526MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
3527 bool DeleteWasArrayForm) {
3528 assert(Field != nullptr && "Analysis requires a valid class member.");
3529 this->Field = Field;
3530 IsArrayForm = DeleteWasArrayForm;
3531 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Val: Field->getParent());
3532 for (const auto *CD : RD->ctors()) {
3533 if (hasMatchingNewInCtor(CD))
3534 return NoMismatch;
3535 }
3536 if (HasUndefinedConstructors)
3537 return EndOfTU ? NoMismatch : AnalyzeLater;
3538 if (!NewExprs.empty())
3539 return MemberInitMismatches;
3540 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
3541 : NoMismatch;
3542}
3543
3544MismatchingNewDeleteDetector::MismatchResult
3545MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
3546 assert(ME != nullptr && "Expected a member expression");
3547 if (FieldDecl *F = dyn_cast<FieldDecl>(Val: ME->getMemberDecl()))
3548 return analyzeField(Field: F, DeleteWasArrayForm: IsArrayForm);
3549 return NoMismatch;
3550}
3551
3552bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
3553 const CXXNewExpr *NE = nullptr;
3554 if (const VarDecl *VD = dyn_cast<const VarDecl>(Val: D->getDecl())) {
3555 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(E: VD->getInit())) &&
3556 NE->isArray() != IsArrayForm) {
3557 NewExprs.push_back(Elt: NE);
3558 }
3559 }
3560 return NewExprs.empty();
3561}
3562
3563static void
3564DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
3565 const MismatchingNewDeleteDetector &Detector) {
3566 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(Loc: DeleteLoc);
3567 FixItHint H;
3568 if (!Detector.IsArrayForm)
3569 H = FixItHint::CreateInsertion(InsertionLoc: EndOfDelete, Code: "[]");
3570 else {
3571 SourceLocation RSquare = Lexer::findLocationAfterToken(
3572 loc: DeleteLoc, TKind: tok::l_square, SM: SemaRef.getSourceManager(),
3573 LangOpts: SemaRef.getLangOpts(), SkipTrailingWhitespaceAndNewLine: true);
3574 if (RSquare.isValid())
3575 H = FixItHint::CreateRemoval(RemoveRange: SourceRange(EndOfDelete, RSquare));
3576 }
3577 SemaRef.Diag(Loc: DeleteLoc, DiagID: diag::warn_mismatched_delete_new)
3578 << Detector.IsArrayForm << H;
3579
3580 for (const auto *NE : Detector.NewExprs)
3581 SemaRef.Diag(Loc: NE->getExprLoc(), DiagID: diag::note_allocated_here)
3582 << Detector.IsArrayForm;
3583}
3584
3585void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
3586 if (Diags.isIgnored(DiagID: diag::warn_mismatched_delete_new, Loc: SourceLocation()))
3587 return;
3588 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
3589 switch (Detector.analyzeDeleteExpr(DE)) {
3590 case MismatchingNewDeleteDetector::VarInitMismatches:
3591 case MismatchingNewDeleteDetector::MemberInitMismatches: {
3592 DiagnoseMismatchedNewDelete(SemaRef&: *this, DeleteLoc: DE->getBeginLoc(), Detector);
3593 break;
3594 }
3595 case MismatchingNewDeleteDetector::AnalyzeLater: {
3596 DeleteExprs[Detector.Field].push_back(
3597 Elt: std::make_pair(x: DE->getBeginLoc(), y: DE->isArrayForm()));
3598 break;
3599 }
3600 case MismatchingNewDeleteDetector::NoMismatch:
3601 break;
3602 }
3603}
3604
3605void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3606 bool DeleteWasArrayForm) {
3607 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3608 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3609 case MismatchingNewDeleteDetector::VarInitMismatches:
3610 llvm_unreachable("This analysis should have been done for class members.");
3611 case MismatchingNewDeleteDetector::AnalyzeLater:
3612 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
3613 "translation unit.");
3614 case MismatchingNewDeleteDetector::MemberInitMismatches:
3615 DiagnoseMismatchedNewDelete(SemaRef&: *this, DeleteLoc, Detector);
3616 break;
3617 case MismatchingNewDeleteDetector::NoMismatch:
3618 break;
3619 }
3620}
3621
3622ExprResult
3623Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3624 bool ArrayForm, Expr *ExE) {
3625 // C++ [expr.delete]p1:
3626 // The operand shall have a pointer type, or a class type having a single
3627 // non-explicit conversion function to a pointer type. The result has type
3628 // void.
3629 //
3630 // DR599 amends "pointer type" to "pointer to object type" in both cases.
3631
3632 ExprResult Ex = ExE;
3633 FunctionDecl *OperatorDelete = nullptr;
3634 bool ArrayFormAsWritten = ArrayForm;
3635 bool UsualArrayDeleteWantsSize = false;
3636
3637 if (!Ex.get()->isTypeDependent()) {
3638 // Perform lvalue-to-rvalue cast, if needed.
3639 Ex = DefaultLvalueConversion(E: Ex.get());
3640 if (Ex.isInvalid())
3641 return ExprError();
3642
3643 QualType Type = Ex.get()->getType();
3644
3645 class DeleteConverter : public ContextualImplicitConverter {
3646 public:
3647 DeleteConverter() : ContextualImplicitConverter(false, true) {}
3648
3649 bool match(QualType ConvType) override {
3650 // FIXME: If we have an operator T* and an operator void*, we must pick
3651 // the operator T*.
3652 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3653 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3654 return true;
3655 return false;
3656 }
3657
3658 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3659 QualType T) override {
3660 return S.Diag(Loc, DiagID: diag::err_delete_operand) << T;
3661 }
3662
3663 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3664 QualType T) override {
3665 return S.Diag(Loc, DiagID: diag::err_delete_incomplete_class_type) << T;
3666 }
3667
3668 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3669 QualType T,
3670 QualType ConvTy) override {
3671 return S.Diag(Loc, DiagID: diag::err_delete_explicit_conversion) << T << ConvTy;
3672 }
3673
3674 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3675 QualType ConvTy) override {
3676 return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_delete_conversion)
3677 << ConvTy;
3678 }
3679
3680 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3681 QualType T) override {
3682 return S.Diag(Loc, DiagID: diag::err_ambiguous_delete_operand) << T;
3683 }
3684
3685 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3686 QualType ConvTy) override {
3687 return S.Diag(Loc: Conv->getLocation(), DiagID: diag::note_delete_conversion)
3688 << ConvTy;
3689 }
3690
3691 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3692 QualType T,
3693 QualType ConvTy) override {
3694 llvm_unreachable("conversion functions are permitted");
3695 }
3696 } Converter;
3697
3698 Ex = PerformContextualImplicitConversion(Loc: StartLoc, FromE: Ex.get(), Converter);
3699 if (Ex.isInvalid())
3700 return ExprError();
3701 Type = Ex.get()->getType();
3702 if (!Converter.match(ConvType: Type))
3703 // FIXME: PerformContextualImplicitConversion should return ExprError
3704 // itself in this case.
3705 return ExprError();
3706
3707 QualType Pointee = Type->castAs<PointerType>()->getPointeeType();
3708 QualType PointeeElem = Context.getBaseElementType(QT: Pointee);
3709
3710 if (Pointee.getAddressSpace() != LangAS::Default &&
3711 !getLangOpts().OpenCLCPlusPlus)
3712 return Diag(Loc: Ex.get()->getBeginLoc(),
3713 DiagID: diag::err_address_space_qualified_delete)
3714 << Pointee.getUnqualifiedType()
3715 << Pointee.getQualifiers().getAddressSpaceAttributePrintValue();
3716
3717 CXXRecordDecl *PointeeRD = nullptr;
3718 if (Pointee->isVoidType() && !isSFINAEContext()) {
3719 // The C++ standard bans deleting a pointer to a non-object type, which
3720 // effectively bans deletion of "void*". However, most compilers support
3721 // this, so we treat it as a warning unless we're in a SFINAE context.
3722 // But we still prohibit this since C++26.
3723 Diag(Loc: StartLoc, DiagID: LangOpts.CPlusPlus26 ? diag::err_delete_incomplete
3724 : diag::ext_delete_void_ptr_operand)
3725 << (LangOpts.CPlusPlus26 ? Pointee : Type)
3726 << Ex.get()->getSourceRange();
3727 } else if (Pointee->isFunctionType() || Pointee->isVoidType() ||
3728 Pointee->isSizelessType()) {
3729 return ExprError(Diag(Loc: StartLoc, DiagID: diag::err_delete_operand)
3730 << Type << Ex.get()->getSourceRange());
3731 } else if (!Pointee->isDependentType()) {
3732 // FIXME: This can result in errors if the definition was imported from a
3733 // module but is hidden.
3734 if (!RequireCompleteType(Loc: StartLoc, T: Pointee,
3735 DiagID: LangOpts.CPlusPlus26
3736 ? diag::err_delete_incomplete
3737 : diag::warn_delete_incomplete,
3738 Args: Ex.get())) {
3739 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3740 PointeeRD = cast<CXXRecordDecl>(Val: RT->getDecl());
3741 }
3742 }
3743
3744 if (Pointee->isArrayType() && !ArrayForm) {
3745 Diag(Loc: StartLoc, DiagID: diag::warn_delete_array_type)
3746 << Type << Ex.get()->getSourceRange()
3747 << FixItHint::CreateInsertion(InsertionLoc: getLocForEndOfToken(Loc: StartLoc), Code: "[]");
3748 ArrayForm = true;
3749 }
3750
3751 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
3752 Op: ArrayForm ? OO_Array_Delete : OO_Delete);
3753
3754 if (PointeeRD) {
3755 if (!UseGlobal &&
3756 FindDeallocationFunction(StartLoc, RD: PointeeRD, Name: DeleteName,
3757 Operator&: OperatorDelete))
3758 return ExprError();
3759
3760 // If we're allocating an array of records, check whether the
3761 // usual operator delete[] has a size_t parameter.
3762 if (ArrayForm) {
3763 // If the user specifically asked to use the global allocator,
3764 // we'll need to do the lookup into the class.
3765 if (UseGlobal)
3766 UsualArrayDeleteWantsSize =
3767 doesUsualArrayDeleteWantSize(S&: *this, loc: StartLoc, allocType: PointeeElem);
3768
3769 // Otherwise, the usual operator delete[] should be the
3770 // function we just found.
3771 else if (isa_and_nonnull<CXXMethodDecl>(Val: OperatorDelete))
3772 UsualArrayDeleteWantsSize =
3773 UsualDeallocFnInfo(*this,
3774 DeclAccessPair::make(D: OperatorDelete, AS: AS_public))
3775 .HasSizeT;
3776 }
3777
3778 if (!PointeeRD->hasIrrelevantDestructor())
3779 if (CXXDestructorDecl *Dtor = LookupDestructor(Class: PointeeRD)) {
3780 MarkFunctionReferenced(Loc: StartLoc,
3781 Func: const_cast<CXXDestructorDecl*>(Dtor));
3782 if (DiagnoseUseOfDecl(D: Dtor, Locs: StartLoc))
3783 return ExprError();
3784 }
3785
3786 CheckVirtualDtorCall(dtor: PointeeRD->getDestructor(), Loc: StartLoc,
3787 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3788 /*WarnOnNonAbstractTypes=*/!ArrayForm,
3789 DtorLoc: SourceLocation());
3790 }
3791
3792 if (!OperatorDelete) {
3793 if (getLangOpts().OpenCLCPlusPlus) {
3794 Diag(Loc: StartLoc, DiagID: diag::err_openclcxx_not_supported) << "default delete";
3795 return ExprError();
3796 }
3797
3798 bool IsComplete = isCompleteType(Loc: StartLoc, T: Pointee);
3799 bool CanProvideSize =
3800 IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3801 Pointee.isDestructedType());
3802 bool Overaligned = hasNewExtendedAlignment(S&: *this, AllocType: Pointee);
3803
3804 // Look for a global declaration.
3805 OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3806 Overaligned, Name: DeleteName);
3807 }
3808
3809 MarkFunctionReferenced(Loc: StartLoc, Func: OperatorDelete);
3810
3811 // Check access and ambiguity of destructor if we're going to call it.
3812 // Note that this is required even for a virtual delete.
3813 bool IsVirtualDelete = false;
3814 if (PointeeRD) {
3815 if (CXXDestructorDecl *Dtor = LookupDestructor(Class: PointeeRD)) {
3816 CheckDestructorAccess(Loc: Ex.get()->getExprLoc(), Dtor,
3817 PDiag: PDiag(DiagID: diag::err_access_dtor) << PointeeElem);
3818 IsVirtualDelete = Dtor->isVirtual();
3819 }
3820 }
3821
3822 DiagnoseUseOfDecl(D: OperatorDelete, Locs: StartLoc);
3823
3824 // Convert the operand to the type of the first parameter of operator
3825 // delete. This is only necessary if we selected a destroying operator
3826 // delete that we are going to call (non-virtually); converting to void*
3827 // is trivial and left to AST consumers to handle.
3828 QualType ParamType = OperatorDelete->getParamDecl(i: 0)->getType();
3829 if (!IsVirtualDelete && !ParamType->getPointeeType()->isVoidType()) {
3830 Qualifiers Qs = Pointee.getQualifiers();
3831 if (Qs.hasCVRQualifiers()) {
3832 // Qualifiers are irrelevant to this conversion; we're only looking
3833 // for access and ambiguity.
3834 Qs.removeCVRQualifiers();
3835 QualType Unqual = Context.getPointerType(
3836 T: Context.getQualifiedType(T: Pointee.getUnqualifiedType(), Qs));
3837 Ex = ImpCastExprToType(E: Ex.get(), Type: Unqual, CK: CK_NoOp);
3838 }
3839 Ex = PerformImplicitConversion(From: Ex.get(), ToType: ParamType, Action: AA_Passing);
3840 if (Ex.isInvalid())
3841 return ExprError();
3842 }
3843 }
3844
3845 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3846 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3847 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3848 AnalyzeDeleteExprMismatch(DE: Result);
3849 return Result;
3850}
3851
3852static bool resolveBuiltinNewDeleteOverload(Sema &S, CallExpr *TheCall,
3853 bool IsDelete,
3854 FunctionDecl *&Operator) {
3855
3856 DeclarationName NewName = S.Context.DeclarationNames.getCXXOperatorName(
3857 Op: IsDelete ? OO_Delete : OO_New);
3858
3859 LookupResult R(S, NewName, TheCall->getBeginLoc(), Sema::LookupOrdinaryName);
3860 S.LookupQualifiedName(R, LookupCtx: S.Context.getTranslationUnitDecl());
3861 assert(!R.empty() && "implicitly declared allocation functions not found");
3862 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
3863
3864 // We do our own custom access checks below.
3865 R.suppressDiagnostics();
3866
3867 SmallVector<Expr *, 8> Args(TheCall->arguments());
3868 OverloadCandidateSet Candidates(R.getNameLoc(),
3869 OverloadCandidateSet::CSK_Normal);
3870 for (LookupResult::iterator FnOvl = R.begin(), FnOvlEnd = R.end();
3871 FnOvl != FnOvlEnd; ++FnOvl) {
3872 // Even member operator new/delete are implicitly treated as
3873 // static, so don't use AddMemberCandidate.
3874 NamedDecl *D = (*FnOvl)->getUnderlyingDecl();
3875
3876 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(Val: D)) {
3877 S.AddTemplateOverloadCandidate(FunctionTemplate: FnTemplate, FoundDecl: FnOvl.getPair(),
3878 /*ExplicitTemplateArgs=*/nullptr, Args,
3879 CandidateSet&: Candidates,
3880 /*SuppressUserConversions=*/false);
3881 continue;
3882 }
3883
3884 FunctionDecl *Fn = cast<FunctionDecl>(Val: D);
3885 S.AddOverloadCandidate(Function: Fn, FoundDecl: FnOvl.getPair(), Args, CandidateSet&: Candidates,
3886 /*SuppressUserConversions=*/false);
3887 }
3888
3889 SourceRange Range = TheCall->getSourceRange();
3890
3891 // Do the resolution.
3892 OverloadCandidateSet::iterator Best;
3893 switch (Candidates.BestViableFunction(S, Loc: R.getNameLoc(), Best)) {
3894 case OR_Success: {
3895 // Got one!
3896 FunctionDecl *FnDecl = Best->Function;
3897 assert(R.getNamingClass() == nullptr &&
3898 "class members should not be considered");
3899
3900 if (!FnDecl->isReplaceableGlobalAllocationFunction()) {
3901 S.Diag(Loc: R.getNameLoc(), DiagID: diag::err_builtin_operator_new_delete_not_usual)
3902 << (IsDelete ? 1 : 0) << Range;
3903 S.Diag(Loc: FnDecl->getLocation(), DiagID: diag::note_non_usual_function_declared_here)
3904 << R.getLookupName() << FnDecl->getSourceRange();
3905 return true;
3906 }
3907
3908 Operator = FnDecl;
3909 return false;
3910 }
3911
3912 case OR_No_Viable_Function:
3913 Candidates.NoteCandidates(
3914 PA: PartialDiagnosticAt(R.getNameLoc(),
3915 S.PDiag(DiagID: diag::err_ovl_no_viable_function_in_call)
3916 << R.getLookupName() << Range),
3917 S, OCD: OCD_AllCandidates, Args);
3918 return true;
3919
3920 case OR_Ambiguous:
3921 Candidates.NoteCandidates(
3922 PA: PartialDiagnosticAt(R.getNameLoc(),
3923 S.PDiag(DiagID: diag::err_ovl_ambiguous_call)
3924 << R.getLookupName() << Range),
3925 S, OCD: OCD_AmbiguousCandidates, Args);
3926 return true;
3927
3928 case OR_Deleted:
3929 S.DiagnoseUseOfDeletedFunction(Loc: R.getNameLoc(), Range, Name: R.getLookupName(),
3930 CandidateSet&: Candidates, Fn: Best->Function, Args);
3931 return true;
3932 }
3933 llvm_unreachable("Unreachable, bad result from BestViableFunction");
3934}
3935
3936ExprResult Sema::BuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
3937 bool IsDelete) {
3938 CallExpr *TheCall = cast<CallExpr>(Val: TheCallResult.get());
3939 if (!getLangOpts().CPlusPlus) {
3940 Diag(Loc: TheCall->getExprLoc(), DiagID: diag::err_builtin_requires_language)
3941 << (IsDelete ? "__builtin_operator_delete" : "__builtin_operator_new")
3942 << "C++";
3943 return ExprError();
3944 }
3945 // CodeGen assumes it can find the global new and delete to call,
3946 // so ensure that they are declared.
3947 DeclareGlobalNewDelete();
3948
3949 FunctionDecl *OperatorNewOrDelete = nullptr;
3950 if (resolveBuiltinNewDeleteOverload(S&: *this, TheCall, IsDelete,
3951 Operator&: OperatorNewOrDelete))
3952 return ExprError();
3953 assert(OperatorNewOrDelete && "should be found");
3954
3955 DiagnoseUseOfDecl(D: OperatorNewOrDelete, Locs: TheCall->getExprLoc());
3956 MarkFunctionReferenced(Loc: TheCall->getExprLoc(), Func: OperatorNewOrDelete);
3957
3958 TheCall->setType(OperatorNewOrDelete->getReturnType());
3959 for (unsigned i = 0; i != TheCall->getNumArgs(); ++i) {
3960 QualType ParamTy = OperatorNewOrDelete->getParamDecl(i)->getType();
3961 InitializedEntity Entity =
3962 InitializedEntity::InitializeParameter(Context, Type: ParamTy, Consumed: false);
3963 ExprResult Arg = PerformCopyInitialization(
3964 Entity, EqualLoc: TheCall->getArg(Arg: i)->getBeginLoc(), Init: TheCall->getArg(Arg: i));
3965 if (Arg.isInvalid())
3966 return ExprError();
3967 TheCall->setArg(Arg: i, ArgExpr: Arg.get());
3968 }
3969 auto Callee = dyn_cast<ImplicitCastExpr>(Val: TheCall->getCallee());
3970 assert(Callee && Callee->getCastKind() == CK_BuiltinFnToFnPtr &&
3971 "Callee expected to be implicit cast to a builtin function pointer");
3972 Callee->setType(OperatorNewOrDelete->getType());
3973
3974 return TheCallResult;
3975}
3976
3977void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3978 bool IsDelete, bool CallCanBeVirtual,
3979 bool WarnOnNonAbstractTypes,
3980 SourceLocation DtorLoc) {
3981 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual || isUnevaluatedContext())
3982 return;
3983
3984 // C++ [expr.delete]p3:
3985 // In the first alternative (delete object), if the static type of the
3986 // object to be deleted is different from its dynamic type, the static
3987 // type shall be a base class of the dynamic type of the object to be
3988 // deleted and the static type shall have a virtual destructor or the
3989 // behavior is undefined.
3990 //
3991 const CXXRecordDecl *PointeeRD = dtor->getParent();
3992 // Note: a final class cannot be derived from, no issue there
3993 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3994 return;
3995
3996 // If the superclass is in a system header, there's nothing that can be done.
3997 // The `delete` (where we emit the warning) can be in a system header,
3998 // what matters for this warning is where the deleted type is defined.
3999 if (getSourceManager().isInSystemHeader(Loc: PointeeRD->getLocation()))
4000 return;
4001
4002 QualType ClassType = dtor->getFunctionObjectParameterType();
4003 if (PointeeRD->isAbstract()) {
4004 // If the class is abstract, we warn by default, because we're
4005 // sure the code has undefined behavior.
4006 Diag(Loc, DiagID: diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
4007 << ClassType;
4008 } else if (WarnOnNonAbstractTypes) {
4009 // Otherwise, if this is not an array delete, it's a bit suspect,
4010 // but not necessarily wrong.
4011 Diag(Loc, DiagID: diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
4012 << ClassType;
4013 }
4014 if (!IsDelete) {
4015 std::string TypeStr;
4016 ClassType.getAsStringInternal(Str&: TypeStr, Policy: getPrintingPolicy());
4017 Diag(Loc: DtorLoc, DiagID: diag::note_delete_non_virtual)
4018 << FixItHint::CreateInsertion(InsertionLoc: DtorLoc, Code: TypeStr + "::");
4019 }
4020}
4021
4022Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
4023 SourceLocation StmtLoc,
4024 ConditionKind CK) {
4025 ExprResult E =
4026 CheckConditionVariable(ConditionVar: cast<VarDecl>(Val: ConditionVar), StmtLoc, CK);
4027 if (E.isInvalid())
4028 return ConditionError();
4029 return ConditionResult(*this, ConditionVar, MakeFullExpr(Arg: E.get(), CC: StmtLoc),
4030 CK == ConditionKind::ConstexprIf);
4031}
4032
4033ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
4034 SourceLocation StmtLoc,
4035 ConditionKind CK) {
4036 if (ConditionVar->isInvalidDecl())
4037 return ExprError();
4038
4039 QualType T = ConditionVar->getType();
4040
4041 // C++ [stmt.select]p2:
4042 // The declarator shall not specify a function or an array.
4043 if (T->isFunctionType())
4044 return ExprError(Diag(Loc: ConditionVar->getLocation(),
4045 DiagID: diag::err_invalid_use_of_function_type)
4046 << ConditionVar->getSourceRange());
4047 else if (T->isArrayType())
4048 return ExprError(Diag(Loc: ConditionVar->getLocation(),
4049 DiagID: diag::err_invalid_use_of_array_type)
4050 << ConditionVar->getSourceRange());
4051
4052 ExprResult Condition = BuildDeclRefExpr(
4053 D: ConditionVar, Ty: ConditionVar->getType().getNonReferenceType(), VK: VK_LValue,
4054 Loc: ConditionVar->getLocation());
4055
4056 switch (CK) {
4057 case ConditionKind::Boolean:
4058 return CheckBooleanCondition(Loc: StmtLoc, E: Condition.get());
4059
4060 case ConditionKind::ConstexprIf:
4061 return CheckBooleanCondition(Loc: StmtLoc, E: Condition.get(), IsConstexpr: true);
4062
4063 case ConditionKind::Switch:
4064 return CheckSwitchCondition(SwitchLoc: StmtLoc, Cond: Condition.get());
4065 }
4066
4067 llvm_unreachable("unexpected condition kind");
4068}
4069
4070ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
4071 // C++11 6.4p4:
4072 // The value of a condition that is an initialized declaration in a statement
4073 // other than a switch statement is the value of the declared variable
4074 // implicitly converted to type bool. If that conversion is ill-formed, the
4075 // program is ill-formed.
4076 // The value of a condition that is an expression is the value of the
4077 // expression, implicitly converted to bool.
4078 //
4079 // C++23 8.5.2p2
4080 // If the if statement is of the form if constexpr, the value of the condition
4081 // is contextually converted to bool and the converted expression shall be
4082 // a constant expression.
4083 //
4084
4085 ExprResult E = PerformContextuallyConvertToBool(From: CondExpr);
4086 if (!IsConstexpr || E.isInvalid() || E.get()->isValueDependent())
4087 return E;
4088
4089 // FIXME: Return this value to the caller so they don't need to recompute it.
4090 llvm::APSInt Cond;
4091 E = VerifyIntegerConstantExpression(
4092 E: E.get(), Result: &Cond,
4093 DiagID: diag::err_constexpr_if_condition_expression_is_not_constant);
4094 return E;
4095}
4096
4097bool
4098Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
4099 // Look inside the implicit cast, if it exists.
4100 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(Val: From))
4101 From = Cast->getSubExpr();
4102
4103 // A string literal (2.13.4) that is not a wide string literal can
4104 // be converted to an rvalue of type "pointer to char"; a wide
4105 // string literal can be converted to an rvalue of type "pointer
4106 // to wchar_t" (C++ 4.2p2).
4107 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(Val: From->IgnoreParens()))
4108 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
4109 if (const BuiltinType *ToPointeeType
4110 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
4111 // This conversion is considered only when there is an
4112 // explicit appropriate pointer target type (C++ 4.2p2).
4113 if (!ToPtrType->getPointeeType().hasQualifiers()) {
4114 switch (StrLit->getKind()) {
4115 case StringLiteralKind::UTF8:
4116 case StringLiteralKind::UTF16:
4117 case StringLiteralKind::UTF32:
4118 // We don't allow UTF literals to be implicitly converted
4119 break;
4120 case StringLiteralKind::Ordinary:
4121 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
4122 ToPointeeType->getKind() == BuiltinType::Char_S);
4123 case StringLiteralKind::Wide:
4124 return Context.typesAreCompatible(T1: Context.getWideCharType(),
4125 T2: QualType(ToPointeeType, 0));
4126 case StringLiteralKind::Unevaluated:
4127 assert(false && "Unevaluated string literal in expression");
4128 break;
4129 }
4130 }
4131 }
4132
4133 return false;
4134}
4135
4136static ExprResult BuildCXXCastArgument(Sema &S,
4137 SourceLocation CastLoc,
4138 QualType Ty,
4139 CastKind Kind,
4140 CXXMethodDecl *Method,
4141 DeclAccessPair FoundDecl,
4142 bool HadMultipleCandidates,
4143 Expr *From) {
4144 switch (Kind) {
4145 default: llvm_unreachable("Unhandled cast kind!");
4146 case CK_ConstructorConversion: {
4147 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Val: Method);
4148 SmallVector<Expr*, 8> ConstructorArgs;
4149
4150 if (S.RequireNonAbstractType(Loc: CastLoc, T: Ty,
4151 DiagID: diag::err_allocation_of_abstract_type))
4152 return ExprError();
4153
4154 if (S.CompleteConstructorCall(Constructor, DeclInitType: Ty, ArgsPtr: From, Loc: CastLoc,
4155 ConvertedArgs&: ConstructorArgs))
4156 return ExprError();
4157
4158 S.CheckConstructorAccess(Loc: CastLoc, D: Constructor, FoundDecl,
4159 Entity: InitializedEntity::InitializeTemporary(Type: Ty));
4160 if (S.DiagnoseUseOfDecl(D: Method, Locs: CastLoc))
4161 return ExprError();
4162
4163 ExprResult Result = S.BuildCXXConstructExpr(
4164 ConstructLoc: CastLoc, DeclInitType: Ty, FoundDecl, Constructor: cast<CXXConstructorDecl>(Val: Method),
4165 Exprs: ConstructorArgs, HadMultipleCandidates,
4166 /*ListInit*/ IsListInitialization: false, /*StdInitListInit*/ IsStdInitListInitialization: false, /*ZeroInit*/ RequiresZeroInit: false,
4167 ConstructKind: CXXConstructionKind::Complete, ParenRange: SourceRange());
4168 if (Result.isInvalid())
4169 return ExprError();
4170
4171 return S.MaybeBindToTemporary(E: Result.getAs<Expr>());
4172 }
4173
4174 case CK_UserDefinedConversion: {
4175 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
4176
4177 S.CheckMemberOperatorAccess(Loc: CastLoc, ObjectExpr: From, /*arg*/ ArgExpr: nullptr, FoundDecl);
4178 if (S.DiagnoseUseOfDecl(D: Method, Locs: CastLoc))
4179 return ExprError();
4180
4181 // Create an implicit call expr that calls it.
4182 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Val: Method);
4183 ExprResult Result = S.BuildCXXMemberCallExpr(Exp: From, FoundDecl, Method: Conv,
4184 HadMultipleCandidates);
4185 if (Result.isInvalid())
4186 return ExprError();
4187 // Record usage of conversion in an implicit cast.
4188 Result = ImplicitCastExpr::Create(Context: S.Context, T: Result.get()->getType(),
4189 Kind: CK_UserDefinedConversion, Operand: Result.get(),
4190 BasePath: nullptr, Cat: Result.get()->getValueKind(),
4191 FPO: S.CurFPFeatureOverrides());
4192
4193 return S.MaybeBindToTemporary(E: Result.get());
4194 }
4195 }
4196}
4197
4198ExprResult
4199Sema::PerformImplicitConversion(Expr *From, QualType ToType,
4200 const ImplicitConversionSequence &ICS,
4201 AssignmentAction Action,
4202 CheckedConversionKind CCK) {
4203 // C++ [over.match.oper]p7: [...] operands of class type are converted [...]
4204 if (CCK == CheckedConversionKind::ForBuiltinOverloadedOp &&
4205 !From->getType()->isRecordType())
4206 return From;
4207
4208 switch (ICS.getKind()) {
4209 case ImplicitConversionSequence::StandardConversion: {
4210 ExprResult Res = PerformImplicitConversion(From, ToType, SCS: ICS.Standard,
4211 Action, CCK);
4212 if (Res.isInvalid())
4213 return ExprError();
4214 From = Res.get();
4215 break;
4216 }
4217
4218 case ImplicitConversionSequence::UserDefinedConversion: {
4219
4220 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
4221 CastKind CastKind;
4222 QualType BeforeToType;
4223 assert(FD && "no conversion function for user-defined conversion seq");
4224 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(Val: FD)) {
4225 CastKind = CK_UserDefinedConversion;
4226
4227 // If the user-defined conversion is specified by a conversion function,
4228 // the initial standard conversion sequence converts the source type to
4229 // the implicit object parameter of the conversion function.
4230 BeforeToType = Context.getTagDeclType(Decl: Conv->getParent());
4231 } else {
4232 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(Val: FD);
4233 CastKind = CK_ConstructorConversion;
4234 // Do no conversion if dealing with ... for the first conversion.
4235 if (!ICS.UserDefined.EllipsisConversion) {
4236 // If the user-defined conversion is specified by a constructor, the
4237 // initial standard conversion sequence converts the source type to
4238 // the type required by the argument of the constructor
4239 BeforeToType = Ctor->getParamDecl(i: 0)->getType().getNonReferenceType();
4240 }
4241 }
4242 // Watch out for ellipsis conversion.
4243 if (!ICS.UserDefined.EllipsisConversion) {
4244 ExprResult Res =
4245 PerformImplicitConversion(From, ToType: BeforeToType,
4246 SCS: ICS.UserDefined.Before, Action: AA_Converting,
4247 CCK);
4248 if (Res.isInvalid())
4249 return ExprError();
4250 From = Res.get();
4251 }
4252
4253 ExprResult CastArg = BuildCXXCastArgument(
4254 S&: *this, CastLoc: From->getBeginLoc(), Ty: ToType.getNonReferenceType(), Kind: CastKind,
4255 Method: cast<CXXMethodDecl>(Val: FD), FoundDecl: ICS.UserDefined.FoundConversionFunction,
4256 HadMultipleCandidates: ICS.UserDefined.HadMultipleCandidates, From);
4257
4258 if (CastArg.isInvalid())
4259 return ExprError();
4260
4261 From = CastArg.get();
4262
4263 // C++ [over.match.oper]p7:
4264 // [...] the second standard conversion sequence of a user-defined
4265 // conversion sequence is not applied.
4266 if (CCK == CheckedConversionKind::ForBuiltinOverloadedOp)
4267 return From;
4268
4269 return PerformImplicitConversion(From, ToType, SCS: ICS.UserDefined.After,
4270 Action: AA_Converting, CCK);
4271 }
4272
4273 case ImplicitConversionSequence::AmbiguousConversion:
4274 ICS.DiagnoseAmbiguousConversion(S&: *this, CaretLoc: From->getExprLoc(),
4275 PDiag: PDiag(DiagID: diag::err_typecheck_ambiguous_condition)
4276 << From->getSourceRange());
4277 return ExprError();
4278
4279 case ImplicitConversionSequence::EllipsisConversion:
4280 case ImplicitConversionSequence::StaticObjectArgumentConversion:
4281 llvm_unreachable("bad conversion");
4282
4283 case ImplicitConversionSequence::BadConversion:
4284 Sema::AssignConvertType ConvTy =
4285 CheckAssignmentConstraints(Loc: From->getExprLoc(), LHSType: ToType, RHSType: From->getType());
4286 bool Diagnosed = DiagnoseAssignmentResult(
4287 ConvTy: ConvTy == Compatible ? Incompatible : ConvTy, Loc: From->getExprLoc(),
4288 DstType: ToType, SrcType: From->getType(), SrcExpr: From, Action);
4289 assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
4290 return ExprError();
4291 }
4292
4293 // Everything went well.
4294 return From;
4295}
4296
4297// adjustVectorType - Compute the intermediate cast type casting elements of the
4298// from type to the elements of the to type without resizing the vector.
4299static QualType adjustVectorType(ASTContext &Context, QualType FromTy,
4300 QualType ToType, QualType *ElTy = nullptr) {
4301 auto *ToVec = ToType->castAs<VectorType>();
4302 QualType ElType = ToVec->getElementType();
4303 if (ElTy)
4304 *ElTy = ElType;
4305 if (!FromTy->isVectorType())
4306 return ElType;
4307 auto *FromVec = FromTy->castAs<VectorType>();
4308 return Context.getExtVectorType(VectorType: ElType, NumElts: FromVec->getNumElements());
4309}
4310
4311ExprResult
4312Sema::PerformImplicitConversion(Expr *From, QualType ToType,
4313 const StandardConversionSequence& SCS,
4314 AssignmentAction Action,
4315 CheckedConversionKind CCK) {
4316 bool CStyle = (CCK == CheckedConversionKind::CStyleCast ||
4317 CCK == CheckedConversionKind::FunctionalCast);
4318
4319 // Overall FIXME: we are recomputing too many types here and doing far too
4320 // much extra work. What this means is that we need to keep track of more
4321 // information that is computed when we try the implicit conversion initially,
4322 // so that we don't need to recompute anything here.
4323 QualType FromType = From->getType();
4324
4325 if (SCS.CopyConstructor) {
4326 // FIXME: When can ToType be a reference type?
4327 assert(!ToType->isReferenceType());
4328 if (SCS.Second == ICK_Derived_To_Base) {
4329 SmallVector<Expr*, 8> ConstructorArgs;
4330 if (CompleteConstructorCall(
4331 Constructor: cast<CXXConstructorDecl>(Val: SCS.CopyConstructor), DeclInitType: ToType, ArgsPtr: From,
4332 /*FIXME:ConstructLoc*/ Loc: SourceLocation(), ConvertedArgs&: ConstructorArgs))
4333 return ExprError();
4334 return BuildCXXConstructExpr(
4335 /*FIXME:ConstructLoc*/ ConstructLoc: SourceLocation(), DeclInitType: ToType,
4336 FoundDecl: SCS.FoundCopyConstructor, Constructor: SCS.CopyConstructor, Exprs: ConstructorArgs,
4337 /*HadMultipleCandidates*/ false,
4338 /*ListInit*/ IsListInitialization: false, /*StdInitListInit*/ IsStdInitListInitialization: false, /*ZeroInit*/ RequiresZeroInit: false,
4339 ConstructKind: CXXConstructionKind::Complete, ParenRange: SourceRange());
4340 }
4341 return BuildCXXConstructExpr(
4342 /*FIXME:ConstructLoc*/ ConstructLoc: SourceLocation(), DeclInitType: ToType,
4343 FoundDecl: SCS.FoundCopyConstructor, Constructor: SCS.CopyConstructor, Exprs: From,
4344 /*HadMultipleCandidates*/ false,
4345 /*ListInit*/ IsListInitialization: false, /*StdInitListInit*/ IsStdInitListInitialization: false, /*ZeroInit*/ RequiresZeroInit: false,
4346 ConstructKind: CXXConstructionKind::Complete, ParenRange: SourceRange());
4347 }
4348
4349 // Resolve overloaded function references.
4350 if (Context.hasSameType(T1: FromType, T2: Context.OverloadTy)) {
4351 DeclAccessPair Found;
4352 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(AddressOfExpr: From, TargetType: ToType,
4353 Complain: true, Found);
4354 if (!Fn)
4355 return ExprError();
4356
4357 if (DiagnoseUseOfDecl(D: Fn, Locs: From->getBeginLoc()))
4358 return ExprError();
4359
4360 ExprResult Res = FixOverloadedFunctionReference(E: From, FoundDecl: Found, Fn);
4361 if (Res.isInvalid())
4362 return ExprError();
4363
4364 // We might get back another placeholder expression if we resolved to a
4365 // builtin.
4366 Res = CheckPlaceholderExpr(E: Res.get());
4367 if (Res.isInvalid())
4368 return ExprError();
4369
4370 From = Res.get();
4371 FromType = From->getType();
4372 }
4373
4374 // If we're converting to an atomic type, first convert to the corresponding
4375 // non-atomic type.
4376 QualType ToAtomicType;
4377 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
4378 ToAtomicType = ToType;
4379 ToType = ToAtomic->getValueType();
4380 }
4381
4382 QualType InitialFromType = FromType;
4383 // Perform the first implicit conversion.
4384 switch (SCS.First) {
4385 case ICK_Identity:
4386 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
4387 FromType = FromAtomic->getValueType().getUnqualifiedType();
4388 From = ImplicitCastExpr::Create(Context, T: FromType, Kind: CK_AtomicToNonAtomic,
4389 Operand: From, /*BasePath=*/nullptr, Cat: VK_PRValue,
4390 FPO: FPOptionsOverride());
4391 }
4392 break;
4393
4394 case ICK_Lvalue_To_Rvalue: {
4395 assert(From->getObjectKind() != OK_ObjCProperty);
4396 ExprResult FromRes = DefaultLvalueConversion(E: From);
4397 if (FromRes.isInvalid())
4398 return ExprError();
4399
4400 From = FromRes.get();
4401 FromType = From->getType();
4402 break;
4403 }
4404
4405 case ICK_Array_To_Pointer:
4406 FromType = Context.getArrayDecayedType(T: FromType);
4407 From = ImpCastExprToType(E: From, Type: FromType, CK: CK_ArrayToPointerDecay, VK: VK_PRValue,
4408 /*BasePath=*/nullptr, CCK)
4409 .get();
4410 break;
4411
4412 case ICK_HLSL_Array_RValue:
4413 FromType = Context.getArrayParameterType(Ty: FromType);
4414 From = ImpCastExprToType(E: From, Type: FromType, CK: CK_HLSLArrayRValue, VK: VK_PRValue,
4415 /*BasePath=*/nullptr, CCK)
4416 .get();
4417 break;
4418
4419 case ICK_Function_To_Pointer:
4420 FromType = Context.getPointerType(T: FromType);
4421 From = ImpCastExprToType(E: From, Type: FromType, CK: CK_FunctionToPointerDecay,
4422 VK: VK_PRValue, /*BasePath=*/nullptr, CCK)
4423 .get();
4424 break;
4425
4426 default:
4427 llvm_unreachable("Improper first standard conversion");
4428 }
4429
4430 // Perform the second implicit conversion
4431 switch (SCS.Second) {
4432 case ICK_Identity:
4433 // C++ [except.spec]p5:
4434 // [For] assignment to and initialization of pointers to functions,
4435 // pointers to member functions, and references to functions: the
4436 // target entity shall allow at least the exceptions allowed by the
4437 // source value in the assignment or initialization.
4438 switch (Action) {
4439 case AA_Assigning:
4440 case AA_Initializing:
4441 // Note, function argument passing and returning are initialization.
4442 case AA_Passing:
4443 case AA_Returning:
4444 case AA_Sending:
4445 case AA_Passing_CFAudited:
4446 if (CheckExceptionSpecCompatibility(From, ToType))
4447 return ExprError();
4448 break;
4449
4450 case AA_Casting:
4451 case AA_Converting:
4452 // Casts and implicit conversions are not initialization, so are not
4453 // checked for exception specification mismatches.
4454 break;
4455 }
4456 // Nothing else to do.
4457 break;
4458
4459 case ICK_Integral_Promotion:
4460 case ICK_Integral_Conversion: {
4461 QualType ElTy = ToType;
4462 QualType StepTy = ToType;
4463 if (ToType->isVectorType())
4464 StepTy = adjustVectorType(Context, FromTy: FromType, ToType, ElTy: &ElTy);
4465 if (ElTy->isBooleanType()) {
4466 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
4467 SCS.Second == ICK_Integral_Promotion &&
4468 "only enums with fixed underlying type can promote to bool");
4469 From = ImpCastExprToType(E: From, Type: StepTy, CK: CK_IntegralToBoolean, VK: VK_PRValue,
4470 /*BasePath=*/nullptr, CCK)
4471 .get();
4472 } else {
4473 From = ImpCastExprToType(E: From, Type: StepTy, CK: CK_IntegralCast, VK: VK_PRValue,
4474 /*BasePath=*/nullptr, CCK)
4475 .get();
4476 }
4477 break;
4478 }
4479
4480 case ICK_Floating_Promotion:
4481 case ICK_Floating_Conversion: {
4482 QualType StepTy = ToType;
4483 if (ToType->isVectorType())
4484 StepTy = adjustVectorType(Context, FromTy: FromType, ToType);
4485 From = ImpCastExprToType(E: From, Type: StepTy, CK: CK_FloatingCast, VK: VK_PRValue,
4486 /*BasePath=*/nullptr, CCK)
4487 .get();
4488 break;
4489 }
4490
4491 case ICK_Complex_Promotion:
4492 case ICK_Complex_Conversion: {
4493 QualType FromEl = From->getType()->castAs<ComplexType>()->getElementType();
4494 QualType ToEl = ToType->castAs<ComplexType>()->getElementType();
4495 CastKind CK;
4496 if (FromEl->isRealFloatingType()) {
4497 if (ToEl->isRealFloatingType())
4498 CK = CK_FloatingComplexCast;
4499 else
4500 CK = CK_FloatingComplexToIntegralComplex;
4501 } else if (ToEl->isRealFloatingType()) {
4502 CK = CK_IntegralComplexToFloatingComplex;
4503 } else {
4504 CK = CK_IntegralComplexCast;
4505 }
4506 From = ImpCastExprToType(E: From, Type: ToType, CK, VK: VK_PRValue, /*BasePath=*/nullptr,
4507 CCK)
4508 .get();
4509 break;
4510 }
4511
4512 case ICK_Floating_Integral: {
4513 QualType ElTy = ToType;
4514 QualType StepTy = ToType;
4515 if (ToType->isVectorType())
4516 StepTy = adjustVectorType(Context, FromTy: FromType, ToType, ElTy: &ElTy);
4517 if (ElTy->isRealFloatingType())
4518 From = ImpCastExprToType(E: From, Type: StepTy, CK: CK_IntegralToFloating, VK: VK_PRValue,
4519 /*BasePath=*/nullptr, CCK)
4520 .get();
4521 else
4522 From = ImpCastExprToType(E: From, Type: StepTy, CK: CK_FloatingToIntegral, VK: VK_PRValue,
4523 /*BasePath=*/nullptr, CCK)
4524 .get();
4525 break;
4526 }
4527
4528 case ICK_Fixed_Point_Conversion:
4529 assert((FromType->isFixedPointType() || ToType->isFixedPointType()) &&
4530 "Attempting implicit fixed point conversion without a fixed "
4531 "point operand");
4532 if (FromType->isFloatingType())
4533 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_FloatingToFixedPoint,
4534 VK: VK_PRValue,
4535 /*BasePath=*/nullptr, CCK).get();
4536 else if (ToType->isFloatingType())
4537 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_FixedPointToFloating,
4538 VK: VK_PRValue,
4539 /*BasePath=*/nullptr, CCK).get();
4540 else if (FromType->isIntegralType(Ctx: Context))
4541 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_IntegralToFixedPoint,
4542 VK: VK_PRValue,
4543 /*BasePath=*/nullptr, CCK).get();
4544 else if (ToType->isIntegralType(Ctx: Context))
4545 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_FixedPointToIntegral,
4546 VK: VK_PRValue,
4547 /*BasePath=*/nullptr, CCK).get();
4548 else if (ToType->isBooleanType())
4549 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_FixedPointToBoolean,
4550 VK: VK_PRValue,
4551 /*BasePath=*/nullptr, CCK).get();
4552 else
4553 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_FixedPointCast,
4554 VK: VK_PRValue,
4555 /*BasePath=*/nullptr, CCK).get();
4556 break;
4557
4558 case ICK_Compatible_Conversion:
4559 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_NoOp, VK: From->getValueKind(),
4560 /*BasePath=*/nullptr, CCK).get();
4561 break;
4562
4563 case ICK_Writeback_Conversion:
4564 case ICK_Pointer_Conversion: {
4565 if (SCS.IncompatibleObjC && Action != AA_Casting) {
4566 // Diagnose incompatible Objective-C conversions
4567 if (Action == AA_Initializing || Action == AA_Assigning)
4568 Diag(Loc: From->getBeginLoc(),
4569 DiagID: diag::ext_typecheck_convert_incompatible_pointer)
4570 << ToType << From->getType() << Action << From->getSourceRange()
4571 << 0;
4572 else
4573 Diag(Loc: From->getBeginLoc(),
4574 DiagID: diag::ext_typecheck_convert_incompatible_pointer)
4575 << From->getType() << ToType << Action << From->getSourceRange()
4576 << 0;
4577
4578 if (From->getType()->isObjCObjectPointerType() &&
4579 ToType->isObjCObjectPointerType())
4580 ObjC().EmitRelatedResultTypeNote(E: From);
4581 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
4582 !ObjC().CheckObjCARCUnavailableWeakConversion(castType: ToType,
4583 ExprType: From->getType())) {
4584 if (Action == AA_Initializing)
4585 Diag(Loc: From->getBeginLoc(), DiagID: diag::err_arc_weak_unavailable_assign);
4586 else
4587 Diag(Loc: From->getBeginLoc(), DiagID: diag::err_arc_convesion_of_weak_unavailable)
4588 << (Action == AA_Casting) << From->getType() << ToType
4589 << From->getSourceRange();
4590 }
4591
4592 // Defer address space conversion to the third conversion.
4593 QualType FromPteeType = From->getType()->getPointeeType();
4594 QualType ToPteeType = ToType->getPointeeType();
4595 QualType NewToType = ToType;
4596 if (!FromPteeType.isNull() && !ToPteeType.isNull() &&
4597 FromPteeType.getAddressSpace() != ToPteeType.getAddressSpace()) {
4598 NewToType = Context.removeAddrSpaceQualType(T: ToPteeType);
4599 NewToType = Context.getAddrSpaceQualType(T: NewToType,
4600 AddressSpace: FromPteeType.getAddressSpace());
4601 if (ToType->isObjCObjectPointerType())
4602 NewToType = Context.getObjCObjectPointerType(OIT: NewToType);
4603 else if (ToType->isBlockPointerType())
4604 NewToType = Context.getBlockPointerType(T: NewToType);
4605 else
4606 NewToType = Context.getPointerType(T: NewToType);
4607 }
4608
4609 CastKind Kind;
4610 CXXCastPath BasePath;
4611 if (CheckPointerConversion(From, ToType: NewToType, Kind, BasePath, IgnoreBaseAccess: CStyle))
4612 return ExprError();
4613
4614 // Make sure we extend blocks if necessary.
4615 // FIXME: doing this here is really ugly.
4616 if (Kind == CK_BlockPointerToObjCPointerCast) {
4617 ExprResult E = From;
4618 (void)ObjC().PrepareCastToObjCObjectPointer(E);
4619 From = E.get();
4620 }
4621 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
4622 ObjC().CheckObjCConversion(castRange: SourceRange(), castType: NewToType, op&: From, CCK);
4623 From = ImpCastExprToType(E: From, Type: NewToType, CK: Kind, VK: VK_PRValue, BasePath: &BasePath, CCK)
4624 .get();
4625 break;
4626 }
4627
4628 case ICK_Pointer_Member: {
4629 CastKind Kind;
4630 CXXCastPath BasePath;
4631 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, IgnoreBaseAccess: CStyle))
4632 return ExprError();
4633 if (CheckExceptionSpecCompatibility(From, ToType))
4634 return ExprError();
4635
4636 // We may not have been able to figure out what this member pointer resolved
4637 // to up until this exact point. Attempt to lock-in it's inheritance model.
4638 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
4639 (void)isCompleteType(Loc: From->getExprLoc(), T: From->getType());
4640 (void)isCompleteType(Loc: From->getExprLoc(), T: ToType);
4641 }
4642
4643 From =
4644 ImpCastExprToType(E: From, Type: ToType, CK: Kind, VK: VK_PRValue, BasePath: &BasePath, CCK).get();
4645 break;
4646 }
4647
4648 case ICK_Boolean_Conversion: {
4649 // Perform half-to-boolean conversion via float.
4650 if (From->getType()->isHalfType()) {
4651 From = ImpCastExprToType(E: From, Type: Context.FloatTy, CK: CK_FloatingCast).get();
4652 FromType = Context.FloatTy;
4653 }
4654 QualType ElTy = FromType;
4655 QualType StepTy = ToType;
4656 if (FromType->isVectorType()) {
4657 if (getLangOpts().HLSL)
4658 StepTy = adjustVectorType(Context, FromTy: FromType, ToType);
4659 ElTy = FromType->castAs<VectorType>()->getElementType();
4660 }
4661
4662 From = ImpCastExprToType(E: From, Type: StepTy, CK: ScalarTypeToBooleanCastKind(ScalarTy: ElTy),
4663 VK: VK_PRValue,
4664 /*BasePath=*/nullptr, CCK)
4665 .get();
4666 break;
4667 }
4668
4669 case ICK_Derived_To_Base: {
4670 CXXCastPath BasePath;
4671 if (CheckDerivedToBaseConversion(
4672 Derived: From->getType(), Base: ToType.getNonReferenceType(), Loc: From->getBeginLoc(),
4673 Range: From->getSourceRange(), BasePath: &BasePath, IgnoreAccess: CStyle))
4674 return ExprError();
4675
4676 From = ImpCastExprToType(E: From, Type: ToType.getNonReferenceType(),
4677 CK: CK_DerivedToBase, VK: From->getValueKind(),
4678 BasePath: &BasePath, CCK).get();
4679 break;
4680 }
4681
4682 case ICK_Vector_Conversion:
4683 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_BitCast, VK: VK_PRValue,
4684 /*BasePath=*/nullptr, CCK)
4685 .get();
4686 break;
4687
4688 case ICK_SVE_Vector_Conversion:
4689 case ICK_RVV_Vector_Conversion:
4690 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_BitCast, VK: VK_PRValue,
4691 /*BasePath=*/nullptr, CCK)
4692 .get();
4693 break;
4694
4695 case ICK_Vector_Splat: {
4696 // Vector splat from any arithmetic type to a vector.
4697 Expr *Elem = prepareVectorSplat(VectorTy: ToType, SplattedExpr: From).get();
4698 From = ImpCastExprToType(E: Elem, Type: ToType, CK: CK_VectorSplat, VK: VK_PRValue,
4699 /*BasePath=*/nullptr, CCK)
4700 .get();
4701 break;
4702 }
4703
4704 case ICK_Complex_Real:
4705 // Case 1. x -> _Complex y
4706 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
4707 QualType ElType = ToComplex->getElementType();
4708 bool isFloatingComplex = ElType->isRealFloatingType();
4709
4710 // x -> y
4711 if (Context.hasSameUnqualifiedType(T1: ElType, T2: From->getType())) {
4712 // do nothing
4713 } else if (From->getType()->isRealFloatingType()) {
4714 From = ImpCastExprToType(E: From, Type: ElType,
4715 CK: isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
4716 } else {
4717 assert(From->getType()->isIntegerType());
4718 From = ImpCastExprToType(E: From, Type: ElType,
4719 CK: isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
4720 }
4721 // y -> _Complex y
4722 From = ImpCastExprToType(E: From, Type: ToType,
4723 CK: isFloatingComplex ? CK_FloatingRealToComplex
4724 : CK_IntegralRealToComplex).get();
4725
4726 // Case 2. _Complex x -> y
4727 } else {
4728 auto *FromComplex = From->getType()->castAs<ComplexType>();
4729 QualType ElType = FromComplex->getElementType();
4730 bool isFloatingComplex = ElType->isRealFloatingType();
4731
4732 // _Complex x -> x
4733 From = ImpCastExprToType(E: From, Type: ElType,
4734 CK: isFloatingComplex ? CK_FloatingComplexToReal
4735 : CK_IntegralComplexToReal,
4736 VK: VK_PRValue, /*BasePath=*/nullptr, CCK)
4737 .get();
4738
4739 // x -> y
4740 if (Context.hasSameUnqualifiedType(T1: ElType, T2: ToType)) {
4741 // do nothing
4742 } else if (ToType->isRealFloatingType()) {
4743 From = ImpCastExprToType(E: From, Type: ToType,
4744 CK: isFloatingComplex ? CK_FloatingCast
4745 : CK_IntegralToFloating,
4746 VK: VK_PRValue, /*BasePath=*/nullptr, CCK)
4747 .get();
4748 } else {
4749 assert(ToType->isIntegerType());
4750 From = ImpCastExprToType(E: From, Type: ToType,
4751 CK: isFloatingComplex ? CK_FloatingToIntegral
4752 : CK_IntegralCast,
4753 VK: VK_PRValue, /*BasePath=*/nullptr, CCK)
4754 .get();
4755 }
4756 }
4757 break;
4758
4759 case ICK_Block_Pointer_Conversion: {
4760 LangAS AddrSpaceL =
4761 ToType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4762 LangAS AddrSpaceR =
4763 FromType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4764 assert(Qualifiers::isAddressSpaceSupersetOf(AddrSpaceL, AddrSpaceR) &&
4765 "Invalid cast");
4766 CastKind Kind =
4767 AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
4768 From = ImpCastExprToType(E: From, Type: ToType.getUnqualifiedType(), CK: Kind,
4769 VK: VK_PRValue, /*BasePath=*/nullptr, CCK)
4770 .get();
4771 break;
4772 }
4773
4774 case ICK_TransparentUnionConversion: {
4775 ExprResult FromRes = From;
4776 Sema::AssignConvertType ConvTy =
4777 CheckTransparentUnionArgumentConstraints(ArgType: ToType, RHS&: FromRes);
4778 if (FromRes.isInvalid())
4779 return ExprError();
4780 From = FromRes.get();
4781 assert ((ConvTy == Sema::Compatible) &&
4782 "Improper transparent union conversion");
4783 (void)ConvTy;
4784 break;
4785 }
4786
4787 case ICK_Zero_Event_Conversion:
4788 case ICK_Zero_Queue_Conversion:
4789 From = ImpCastExprToType(E: From, Type: ToType,
4790 CK: CK_ZeroToOCLOpaqueType,
4791 VK: From->getValueKind()).get();
4792 break;
4793
4794 case ICK_Lvalue_To_Rvalue:
4795 case ICK_Array_To_Pointer:
4796 case ICK_Function_To_Pointer:
4797 case ICK_Function_Conversion:
4798 case ICK_Qualification:
4799 case ICK_Num_Conversion_Kinds:
4800 case ICK_C_Only_Conversion:
4801 case ICK_Incompatible_Pointer_Conversion:
4802 case ICK_HLSL_Array_RValue:
4803 case ICK_HLSL_Vector_Truncation:
4804 case ICK_HLSL_Vector_Splat:
4805 llvm_unreachable("Improper second standard conversion");
4806 }
4807
4808 if (SCS.Dimension != ICK_Identity) {
4809 // If SCS.Element is not ICK_Identity the To and From types must be HLSL
4810 // vectors or matrices.
4811
4812 // TODO: Support HLSL matrices.
4813 assert((!From->getType()->isMatrixType() && !ToType->isMatrixType()) &&
4814 "Dimension conversion for matrix types is not implemented yet.");
4815 assert(ToType->isVectorType() &&
4816 "Dimension conversion is only supported for vector types.");
4817 switch (SCS.Dimension) {
4818 case ICK_HLSL_Vector_Splat: {
4819 // Vector splat from any arithmetic type to a vector.
4820 Expr *Elem = prepareVectorSplat(VectorTy: ToType, SplattedExpr: From).get();
4821 From = ImpCastExprToType(E: Elem, Type: ToType, CK: CK_VectorSplat, VK: VK_PRValue,
4822 /*BasePath=*/nullptr, CCK)
4823 .get();
4824 break;
4825 }
4826 case ICK_HLSL_Vector_Truncation: {
4827 // Note: HLSL built-in vectors are ExtVectors. Since this truncates a
4828 // vector to a smaller vector, this can only operate on arguments where
4829 // the source and destination types are ExtVectors.
4830 assert(From->getType()->isExtVectorType() && ToType->isExtVectorType() &&
4831 "HLSL vector truncation should only apply to ExtVectors");
4832 auto *FromVec = From->getType()->castAs<VectorType>();
4833 auto *ToVec = ToType->castAs<VectorType>();
4834 QualType ElType = FromVec->getElementType();
4835 QualType TruncTy =
4836 Context.getExtVectorType(VectorType: ElType, NumElts: ToVec->getNumElements());
4837 From = ImpCastExprToType(E: From, Type: TruncTy, CK: CK_HLSLVectorTruncation,
4838 VK: From->getValueKind())
4839 .get();
4840 break;
4841 }
4842 case ICK_Identity:
4843 default:
4844 llvm_unreachable("Improper element standard conversion");
4845 }
4846 }
4847
4848 switch (SCS.Third) {
4849 case ICK_Identity:
4850 // Nothing to do.
4851 break;
4852
4853 case ICK_Function_Conversion:
4854 // If both sides are functions (or pointers/references to them), there could
4855 // be incompatible exception declarations.
4856 if (CheckExceptionSpecCompatibility(From, ToType))
4857 return ExprError();
4858
4859 From = ImpCastExprToType(E: From, Type: ToType, CK: CK_NoOp, VK: VK_PRValue,
4860 /*BasePath=*/nullptr, CCK)
4861 .get();
4862 break;
4863
4864 case ICK_Qualification: {
4865 ExprValueKind VK = From->getValueKind();
4866 CastKind CK = CK_NoOp;
4867
4868 if (ToType->isReferenceType() &&
4869 ToType->getPointeeType().getAddressSpace() !=
4870 From->getType().getAddressSpace())
4871 CK = CK_AddressSpaceConversion;
4872
4873 if (ToType->isPointerType() &&
4874 ToType->getPointeeType().getAddressSpace() !=
4875 From->getType()->getPointeeType().getAddressSpace())
4876 CK = CK_AddressSpaceConversion;
4877
4878 if (!isCast(CCK) &&
4879 !ToType->getPointeeType().getQualifiers().hasUnaligned() &&
4880 From->getType()->getPointeeType().getQualifiers().hasUnaligned()) {
4881 Diag(Loc: From->getBeginLoc(), DiagID: diag::warn_imp_cast_drops_unaligned)
4882 << InitialFromType << ToType;
4883 }
4884
4885 From = ImpCastExprToType(E: From, Type: ToType.getNonLValueExprType(Context), CK, VK,
4886 /*BasePath=*/nullptr, CCK)
4887 .get();
4888
4889 if (SCS.DeprecatedStringLiteralToCharPtr &&
4890 !getLangOpts().WritableStrings) {
4891 Diag(Loc: From->getBeginLoc(),
4892 DiagID: getLangOpts().CPlusPlus11
4893 ? diag::ext_deprecated_string_literal_conversion
4894 : diag::warn_deprecated_string_literal_conversion)
4895 << ToType.getNonReferenceType();
4896 }
4897
4898 break;
4899 }
4900
4901 default:
4902 llvm_unreachable("Improper third standard conversion");
4903 }
4904
4905 // If this conversion sequence involved a scalar -> atomic conversion, perform
4906 // that conversion now.
4907 if (!ToAtomicType.isNull()) {
4908 assert(Context.hasSameType(
4909 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
4910 From = ImpCastExprToType(E: From, Type: ToAtomicType, CK: CK_NonAtomicToAtomic,
4911 VK: VK_PRValue, BasePath: nullptr, CCK)
4912 .get();
4913 }
4914
4915 // Materialize a temporary if we're implicitly converting to a reference
4916 // type. This is not required by the C++ rules but is necessary to maintain
4917 // AST invariants.
4918 if (ToType->isReferenceType() && From->isPRValue()) {
4919 ExprResult Res = TemporaryMaterializationConversion(E: From);
4920 if (Res.isInvalid())
4921 return ExprError();
4922 From = Res.get();
4923 }
4924
4925 // If this conversion sequence succeeded and involved implicitly converting a
4926 // _Nullable type to a _Nonnull one, complain.
4927 if (!isCast(CCK))
4928 diagnoseNullableToNonnullConversion(DstType: ToType, SrcType: InitialFromType,
4929 Loc: From->getBeginLoc());
4930
4931 return From;
4932}
4933
4934/// Checks that type T is not a VLA.
4935///
4936/// @returns @c true if @p T is VLA and a diagnostic was emitted,
4937/// @c false otherwise.
4938static bool DiagnoseVLAInCXXTypeTrait(Sema &S, const TypeSourceInfo *T,
4939 clang::tok::TokenKind TypeTraitID) {
4940 if (!T->getType()->isVariableArrayType())
4941 return false;
4942
4943 S.Diag(Loc: T->getTypeLoc().getBeginLoc(), DiagID: diag::err_vla_unsupported)
4944 << 1 << TypeTraitID;
4945 return true;
4946}
4947
4948/// Check the completeness of a type in a unary type trait.
4949///
4950/// If the particular type trait requires a complete type, tries to complete
4951/// it. If completing the type fails, a diagnostic is emitted and false
4952/// returned. If completing the type succeeds or no completion was required,
4953/// returns true.
4954static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
4955 SourceLocation Loc,
4956 QualType ArgTy) {
4957 // C++0x [meta.unary.prop]p3:
4958 // For all of the class templates X declared in this Clause, instantiating
4959 // that template with a template argument that is a class template
4960 // specialization may result in the implicit instantiation of the template
4961 // argument if and only if the semantics of X require that the argument
4962 // must be a complete type.
4963 // We apply this rule to all the type trait expressions used to implement
4964 // these class templates. We also try to follow any GCC documented behavior
4965 // in these expressions to ensure portability of standard libraries.
4966 switch (UTT) {
4967 default: llvm_unreachable("not a UTT");
4968 // is_complete_type somewhat obviously cannot require a complete type.
4969 case UTT_IsCompleteType:
4970 // Fall-through
4971
4972 // These traits are modeled on the type predicates in C++0x
4973 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4974 // requiring a complete type, as whether or not they return true cannot be
4975 // impacted by the completeness of the type.
4976 case UTT_IsVoid:
4977 case UTT_IsIntegral:
4978 case UTT_IsFloatingPoint:
4979 case UTT_IsArray:
4980 case UTT_IsBoundedArray:
4981 case UTT_IsPointer:
4982 case UTT_IsNullPointer:
4983 case UTT_IsReferenceable:
4984 case UTT_IsLvalueReference:
4985 case UTT_IsRvalueReference:
4986 case UTT_IsMemberFunctionPointer:
4987 case UTT_IsMemberObjectPointer:
4988 case UTT_IsEnum:
4989 case UTT_IsScopedEnum:
4990 case UTT_IsUnion:
4991 case UTT_IsClass:
4992 case UTT_IsFunction:
4993 case UTT_IsReference:
4994 case UTT_IsArithmetic:
4995 case UTT_IsFundamental:
4996 case UTT_IsObject:
4997 case UTT_IsScalar:
4998 case UTT_IsCompound:
4999 case UTT_IsMemberPointer:
5000 // Fall-through
5001
5002 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
5003 // which requires some of its traits to have the complete type. However,
5004 // the completeness of the type cannot impact these traits' semantics, and
5005 // so they don't require it. This matches the comments on these traits in
5006 // Table 49.
5007 case UTT_IsConst:
5008 case UTT_IsVolatile:
5009 case UTT_IsSigned:
5010 case UTT_IsUnboundedArray:
5011 case UTT_IsUnsigned:
5012
5013 // This type trait always returns false, checking the type is moot.
5014 case UTT_IsInterfaceClass:
5015 return true;
5016
5017 // C++14 [meta.unary.prop]:
5018 // If T is a non-union class type, T shall be a complete type.
5019 case UTT_IsEmpty:
5020 case UTT_IsPolymorphic:
5021 case UTT_IsAbstract:
5022 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
5023 if (!RD->isUnion())
5024 return !S.RequireCompleteType(
5025 Loc, T: ArgTy, DiagID: diag::err_incomplete_type_used_in_type_trait_expr);
5026 return true;
5027
5028 // C++14 [meta.unary.prop]:
5029 // If T is a class type, T shall be a complete type.
5030 case UTT_IsFinal:
5031 case UTT_IsSealed:
5032 if (ArgTy->getAsCXXRecordDecl())
5033 return !S.RequireCompleteType(
5034 Loc, T: ArgTy, DiagID: diag::err_incomplete_type_used_in_type_trait_expr);
5035 return true;
5036
5037 // LWG3823: T shall be an array type, a complete type, or cv void.
5038 case UTT_IsAggregate:
5039 if (ArgTy->isArrayType() || ArgTy->isVoidType())
5040 return true;
5041
5042 return !S.RequireCompleteType(
5043 Loc, T: ArgTy, DiagID: diag::err_incomplete_type_used_in_type_trait_expr);
5044
5045 // C++1z [meta.unary.prop]:
5046 // remove_all_extents_t<T> shall be a complete type or cv void.
5047 case UTT_IsTrivial:
5048 case UTT_IsTriviallyCopyable:
5049 case UTT_IsStandardLayout:
5050 case UTT_IsPOD:
5051 case UTT_IsLiteral:
5052 case UTT_IsBitwiseCloneable:
5053 // By analogy, is_trivially_relocatable and is_trivially_equality_comparable
5054 // impose the same constraints.
5055 case UTT_IsTriviallyRelocatable:
5056 case UTT_IsTriviallyEqualityComparable:
5057 case UTT_CanPassInRegs:
5058 // Per the GCC type traits documentation, T shall be a complete type, cv void,
5059 // or an array of unknown bound. But GCC actually imposes the same constraints
5060 // as above.
5061 case UTT_HasNothrowAssign:
5062 case UTT_HasNothrowMoveAssign:
5063 case UTT_HasNothrowConstructor:
5064 case UTT_HasNothrowCopy:
5065 case UTT_HasTrivialAssign:
5066 case UTT_HasTrivialMoveAssign:
5067 case UTT_HasTrivialDefaultConstructor:
5068 case UTT_HasTrivialMoveConstructor:
5069 case UTT_HasTrivialCopy:
5070 case UTT_HasTrivialDestructor:
5071 case UTT_HasVirtualDestructor:
5072 // has_unique_object_representations<T> when T is an array is defined in terms
5073 // of has_unique_object_representations<remove_all_extents_t<T>>, so the base
5074 // type needs to be complete even if the type is an incomplete array type.
5075 case UTT_HasUniqueObjectRepresentations:
5076 ArgTy = QualType(ArgTy->getBaseElementTypeUnsafe(), 0);
5077 [[fallthrough]];
5078
5079 // C++1z [meta.unary.prop]:
5080 // T shall be a complete type, cv void, or an array of unknown bound.
5081 case UTT_IsDestructible:
5082 case UTT_IsNothrowDestructible:
5083 case UTT_IsTriviallyDestructible:
5084 if (ArgTy->isIncompleteArrayType() || ArgTy->isVoidType())
5085 return true;
5086
5087 return !S.RequireCompleteType(
5088 Loc, T: ArgTy, DiagID: diag::err_incomplete_type_used_in_type_trait_expr);
5089 }
5090}
5091
5092static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
5093 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
5094 bool (CXXRecordDecl::*HasTrivial)() const,
5095 bool (CXXRecordDecl::*HasNonTrivial)() const,
5096 bool (CXXMethodDecl::*IsDesiredOp)() const)
5097{
5098 CXXRecordDecl *RD = cast<CXXRecordDecl>(Val: RT->getDecl());
5099 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
5100 return true;
5101
5102 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
5103 DeclarationNameInfo NameInfo(Name, KeyLoc);
5104 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
5105 if (Self.LookupQualifiedName(R&: Res, LookupCtx: RD)) {
5106 bool FoundOperator = false;
5107 Res.suppressDiagnostics();
5108 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
5109 Op != OpEnd; ++Op) {
5110 if (isa<FunctionTemplateDecl>(Val: *Op))
5111 continue;
5112
5113 CXXMethodDecl *Operator = cast<CXXMethodDecl>(Val: *Op);
5114 if((Operator->*IsDesiredOp)()) {
5115 FoundOperator = true;
5116 auto *CPT = Operator->getType()->castAs<FunctionProtoType>();
5117 CPT = Self.ResolveExceptionSpec(Loc: KeyLoc, FPT: CPT);
5118 if (!CPT || !CPT->isNothrow())
5119 return false;
5120 }
5121 }
5122 return FoundOperator;
5123 }
5124 return false;
5125}
5126
5127static bool HasNonDeletedDefaultedEqualityComparison(Sema &S,
5128 const CXXRecordDecl *Decl,
5129 SourceLocation KeyLoc) {
5130 if (Decl->isUnion())
5131 return false;
5132 if (Decl->isLambda())
5133 return Decl->isCapturelessLambda();
5134
5135 {
5136 EnterExpressionEvaluationContext UnevaluatedContext(
5137 S, Sema::ExpressionEvaluationContext::Unevaluated);
5138 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
5139 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
5140
5141 // const ClassT& obj;
5142 OpaqueValueExpr Operand(
5143 KeyLoc,
5144 Decl->getTypeForDecl()->getCanonicalTypeUnqualified().withConst(),
5145 ExprValueKind::VK_LValue);
5146 UnresolvedSet<16> Functions;
5147 // obj == obj;
5148 S.LookupBinOp(S: S.TUScope, OpLoc: {}, Opc: BinaryOperatorKind::BO_EQ, Functions);
5149
5150 auto Result = S.CreateOverloadedBinOp(OpLoc: KeyLoc, Opc: BinaryOperatorKind::BO_EQ,
5151 Fns: Functions, LHS: &Operand, RHS: &Operand);
5152 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5153 return false;
5154
5155 const auto *CallExpr = dyn_cast<CXXOperatorCallExpr>(Val: Result.get());
5156 if (!CallExpr)
5157 return false;
5158 const auto *Callee = CallExpr->getDirectCallee();
5159 auto ParamT = Callee->getParamDecl(i: 0)->getType();
5160 if (!Callee->isDefaulted())
5161 return false;
5162 if (!ParamT->isReferenceType() && !Decl->isTriviallyCopyable())
5163 return false;
5164 if (ParamT.getNonReferenceType()->getUnqualifiedDesugaredType() !=
5165 Decl->getTypeForDecl())
5166 return false;
5167 }
5168
5169 return llvm::all_of(Range: Decl->bases(),
5170 P: [&](const CXXBaseSpecifier &BS) {
5171 if (const auto *RD = BS.getType()->getAsCXXRecordDecl())
5172 return HasNonDeletedDefaultedEqualityComparison(
5173 S, Decl: RD, KeyLoc);
5174 return true;
5175 }) &&
5176 llvm::all_of(Range: Decl->fields(), P: [&](const FieldDecl *FD) {
5177 auto Type = FD->getType();
5178 if (Type->isArrayType())
5179 Type = Type->getBaseElementTypeUnsafe()
5180 ->getCanonicalTypeUnqualified();
5181
5182 if (Type->isReferenceType() || Type->isEnumeralType())
5183 return false;
5184 if (const auto *RD = Type->getAsCXXRecordDecl())
5185 return HasNonDeletedDefaultedEqualityComparison(S, Decl: RD, KeyLoc);
5186 return true;
5187 });
5188}
5189
5190static bool isTriviallyEqualityComparableType(Sema &S, QualType Type, SourceLocation KeyLoc) {
5191 QualType CanonicalType = Type.getCanonicalType();
5192 if (CanonicalType->isIncompleteType() || CanonicalType->isDependentType() ||
5193 CanonicalType->isEnumeralType() || CanonicalType->isArrayType())
5194 return false;
5195
5196 if (const auto *RD = CanonicalType->getAsCXXRecordDecl()) {
5197 if (!HasNonDeletedDefaultedEqualityComparison(S, Decl: RD, KeyLoc))
5198 return false;
5199 }
5200
5201 return S.getASTContext().hasUniqueObjectRepresentations(
5202 Ty: CanonicalType, /*CheckIfTriviallyCopyable=*/false);
5203}
5204
5205static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
5206 SourceLocation KeyLoc,
5207 TypeSourceInfo *TInfo) {
5208 QualType T = TInfo->getType();
5209 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
5210
5211 ASTContext &C = Self.Context;
5212 switch(UTT) {
5213 default: llvm_unreachable("not a UTT");
5214 // Type trait expressions corresponding to the primary type category
5215 // predicates in C++0x [meta.unary.cat].
5216 case UTT_IsVoid:
5217 return T->isVoidType();
5218 case UTT_IsIntegral:
5219 return T->isIntegralType(Ctx: C);
5220 case UTT_IsFloatingPoint:
5221 return T->isFloatingType();
5222 case UTT_IsArray:
5223 // Zero-sized arrays aren't considered arrays in partial specializations,
5224 // so __is_array shouldn't consider them arrays either.
5225 if (const auto *CAT = C.getAsConstantArrayType(T))
5226 return CAT->getSize() != 0;
5227 return T->isArrayType();
5228 case UTT_IsBoundedArray:
5229 if (DiagnoseVLAInCXXTypeTrait(S&: Self, T: TInfo, TypeTraitID: tok::kw___is_bounded_array))
5230 return false;
5231 // Zero-sized arrays aren't considered arrays in partial specializations,
5232 // so __is_bounded_array shouldn't consider them arrays either.
5233 if (const auto *CAT = C.getAsConstantArrayType(T))
5234 return CAT->getSize() != 0;
5235 return T->isArrayType() && !T->isIncompleteArrayType();
5236 case UTT_IsUnboundedArray:
5237 if (DiagnoseVLAInCXXTypeTrait(S&: Self, T: TInfo, TypeTraitID: tok::kw___is_unbounded_array))
5238 return false;
5239 return T->isIncompleteArrayType();
5240 case UTT_IsPointer:
5241 return T->isAnyPointerType();
5242 case UTT_IsNullPointer:
5243 return T->isNullPtrType();
5244 case UTT_IsLvalueReference:
5245 return T->isLValueReferenceType();
5246 case UTT_IsRvalueReference:
5247 return T->isRValueReferenceType();
5248 case UTT_IsMemberFunctionPointer:
5249 return T->isMemberFunctionPointerType();
5250 case UTT_IsMemberObjectPointer:
5251 return T->isMemberDataPointerType();
5252 case UTT_IsEnum:
5253 return T->isEnumeralType();
5254 case UTT_IsScopedEnum:
5255 return T->isScopedEnumeralType();
5256 case UTT_IsUnion:
5257 return T->isUnionType();
5258 case UTT_IsClass:
5259 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
5260 case UTT_IsFunction:
5261 return T->isFunctionType();
5262
5263 // Type trait expressions which correspond to the convenient composition
5264 // predicates in C++0x [meta.unary.comp].
5265 case UTT_IsReference:
5266 return T->isReferenceType();
5267 case UTT_IsArithmetic:
5268 return T->isArithmeticType() && !T->isEnumeralType();
5269 case UTT_IsFundamental:
5270 return T->isFundamentalType();
5271 case UTT_IsObject:
5272 return T->isObjectType();
5273 case UTT_IsScalar:
5274 // Note: semantic analysis depends on Objective-C lifetime types to be
5275 // considered scalar types. However, such types do not actually behave
5276 // like scalar types at run time (since they may require retain/release
5277 // operations), so we report them as non-scalar.
5278 if (T->isObjCLifetimeType()) {
5279 switch (T.getObjCLifetime()) {
5280 case Qualifiers::OCL_None:
5281 case Qualifiers::OCL_ExplicitNone:
5282 return true;
5283
5284 case Qualifiers::OCL_Strong:
5285 case Qualifiers::OCL_Weak:
5286 case Qualifiers::OCL_Autoreleasing:
5287 return false;
5288 }
5289 }
5290
5291 return T->isScalarType();
5292 case UTT_IsCompound:
5293 return T->isCompoundType();
5294 case UTT_IsMemberPointer:
5295 return T->isMemberPointerType();
5296
5297 // Type trait expressions which correspond to the type property predicates
5298 // in C++0x [meta.unary.prop].
5299 case UTT_IsConst:
5300 return T.isConstQualified();
5301 case UTT_IsVolatile:
5302 return T.isVolatileQualified();
5303 case UTT_IsTrivial:
5304 return T.isTrivialType(Context: C);
5305 case UTT_IsTriviallyCopyable:
5306 return T.isTriviallyCopyableType(Context: C);
5307 case UTT_IsStandardLayout:
5308 return T->isStandardLayoutType();
5309 case UTT_IsPOD:
5310 return T.isPODType(Context: C);
5311 case UTT_IsLiteral:
5312 return T->isLiteralType(Ctx: C);
5313 case UTT_IsEmpty:
5314 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5315 return !RD->isUnion() && RD->isEmpty();
5316 return false;
5317 case UTT_IsPolymorphic:
5318 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5319 return !RD->isUnion() && RD->isPolymorphic();
5320 return false;
5321 case UTT_IsAbstract:
5322 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5323 return !RD->isUnion() && RD->isAbstract();
5324 return false;
5325 case UTT_IsAggregate:
5326 // Report vector extensions and complex types as aggregates because they
5327 // support aggregate initialization. GCC mirrors this behavior for vectors
5328 // but not _Complex.
5329 return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
5330 T->isAnyComplexType();
5331 // __is_interface_class only returns true when CL is invoked in /CLR mode and
5332 // even then only when it is used with the 'interface struct ...' syntax
5333 // Clang doesn't support /CLR which makes this type trait moot.
5334 case UTT_IsInterfaceClass:
5335 return false;
5336 case UTT_IsFinal:
5337 case UTT_IsSealed:
5338 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5339 return RD->hasAttr<FinalAttr>();
5340 return false;
5341 case UTT_IsSigned:
5342 // Enum types should always return false.
5343 // Floating points should always return true.
5344 return T->isFloatingType() ||
5345 (T->isSignedIntegerType() && !T->isEnumeralType());
5346 case UTT_IsUnsigned:
5347 // Enum types should always return false.
5348 return T->isUnsignedIntegerType() && !T->isEnumeralType();
5349
5350 // Type trait expressions which query classes regarding their construction,
5351 // destruction, and copying. Rather than being based directly on the
5352 // related type predicates in the standard, they are specified by both
5353 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
5354 // specifications.
5355 //
5356 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
5357 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
5358 //
5359 // Note that these builtins do not behave as documented in g++: if a class
5360 // has both a trivial and a non-trivial special member of a particular kind,
5361 // they return false! For now, we emulate this behavior.
5362 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
5363 // does not correctly compute triviality in the presence of multiple special
5364 // members of the same kind. Revisit this once the g++ bug is fixed.
5365 case UTT_HasTrivialDefaultConstructor:
5366 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5367 // If __is_pod (type) is true then the trait is true, else if type is
5368 // a cv class or union type (or array thereof) with a trivial default
5369 // constructor ([class.ctor]) then the trait is true, else it is false.
5370 if (T.isPODType(Context: C))
5371 return true;
5372 if (CXXRecordDecl *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl())
5373 return RD->hasTrivialDefaultConstructor() &&
5374 !RD->hasNonTrivialDefaultConstructor();
5375 return false;
5376 case UTT_HasTrivialMoveConstructor:
5377 // This trait is implemented by MSVC 2012 and needed to parse the
5378 // standard library headers. Specifically this is used as the logic
5379 // behind std::is_trivially_move_constructible (20.9.4.3).
5380 if (T.isPODType(Context: C))
5381 return true;
5382 if (CXXRecordDecl *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl())
5383 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
5384 return false;
5385 case UTT_HasTrivialCopy:
5386 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5387 // If __is_pod (type) is true or type is a reference type then
5388 // the trait is true, else if type is a cv class or union type
5389 // with a trivial copy constructor ([class.copy]) then the trait
5390 // is true, else it is false.
5391 if (T.isPODType(Context: C) || T->isReferenceType())
5392 return true;
5393 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5394 return RD->hasTrivialCopyConstructor() &&
5395 !RD->hasNonTrivialCopyConstructor();
5396 return false;
5397 case UTT_HasTrivialMoveAssign:
5398 // This trait is implemented by MSVC 2012 and needed to parse the
5399 // standard library headers. Specifically it is used as the logic
5400 // behind std::is_trivially_move_assignable (20.9.4.3)
5401 if (T.isPODType(Context: C))
5402 return true;
5403 if (CXXRecordDecl *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl())
5404 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
5405 return false;
5406 case UTT_HasTrivialAssign:
5407 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5408 // If type is const qualified or is a reference type then the
5409 // trait is false. Otherwise if __is_pod (type) is true then the
5410 // trait is true, else if type is a cv class or union type with
5411 // a trivial copy assignment ([class.copy]) then the trait is
5412 // true, else it is false.
5413 // Note: the const and reference restrictions are interesting,
5414 // given that const and reference members don't prevent a class
5415 // from having a trivial copy assignment operator (but do cause
5416 // errors if the copy assignment operator is actually used, q.v.
5417 // [class.copy]p12).
5418
5419 if (T.isConstQualified())
5420 return false;
5421 if (T.isPODType(Context: C))
5422 return true;
5423 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5424 return RD->hasTrivialCopyAssignment() &&
5425 !RD->hasNonTrivialCopyAssignment();
5426 return false;
5427 case UTT_IsDestructible:
5428 case UTT_IsTriviallyDestructible:
5429 case UTT_IsNothrowDestructible:
5430 // C++14 [meta.unary.prop]:
5431 // For reference types, is_destructible<T>::value is true.
5432 if (T->isReferenceType())
5433 return true;
5434
5435 // Objective-C++ ARC: autorelease types don't require destruction.
5436 if (T->isObjCLifetimeType() &&
5437 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
5438 return true;
5439
5440 // C++14 [meta.unary.prop]:
5441 // For incomplete types and function types, is_destructible<T>::value is
5442 // false.
5443 if (T->isIncompleteType() || T->isFunctionType())
5444 return false;
5445
5446 // A type that requires destruction (via a non-trivial destructor or ARC
5447 // lifetime semantics) is not trivially-destructible.
5448 if (UTT == UTT_IsTriviallyDestructible && T.isDestructedType())
5449 return false;
5450
5451 // C++14 [meta.unary.prop]:
5452 // For object types and given U equal to remove_all_extents_t<T>, if the
5453 // expression std::declval<U&>().~U() is well-formed when treated as an
5454 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
5455 if (auto *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl()) {
5456 CXXDestructorDecl *Destructor = Self.LookupDestructor(Class: RD);
5457 if (!Destructor)
5458 return false;
5459 // C++14 [dcl.fct.def.delete]p2:
5460 // A program that refers to a deleted function implicitly or
5461 // explicitly, other than to declare it, is ill-formed.
5462 if (Destructor->isDeleted())
5463 return false;
5464 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
5465 return false;
5466 if (UTT == UTT_IsNothrowDestructible) {
5467 auto *CPT = Destructor->getType()->castAs<FunctionProtoType>();
5468 CPT = Self.ResolveExceptionSpec(Loc: KeyLoc, FPT: CPT);
5469 if (!CPT || !CPT->isNothrow())
5470 return false;
5471 }
5472 }
5473 return true;
5474
5475 case UTT_HasTrivialDestructor:
5476 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5477 // If __is_pod (type) is true or type is a reference type
5478 // then the trait is true, else if type is a cv class or union
5479 // type (or array thereof) with a trivial destructor
5480 // ([class.dtor]) then the trait is true, else it is
5481 // false.
5482 if (T.isPODType(Context: C) || T->isReferenceType())
5483 return true;
5484
5485 // Objective-C++ ARC: autorelease types don't require destruction.
5486 if (T->isObjCLifetimeType() &&
5487 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
5488 return true;
5489
5490 if (CXXRecordDecl *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl())
5491 return RD->hasTrivialDestructor();
5492 return false;
5493 // TODO: Propagate nothrowness for implicitly declared special members.
5494 case UTT_HasNothrowAssign:
5495 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5496 // If type is const qualified or is a reference type then the
5497 // trait is false. Otherwise if __has_trivial_assign (type)
5498 // is true then the trait is true, else if type is a cv class
5499 // or union type with copy assignment operators that are known
5500 // not to throw an exception then the trait is true, else it is
5501 // false.
5502 if (C.getBaseElementType(QT: T).isConstQualified())
5503 return false;
5504 if (T->isReferenceType())
5505 return false;
5506 if (T.isPODType(Context: C) || T->isObjCLifetimeType())
5507 return true;
5508
5509 if (const RecordType *RT = T->getAs<RecordType>())
5510 return HasNoThrowOperator(RT, Op: OO_Equal, Self, KeyLoc, C,
5511 HasTrivial: &CXXRecordDecl::hasTrivialCopyAssignment,
5512 HasNonTrivial: &CXXRecordDecl::hasNonTrivialCopyAssignment,
5513 IsDesiredOp: &CXXMethodDecl::isCopyAssignmentOperator);
5514 return false;
5515 case UTT_HasNothrowMoveAssign:
5516 // This trait is implemented by MSVC 2012 and needed to parse the
5517 // standard library headers. Specifically this is used as the logic
5518 // behind std::is_nothrow_move_assignable (20.9.4.3).
5519 if (T.isPODType(Context: C))
5520 return true;
5521
5522 if (const RecordType *RT = C.getBaseElementType(QT: T)->getAs<RecordType>())
5523 return HasNoThrowOperator(RT, Op: OO_Equal, Self, KeyLoc, C,
5524 HasTrivial: &CXXRecordDecl::hasTrivialMoveAssignment,
5525 HasNonTrivial: &CXXRecordDecl::hasNonTrivialMoveAssignment,
5526 IsDesiredOp: &CXXMethodDecl::isMoveAssignmentOperator);
5527 return false;
5528 case UTT_HasNothrowCopy:
5529 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5530 // If __has_trivial_copy (type) is true then the trait is true, else
5531 // if type is a cv class or union type with copy constructors that are
5532 // known not to throw an exception then the trait is true, else it is
5533 // false.
5534 if (T.isPODType(Context: C) || T->isReferenceType() || T->isObjCLifetimeType())
5535 return true;
5536 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
5537 if (RD->hasTrivialCopyConstructor() &&
5538 !RD->hasNonTrivialCopyConstructor())
5539 return true;
5540
5541 bool FoundConstructor = false;
5542 unsigned FoundTQs;
5543 for (const auto *ND : Self.LookupConstructors(Class: RD)) {
5544 // A template constructor is never a copy constructor.
5545 // FIXME: However, it may actually be selected at the actual overload
5546 // resolution point.
5547 if (isa<FunctionTemplateDecl>(Val: ND->getUnderlyingDecl()))
5548 continue;
5549 // UsingDecl itself is not a constructor
5550 if (isa<UsingDecl>(Val: ND))
5551 continue;
5552 auto *Constructor = cast<CXXConstructorDecl>(Val: ND->getUnderlyingDecl());
5553 if (Constructor->isCopyConstructor(TypeQuals&: FoundTQs)) {
5554 FoundConstructor = true;
5555 auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5556 CPT = Self.ResolveExceptionSpec(Loc: KeyLoc, FPT: CPT);
5557 if (!CPT)
5558 return false;
5559 // TODO: check whether evaluating default arguments can throw.
5560 // For now, we'll be conservative and assume that they can throw.
5561 if (!CPT->isNothrow() || CPT->getNumParams() > 1)
5562 return false;
5563 }
5564 }
5565
5566 return FoundConstructor;
5567 }
5568 return false;
5569 case UTT_HasNothrowConstructor:
5570 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5571 // If __has_trivial_constructor (type) is true then the trait is
5572 // true, else if type is a cv class or union type (or array
5573 // thereof) with a default constructor that is known not to
5574 // throw an exception then the trait is true, else it is false.
5575 if (T.isPODType(Context: C) || T->isObjCLifetimeType())
5576 return true;
5577 if (CXXRecordDecl *RD = C.getBaseElementType(QT: T)->getAsCXXRecordDecl()) {
5578 if (RD->hasTrivialDefaultConstructor() &&
5579 !RD->hasNonTrivialDefaultConstructor())
5580 return true;
5581
5582 bool FoundConstructor = false;
5583 for (const auto *ND : Self.LookupConstructors(Class: RD)) {
5584 // FIXME: In C++0x, a constructor template can be a default constructor.
5585 if (isa<FunctionTemplateDecl>(Val: ND->getUnderlyingDecl()))
5586 continue;
5587 // UsingDecl itself is not a constructor
5588 if (isa<UsingDecl>(Val: ND))
5589 continue;
5590 auto *Constructor = cast<CXXConstructorDecl>(Val: ND->getUnderlyingDecl());
5591 if (Constructor->isDefaultConstructor()) {
5592 FoundConstructor = true;
5593 auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5594 CPT = Self.ResolveExceptionSpec(Loc: KeyLoc, FPT: CPT);
5595 if (!CPT)
5596 return false;
5597 // FIXME: check whether evaluating default arguments can throw.
5598 // For now, we'll be conservative and assume that they can throw.
5599 if (!CPT->isNothrow() || CPT->getNumParams() > 0)
5600 return false;
5601 }
5602 }
5603 return FoundConstructor;
5604 }
5605 return false;
5606 case UTT_HasVirtualDestructor:
5607 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5608 // If type is a class type with a virtual destructor ([class.dtor])
5609 // then the trait is true, else it is false.
5610 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5611 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(Class: RD))
5612 return Destructor->isVirtual();
5613 return false;
5614
5615 // These type trait expressions are modeled on the specifications for the
5616 // Embarcadero C++0x type trait functions:
5617 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
5618 case UTT_IsCompleteType:
5619 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
5620 // Returns True if and only if T is a complete type at the point of the
5621 // function call.
5622 return !T->isIncompleteType();
5623 case UTT_HasUniqueObjectRepresentations:
5624 return C.hasUniqueObjectRepresentations(Ty: T);
5625 case UTT_IsTriviallyRelocatable:
5626 return T.isTriviallyRelocatableType(Context: C);
5627 case UTT_IsBitwiseCloneable:
5628 return T.isBitwiseCloneableType(Context: C);
5629 case UTT_IsReferenceable:
5630 return T.isReferenceable();
5631 case UTT_CanPassInRegs:
5632 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl(); RD && !T.hasQualifiers())
5633 return RD->canPassInRegisters();
5634 Self.Diag(Loc: KeyLoc, DiagID: diag::err_builtin_pass_in_regs_non_class) << T;
5635 return false;
5636 case UTT_IsTriviallyEqualityComparable:
5637 return isTriviallyEqualityComparableType(S&: Self, Type: T, KeyLoc);
5638 }
5639}
5640
5641static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, const TypeSourceInfo *Lhs,
5642 const TypeSourceInfo *Rhs, SourceLocation KeyLoc);
5643
5644static ExprResult CheckConvertibilityForTypeTraits(
5645 Sema &Self, const TypeSourceInfo *Lhs, const TypeSourceInfo *Rhs,
5646 SourceLocation KeyLoc, llvm::BumpPtrAllocator &OpaqueExprAllocator) {
5647
5648 QualType LhsT = Lhs->getType();
5649 QualType RhsT = Rhs->getType();
5650
5651 // C++0x [meta.rel]p4:
5652 // Given the following function prototype:
5653 //
5654 // template <class T>
5655 // typename add_rvalue_reference<T>::type create();
5656 //
5657 // the predicate condition for a template specialization
5658 // is_convertible<From, To> shall be satisfied if and only if
5659 // the return expression in the following code would be
5660 // well-formed, including any implicit conversions to the return
5661 // type of the function:
5662 //
5663 // To test() {
5664 // return create<From>();
5665 // }
5666 //
5667 // Access checking is performed as if in a context unrelated to To and
5668 // From. Only the validity of the immediate context of the expression
5669 // of the return-statement (including conversions to the return type)
5670 // is considered.
5671 //
5672 // We model the initialization as a copy-initialization of a temporary
5673 // of the appropriate type, which for this expression is identical to the
5674 // return statement (since NRVO doesn't apply).
5675
5676 // Functions aren't allowed to return function or array types.
5677 if (RhsT->isFunctionType() || RhsT->isArrayType())
5678 return ExprError();
5679
5680 // A function definition requires a complete, non-abstract return type.
5681 if (!Self.isCompleteType(Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT) ||
5682 Self.isAbstractType(Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT))
5683 return ExprError();
5684
5685 // Compute the result of add_rvalue_reference.
5686 if (LhsT->isObjectType() || LhsT->isFunctionType())
5687 LhsT = Self.Context.getRValueReferenceType(T: LhsT);
5688
5689 // Build a fake source and destination for initialization.
5690 InitializedEntity To(InitializedEntity::InitializeTemporary(Type: RhsT));
5691 Expr *From = new (OpaqueExprAllocator.Allocate<OpaqueValueExpr>())
5692 OpaqueValueExpr(KeyLoc, LhsT.getNonLValueExprType(Context: Self.Context),
5693 Expr::getValueKindForType(T: LhsT));
5694 InitializationKind Kind =
5695 InitializationKind::CreateCopy(InitLoc: KeyLoc, EqualLoc: SourceLocation());
5696
5697 // Perform the initialization in an unevaluated context within a SFINAE
5698 // trap at translation unit scope.
5699 EnterExpressionEvaluationContext Unevaluated(
5700 Self, Sema::ExpressionEvaluationContext::Unevaluated);
5701 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5702 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5703 InitializationSequence Init(Self, To, Kind, From);
5704 if (Init.Failed())
5705 return ExprError();
5706
5707 ExprResult Result = Init.Perform(S&: Self, Entity: To, Kind, Args: From);
5708 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5709 return ExprError();
5710
5711 return Result;
5712}
5713
5714static bool EvaluateBooleanTypeTrait(Sema &S, TypeTrait Kind,
5715 SourceLocation KWLoc,
5716 ArrayRef<TypeSourceInfo *> Args,
5717 SourceLocation RParenLoc,
5718 bool IsDependent) {
5719 if (IsDependent)
5720 return false;
5721
5722 if (Kind <= UTT_Last)
5723 return EvaluateUnaryTypeTrait(Self&: S, UTT: Kind, KeyLoc: KWLoc, TInfo: Args[0]);
5724
5725 // Evaluate ReferenceBindsToTemporary and ReferenceConstructsFromTemporary
5726 // alongside the IsConstructible traits to avoid duplication.
5727 if (Kind <= BTT_Last && Kind != BTT_ReferenceBindsToTemporary &&
5728 Kind != BTT_ReferenceConstructsFromTemporary &&
5729 Kind != BTT_ReferenceConvertsFromTemporary)
5730 return EvaluateBinaryTypeTrait(Self&: S, BTT: Kind, Lhs: Args[0],
5731 Rhs: Args[1], KeyLoc: RParenLoc);
5732
5733 switch (Kind) {
5734 case clang::BTT_ReferenceBindsToTemporary:
5735 case clang::BTT_ReferenceConstructsFromTemporary:
5736 case clang::BTT_ReferenceConvertsFromTemporary:
5737 case clang::TT_IsConstructible:
5738 case clang::TT_IsNothrowConstructible:
5739 case clang::TT_IsTriviallyConstructible: {
5740 // C++11 [meta.unary.prop]:
5741 // is_trivially_constructible is defined as:
5742 //
5743 // is_constructible<T, Args...>::value is true and the variable
5744 // definition for is_constructible, as defined below, is known to call
5745 // no operation that is not trivial.
5746 //
5747 // The predicate condition for a template specialization
5748 // is_constructible<T, Args...> shall be satisfied if and only if the
5749 // following variable definition would be well-formed for some invented
5750 // variable t:
5751 //
5752 // T t(create<Args>()...);
5753 assert(!Args.empty());
5754
5755 // Precondition: T and all types in the parameter pack Args shall be
5756 // complete types, (possibly cv-qualified) void, or arrays of
5757 // unknown bound.
5758 for (const auto *TSI : Args) {
5759 QualType ArgTy = TSI->getType();
5760 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
5761 continue;
5762
5763 if (S.RequireCompleteType(Loc: KWLoc, T: ArgTy,
5764 DiagID: diag::err_incomplete_type_used_in_type_trait_expr))
5765 return false;
5766 }
5767
5768 // Make sure the first argument is not incomplete nor a function type.
5769 QualType T = Args[0]->getType();
5770 if (T->isIncompleteType() || T->isFunctionType())
5771 return false;
5772
5773 // Make sure the first argument is not an abstract type.
5774 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
5775 if (RD && RD->isAbstract())
5776 return false;
5777
5778 llvm::BumpPtrAllocator OpaqueExprAllocator;
5779 SmallVector<Expr *, 2> ArgExprs;
5780 ArgExprs.reserve(N: Args.size() - 1);
5781 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
5782 QualType ArgTy = Args[I]->getType();
5783 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
5784 ArgTy = S.Context.getRValueReferenceType(T: ArgTy);
5785 ArgExprs.push_back(
5786 Elt: new (OpaqueExprAllocator.Allocate<OpaqueValueExpr>())
5787 OpaqueValueExpr(Args[I]->getTypeLoc().getBeginLoc(),
5788 ArgTy.getNonLValueExprType(Context: S.Context),
5789 Expr::getValueKindForType(T: ArgTy)));
5790 }
5791
5792 // Perform the initialization in an unevaluated context within a SFINAE
5793 // trap at translation unit scope.
5794 EnterExpressionEvaluationContext Unevaluated(
5795 S, Sema::ExpressionEvaluationContext::Unevaluated);
5796 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
5797 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
5798 InitializedEntity To(
5799 InitializedEntity::InitializeTemporary(Context&: S.Context, TypeInfo: Args[0]));
5800 InitializationKind InitKind(
5801 Kind == clang::BTT_ReferenceConvertsFromTemporary
5802 ? InitializationKind::CreateCopy(InitLoc: KWLoc, EqualLoc: KWLoc)
5803 : InitializationKind::CreateDirect(InitLoc: KWLoc, LParenLoc: KWLoc, RParenLoc));
5804 InitializationSequence Init(S, To, InitKind, ArgExprs);
5805 if (Init.Failed())
5806 return false;
5807
5808 ExprResult Result = Init.Perform(S, Entity: To, Kind: InitKind, Args: ArgExprs);
5809 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5810 return false;
5811
5812 if (Kind == clang::TT_IsConstructible)
5813 return true;
5814
5815 if (Kind == clang::BTT_ReferenceBindsToTemporary ||
5816 Kind == clang::BTT_ReferenceConstructsFromTemporary ||
5817 Kind == clang::BTT_ReferenceConvertsFromTemporary) {
5818 if (!T->isReferenceType())
5819 return false;
5820
5821 if (!Init.isDirectReferenceBinding())
5822 return true;
5823
5824 if (Kind == clang::BTT_ReferenceBindsToTemporary)
5825 return false;
5826
5827 QualType U = Args[1]->getType();
5828 if (U->isReferenceType())
5829 return false;
5830
5831 TypeSourceInfo *TPtr = S.Context.CreateTypeSourceInfo(
5832 T: S.Context.getPointerType(T: T.getNonReferenceType()));
5833 TypeSourceInfo *UPtr = S.Context.CreateTypeSourceInfo(
5834 T: S.Context.getPointerType(T: U.getNonReferenceType()));
5835 return !CheckConvertibilityForTypeTraits(Self&: S, Lhs: UPtr, Rhs: TPtr, KeyLoc: RParenLoc,
5836 OpaqueExprAllocator)
5837 .isInvalid();
5838 }
5839
5840 if (Kind == clang::TT_IsNothrowConstructible)
5841 return S.canThrow(E: Result.get()) == CT_Cannot;
5842
5843 if (Kind == clang::TT_IsTriviallyConstructible) {
5844 // Under Objective-C ARC and Weak, if the destination has non-trivial
5845 // Objective-C lifetime, this is a non-trivial construction.
5846 if (T.getNonReferenceType().hasNonTrivialObjCLifetime())
5847 return false;
5848
5849 // The initialization succeeded; now make sure there are no non-trivial
5850 // calls.
5851 return !Result.get()->hasNonTrivialCall(Ctx: S.Context);
5852 }
5853
5854 llvm_unreachable("unhandled type trait");
5855 return false;
5856 }
5857 default: llvm_unreachable("not a TT");
5858 }
5859
5860 return false;
5861}
5862
5863namespace {
5864void DiagnoseBuiltinDeprecation(Sema& S, TypeTrait Kind,
5865 SourceLocation KWLoc) {
5866 TypeTrait Replacement;
5867 switch (Kind) {
5868 case UTT_HasNothrowAssign:
5869 case UTT_HasNothrowMoveAssign:
5870 Replacement = BTT_IsNothrowAssignable;
5871 break;
5872 case UTT_HasNothrowCopy:
5873 case UTT_HasNothrowConstructor:
5874 Replacement = TT_IsNothrowConstructible;
5875 break;
5876 case UTT_HasTrivialAssign:
5877 case UTT_HasTrivialMoveAssign:
5878 Replacement = BTT_IsTriviallyAssignable;
5879 break;
5880 case UTT_HasTrivialCopy:
5881 Replacement = UTT_IsTriviallyCopyable;
5882 break;
5883 case UTT_HasTrivialDefaultConstructor:
5884 case UTT_HasTrivialMoveConstructor:
5885 Replacement = TT_IsTriviallyConstructible;
5886 break;
5887 case UTT_HasTrivialDestructor:
5888 Replacement = UTT_IsTriviallyDestructible;
5889 break;
5890 default:
5891 return;
5892 }
5893 S.Diag(Loc: KWLoc, DiagID: diag::warn_deprecated_builtin)
5894 << getTraitSpelling(T: Kind) << getTraitSpelling(T: Replacement);
5895}
5896}
5897
5898bool Sema::CheckTypeTraitArity(unsigned Arity, SourceLocation Loc, size_t N) {
5899 if (Arity && N != Arity) {
5900 Diag(Loc, DiagID: diag::err_type_trait_arity)
5901 << Arity << 0 << (Arity > 1) << (int)N << SourceRange(Loc);
5902 return false;
5903 }
5904
5905 if (!Arity && N == 0) {
5906 Diag(Loc, DiagID: diag::err_type_trait_arity)
5907 << 1 << 1 << 1 << (int)N << SourceRange(Loc);
5908 return false;
5909 }
5910 return true;
5911}
5912
5913enum class TypeTraitReturnType {
5914 Bool,
5915};
5916
5917static TypeTraitReturnType GetReturnType(TypeTrait Kind) {
5918 return TypeTraitReturnType::Bool;
5919}
5920
5921ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
5922 ArrayRef<TypeSourceInfo *> Args,
5923 SourceLocation RParenLoc) {
5924 if (!CheckTypeTraitArity(Arity: getTypeTraitArity(T: Kind), Loc: KWLoc, N: Args.size()))
5925 return ExprError();
5926
5927 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
5928 S&: *this, UTT: Kind, Loc: KWLoc, ArgTy: Args[0]->getType()))
5929 return ExprError();
5930
5931 DiagnoseBuiltinDeprecation(S&: *this, Kind, KWLoc);
5932
5933 bool Dependent = false;
5934 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5935 if (Args[I]->getType()->isDependentType()) {
5936 Dependent = true;
5937 break;
5938 }
5939 }
5940
5941 switch (GetReturnType(Kind)) {
5942 case TypeTraitReturnType::Bool: {
5943 bool Result = EvaluateBooleanTypeTrait(S&: *this, Kind, KWLoc, Args, RParenLoc,
5944 IsDependent: Dependent);
5945 return TypeTraitExpr::Create(C: Context, T: Context.getLogicalOperationType(),
5946 Loc: KWLoc, Kind, Args, RParenLoc, Value: Result);
5947 }
5948 }
5949 llvm_unreachable("unhandled type trait return type");
5950}
5951
5952ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
5953 ArrayRef<ParsedType> Args,
5954 SourceLocation RParenLoc) {
5955 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
5956 ConvertedArgs.reserve(N: Args.size());
5957
5958 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5959 TypeSourceInfo *TInfo;
5960 QualType T = GetTypeFromParser(Ty: Args[I], TInfo: &TInfo);
5961 if (!TInfo)
5962 TInfo = Context.getTrivialTypeSourceInfo(T, Loc: KWLoc);
5963
5964 ConvertedArgs.push_back(Elt: TInfo);
5965 }
5966
5967 return BuildTypeTrait(Kind, KWLoc, Args: ConvertedArgs, RParenLoc);
5968}
5969
5970static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, const TypeSourceInfo *Lhs,
5971 const TypeSourceInfo *Rhs, SourceLocation KeyLoc) {
5972 QualType LhsT = Lhs->getType();
5973 QualType RhsT = Rhs->getType();
5974
5975 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
5976 "Cannot evaluate traits of dependent types");
5977
5978 switch(BTT) {
5979 case BTT_IsBaseOf: {
5980 // C++0x [meta.rel]p2
5981 // Base is a base class of Derived without regard to cv-qualifiers or
5982 // Base and Derived are not unions and name the same class type without
5983 // regard to cv-qualifiers.
5984
5985 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
5986 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
5987 if (!rhsRecord || !lhsRecord) {
5988 const ObjCObjectType *LHSObjTy = LhsT->getAs<ObjCObjectType>();
5989 const ObjCObjectType *RHSObjTy = RhsT->getAs<ObjCObjectType>();
5990 if (!LHSObjTy || !RHSObjTy)
5991 return false;
5992
5993 ObjCInterfaceDecl *BaseInterface = LHSObjTy->getInterface();
5994 ObjCInterfaceDecl *DerivedInterface = RHSObjTy->getInterface();
5995 if (!BaseInterface || !DerivedInterface)
5996 return false;
5997
5998 if (Self.RequireCompleteType(
5999 Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT,
6000 DiagID: diag::err_incomplete_type_used_in_type_trait_expr))
6001 return false;
6002
6003 return BaseInterface->isSuperClassOf(I: DerivedInterface);
6004 }
6005
6006 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
6007 == (lhsRecord == rhsRecord));
6008
6009 // Unions are never base classes, and never have base classes.
6010 // It doesn't matter if they are complete or not. See PR#41843
6011 if (lhsRecord && lhsRecord->getDecl()->isUnion())
6012 return false;
6013 if (rhsRecord && rhsRecord->getDecl()->isUnion())
6014 return false;
6015
6016 if (lhsRecord == rhsRecord)
6017 return true;
6018
6019 // C++0x [meta.rel]p2:
6020 // If Base and Derived are class types and are different types
6021 // (ignoring possible cv-qualifiers) then Derived shall be a
6022 // complete type.
6023 if (Self.RequireCompleteType(
6024 Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT,
6025 DiagID: diag::err_incomplete_type_used_in_type_trait_expr))
6026 return false;
6027
6028 return cast<CXXRecordDecl>(Val: rhsRecord->getDecl())
6029 ->isDerivedFrom(Base: cast<CXXRecordDecl>(Val: lhsRecord->getDecl()));
6030 }
6031 case BTT_IsSame:
6032 return Self.Context.hasSameType(T1: LhsT, T2: RhsT);
6033 case BTT_TypeCompatible: {
6034 // GCC ignores cv-qualifiers on arrays for this builtin.
6035 Qualifiers LhsQuals, RhsQuals;
6036 QualType Lhs = Self.getASTContext().getUnqualifiedArrayType(T: LhsT, Quals&: LhsQuals);
6037 QualType Rhs = Self.getASTContext().getUnqualifiedArrayType(T: RhsT, Quals&: RhsQuals);
6038 return Self.Context.typesAreCompatible(T1: Lhs, T2: Rhs);
6039 }
6040 case BTT_IsConvertible:
6041 case BTT_IsConvertibleTo:
6042 case BTT_IsNothrowConvertible: {
6043 if (RhsT->isVoidType())
6044 return LhsT->isVoidType();
6045 llvm::BumpPtrAllocator OpaqueExprAllocator;
6046 ExprResult Result = CheckConvertibilityForTypeTraits(Self, Lhs, Rhs, KeyLoc,
6047 OpaqueExprAllocator);
6048 if (Result.isInvalid())
6049 return false;
6050
6051 if (BTT != BTT_IsNothrowConvertible)
6052 return true;
6053
6054 return Self.canThrow(E: Result.get()) == CT_Cannot;
6055 }
6056
6057 case BTT_IsAssignable:
6058 case BTT_IsNothrowAssignable:
6059 case BTT_IsTriviallyAssignable: {
6060 // C++11 [meta.unary.prop]p3:
6061 // is_trivially_assignable is defined as:
6062 // is_assignable<T, U>::value is true and the assignment, as defined by
6063 // is_assignable, is known to call no operation that is not trivial
6064 //
6065 // is_assignable is defined as:
6066 // The expression declval<T>() = declval<U>() is well-formed when
6067 // treated as an unevaluated operand (Clause 5).
6068 //
6069 // For both, T and U shall be complete types, (possibly cv-qualified)
6070 // void, or arrays of unknown bound.
6071 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
6072 Self.RequireCompleteType(
6073 Loc: Lhs->getTypeLoc().getBeginLoc(), T: LhsT,
6074 DiagID: diag::err_incomplete_type_used_in_type_trait_expr))
6075 return false;
6076 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
6077 Self.RequireCompleteType(
6078 Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT,
6079 DiagID: diag::err_incomplete_type_used_in_type_trait_expr))
6080 return false;
6081
6082 // cv void is never assignable.
6083 if (LhsT->isVoidType() || RhsT->isVoidType())
6084 return false;
6085
6086 // Build expressions that emulate the effect of declval<T>() and
6087 // declval<U>().
6088 if (LhsT->isObjectType() || LhsT->isFunctionType())
6089 LhsT = Self.Context.getRValueReferenceType(T: LhsT);
6090 if (RhsT->isObjectType() || RhsT->isFunctionType())
6091 RhsT = Self.Context.getRValueReferenceType(T: RhsT);
6092 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Context: Self.Context),
6093 Expr::getValueKindForType(T: LhsT));
6094 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Context: Self.Context),
6095 Expr::getValueKindForType(T: RhsT));
6096
6097 // Attempt the assignment in an unevaluated context within a SFINAE
6098 // trap at translation unit scope.
6099 EnterExpressionEvaluationContext Unevaluated(
6100 Self, Sema::ExpressionEvaluationContext::Unevaluated);
6101 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
6102 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
6103 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, OpLoc: KeyLoc, Opc: BO_Assign, LHSExpr: &Lhs,
6104 RHSExpr: &Rhs);
6105 if (Result.isInvalid())
6106 return false;
6107
6108 // Treat the assignment as unused for the purpose of -Wdeprecated-volatile.
6109 Self.CheckUnusedVolatileAssignment(E: Result.get());
6110
6111 if (SFINAE.hasErrorOccurred())
6112 return false;
6113
6114 if (BTT == BTT_IsAssignable)
6115 return true;
6116
6117 if (BTT == BTT_IsNothrowAssignable)
6118 return Self.canThrow(E: Result.get()) == CT_Cannot;
6119
6120 if (BTT == BTT_IsTriviallyAssignable) {
6121 // Under Objective-C ARC and Weak, if the destination has non-trivial
6122 // Objective-C lifetime, this is a non-trivial assignment.
6123 if (LhsT.getNonReferenceType().hasNonTrivialObjCLifetime())
6124 return false;
6125
6126 return !Result.get()->hasNonTrivialCall(Ctx: Self.Context);
6127 }
6128
6129 llvm_unreachable("unhandled type trait");
6130 return false;
6131 }
6132 case BTT_IsLayoutCompatible: {
6133 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType())
6134 Self.RequireCompleteType(Loc: Lhs->getTypeLoc().getBeginLoc(), T: LhsT,
6135 DiagID: diag::err_incomplete_type);
6136 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType())
6137 Self.RequireCompleteType(Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT,
6138 DiagID: diag::err_incomplete_type);
6139
6140 DiagnoseVLAInCXXTypeTrait(S&: Self, T: Lhs, TypeTraitID: tok::kw___is_layout_compatible);
6141 DiagnoseVLAInCXXTypeTrait(S&: Self, T: Rhs, TypeTraitID: tok::kw___is_layout_compatible);
6142
6143 return Self.IsLayoutCompatible(T1: LhsT, T2: RhsT);
6144 }
6145 case BTT_IsPointerInterconvertibleBaseOf: {
6146 if (LhsT->isStructureOrClassType() && RhsT->isStructureOrClassType() &&
6147 !Self.getASTContext().hasSameUnqualifiedType(T1: LhsT, T2: RhsT)) {
6148 Self.RequireCompleteType(Loc: Rhs->getTypeLoc().getBeginLoc(), T: RhsT,
6149 DiagID: diag::err_incomplete_type);
6150 }
6151
6152 DiagnoseVLAInCXXTypeTrait(S&: Self, T: Lhs,
6153 TypeTraitID: tok::kw___is_pointer_interconvertible_base_of);
6154 DiagnoseVLAInCXXTypeTrait(S&: Self, T: Rhs,
6155 TypeTraitID: tok::kw___is_pointer_interconvertible_base_of);
6156
6157 return Self.IsPointerInterconvertibleBaseOf(Base: Lhs, Derived: Rhs);
6158 }
6159 case BTT_IsDeducible: {
6160 const auto *TSTToBeDeduced = cast<DeducedTemplateSpecializationType>(Val&: LhsT);
6161 sema::TemplateDeductionInfo Info(KeyLoc);
6162 return Self.DeduceTemplateArgumentsFromType(
6163 TD: TSTToBeDeduced->getTemplateName().getAsTemplateDecl(), FromType: RhsT,
6164 Info) == TemplateDeductionResult::Success;
6165 }
6166 default:
6167 llvm_unreachable("not a BTT");
6168 }
6169 llvm_unreachable("Unknown type trait or not implemented");
6170}
6171
6172ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
6173 SourceLocation KWLoc,
6174 ParsedType Ty,
6175 Expr* DimExpr,
6176 SourceLocation RParen) {
6177 TypeSourceInfo *TSInfo;
6178 QualType T = GetTypeFromParser(Ty, TInfo: &TSInfo);
6179 if (!TSInfo)
6180 TSInfo = Context.getTrivialTypeSourceInfo(T);
6181
6182 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
6183}
6184
6185static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
6186 QualType T, Expr *DimExpr,
6187 SourceLocation KeyLoc) {
6188 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
6189
6190 switch(ATT) {
6191 case ATT_ArrayRank:
6192 if (T->isArrayType()) {
6193 unsigned Dim = 0;
6194 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
6195 ++Dim;
6196 T = AT->getElementType();
6197 }
6198 return Dim;
6199 }
6200 return 0;
6201
6202 case ATT_ArrayExtent: {
6203 llvm::APSInt Value;
6204 uint64_t Dim;
6205 if (Self.VerifyIntegerConstantExpression(
6206 E: DimExpr, Result: &Value, DiagID: diag::err_dimension_expr_not_constant_integer)
6207 .isInvalid())
6208 return 0;
6209 if (Value.isSigned() && Value.isNegative()) {
6210 Self.Diag(Loc: KeyLoc, DiagID: diag::err_dimension_expr_not_constant_integer)
6211 << DimExpr->getSourceRange();
6212 return 0;
6213 }
6214 Dim = Value.getLimitedValue();
6215
6216 if (T->isArrayType()) {
6217 unsigned D = 0;
6218 bool Matched = false;
6219 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
6220 if (Dim == D) {
6221 Matched = true;
6222 break;
6223 }
6224 ++D;
6225 T = AT->getElementType();
6226 }
6227
6228 if (Matched && T->isArrayType()) {
6229 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
6230 return CAT->getLimitedSize();
6231 }
6232 }
6233 return 0;
6234 }
6235 }
6236 llvm_unreachable("Unknown type trait or not implemented");
6237}
6238
6239ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
6240 SourceLocation KWLoc,
6241 TypeSourceInfo *TSInfo,
6242 Expr* DimExpr,
6243 SourceLocation RParen) {
6244 QualType T = TSInfo->getType();
6245
6246 // FIXME: This should likely be tracked as an APInt to remove any host
6247 // assumptions about the width of size_t on the target.
6248 uint64_t Value = 0;
6249 if (!T->isDependentType())
6250 Value = EvaluateArrayTypeTrait(Self&: *this, ATT, T, DimExpr, KeyLoc: KWLoc);
6251
6252 // While the specification for these traits from the Embarcadero C++
6253 // compiler's documentation says the return type is 'unsigned int', Clang
6254 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
6255 // compiler, there is no difference. On several other platforms this is an
6256 // important distinction.
6257 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
6258 RParen, Context.getSizeType());
6259}
6260
6261ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
6262 SourceLocation KWLoc,
6263 Expr *Queried,
6264 SourceLocation RParen) {
6265 // If error parsing the expression, ignore.
6266 if (!Queried)
6267 return ExprError();
6268
6269 ExprResult Result = BuildExpressionTrait(OET: ET, KWLoc, Queried, RParen);
6270
6271 return Result;
6272}
6273
6274static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
6275 switch (ET) {
6276 case ET_IsLValueExpr: return E->isLValue();
6277 case ET_IsRValueExpr:
6278 return E->isPRValue();
6279 }
6280 llvm_unreachable("Expression trait not covered by switch");
6281}
6282
6283ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
6284 SourceLocation KWLoc,
6285 Expr *Queried,
6286 SourceLocation RParen) {
6287 if (Queried->isTypeDependent()) {
6288 // Delay type-checking for type-dependent expressions.
6289 } else if (Queried->hasPlaceholderType()) {
6290 ExprResult PE = CheckPlaceholderExpr(E: Queried);
6291 if (PE.isInvalid()) return ExprError();
6292 return BuildExpressionTrait(ET, KWLoc, Queried: PE.get(), RParen);
6293 }
6294
6295 bool Value = EvaluateExpressionTrait(ET, E: Queried);
6296
6297 return new (Context)
6298 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
6299}
6300
6301QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
6302 ExprValueKind &VK,
6303 SourceLocation Loc,
6304 bool isIndirect) {
6305 assert(!LHS.get()->hasPlaceholderType() && !RHS.get()->hasPlaceholderType() &&
6306 "placeholders should have been weeded out by now");
6307
6308 // The LHS undergoes lvalue conversions if this is ->*, and undergoes the
6309 // temporary materialization conversion otherwise.
6310 if (isIndirect)
6311 LHS = DefaultLvalueConversion(E: LHS.get());
6312 else if (LHS.get()->isPRValue())
6313 LHS = TemporaryMaterializationConversion(E: LHS.get());
6314 if (LHS.isInvalid())
6315 return QualType();
6316
6317 // The RHS always undergoes lvalue conversions.
6318 RHS = DefaultLvalueConversion(E: RHS.get());
6319 if (RHS.isInvalid()) return QualType();
6320
6321 const char *OpSpelling = isIndirect ? "->*" : ".*";
6322 // C++ 5.5p2
6323 // The binary operator .* [p3: ->*] binds its second operand, which shall
6324 // be of type "pointer to member of T" (where T is a completely-defined
6325 // class type) [...]
6326 QualType RHSType = RHS.get()->getType();
6327 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
6328 if (!MemPtr) {
6329 Diag(Loc, DiagID: diag::err_bad_memptr_rhs)
6330 << OpSpelling << RHSType << RHS.get()->getSourceRange();
6331 return QualType();
6332 }
6333
6334 QualType Class(MemPtr->getClass(), 0);
6335
6336 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
6337 // member pointer points must be completely-defined. However, there is no
6338 // reason for this semantic distinction, and the rule is not enforced by
6339 // other compilers. Therefore, we do not check this property, as it is
6340 // likely to be considered a defect.
6341
6342 // C++ 5.5p2
6343 // [...] to its first operand, which shall be of class T or of a class of
6344 // which T is an unambiguous and accessible base class. [p3: a pointer to
6345 // such a class]
6346 QualType LHSType = LHS.get()->getType();
6347 if (isIndirect) {
6348 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
6349 LHSType = Ptr->getPointeeType();
6350 else {
6351 Diag(Loc, DiagID: diag::err_bad_memptr_lhs)
6352 << OpSpelling << 1 << LHSType
6353 << FixItHint::CreateReplacement(RemoveRange: SourceRange(Loc), Code: ".*");
6354 return QualType();
6355 }
6356 }
6357
6358 if (!Context.hasSameUnqualifiedType(T1: Class, T2: LHSType)) {
6359 // If we want to check the hierarchy, we need a complete type.
6360 if (RequireCompleteType(Loc, T: LHSType, DiagID: diag::err_bad_memptr_lhs,
6361 Args: OpSpelling, Args: (int)isIndirect)) {
6362 return QualType();
6363 }
6364
6365 if (!IsDerivedFrom(Loc, Derived: LHSType, Base: Class)) {
6366 Diag(Loc, DiagID: diag::err_bad_memptr_lhs) << OpSpelling
6367 << (int)isIndirect << LHS.get()->getType();
6368 return QualType();
6369 }
6370
6371 CXXCastPath BasePath;
6372 if (CheckDerivedToBaseConversion(
6373 Derived: LHSType, Base: Class, Loc,
6374 Range: SourceRange(LHS.get()->getBeginLoc(), RHS.get()->getEndLoc()),
6375 BasePath: &BasePath))
6376 return QualType();
6377
6378 // Cast LHS to type of use.
6379 QualType UseType = Context.getQualifiedType(T: Class, Qs: LHSType.getQualifiers());
6380 if (isIndirect)
6381 UseType = Context.getPointerType(T: UseType);
6382 ExprValueKind VK = isIndirect ? VK_PRValue : LHS.get()->getValueKind();
6383 LHS = ImpCastExprToType(E: LHS.get(), Type: UseType, CK: CK_DerivedToBase, VK,
6384 BasePath: &BasePath);
6385 }
6386
6387 if (isa<CXXScalarValueInitExpr>(Val: RHS.get()->IgnoreParens())) {
6388 // Diagnose use of pointer-to-member type which when used as
6389 // the functional cast in a pointer-to-member expression.
6390 Diag(Loc, DiagID: diag::err_pointer_to_member_type) << isIndirect;
6391 return QualType();
6392 }
6393
6394 // C++ 5.5p2
6395 // The result is an object or a function of the type specified by the
6396 // second operand.
6397 // The cv qualifiers are the union of those in the pointer and the left side,
6398 // in accordance with 5.5p5 and 5.2.5.
6399 QualType Result = MemPtr->getPointeeType();
6400 Result = Context.getCVRQualifiedType(T: Result, CVR: LHSType.getCVRQualifiers());
6401
6402 // C++0x [expr.mptr.oper]p6:
6403 // In a .* expression whose object expression is an rvalue, the program is
6404 // ill-formed if the second operand is a pointer to member function with
6405 // ref-qualifier &. In a ->* expression or in a .* expression whose object
6406 // expression is an lvalue, the program is ill-formed if the second operand
6407 // is a pointer to member function with ref-qualifier &&.
6408 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
6409 switch (Proto->getRefQualifier()) {
6410 case RQ_None:
6411 // Do nothing
6412 break;
6413
6414 case RQ_LValue:
6415 if (!isIndirect && !LHS.get()->Classify(Ctx&: Context).isLValue()) {
6416 // C++2a allows functions with ref-qualifier & if their cv-qualifier-seq
6417 // is (exactly) 'const'.
6418 if (Proto->isConst() && !Proto->isVolatile())
6419 Diag(Loc, DiagID: getLangOpts().CPlusPlus20
6420 ? diag::warn_cxx17_compat_pointer_to_const_ref_member_on_rvalue
6421 : diag::ext_pointer_to_const_ref_member_on_rvalue);
6422 else
6423 Diag(Loc, DiagID: diag::err_pointer_to_member_oper_value_classify)
6424 << RHSType << 1 << LHS.get()->getSourceRange();
6425 }
6426 break;
6427
6428 case RQ_RValue:
6429 if (isIndirect || !LHS.get()->Classify(Ctx&: Context).isRValue())
6430 Diag(Loc, DiagID: diag::err_pointer_to_member_oper_value_classify)
6431 << RHSType << 0 << LHS.get()->getSourceRange();
6432 break;
6433 }
6434 }
6435
6436 // C++ [expr.mptr.oper]p6:
6437 // The result of a .* expression whose second operand is a pointer
6438 // to a data member is of the same value category as its
6439 // first operand. The result of a .* expression whose second
6440 // operand is a pointer to a member function is a prvalue. The
6441 // result of an ->* expression is an lvalue if its second operand
6442 // is a pointer to data member and a prvalue otherwise.
6443 if (Result->isFunctionType()) {
6444 VK = VK_PRValue;
6445 return Context.BoundMemberTy;
6446 } else if (isIndirect) {
6447 VK = VK_LValue;
6448 } else {
6449 VK = LHS.get()->getValueKind();
6450 }
6451
6452 return Result;
6453}
6454
6455/// Try to convert a type to another according to C++11 5.16p3.
6456///
6457/// This is part of the parameter validation for the ? operator. If either
6458/// value operand is a class type, the two operands are attempted to be
6459/// converted to each other. This function does the conversion in one direction.
6460/// It returns true if the program is ill-formed and has already been diagnosed
6461/// as such.
6462static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
6463 SourceLocation QuestionLoc,
6464 bool &HaveConversion,
6465 QualType &ToType) {
6466 HaveConversion = false;
6467 ToType = To->getType();
6468
6469 InitializationKind Kind =
6470 InitializationKind::CreateCopy(InitLoc: To->getBeginLoc(), EqualLoc: SourceLocation());
6471 // C++11 5.16p3
6472 // The process for determining whether an operand expression E1 of type T1
6473 // can be converted to match an operand expression E2 of type T2 is defined
6474 // as follows:
6475 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
6476 // implicitly converted to type "lvalue reference to T2", subject to the
6477 // constraint that in the conversion the reference must bind directly to
6478 // an lvalue.
6479 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
6480 // implicitly converted to the type "rvalue reference to R2", subject to
6481 // the constraint that the reference must bind directly.
6482 if (To->isGLValue()) {
6483 QualType T = Self.Context.getReferenceQualifiedType(e: To);
6484 InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: T);
6485
6486 InitializationSequence InitSeq(Self, Entity, Kind, From);
6487 if (InitSeq.isDirectReferenceBinding()) {
6488 ToType = T;
6489 HaveConversion = true;
6490 return false;
6491 }
6492
6493 if (InitSeq.isAmbiguous())
6494 return InitSeq.Diagnose(S&: Self, Entity, Kind, Args: From);
6495 }
6496
6497 // -- If E2 is an rvalue, or if the conversion above cannot be done:
6498 // -- if E1 and E2 have class type, and the underlying class types are
6499 // the same or one is a base class of the other:
6500 QualType FTy = From->getType();
6501 QualType TTy = To->getType();
6502 const RecordType *FRec = FTy->getAs<RecordType>();
6503 const RecordType *TRec = TTy->getAs<RecordType>();
6504 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
6505 Self.IsDerivedFrom(Loc: QuestionLoc, Derived: FTy, Base: TTy);
6506 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
6507 Self.IsDerivedFrom(Loc: QuestionLoc, Derived: TTy, Base: FTy))) {
6508 // E1 can be converted to match E2 if the class of T2 is the
6509 // same type as, or a base class of, the class of T1, and
6510 // [cv2 > cv1].
6511 if (FRec == TRec || FDerivedFromT) {
6512 if (TTy.isAtLeastAsQualifiedAs(other: FTy)) {
6513 InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: TTy);
6514 InitializationSequence InitSeq(Self, Entity, Kind, From);
6515 if (InitSeq) {
6516 HaveConversion = true;
6517 return false;
6518 }
6519
6520 if (InitSeq.isAmbiguous())
6521 return InitSeq.Diagnose(S&: Self, Entity, Kind, Args: From);
6522 }
6523 }
6524
6525 return false;
6526 }
6527
6528 // -- Otherwise: E1 can be converted to match E2 if E1 can be
6529 // implicitly converted to the type that expression E2 would have
6530 // if E2 were converted to an rvalue (or the type it has, if E2 is
6531 // an rvalue).
6532 //
6533 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
6534 // to the array-to-pointer or function-to-pointer conversions.
6535 TTy = TTy.getNonLValueExprType(Context: Self.Context);
6536
6537 InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: TTy);
6538 InitializationSequence InitSeq(Self, Entity, Kind, From);
6539 HaveConversion = !InitSeq.Failed();
6540 ToType = TTy;
6541 if (InitSeq.isAmbiguous())
6542 return InitSeq.Diagnose(S&: Self, Entity, Kind, Args: From);
6543
6544 return false;
6545}
6546
6547/// Try to find a common type for two according to C++0x 5.16p5.
6548///
6549/// This is part of the parameter validation for the ? operator. If either
6550/// value operand is a class type, overload resolution is used to find a
6551/// conversion to a common type.
6552static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
6553 SourceLocation QuestionLoc) {
6554 Expr *Args[2] = { LHS.get(), RHS.get() };
6555 OverloadCandidateSet CandidateSet(QuestionLoc,
6556 OverloadCandidateSet::CSK_Operator);
6557 Self.AddBuiltinOperatorCandidates(Op: OO_Conditional, OpLoc: QuestionLoc, Args,
6558 CandidateSet);
6559
6560 OverloadCandidateSet::iterator Best;
6561 switch (CandidateSet.BestViableFunction(S&: Self, Loc: QuestionLoc, Best)) {
6562 case OR_Success: {
6563 // We found a match. Perform the conversions on the arguments and move on.
6564 ExprResult LHSRes = Self.PerformImplicitConversion(
6565 From: LHS.get(), ToType: Best->BuiltinParamTypes[0], ICS: Best->Conversions[0],
6566 Action: Sema::AA_Converting);
6567 if (LHSRes.isInvalid())
6568 break;
6569 LHS = LHSRes;
6570
6571 ExprResult RHSRes = Self.PerformImplicitConversion(
6572 From: RHS.get(), ToType: Best->BuiltinParamTypes[1], ICS: Best->Conversions[1],
6573 Action: Sema::AA_Converting);
6574 if (RHSRes.isInvalid())
6575 break;
6576 RHS = RHSRes;
6577 if (Best->Function)
6578 Self.MarkFunctionReferenced(Loc: QuestionLoc, Func: Best->Function);
6579 return false;
6580 }
6581
6582 case OR_No_Viable_Function:
6583
6584 // Emit a better diagnostic if one of the expressions is a null pointer
6585 // constant and the other is a pointer type. In this case, the user most
6586 // likely forgot to take the address of the other expression.
6587 if (Self.DiagnoseConditionalForNull(LHSExpr: LHS.get(), RHSExpr: RHS.get(), QuestionLoc))
6588 return true;
6589
6590 Self.Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_incompatible_operands)
6591 << LHS.get()->getType() << RHS.get()->getType()
6592 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6593 return true;
6594
6595 case OR_Ambiguous:
6596 Self.Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_ambiguous_ovl)
6597 << LHS.get()->getType() << RHS.get()->getType()
6598 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6599 // FIXME: Print the possible common types by printing the return types of
6600 // the viable candidates.
6601 break;
6602
6603 case OR_Deleted:
6604 llvm_unreachable("Conditional operator has only built-in overloads");
6605 }
6606 return true;
6607}
6608
6609/// Perform an "extended" implicit conversion as returned by
6610/// TryClassUnification.
6611static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
6612 InitializedEntity Entity = InitializedEntity::InitializeTemporary(Type: T);
6613 InitializationKind Kind =
6614 InitializationKind::CreateCopy(InitLoc: E.get()->getBeginLoc(), EqualLoc: SourceLocation());
6615 Expr *Arg = E.get();
6616 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
6617 ExprResult Result = InitSeq.Perform(S&: Self, Entity, Kind, Args: Arg);
6618 if (Result.isInvalid())
6619 return true;
6620
6621 E = Result;
6622 return false;
6623}
6624
6625// Check the condition operand of ?: to see if it is valid for the GCC
6626// extension.
6627static bool isValidVectorForConditionalCondition(ASTContext &Ctx,
6628 QualType CondTy) {
6629 if (!CondTy->isVectorType() && !CondTy->isExtVectorType())
6630 return false;
6631 const QualType EltTy =
6632 cast<VectorType>(Val: CondTy.getCanonicalType())->getElementType();
6633 assert(!EltTy->isEnumeralType() && "Vectors cant be enum types");
6634 return EltTy->isIntegralType(Ctx);
6635}
6636
6637static bool isValidSizelessVectorForConditionalCondition(ASTContext &Ctx,
6638 QualType CondTy) {
6639 if (!CondTy->isSveVLSBuiltinType())
6640 return false;
6641 const QualType EltTy =
6642 cast<BuiltinType>(Val: CondTy.getCanonicalType())->getSveEltType(Ctx);
6643 assert(!EltTy->isEnumeralType() && "Vectors cant be enum types");
6644 return EltTy->isIntegralType(Ctx);
6645}
6646
6647QualType Sema::CheckVectorConditionalTypes(ExprResult &Cond, ExprResult &LHS,
6648 ExprResult &RHS,
6649 SourceLocation QuestionLoc) {
6650 LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
6651 RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
6652
6653 QualType CondType = Cond.get()->getType();
6654 const auto *CondVT = CondType->castAs<VectorType>();
6655 QualType CondElementTy = CondVT->getElementType();
6656 unsigned CondElementCount = CondVT->getNumElements();
6657 QualType LHSType = LHS.get()->getType();
6658 const auto *LHSVT = LHSType->getAs<VectorType>();
6659 QualType RHSType = RHS.get()->getType();
6660 const auto *RHSVT = RHSType->getAs<VectorType>();
6661
6662 QualType ResultType;
6663
6664
6665 if (LHSVT && RHSVT) {
6666 if (isa<ExtVectorType>(Val: CondVT) != isa<ExtVectorType>(Val: LHSVT)) {
6667 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_cond_result_mismatch)
6668 << /*isExtVector*/ isa<ExtVectorType>(Val: CondVT);
6669 return {};
6670 }
6671
6672 // If both are vector types, they must be the same type.
6673 if (!Context.hasSameType(T1: LHSType, T2: RHSType)) {
6674 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_mismatched)
6675 << LHSType << RHSType;
6676 return {};
6677 }
6678 ResultType = Context.getCommonSugaredType(X: LHSType, Y: RHSType);
6679 } else if (LHSVT || RHSVT) {
6680 ResultType = CheckVectorOperands(
6681 LHS, RHS, Loc: QuestionLoc, /*isCompAssign*/ IsCompAssign: false, /*AllowBothBool*/ true,
6682 /*AllowBoolConversions*/ AllowBoolConversion: false,
6683 /*AllowBoolOperation*/ true,
6684 /*ReportInvalid*/ true);
6685 if (ResultType.isNull())
6686 return {};
6687 } else {
6688 // Both are scalar.
6689 LHSType = LHSType.getUnqualifiedType();
6690 RHSType = RHSType.getUnqualifiedType();
6691 QualType ResultElementTy =
6692 Context.hasSameType(T1: LHSType, T2: RHSType)
6693 ? Context.getCommonSugaredType(X: LHSType, Y: RHSType)
6694 : UsualArithmeticConversions(LHS, RHS, Loc: QuestionLoc,
6695 ACK: ACK_Conditional);
6696
6697 if (ResultElementTy->isEnumeralType()) {
6698 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_operand_type)
6699 << ResultElementTy;
6700 return {};
6701 }
6702 if (CondType->isExtVectorType())
6703 ResultType =
6704 Context.getExtVectorType(VectorType: ResultElementTy, NumElts: CondVT->getNumElements());
6705 else
6706 ResultType = Context.getVectorType(
6707 VectorType: ResultElementTy, NumElts: CondVT->getNumElements(), VecKind: VectorKind::Generic);
6708
6709 LHS = ImpCastExprToType(E: LHS.get(), Type: ResultType, CK: CK_VectorSplat);
6710 RHS = ImpCastExprToType(E: RHS.get(), Type: ResultType, CK: CK_VectorSplat);
6711 }
6712
6713 assert(!ResultType.isNull() && ResultType->isVectorType() &&
6714 (!CondType->isExtVectorType() || ResultType->isExtVectorType()) &&
6715 "Result should have been a vector type");
6716 auto *ResultVectorTy = ResultType->castAs<VectorType>();
6717 QualType ResultElementTy = ResultVectorTy->getElementType();
6718 unsigned ResultElementCount = ResultVectorTy->getNumElements();
6719
6720 if (ResultElementCount != CondElementCount) {
6721 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_size) << CondType
6722 << ResultType;
6723 return {};
6724 }
6725
6726 if (Context.getTypeSize(T: ResultElementTy) !=
6727 Context.getTypeSize(T: CondElementTy)) {
6728 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_element_size) << CondType
6729 << ResultType;
6730 return {};
6731 }
6732
6733 return ResultType;
6734}
6735
6736QualType Sema::CheckSizelessVectorConditionalTypes(ExprResult &Cond,
6737 ExprResult &LHS,
6738 ExprResult &RHS,
6739 SourceLocation QuestionLoc) {
6740 LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
6741 RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
6742
6743 QualType CondType = Cond.get()->getType();
6744 const auto *CondBT = CondType->castAs<BuiltinType>();
6745 QualType CondElementTy = CondBT->getSveEltType(Ctx: Context);
6746 llvm::ElementCount CondElementCount =
6747 Context.getBuiltinVectorTypeInfo(VecTy: CondBT).EC;
6748
6749 QualType LHSType = LHS.get()->getType();
6750 const auto *LHSBT =
6751 LHSType->isSveVLSBuiltinType() ? LHSType->getAs<BuiltinType>() : nullptr;
6752 QualType RHSType = RHS.get()->getType();
6753 const auto *RHSBT =
6754 RHSType->isSveVLSBuiltinType() ? RHSType->getAs<BuiltinType>() : nullptr;
6755
6756 QualType ResultType;
6757
6758 if (LHSBT && RHSBT) {
6759 // If both are sizeless vector types, they must be the same type.
6760 if (!Context.hasSameType(T1: LHSType, T2: RHSType)) {
6761 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_mismatched)
6762 << LHSType << RHSType;
6763 return QualType();
6764 }
6765 ResultType = LHSType;
6766 } else if (LHSBT || RHSBT) {
6767 ResultType = CheckSizelessVectorOperands(
6768 LHS, RHS, Loc: QuestionLoc, /*IsCompAssign*/ false, OperationKind: ACK_Conditional);
6769 if (ResultType.isNull())
6770 return QualType();
6771 } else {
6772 // Both are scalar so splat
6773 QualType ResultElementTy;
6774 LHSType = LHSType.getCanonicalType().getUnqualifiedType();
6775 RHSType = RHSType.getCanonicalType().getUnqualifiedType();
6776
6777 if (Context.hasSameType(T1: LHSType, T2: RHSType))
6778 ResultElementTy = LHSType;
6779 else
6780 ResultElementTy =
6781 UsualArithmeticConversions(LHS, RHS, Loc: QuestionLoc, ACK: ACK_Conditional);
6782
6783 if (ResultElementTy->isEnumeralType()) {
6784 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_operand_type)
6785 << ResultElementTy;
6786 return QualType();
6787 }
6788
6789 ResultType = Context.getScalableVectorType(
6790 EltTy: ResultElementTy, NumElts: CondElementCount.getKnownMinValue());
6791
6792 LHS = ImpCastExprToType(E: LHS.get(), Type: ResultType, CK: CK_VectorSplat);
6793 RHS = ImpCastExprToType(E: RHS.get(), Type: ResultType, CK: CK_VectorSplat);
6794 }
6795
6796 assert(!ResultType.isNull() && ResultType->isSveVLSBuiltinType() &&
6797 "Result should have been a vector type");
6798 auto *ResultBuiltinTy = ResultType->castAs<BuiltinType>();
6799 QualType ResultElementTy = ResultBuiltinTy->getSveEltType(Ctx: Context);
6800 llvm::ElementCount ResultElementCount =
6801 Context.getBuiltinVectorTypeInfo(VecTy: ResultBuiltinTy).EC;
6802
6803 if (ResultElementCount != CondElementCount) {
6804 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_size)
6805 << CondType << ResultType;
6806 return QualType();
6807 }
6808
6809 if (Context.getTypeSize(T: ResultElementTy) !=
6810 Context.getTypeSize(T: CondElementTy)) {
6811 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_vector_element_size)
6812 << CondType << ResultType;
6813 return QualType();
6814 }
6815
6816 return ResultType;
6817}
6818
6819QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
6820 ExprResult &RHS, ExprValueKind &VK,
6821 ExprObjectKind &OK,
6822 SourceLocation QuestionLoc) {
6823 // FIXME: Handle C99's complex types, block pointers and Obj-C++ interface
6824 // pointers.
6825
6826 // Assume r-value.
6827 VK = VK_PRValue;
6828 OK = OK_Ordinary;
6829 bool IsVectorConditional =
6830 isValidVectorForConditionalCondition(Ctx&: Context, CondTy: Cond.get()->getType());
6831
6832 bool IsSizelessVectorConditional =
6833 isValidSizelessVectorForConditionalCondition(Ctx&: Context,
6834 CondTy: Cond.get()->getType());
6835
6836 // C++11 [expr.cond]p1
6837 // The first expression is contextually converted to bool.
6838 if (!Cond.get()->isTypeDependent()) {
6839 ExprResult CondRes = IsVectorConditional || IsSizelessVectorConditional
6840 ? DefaultFunctionArrayLvalueConversion(E: Cond.get())
6841 : CheckCXXBooleanCondition(CondExpr: Cond.get());
6842 if (CondRes.isInvalid())
6843 return QualType();
6844 Cond = CondRes;
6845 } else {
6846 // To implement C++, the first expression typically doesn't alter the result
6847 // type of the conditional, however the GCC compatible vector extension
6848 // changes the result type to be that of the conditional. Since we cannot
6849 // know if this is a vector extension here, delay the conversion of the
6850 // LHS/RHS below until later.
6851 return Context.DependentTy;
6852 }
6853
6854
6855 // Either of the arguments dependent?
6856 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
6857 return Context.DependentTy;
6858
6859 // C++11 [expr.cond]p2
6860 // If either the second or the third operand has type (cv) void, ...
6861 QualType LTy = LHS.get()->getType();
6862 QualType RTy = RHS.get()->getType();
6863 bool LVoid = LTy->isVoidType();
6864 bool RVoid = RTy->isVoidType();
6865 if (LVoid || RVoid) {
6866 // ... one of the following shall hold:
6867 // -- The second or the third operand (but not both) is a (possibly
6868 // parenthesized) throw-expression; the result is of the type
6869 // and value category of the other.
6870 bool LThrow = isa<CXXThrowExpr>(Val: LHS.get()->IgnoreParenImpCasts());
6871 bool RThrow = isa<CXXThrowExpr>(Val: RHS.get()->IgnoreParenImpCasts());
6872
6873 // Void expressions aren't legal in the vector-conditional expressions.
6874 if (IsVectorConditional) {
6875 SourceRange DiagLoc =
6876 LVoid ? LHS.get()->getSourceRange() : RHS.get()->getSourceRange();
6877 bool IsThrow = LVoid ? LThrow : RThrow;
6878 Diag(Loc: DiagLoc.getBegin(), DiagID: diag::err_conditional_vector_has_void)
6879 << DiagLoc << IsThrow;
6880 return QualType();
6881 }
6882
6883 if (LThrow != RThrow) {
6884 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
6885 VK = NonThrow->getValueKind();
6886 // DR (no number yet): the result is a bit-field if the
6887 // non-throw-expression operand is a bit-field.
6888 OK = NonThrow->getObjectKind();
6889 return NonThrow->getType();
6890 }
6891
6892 // -- Both the second and third operands have type void; the result is of
6893 // type void and is a prvalue.
6894 if (LVoid && RVoid)
6895 return Context.getCommonSugaredType(X: LTy, Y: RTy);
6896
6897 // Neither holds, error.
6898 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_void_nonvoid)
6899 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
6900 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6901 return QualType();
6902 }
6903
6904 // Neither is void.
6905 if (IsVectorConditional)
6906 return CheckVectorConditionalTypes(Cond, LHS, RHS, QuestionLoc);
6907
6908 if (IsSizelessVectorConditional)
6909 return CheckSizelessVectorConditionalTypes(Cond, LHS, RHS, QuestionLoc);
6910
6911 // WebAssembly tables are not allowed as conditional LHS or RHS.
6912 if (LTy->isWebAssemblyTableType() || RTy->isWebAssemblyTableType()) {
6913 Diag(Loc: QuestionLoc, DiagID: diag::err_wasm_table_conditional_expression)
6914 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6915 return QualType();
6916 }
6917
6918 // C++11 [expr.cond]p3
6919 // Otherwise, if the second and third operand have different types, and
6920 // either has (cv) class type [...] an attempt is made to convert each of
6921 // those operands to the type of the other.
6922 if (!Context.hasSameType(T1: LTy, T2: RTy) &&
6923 (LTy->isRecordType() || RTy->isRecordType())) {
6924 // These return true if a single direction is already ambiguous.
6925 QualType L2RType, R2LType;
6926 bool HaveL2R, HaveR2L;
6927 if (TryClassUnification(Self&: *this, From: LHS.get(), To: RHS.get(), QuestionLoc, HaveConversion&: HaveL2R, ToType&: L2RType))
6928 return QualType();
6929 if (TryClassUnification(Self&: *this, From: RHS.get(), To: LHS.get(), QuestionLoc, HaveConversion&: HaveR2L, ToType&: R2LType))
6930 return QualType();
6931
6932 // If both can be converted, [...] the program is ill-formed.
6933 if (HaveL2R && HaveR2L) {
6934 Diag(Loc: QuestionLoc, DiagID: diag::err_conditional_ambiguous)
6935 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
6936 return QualType();
6937 }
6938
6939 // If exactly one conversion is possible, that conversion is applied to
6940 // the chosen operand and the converted operands are used in place of the
6941 // original operands for the remainder of this section.
6942 if (HaveL2R) {
6943 if (ConvertForConditional(Self&: *this, E&: LHS, T: L2RType) || LHS.isInvalid())
6944 return QualType();
6945 LTy = LHS.get()->getType();
6946 } else if (HaveR2L) {
6947 if (ConvertForConditional(Self&: *this, E&: RHS, T: R2LType) || RHS.isInvalid())
6948 return QualType();
6949 RTy = RHS.get()->getType();
6950 }
6951 }
6952
6953 // C++11 [expr.cond]p3
6954 // if both are glvalues of the same value category and the same type except
6955 // for cv-qualification, an attempt is made to convert each of those
6956 // operands to the type of the other.
6957 // FIXME:
6958 // Resolving a defect in P0012R1: we extend this to cover all cases where
6959 // one of the operands is reference-compatible with the other, in order
6960 // to support conditionals between functions differing in noexcept. This
6961 // will similarly cover difference in array bounds after P0388R4.
6962 // FIXME: If LTy and RTy have a composite pointer type, should we convert to
6963 // that instead?
6964 ExprValueKind LVK = LHS.get()->getValueKind();
6965 ExprValueKind RVK = RHS.get()->getValueKind();
6966 if (!Context.hasSameType(T1: LTy, T2: RTy) && LVK == RVK && LVK != VK_PRValue) {
6967 // DerivedToBase was already handled by the class-specific case above.
6968 // FIXME: Should we allow ObjC conversions here?
6969 const ReferenceConversions AllowedConversions =
6970 ReferenceConversions::Qualification |
6971 ReferenceConversions::NestedQualification |
6972 ReferenceConversions::Function;
6973
6974 ReferenceConversions RefConv;
6975 if (CompareReferenceRelationship(Loc: QuestionLoc, T1: LTy, T2: RTy, Conv: &RefConv) ==
6976 Ref_Compatible &&
6977 !(RefConv & ~AllowedConversions) &&
6978 // [...] subject to the constraint that the reference must bind
6979 // directly [...]
6980 !RHS.get()->refersToBitField() && !RHS.get()->refersToVectorElement()) {
6981 RHS = ImpCastExprToType(E: RHS.get(), Type: LTy, CK: CK_NoOp, VK: RVK);
6982 RTy = RHS.get()->getType();
6983 } else if (CompareReferenceRelationship(Loc: QuestionLoc, T1: RTy, T2: LTy, Conv: &RefConv) ==
6984 Ref_Compatible &&
6985 !(RefConv & ~AllowedConversions) &&
6986 !LHS.get()->refersToBitField() &&
6987 !LHS.get()->refersToVectorElement()) {
6988 LHS = ImpCastExprToType(E: LHS.get(), Type: RTy, CK: CK_NoOp, VK: LVK);
6989 LTy = LHS.get()->getType();
6990 }
6991 }
6992
6993 // C++11 [expr.cond]p4
6994 // If the second and third operands are glvalues of the same value
6995 // category and have the same type, the result is of that type and
6996 // value category and it is a bit-field if the second or the third
6997 // operand is a bit-field, or if both are bit-fields.
6998 // We only extend this to bitfields, not to the crazy other kinds of
6999 // l-values.
7000 bool Same = Context.hasSameType(T1: LTy, T2: RTy);
7001 if (Same && LVK == RVK && LVK != VK_PRValue &&
7002 LHS.get()->isOrdinaryOrBitFieldObject() &&
7003 RHS.get()->isOrdinaryOrBitFieldObject()) {
7004 VK = LHS.get()->getValueKind();
7005 if (LHS.get()->getObjectKind() == OK_BitField ||
7006 RHS.get()->getObjectKind() == OK_BitField)
7007 OK = OK_BitField;
7008 return Context.getCommonSugaredType(X: LTy, Y: RTy);
7009 }
7010
7011 // C++11 [expr.cond]p5
7012 // Otherwise, the result is a prvalue. If the second and third operands
7013 // do not have the same type, and either has (cv) class type, ...
7014 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
7015 // ... overload resolution is used to determine the conversions (if any)
7016 // to be applied to the operands. If the overload resolution fails, the
7017 // program is ill-formed.
7018 if (FindConditionalOverload(Self&: *this, LHS, RHS, QuestionLoc))
7019 return QualType();
7020 }
7021
7022 // C++11 [expr.cond]p6
7023 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
7024 // conversions are performed on the second and third operands.
7025 LHS = DefaultFunctionArrayLvalueConversion(E: LHS.get());
7026 RHS = DefaultFunctionArrayLvalueConversion(E: RHS.get());
7027 if (LHS.isInvalid() || RHS.isInvalid())
7028 return QualType();
7029 LTy = LHS.get()->getType();
7030 RTy = RHS.get()->getType();
7031
7032 // After those conversions, one of the following shall hold:
7033 // -- The second and third operands have the same type; the result
7034 // is of that type. If the operands have class type, the result
7035 // is a prvalue temporary of the result type, which is
7036 // copy-initialized from either the second operand or the third
7037 // operand depending on the value of the first operand.
7038 if (Context.hasSameType(T1: LTy, T2: RTy)) {
7039 if (LTy->isRecordType()) {
7040 // The operands have class type. Make a temporary copy.
7041 ExprResult LHSCopy = PerformCopyInitialization(
7042 Entity: InitializedEntity::InitializeTemporary(Type: LTy), EqualLoc: SourceLocation(), Init: LHS);
7043 if (LHSCopy.isInvalid())
7044 return QualType();
7045
7046 ExprResult RHSCopy = PerformCopyInitialization(
7047 Entity: InitializedEntity::InitializeTemporary(Type: RTy), EqualLoc: SourceLocation(), Init: RHS);
7048 if (RHSCopy.isInvalid())
7049 return QualType();
7050
7051 LHS = LHSCopy;
7052 RHS = RHSCopy;
7053 }
7054 return Context.getCommonSugaredType(X: LTy, Y: RTy);
7055 }
7056
7057 // Extension: conditional operator involving vector types.
7058 if (LTy->isVectorType() || RTy->isVectorType())
7059 return CheckVectorOperands(LHS, RHS, Loc: QuestionLoc, /*isCompAssign*/ IsCompAssign: false,
7060 /*AllowBothBool*/ true,
7061 /*AllowBoolConversions*/ AllowBoolConversion: false,
7062 /*AllowBoolOperation*/ false,
7063 /*ReportInvalid*/ true);
7064
7065 // -- The second and third operands have arithmetic or enumeration type;
7066 // the usual arithmetic conversions are performed to bring them to a
7067 // common type, and the result is of that type.
7068 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
7069 QualType ResTy =
7070 UsualArithmeticConversions(LHS, RHS, Loc: QuestionLoc, ACK: ACK_Conditional);
7071 if (LHS.isInvalid() || RHS.isInvalid())
7072 return QualType();
7073 if (ResTy.isNull()) {
7074 Diag(Loc: QuestionLoc,
7075 DiagID: diag::err_typecheck_cond_incompatible_operands) << LTy << RTy
7076 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7077 return QualType();
7078 }
7079
7080 LHS = ImpCastExprToType(E: LHS.get(), Type: ResTy, CK: PrepareScalarCast(src&: LHS, destType: ResTy));
7081 RHS = ImpCastExprToType(E: RHS.get(), Type: ResTy, CK: PrepareScalarCast(src&: RHS, destType: ResTy));
7082
7083 return ResTy;
7084 }
7085
7086 // -- The second and third operands have pointer type, or one has pointer
7087 // type and the other is a null pointer constant, or both are null
7088 // pointer constants, at least one of which is non-integral; pointer
7089 // conversions and qualification conversions are performed to bring them
7090 // to their composite pointer type. The result is of the composite
7091 // pointer type.
7092 // -- The second and third operands have pointer to member type, or one has
7093 // pointer to member type and the other is a null pointer constant;
7094 // pointer to member conversions and qualification conversions are
7095 // performed to bring them to a common type, whose cv-qualification
7096 // shall match the cv-qualification of either the second or the third
7097 // operand. The result is of the common type.
7098 QualType Composite = FindCompositePointerType(Loc: QuestionLoc, E1&: LHS, E2&: RHS);
7099 if (!Composite.isNull())
7100 return Composite;
7101
7102 // Similarly, attempt to find composite type of two objective-c pointers.
7103 Composite = ObjC().FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
7104 if (LHS.isInvalid() || RHS.isInvalid())
7105 return QualType();
7106 if (!Composite.isNull())
7107 return Composite;
7108
7109 // Check if we are using a null with a non-pointer type.
7110 if (DiagnoseConditionalForNull(LHSExpr: LHS.get(), RHSExpr: RHS.get(), QuestionLoc))
7111 return QualType();
7112
7113 Diag(Loc: QuestionLoc, DiagID: diag::err_typecheck_cond_incompatible_operands)
7114 << LHS.get()->getType() << RHS.get()->getType()
7115 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7116 return QualType();
7117}
7118
7119QualType Sema::FindCompositePointerType(SourceLocation Loc,
7120 Expr *&E1, Expr *&E2,
7121 bool ConvertArgs) {
7122 assert(getLangOpts().CPlusPlus && "This function assumes C++");
7123
7124 // C++1z [expr]p14:
7125 // The composite pointer type of two operands p1 and p2 having types T1
7126 // and T2
7127 QualType T1 = E1->getType(), T2 = E2->getType();
7128
7129 // where at least one is a pointer or pointer to member type or
7130 // std::nullptr_t is:
7131 bool T1IsPointerLike = T1->isAnyPointerType() || T1->isMemberPointerType() ||
7132 T1->isNullPtrType();
7133 bool T2IsPointerLike = T2->isAnyPointerType() || T2->isMemberPointerType() ||
7134 T2->isNullPtrType();
7135 if (!T1IsPointerLike && !T2IsPointerLike)
7136 return QualType();
7137
7138 // - if both p1 and p2 are null pointer constants, std::nullptr_t;
7139 // This can't actually happen, following the standard, but we also use this
7140 // to implement the end of [expr.conv], which hits this case.
7141 //
7142 // - if either p1 or p2 is a null pointer constant, T2 or T1, respectively;
7143 if (T1IsPointerLike &&
7144 E2->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull)) {
7145 if (ConvertArgs)
7146 E2 = ImpCastExprToType(E: E2, Type: T1, CK: T1->isMemberPointerType()
7147 ? CK_NullToMemberPointer
7148 : CK_NullToPointer).get();
7149 return T1;
7150 }
7151 if (T2IsPointerLike &&
7152 E1->isNullPointerConstant(Ctx&: Context, NPC: Expr::NPC_ValueDependentIsNull)) {
7153 if (ConvertArgs)
7154 E1 = ImpCastExprToType(E: E1, Type: T2, CK: T2->isMemberPointerType()
7155 ? CK_NullToMemberPointer
7156 : CK_NullToPointer).get();
7157 return T2;
7158 }
7159
7160 // Now both have to be pointers or member pointers.
7161 if (!T1IsPointerLike || !T2IsPointerLike)
7162 return QualType();
7163 assert(!T1->isNullPtrType() && !T2->isNullPtrType() &&
7164 "nullptr_t should be a null pointer constant");
7165
7166 struct Step {
7167 enum Kind { Pointer, ObjCPointer, MemberPointer, Array } K;
7168 // Qualifiers to apply under the step kind.
7169 Qualifiers Quals;
7170 /// The class for a pointer-to-member; a constant array type with a bound
7171 /// (if any) for an array.
7172 const Type *ClassOrBound;
7173
7174 Step(Kind K, const Type *ClassOrBound = nullptr)
7175 : K(K), ClassOrBound(ClassOrBound) {}
7176 QualType rebuild(ASTContext &Ctx, QualType T) const {
7177 T = Ctx.getQualifiedType(T, Qs: Quals);
7178 switch (K) {
7179 case Pointer:
7180 return Ctx.getPointerType(T);
7181 case MemberPointer:
7182 return Ctx.getMemberPointerType(T, Cls: ClassOrBound);
7183 case ObjCPointer:
7184 return Ctx.getObjCObjectPointerType(OIT: T);
7185 case Array:
7186 if (auto *CAT = cast_or_null<ConstantArrayType>(Val: ClassOrBound))
7187 return Ctx.getConstantArrayType(EltTy: T, ArySize: CAT->getSize(), SizeExpr: nullptr,
7188 ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
7189 else
7190 return Ctx.getIncompleteArrayType(EltTy: T, ASM: ArraySizeModifier::Normal, IndexTypeQuals: 0);
7191 }
7192 llvm_unreachable("unknown step kind");
7193 }
7194 };
7195
7196 SmallVector<Step, 8> Steps;
7197
7198 // - if T1 is "pointer to cv1 C1" and T2 is "pointer to cv2 C2", where C1
7199 // is reference-related to C2 or C2 is reference-related to C1 (8.6.3),
7200 // the cv-combined type of T1 and T2 or the cv-combined type of T2 and T1,
7201 // respectively;
7202 // - if T1 is "pointer to member of C1 of type cv1 U1" and T2 is "pointer
7203 // to member of C2 of type cv2 U2" for some non-function type U, where
7204 // C1 is reference-related to C2 or C2 is reference-related to C1, the
7205 // cv-combined type of T2 and T1 or the cv-combined type of T1 and T2,
7206 // respectively;
7207 // - if T1 and T2 are similar types (4.5), the cv-combined type of T1 and
7208 // T2;
7209 //
7210 // Dismantle T1 and T2 to simultaneously determine whether they are similar
7211 // and to prepare to form the cv-combined type if so.
7212 QualType Composite1 = T1;
7213 QualType Composite2 = T2;
7214 unsigned NeedConstBefore = 0;
7215 while (true) {
7216 assert(!Composite1.isNull() && !Composite2.isNull());
7217
7218 Qualifiers Q1, Q2;
7219 Composite1 = Context.getUnqualifiedArrayType(T: Composite1, Quals&: Q1);
7220 Composite2 = Context.getUnqualifiedArrayType(T: Composite2, Quals&: Q2);
7221
7222 // Top-level qualifiers are ignored. Merge at all lower levels.
7223 if (!Steps.empty()) {
7224 // Find the qualifier union: (approximately) the unique minimal set of
7225 // qualifiers that is compatible with both types.
7226 Qualifiers Quals = Qualifiers::fromCVRUMask(CVRU: Q1.getCVRUQualifiers() |
7227 Q2.getCVRUQualifiers());
7228
7229 // Under one level of pointer or pointer-to-member, we can change to an
7230 // unambiguous compatible address space.
7231 if (Q1.getAddressSpace() == Q2.getAddressSpace()) {
7232 Quals.setAddressSpace(Q1.getAddressSpace());
7233 } else if (Steps.size() == 1) {
7234 bool MaybeQ1 = Q1.isAddressSpaceSupersetOf(other: Q2);
7235 bool MaybeQ2 = Q2.isAddressSpaceSupersetOf(other: Q1);
7236 if (MaybeQ1 == MaybeQ2) {
7237 // Exception for ptr size address spaces. Should be able to choose
7238 // either address space during comparison.
7239 if (isPtrSizeAddressSpace(AS: Q1.getAddressSpace()) ||
7240 isPtrSizeAddressSpace(AS: Q2.getAddressSpace()))
7241 MaybeQ1 = true;
7242 else
7243 return QualType(); // No unique best address space.
7244 }
7245 Quals.setAddressSpace(MaybeQ1 ? Q1.getAddressSpace()
7246 : Q2.getAddressSpace());
7247 } else {
7248 return QualType();
7249 }
7250
7251 // FIXME: In C, we merge __strong and none to __strong at the top level.
7252 if (Q1.getObjCGCAttr() == Q2.getObjCGCAttr())
7253 Quals.setObjCGCAttr(Q1.getObjCGCAttr());
7254 else if (T1->isVoidPointerType() || T2->isVoidPointerType())
7255 assert(Steps.size() == 1);
7256 else
7257 return QualType();
7258
7259 // Mismatched lifetime qualifiers never compatibly include each other.
7260 if (Q1.getObjCLifetime() == Q2.getObjCLifetime())
7261 Quals.setObjCLifetime(Q1.getObjCLifetime());
7262 else if (T1->isVoidPointerType() || T2->isVoidPointerType())
7263 assert(Steps.size() == 1);
7264 else
7265 return QualType();
7266
7267 Steps.back().Quals = Quals;
7268 if (Q1 != Quals || Q2 != Quals)
7269 NeedConstBefore = Steps.size() - 1;
7270 }
7271
7272 // FIXME: Can we unify the following with UnwrapSimilarTypes?
7273
7274 const ArrayType *Arr1, *Arr2;
7275 if ((Arr1 = Context.getAsArrayType(T: Composite1)) &&
7276 (Arr2 = Context.getAsArrayType(T: Composite2))) {
7277 auto *CAT1 = dyn_cast<ConstantArrayType>(Val: Arr1);
7278 auto *CAT2 = dyn_cast<ConstantArrayType>(Val: Arr2);
7279 if (CAT1 && CAT2 && CAT1->getSize() == CAT2->getSize()) {
7280 Composite1 = Arr1->getElementType();
7281 Composite2 = Arr2->getElementType();
7282 Steps.emplace_back(Args: Step::Array, Args&: CAT1);
7283 continue;
7284 }
7285 bool IAT1 = isa<IncompleteArrayType>(Val: Arr1);
7286 bool IAT2 = isa<IncompleteArrayType>(Val: Arr2);
7287 if ((IAT1 && IAT2) ||
7288 (getLangOpts().CPlusPlus20 && (IAT1 != IAT2) &&
7289 ((bool)CAT1 != (bool)CAT2) &&
7290 (Steps.empty() || Steps.back().K != Step::Array))) {
7291 // In C++20 onwards, we can unify an array of N T with an array of
7292 // a different or unknown bound. But we can't form an array whose
7293 // element type is an array of unknown bound by doing so.
7294 Composite1 = Arr1->getElementType();
7295 Composite2 = Arr2->getElementType();
7296 Steps.emplace_back(Args: Step::Array);
7297 if (CAT1 || CAT2)
7298 NeedConstBefore = Steps.size();
7299 continue;
7300 }
7301 }
7302
7303 const PointerType *Ptr1, *Ptr2;
7304 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
7305 (Ptr2 = Composite2->getAs<PointerType>())) {
7306 Composite1 = Ptr1->getPointeeType();
7307 Composite2 = Ptr2->getPointeeType();
7308 Steps.emplace_back(Args: Step::Pointer);
7309 continue;
7310 }
7311
7312 const ObjCObjectPointerType *ObjPtr1, *ObjPtr2;
7313 if ((ObjPtr1 = Composite1->getAs<ObjCObjectPointerType>()) &&
7314 (ObjPtr2 = Composite2->getAs<ObjCObjectPointerType>())) {
7315 Composite1 = ObjPtr1->getPointeeType();
7316 Composite2 = ObjPtr2->getPointeeType();
7317 Steps.emplace_back(Args: Step::ObjCPointer);
7318 continue;
7319 }
7320
7321 const MemberPointerType *MemPtr1, *MemPtr2;
7322 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
7323 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
7324 Composite1 = MemPtr1->getPointeeType();
7325 Composite2 = MemPtr2->getPointeeType();
7326
7327 // At the top level, we can perform a base-to-derived pointer-to-member
7328 // conversion:
7329 //
7330 // - [...] where C1 is reference-related to C2 or C2 is
7331 // reference-related to C1
7332 //
7333 // (Note that the only kinds of reference-relatedness in scope here are
7334 // "same type or derived from".) At any other level, the class must
7335 // exactly match.
7336 const Type *Class = nullptr;
7337 QualType Cls1(MemPtr1->getClass(), 0);
7338 QualType Cls2(MemPtr2->getClass(), 0);
7339 if (Context.hasSameType(T1: Cls1, T2: Cls2))
7340 Class = MemPtr1->getClass();
7341 else if (Steps.empty())
7342 Class = IsDerivedFrom(Loc, Derived: Cls1, Base: Cls2) ? MemPtr1->getClass() :
7343 IsDerivedFrom(Loc, Derived: Cls2, Base: Cls1) ? MemPtr2->getClass() : nullptr;
7344 if (!Class)
7345 return QualType();
7346
7347 Steps.emplace_back(Args: Step::MemberPointer, Args&: Class);
7348 continue;
7349 }
7350
7351 // Special case: at the top level, we can decompose an Objective-C pointer
7352 // and a 'cv void *'. Unify the qualifiers.
7353 if (Steps.empty() && ((Composite1->isVoidPointerType() &&
7354 Composite2->isObjCObjectPointerType()) ||
7355 (Composite1->isObjCObjectPointerType() &&
7356 Composite2->isVoidPointerType()))) {
7357 Composite1 = Composite1->getPointeeType();
7358 Composite2 = Composite2->getPointeeType();
7359 Steps.emplace_back(Args: Step::Pointer);
7360 continue;
7361 }
7362
7363 // FIXME: block pointer types?
7364
7365 // Cannot unwrap any more types.
7366 break;
7367 }
7368
7369 // - if T1 or T2 is "pointer to noexcept function" and the other type is
7370 // "pointer to function", where the function types are otherwise the same,
7371 // "pointer to function";
7372 // - if T1 or T2 is "pointer to member of C1 of type function", the other
7373 // type is "pointer to member of C2 of type noexcept function", and C1
7374 // is reference-related to C2 or C2 is reference-related to C1, where
7375 // the function types are otherwise the same, "pointer to member of C2 of
7376 // type function" or "pointer to member of C1 of type function",
7377 // respectively;
7378 //
7379 // We also support 'noreturn' here, so as a Clang extension we generalize the
7380 // above to:
7381 //
7382 // - [Clang] If T1 and T2 are both of type "pointer to function" or
7383 // "pointer to member function" and the pointee types can be unified
7384 // by a function pointer conversion, that conversion is applied
7385 // before checking the following rules.
7386 //
7387 // We've already unwrapped down to the function types, and we want to merge
7388 // rather than just convert, so do this ourselves rather than calling
7389 // IsFunctionConversion.
7390 //
7391 // FIXME: In order to match the standard wording as closely as possible, we
7392 // currently only do this under a single level of pointers. Ideally, we would
7393 // allow this in general, and set NeedConstBefore to the relevant depth on
7394 // the side(s) where we changed anything. If we permit that, we should also
7395 // consider this conversion when determining type similarity and model it as
7396 // a qualification conversion.
7397 if (Steps.size() == 1) {
7398 if (auto *FPT1 = Composite1->getAs<FunctionProtoType>()) {
7399 if (auto *FPT2 = Composite2->getAs<FunctionProtoType>()) {
7400 FunctionProtoType::ExtProtoInfo EPI1 = FPT1->getExtProtoInfo();
7401 FunctionProtoType::ExtProtoInfo EPI2 = FPT2->getExtProtoInfo();
7402
7403 // The result is noreturn if both operands are.
7404 bool Noreturn =
7405 EPI1.ExtInfo.getNoReturn() && EPI2.ExtInfo.getNoReturn();
7406 EPI1.ExtInfo = EPI1.ExtInfo.withNoReturn(noReturn: Noreturn);
7407 EPI2.ExtInfo = EPI2.ExtInfo.withNoReturn(noReturn: Noreturn);
7408
7409 // The result is nothrow if both operands are.
7410 SmallVector<QualType, 8> ExceptionTypeStorage;
7411 EPI1.ExceptionSpec = EPI2.ExceptionSpec = Context.mergeExceptionSpecs(
7412 ESI1: EPI1.ExceptionSpec, ESI2: EPI2.ExceptionSpec, ExceptionTypeStorage,
7413 AcceptDependent: getLangOpts().CPlusPlus17);
7414
7415 Composite1 = Context.getFunctionType(ResultTy: FPT1->getReturnType(),
7416 Args: FPT1->getParamTypes(), EPI: EPI1);
7417 Composite2 = Context.getFunctionType(ResultTy: FPT2->getReturnType(),
7418 Args: FPT2->getParamTypes(), EPI: EPI2);
7419 }
7420 }
7421 }
7422
7423 // There are some more conversions we can perform under exactly one pointer.
7424 if (Steps.size() == 1 && Steps.front().K == Step::Pointer &&
7425 !Context.hasSameType(T1: Composite1, T2: Composite2)) {
7426 // - if T1 or T2 is "pointer to cv1 void" and the other type is
7427 // "pointer to cv2 T", where T is an object type or void,
7428 // "pointer to cv12 void", where cv12 is the union of cv1 and cv2;
7429 if (Composite1->isVoidType() && Composite2->isObjectType())
7430 Composite2 = Composite1;
7431 else if (Composite2->isVoidType() && Composite1->isObjectType())
7432 Composite1 = Composite2;
7433 // - if T1 is "pointer to cv1 C1" and T2 is "pointer to cv2 C2", where C1
7434 // is reference-related to C2 or C2 is reference-related to C1 (8.6.3),
7435 // the cv-combined type of T1 and T2 or the cv-combined type of T2 and
7436 // T1, respectively;
7437 //
7438 // The "similar type" handling covers all of this except for the "T1 is a
7439 // base class of T2" case in the definition of reference-related.
7440 else if (IsDerivedFrom(Loc, Derived: Composite1, Base: Composite2))
7441 Composite1 = Composite2;
7442 else if (IsDerivedFrom(Loc, Derived: Composite2, Base: Composite1))
7443 Composite2 = Composite1;
7444 }
7445
7446 // At this point, either the inner types are the same or we have failed to
7447 // find a composite pointer type.
7448 if (!Context.hasSameType(T1: Composite1, T2: Composite2))
7449 return QualType();
7450
7451 // Per C++ [conv.qual]p3, add 'const' to every level before the last
7452 // differing qualifier.
7453 for (unsigned I = 0; I != NeedConstBefore; ++I)
7454 Steps[I].Quals.addConst();
7455
7456 // Rebuild the composite type.
7457 QualType Composite = Context.getCommonSugaredType(X: Composite1, Y: Composite2);
7458 for (auto &S : llvm::reverse(C&: Steps))
7459 Composite = S.rebuild(Ctx&: Context, T: Composite);
7460
7461 if (ConvertArgs) {
7462 // Convert the expressions to the composite pointer type.
7463 InitializedEntity Entity =
7464 InitializedEntity::InitializeTemporary(Type: Composite);
7465 InitializationKind Kind =
7466 InitializationKind::CreateCopy(InitLoc: Loc, EqualLoc: SourceLocation());
7467
7468 InitializationSequence E1ToC(*this, Entity, Kind, E1);
7469 if (!E1ToC)
7470 return QualType();
7471
7472 InitializationSequence E2ToC(*this, Entity, Kind, E2);
7473 if (!E2ToC)
7474 return QualType();
7475
7476 // FIXME: Let the caller know if these fail to avoid duplicate diagnostics.
7477 ExprResult E1Result = E1ToC.Perform(S&: *this, Entity, Kind, Args: E1);
7478 if (E1Result.isInvalid())
7479 return QualType();
7480 E1 = E1Result.get();
7481
7482 ExprResult E2Result = E2ToC.Perform(S&: *this, Entity, Kind, Args: E2);
7483 if (E2Result.isInvalid())
7484 return QualType();
7485 E2 = E2Result.get();
7486 }
7487
7488 return Composite;
7489}
7490
7491ExprResult Sema::MaybeBindToTemporary(Expr *E) {
7492 if (!E)
7493 return ExprError();
7494
7495 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
7496
7497 // If the result is a glvalue, we shouldn't bind it.
7498 if (E->isGLValue())
7499 return E;
7500
7501 // In ARC, calls that return a retainable type can return retained,
7502 // in which case we have to insert a consuming cast.
7503 if (getLangOpts().ObjCAutoRefCount &&
7504 E->getType()->isObjCRetainableType()) {
7505
7506 bool ReturnsRetained;
7507
7508 // For actual calls, we compute this by examining the type of the
7509 // called value.
7510 if (CallExpr *Call = dyn_cast<CallExpr>(Val: E)) {
7511 Expr *Callee = Call->getCallee()->IgnoreParens();
7512 QualType T = Callee->getType();
7513
7514 if (T == Context.BoundMemberTy) {
7515 // Handle pointer-to-members.
7516 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Val: Callee))
7517 T = BinOp->getRHS()->getType();
7518 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Val: Callee))
7519 T = Mem->getMemberDecl()->getType();
7520 }
7521
7522 if (const PointerType *Ptr = T->getAs<PointerType>())
7523 T = Ptr->getPointeeType();
7524 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
7525 T = Ptr->getPointeeType();
7526 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
7527 T = MemPtr->getPointeeType();
7528
7529 auto *FTy = T->castAs<FunctionType>();
7530 ReturnsRetained = FTy->getExtInfo().getProducesResult();
7531
7532 // ActOnStmtExpr arranges things so that StmtExprs of retainable
7533 // type always produce a +1 object.
7534 } else if (isa<StmtExpr>(Val: E)) {
7535 ReturnsRetained = true;
7536
7537 // We hit this case with the lambda conversion-to-block optimization;
7538 // we don't want any extra casts here.
7539 } else if (isa<CastExpr>(Val: E) &&
7540 isa<BlockExpr>(Val: cast<CastExpr>(Val: E)->getSubExpr())) {
7541 return E;
7542
7543 // For message sends and property references, we try to find an
7544 // actual method. FIXME: we should infer retention by selector in
7545 // cases where we don't have an actual method.
7546 } else {
7547 ObjCMethodDecl *D = nullptr;
7548 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(Val: E)) {
7549 D = Send->getMethodDecl();
7550 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(Val: E)) {
7551 D = BoxedExpr->getBoxingMethod();
7552 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(Val: E)) {
7553 // Don't do reclaims if we're using the zero-element array
7554 // constant.
7555 if (ArrayLit->getNumElements() == 0 &&
7556 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
7557 return E;
7558
7559 D = ArrayLit->getArrayWithObjectsMethod();
7560 } else if (ObjCDictionaryLiteral *DictLit
7561 = dyn_cast<ObjCDictionaryLiteral>(Val: E)) {
7562 // Don't do reclaims if we're using the zero-element dictionary
7563 // constant.
7564 if (DictLit->getNumElements() == 0 &&
7565 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
7566 return E;
7567
7568 D = DictLit->getDictWithObjectsMethod();
7569 }
7570
7571 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
7572
7573 // Don't do reclaims on performSelector calls; despite their
7574 // return type, the invoked method doesn't necessarily actually
7575 // return an object.
7576 if (!ReturnsRetained &&
7577 D && D->getMethodFamily() == OMF_performSelector)
7578 return E;
7579 }
7580
7581 // Don't reclaim an object of Class type.
7582 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
7583 return E;
7584
7585 Cleanup.setExprNeedsCleanups(true);
7586
7587 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
7588 : CK_ARCReclaimReturnedObject);
7589 return ImplicitCastExpr::Create(Context, T: E->getType(), Kind: ck, Operand: E, BasePath: nullptr,
7590 Cat: VK_PRValue, FPO: FPOptionsOverride());
7591 }
7592
7593 if (E->getType().isDestructedType() == QualType::DK_nontrivial_c_struct)
7594 Cleanup.setExprNeedsCleanups(true);
7595
7596 if (!getLangOpts().CPlusPlus)
7597 return E;
7598
7599 // Search for the base element type (cf. ASTContext::getBaseElementType) with
7600 // a fast path for the common case that the type is directly a RecordType.
7601 const Type *T = Context.getCanonicalType(T: E->getType().getTypePtr());
7602 const RecordType *RT = nullptr;
7603 while (!RT) {
7604 switch (T->getTypeClass()) {
7605 case Type::Record:
7606 RT = cast<RecordType>(Val: T);
7607 break;
7608 case Type::ConstantArray:
7609 case Type::IncompleteArray:
7610 case Type::VariableArray:
7611 case Type::DependentSizedArray:
7612 T = cast<ArrayType>(Val: T)->getElementType().getTypePtr();
7613 break;
7614 default:
7615 return E;
7616 }
7617 }
7618
7619 // That should be enough to guarantee that this type is complete, if we're
7620 // not processing a decltype expression.
7621 CXXRecordDecl *RD = cast<CXXRecordDecl>(Val: RT->getDecl());
7622 if (RD->isInvalidDecl() || RD->isDependentContext())
7623 return E;
7624
7625 bool IsDecltype = ExprEvalContexts.back().ExprContext ==
7626 ExpressionEvaluationContextRecord::EK_Decltype;
7627 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(Class: RD);
7628
7629 if (Destructor) {
7630 MarkFunctionReferenced(Loc: E->getExprLoc(), Func: Destructor);
7631 CheckDestructorAccess(Loc: E->getExprLoc(), Dtor: Destructor,
7632 PDiag: PDiag(DiagID: diag::err_access_dtor_temp)
7633 << E->getType());
7634 if (DiagnoseUseOfDecl(D: Destructor, Locs: E->getExprLoc()))
7635 return ExprError();
7636
7637 // If destructor is trivial, we can avoid the extra copy.
7638 if (Destructor->isTrivial())
7639 return E;
7640
7641 // We need a cleanup, but we don't need to remember the temporary.
7642 Cleanup.setExprNeedsCleanups(true);
7643 }
7644
7645 CXXTemporary *Temp = CXXTemporary::Create(C: Context, Destructor);
7646 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(C: Context, Temp, SubExpr: E);
7647
7648 if (IsDecltype)
7649 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Elt: Bind);
7650
7651 return Bind;
7652}
7653
7654ExprResult
7655Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
7656 if (SubExpr.isInvalid())
7657 return ExprError();
7658
7659 return MaybeCreateExprWithCleanups(SubExpr: SubExpr.get());
7660}
7661
7662Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
7663 assert(SubExpr && "subexpression can't be null!");
7664
7665 CleanupVarDeclMarking();
7666
7667 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
7668 assert(ExprCleanupObjects.size() >= FirstCleanup);
7669 assert(Cleanup.exprNeedsCleanups() ||
7670 ExprCleanupObjects.size() == FirstCleanup);
7671 if (!Cleanup.exprNeedsCleanups())
7672 return SubExpr;
7673
7674 auto Cleanups = llvm::ArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
7675 ExprCleanupObjects.size() - FirstCleanup);
7676
7677 auto *E = ExprWithCleanups::Create(
7678 C: Context, subexpr: SubExpr, CleanupsHaveSideEffects: Cleanup.cleanupsHaveSideEffects(), objects: Cleanups);
7679 DiscardCleanupsInEvaluationContext();
7680
7681 return E;
7682}
7683
7684Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
7685 assert(SubStmt && "sub-statement can't be null!");
7686
7687 CleanupVarDeclMarking();
7688
7689 if (!Cleanup.exprNeedsCleanups())
7690 return SubStmt;
7691
7692 // FIXME: In order to attach the temporaries, wrap the statement into
7693 // a StmtExpr; currently this is only used for asm statements.
7694 // This is hacky, either create a new CXXStmtWithTemporaries statement or
7695 // a new AsmStmtWithTemporaries.
7696 CompoundStmt *CompStmt =
7697 CompoundStmt::Create(C: Context, Stmts: SubStmt, FPFeatures: FPOptionsOverride(),
7698 LB: SourceLocation(), RB: SourceLocation());
7699 Expr *E = new (Context)
7700 StmtExpr(CompStmt, Context.VoidTy, SourceLocation(), SourceLocation(),
7701 /*FIXME TemplateDepth=*/0);
7702 return MaybeCreateExprWithCleanups(SubExpr: E);
7703}
7704
7705ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
7706 assert(ExprEvalContexts.back().ExprContext ==
7707 ExpressionEvaluationContextRecord::EK_Decltype &&
7708 "not in a decltype expression");
7709
7710 ExprResult Result = CheckPlaceholderExpr(E);
7711 if (Result.isInvalid())
7712 return ExprError();
7713 E = Result.get();
7714
7715 // C++11 [expr.call]p11:
7716 // If a function call is a prvalue of object type,
7717 // -- if the function call is either
7718 // -- the operand of a decltype-specifier, or
7719 // -- the right operand of a comma operator that is the operand of a
7720 // decltype-specifier,
7721 // a temporary object is not introduced for the prvalue.
7722
7723 // Recursively rebuild ParenExprs and comma expressions to strip out the
7724 // outermost CXXBindTemporaryExpr, if any.
7725 if (ParenExpr *PE = dyn_cast<ParenExpr>(Val: E)) {
7726 ExprResult SubExpr = ActOnDecltypeExpression(E: PE->getSubExpr());
7727 if (SubExpr.isInvalid())
7728 return ExprError();
7729 if (SubExpr.get() == PE->getSubExpr())
7730 return E;
7731 return ActOnParenExpr(L: PE->getLParen(), R: PE->getRParen(), E: SubExpr.get());
7732 }
7733 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Val: E)) {
7734 if (BO->getOpcode() == BO_Comma) {
7735 ExprResult RHS = ActOnDecltypeExpression(E: BO->getRHS());
7736 if (RHS.isInvalid())
7737 return ExprError();
7738 if (RHS.get() == BO->getRHS())
7739 return E;
7740 return BinaryOperator::Create(C: Context, lhs: BO->getLHS(), rhs: RHS.get(), opc: BO_Comma,
7741 ResTy: BO->getType(), VK: BO->getValueKind(),
7742 OK: BO->getObjectKind(), opLoc: BO->getOperatorLoc(),
7743 FPFeatures: BO->getFPFeatures());
7744 }
7745 }
7746
7747 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(Val: E);
7748 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(Val: TopBind->getSubExpr())
7749 : nullptr;
7750 if (TopCall)
7751 E = TopCall;
7752 else
7753 TopBind = nullptr;
7754
7755 // Disable the special decltype handling now.
7756 ExprEvalContexts.back().ExprContext =
7757 ExpressionEvaluationContextRecord::EK_Other;
7758
7759 Result = CheckUnevaluatedOperand(E);
7760 if (Result.isInvalid())
7761 return ExprError();
7762 E = Result.get();
7763
7764 // In MS mode, don't perform any extra checking of call return types within a
7765 // decltype expression.
7766 if (getLangOpts().MSVCCompat)
7767 return E;
7768
7769 // Perform the semantic checks we delayed until this point.
7770 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
7771 I != N; ++I) {
7772 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
7773 if (Call == TopCall)
7774 continue;
7775
7776 if (CheckCallReturnType(ReturnType: Call->getCallReturnType(Ctx: Context),
7777 Loc: Call->getBeginLoc(), CE: Call, FD: Call->getDirectCallee()))
7778 return ExprError();
7779 }
7780
7781 // Now all relevant types are complete, check the destructors are accessible
7782 // and non-deleted, and annotate them on the temporaries.
7783 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
7784 I != N; ++I) {
7785 CXXBindTemporaryExpr *Bind =
7786 ExprEvalContexts.back().DelayedDecltypeBinds[I];
7787 if (Bind == TopBind)
7788 continue;
7789
7790 CXXTemporary *Temp = Bind->getTemporary();
7791
7792 CXXRecordDecl *RD =
7793 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
7794 CXXDestructorDecl *Destructor = LookupDestructor(Class: RD);
7795 Temp->setDestructor(Destructor);
7796
7797 MarkFunctionReferenced(Loc: Bind->getExprLoc(), Func: Destructor);
7798 CheckDestructorAccess(Loc: Bind->getExprLoc(), Dtor: Destructor,
7799 PDiag: PDiag(DiagID: diag::err_access_dtor_temp)
7800 << Bind->getType());
7801 if (DiagnoseUseOfDecl(D: Destructor, Locs: Bind->getExprLoc()))
7802 return ExprError();
7803
7804 // We need a cleanup, but we don't need to remember the temporary.
7805 Cleanup.setExprNeedsCleanups(true);
7806 }
7807
7808 // Possibly strip off the top CXXBindTemporaryExpr.
7809 return E;
7810}
7811
7812/// Note a set of 'operator->' functions that were used for a member access.
7813static void noteOperatorArrows(Sema &S,
7814 ArrayRef<FunctionDecl *> OperatorArrows) {
7815 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
7816 // FIXME: Make this configurable?
7817 unsigned Limit = 9;
7818 if (OperatorArrows.size() > Limit) {
7819 // Produce Limit-1 normal notes and one 'skipping' note.
7820 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
7821 SkipCount = OperatorArrows.size() - (Limit - 1);
7822 }
7823
7824 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
7825 if (I == SkipStart) {
7826 S.Diag(Loc: OperatorArrows[I]->getLocation(),
7827 DiagID: diag::note_operator_arrows_suppressed)
7828 << SkipCount;
7829 I += SkipCount;
7830 } else {
7831 S.Diag(Loc: OperatorArrows[I]->getLocation(), DiagID: diag::note_operator_arrow_here)
7832 << OperatorArrows[I]->getCallResultType();
7833 ++I;
7834 }
7835 }
7836}
7837
7838ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
7839 SourceLocation OpLoc,
7840 tok::TokenKind OpKind,
7841 ParsedType &ObjectType,
7842 bool &MayBePseudoDestructor) {
7843 // Since this might be a postfix expression, get rid of ParenListExprs.
7844 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, ME: Base);
7845 if (Result.isInvalid()) return ExprError();
7846 Base = Result.get();
7847
7848 Result = CheckPlaceholderExpr(E: Base);
7849 if (Result.isInvalid()) return ExprError();
7850 Base = Result.get();
7851
7852 QualType BaseType = Base->getType();
7853 MayBePseudoDestructor = false;
7854 if (BaseType->isDependentType()) {
7855 // If we have a pointer to a dependent type and are using the -> operator,
7856 // the object type is the type that the pointer points to. We might still
7857 // have enough information about that type to do something useful.
7858 if (OpKind == tok::arrow)
7859 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
7860 BaseType = Ptr->getPointeeType();
7861
7862 ObjectType = ParsedType::make(P: BaseType);
7863 MayBePseudoDestructor = true;
7864 return Base;
7865 }
7866
7867 // C++ [over.match.oper]p8:
7868 // [...] When operator->returns, the operator-> is applied to the value
7869 // returned, with the original second operand.
7870 if (OpKind == tok::arrow) {
7871 QualType StartingType = BaseType;
7872 bool NoArrowOperatorFound = false;
7873 bool FirstIteration = true;
7874 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(Val: CurContext);
7875 // The set of types we've considered so far.
7876 llvm::SmallPtrSet<CanQualType,8> CTypes;
7877 SmallVector<FunctionDecl*, 8> OperatorArrows;
7878 CTypes.insert(Ptr: Context.getCanonicalType(T: BaseType));
7879
7880 while (BaseType->isRecordType()) {
7881 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
7882 Diag(Loc: OpLoc, DiagID: diag::err_operator_arrow_depth_exceeded)
7883 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
7884 noteOperatorArrows(S&: *this, OperatorArrows);
7885 Diag(Loc: OpLoc, DiagID: diag::note_operator_arrow_depth)
7886 << getLangOpts().ArrowDepth;
7887 return ExprError();
7888 }
7889
7890 Result = BuildOverloadedArrowExpr(
7891 S, Base, OpLoc,
7892 // When in a template specialization and on the first loop iteration,
7893 // potentially give the default diagnostic (with the fixit in a
7894 // separate note) instead of having the error reported back to here
7895 // and giving a diagnostic with a fixit attached to the error itself.
7896 NoArrowOperatorFound: (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
7897 ? nullptr
7898 : &NoArrowOperatorFound);
7899 if (Result.isInvalid()) {
7900 if (NoArrowOperatorFound) {
7901 if (FirstIteration) {
7902 Diag(Loc: OpLoc, DiagID: diag::err_typecheck_member_reference_suggestion)
7903 << BaseType << 1 << Base->getSourceRange()
7904 << FixItHint::CreateReplacement(RemoveRange: OpLoc, Code: ".");
7905 OpKind = tok::period;
7906 break;
7907 }
7908 Diag(Loc: OpLoc, DiagID: diag::err_typecheck_member_reference_arrow)
7909 << BaseType << Base->getSourceRange();
7910 CallExpr *CE = dyn_cast<CallExpr>(Val: Base);
7911 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
7912 Diag(Loc: CD->getBeginLoc(),
7913 DiagID: diag::note_member_reference_arrow_from_operator_arrow);
7914 }
7915 }
7916 return ExprError();
7917 }
7918 Base = Result.get();
7919 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Val: Base))
7920 OperatorArrows.push_back(Elt: OpCall->getDirectCallee());
7921 BaseType = Base->getType();
7922 CanQualType CBaseType = Context.getCanonicalType(T: BaseType);
7923 if (!CTypes.insert(Ptr: CBaseType).second) {
7924 Diag(Loc: OpLoc, DiagID: diag::err_operator_arrow_circular) << StartingType;
7925 noteOperatorArrows(S&: *this, OperatorArrows);
7926 return ExprError();
7927 }
7928 FirstIteration = false;
7929 }
7930
7931 if (OpKind == tok::arrow) {
7932 if (BaseType->isPointerType())
7933 BaseType = BaseType->getPointeeType();
7934 else if (auto *AT = Context.getAsArrayType(T: BaseType))
7935 BaseType = AT->getElementType();
7936 }
7937 }
7938
7939 // Objective-C properties allow "." access on Objective-C pointer types,
7940 // so adjust the base type to the object type itself.
7941 if (BaseType->isObjCObjectPointerType())
7942 BaseType = BaseType->getPointeeType();
7943
7944 // C++ [basic.lookup.classref]p2:
7945 // [...] If the type of the object expression is of pointer to scalar
7946 // type, the unqualified-id is looked up in the context of the complete
7947 // postfix-expression.
7948 //
7949 // This also indicates that we could be parsing a pseudo-destructor-name.
7950 // Note that Objective-C class and object types can be pseudo-destructor
7951 // expressions or normal member (ivar or property) access expressions, and
7952 // it's legal for the type to be incomplete if this is a pseudo-destructor
7953 // call. We'll do more incomplete-type checks later in the lookup process,
7954 // so just skip this check for ObjC types.
7955 if (!BaseType->isRecordType()) {
7956 ObjectType = ParsedType::make(P: BaseType);
7957 MayBePseudoDestructor = true;
7958 return Base;
7959 }
7960
7961 // The object type must be complete (or dependent), or
7962 // C++11 [expr.prim.general]p3:
7963 // Unlike the object expression in other contexts, *this is not required to
7964 // be of complete type for purposes of class member access (5.2.5) outside
7965 // the member function body.
7966 if (!BaseType->isDependentType() &&
7967 !isThisOutsideMemberFunctionBody(BaseType) &&
7968 RequireCompleteType(Loc: OpLoc, T: BaseType,
7969 DiagID: diag::err_incomplete_member_access)) {
7970 return CreateRecoveryExpr(Begin: Base->getBeginLoc(), End: Base->getEndLoc(), SubExprs: {Base});
7971 }
7972
7973 // C++ [basic.lookup.classref]p2:
7974 // If the id-expression in a class member access (5.2.5) is an
7975 // unqualified-id, and the type of the object expression is of a class
7976 // type C (or of pointer to a class type C), the unqualified-id is looked
7977 // up in the scope of class C. [...]
7978 ObjectType = ParsedType::make(P: BaseType);
7979 return Base;
7980}
7981
7982static bool CheckArrow(Sema &S, QualType &ObjectType, Expr *&Base,
7983 tok::TokenKind &OpKind, SourceLocation OpLoc) {
7984 if (Base->hasPlaceholderType()) {
7985 ExprResult result = S.CheckPlaceholderExpr(E: Base);
7986 if (result.isInvalid()) return true;
7987 Base = result.get();
7988 }
7989 ObjectType = Base->getType();
7990
7991 // C++ [expr.pseudo]p2:
7992 // The left-hand side of the dot operator shall be of scalar type. The
7993 // left-hand side of the arrow operator shall be of pointer to scalar type.
7994 // This scalar type is the object type.
7995 // Note that this is rather different from the normal handling for the
7996 // arrow operator.
7997 if (OpKind == tok::arrow) {
7998 // The operator requires a prvalue, so perform lvalue conversions.
7999 // Only do this if we might plausibly end with a pointer, as otherwise
8000 // this was likely to be intended to be a '.'.
8001 if (ObjectType->isPointerType() || ObjectType->isArrayType() ||
8002 ObjectType->isFunctionType()) {
8003 ExprResult BaseResult = S.DefaultFunctionArrayLvalueConversion(E: Base);
8004 if (BaseResult.isInvalid())
8005 return true;
8006 Base = BaseResult.get();
8007 ObjectType = Base->getType();
8008 }
8009
8010 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
8011 ObjectType = Ptr->getPointeeType();
8012 } else if (!Base->isTypeDependent()) {
8013 // The user wrote "p->" when they probably meant "p."; fix it.
8014 S.Diag(Loc: OpLoc, DiagID: diag::err_typecheck_member_reference_suggestion)
8015 << ObjectType << true
8016 << FixItHint::CreateReplacement(RemoveRange: OpLoc, Code: ".");
8017 if (S.isSFINAEContext())
8018 return true;
8019
8020 OpKind = tok::period;
8021 }
8022 }
8023
8024 return false;
8025}
8026
8027/// Check if it's ok to try and recover dot pseudo destructor calls on
8028/// pointer objects.
8029static bool
8030canRecoverDotPseudoDestructorCallsOnPointerObjects(Sema &SemaRef,
8031 QualType DestructedType) {
8032 // If this is a record type, check if its destructor is callable.
8033 if (auto *RD = DestructedType->getAsCXXRecordDecl()) {
8034 if (RD->hasDefinition())
8035 if (CXXDestructorDecl *D = SemaRef.LookupDestructor(Class: RD))
8036 return SemaRef.CanUseDecl(D, /*TreatUnavailableAsInvalid=*/false);
8037 return false;
8038 }
8039
8040 // Otherwise, check if it's a type for which it's valid to use a pseudo-dtor.
8041 return DestructedType->isDependentType() || DestructedType->isScalarType() ||
8042 DestructedType->isVectorType();
8043}
8044
8045ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
8046 SourceLocation OpLoc,
8047 tok::TokenKind OpKind,
8048 const CXXScopeSpec &SS,
8049 TypeSourceInfo *ScopeTypeInfo,
8050 SourceLocation CCLoc,
8051 SourceLocation TildeLoc,
8052 PseudoDestructorTypeStorage Destructed) {
8053 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
8054
8055 QualType ObjectType;
8056 if (CheckArrow(S&: *this, ObjectType, Base, OpKind, OpLoc))
8057 return ExprError();
8058
8059 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
8060 !ObjectType->isVectorType()) {
8061 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
8062 Diag(Loc: OpLoc, DiagID: diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
8063 else {
8064 Diag(Loc: OpLoc, DiagID: diag::err_pseudo_dtor_base_not_scalar)
8065 << ObjectType << Base->getSourceRange();
8066 return ExprError();
8067 }
8068 }
8069
8070 // C++ [expr.pseudo]p2:
8071 // [...] The cv-unqualified versions of the object type and of the type
8072 // designated by the pseudo-destructor-name shall be the same type.
8073 if (DestructedTypeInfo) {
8074 QualType DestructedType = DestructedTypeInfo->getType();
8075 SourceLocation DestructedTypeStart =
8076 DestructedTypeInfo->getTypeLoc().getBeginLoc();
8077 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
8078 if (!Context.hasSameUnqualifiedType(T1: DestructedType, T2: ObjectType)) {
8079 // Detect dot pseudo destructor calls on pointer objects, e.g.:
8080 // Foo *foo;
8081 // foo.~Foo();
8082 if (OpKind == tok::period && ObjectType->isPointerType() &&
8083 Context.hasSameUnqualifiedType(T1: DestructedType,
8084 T2: ObjectType->getPointeeType())) {
8085 auto Diagnostic =
8086 Diag(Loc: OpLoc, DiagID: diag::err_typecheck_member_reference_suggestion)
8087 << ObjectType << /*IsArrow=*/0 << Base->getSourceRange();
8088
8089 // Issue a fixit only when the destructor is valid.
8090 if (canRecoverDotPseudoDestructorCallsOnPointerObjects(
8091 SemaRef&: *this, DestructedType))
8092 Diagnostic << FixItHint::CreateReplacement(RemoveRange: OpLoc, Code: "->");
8093
8094 // Recover by setting the object type to the destructed type and the
8095 // operator to '->'.
8096 ObjectType = DestructedType;
8097 OpKind = tok::arrow;
8098 } else {
8099 Diag(Loc: DestructedTypeStart, DiagID: diag::err_pseudo_dtor_type_mismatch)
8100 << ObjectType << DestructedType << Base->getSourceRange()
8101 << DestructedTypeInfo->getTypeLoc().getSourceRange();
8102
8103 // Recover by setting the destructed type to the object type.
8104 DestructedType = ObjectType;
8105 DestructedTypeInfo =
8106 Context.getTrivialTypeSourceInfo(T: ObjectType, Loc: DestructedTypeStart);
8107 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
8108 }
8109 } else if (DestructedType.getObjCLifetime() !=
8110 ObjectType.getObjCLifetime()) {
8111
8112 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
8113 // Okay: just pretend that the user provided the correctly-qualified
8114 // type.
8115 } else {
8116 Diag(Loc: DestructedTypeStart, DiagID: diag::err_arc_pseudo_dtor_inconstant_quals)
8117 << ObjectType << DestructedType << Base->getSourceRange()
8118 << DestructedTypeInfo->getTypeLoc().getSourceRange();
8119 }
8120
8121 // Recover by setting the destructed type to the object type.
8122 DestructedType = ObjectType;
8123 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(T: ObjectType,
8124 Loc: DestructedTypeStart);
8125 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
8126 }
8127 }
8128 }
8129
8130 // C++ [expr.pseudo]p2:
8131 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
8132 // form
8133 //
8134 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
8135 //
8136 // shall designate the same scalar type.
8137 if (ScopeTypeInfo) {
8138 QualType ScopeType = ScopeTypeInfo->getType();
8139 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
8140 !Context.hasSameUnqualifiedType(T1: ScopeType, T2: ObjectType)) {
8141
8142 Diag(Loc: ScopeTypeInfo->getTypeLoc().getSourceRange().getBegin(),
8143 DiagID: diag::err_pseudo_dtor_type_mismatch)
8144 << ObjectType << ScopeType << Base->getSourceRange()
8145 << ScopeTypeInfo->getTypeLoc().getSourceRange();
8146
8147 ScopeType = QualType();
8148 ScopeTypeInfo = nullptr;
8149 }
8150 }
8151
8152 Expr *Result
8153 = new (Context) CXXPseudoDestructorExpr(Context, Base,
8154 OpKind == tok::arrow, OpLoc,
8155 SS.getWithLocInContext(Context),
8156 ScopeTypeInfo,
8157 CCLoc,
8158 TildeLoc,
8159 Destructed);
8160
8161 return Result;
8162}
8163
8164ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
8165 SourceLocation OpLoc,
8166 tok::TokenKind OpKind,
8167 CXXScopeSpec &SS,
8168 UnqualifiedId &FirstTypeName,
8169 SourceLocation CCLoc,
8170 SourceLocation TildeLoc,
8171 UnqualifiedId &SecondTypeName) {
8172 assert((FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
8173 FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
8174 "Invalid first type name in pseudo-destructor");
8175 assert((SecondTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
8176 SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
8177 "Invalid second type name in pseudo-destructor");
8178
8179 QualType ObjectType;
8180 if (CheckArrow(S&: *this, ObjectType, Base, OpKind, OpLoc))
8181 return ExprError();
8182
8183 // Compute the object type that we should use for name lookup purposes. Only
8184 // record types and dependent types matter.
8185 ParsedType ObjectTypePtrForLookup;
8186 if (!SS.isSet()) {
8187 if (ObjectType->isRecordType())
8188 ObjectTypePtrForLookup = ParsedType::make(P: ObjectType);
8189 else if (ObjectType->isDependentType())
8190 ObjectTypePtrForLookup = ParsedType::make(P: Context.DependentTy);
8191 }
8192
8193 // Convert the name of the type being destructed (following the ~) into a
8194 // type (with source-location information).
8195 QualType DestructedType;
8196 TypeSourceInfo *DestructedTypeInfo = nullptr;
8197 PseudoDestructorTypeStorage Destructed;
8198 if (SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
8199 ParsedType T = getTypeName(II: *SecondTypeName.Identifier,
8200 NameLoc: SecondTypeName.StartLocation,
8201 S, SS: &SS, isClassName: true, HasTrailingDot: false, ObjectType: ObjectTypePtrForLookup,
8202 /*IsCtorOrDtorName*/true);
8203 if (!T &&
8204 ((SS.isSet() && !computeDeclContext(SS, EnteringContext: false)) ||
8205 (!SS.isSet() && ObjectType->isDependentType()))) {
8206 // The name of the type being destroyed is a dependent name, and we
8207 // couldn't find anything useful in scope. Just store the identifier and
8208 // it's location, and we'll perform (qualified) name lookup again at
8209 // template instantiation time.
8210 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
8211 SecondTypeName.StartLocation);
8212 } else if (!T) {
8213 Diag(Loc: SecondTypeName.StartLocation,
8214 DiagID: diag::err_pseudo_dtor_destructor_non_type)
8215 << SecondTypeName.Identifier << ObjectType;
8216 if (isSFINAEContext())
8217 return ExprError();
8218
8219 // Recover by assuming we had the right type all along.
8220 DestructedType = ObjectType;
8221 } else
8222 DestructedType = GetTypeFromParser(Ty: T, TInfo: &DestructedTypeInfo);
8223 } else {
8224 // Resolve the template-id to a type.
8225 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
8226 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8227 TemplateId->NumArgs);
8228 TypeResult T = ActOnTemplateIdType(S,
8229 SS,
8230 TemplateKWLoc: TemplateId->TemplateKWLoc,
8231 Template: TemplateId->Template,
8232 TemplateII: TemplateId->Name,
8233 TemplateIILoc: TemplateId->TemplateNameLoc,
8234 LAngleLoc: TemplateId->LAngleLoc,
8235 TemplateArgs: TemplateArgsPtr,
8236 RAngleLoc: TemplateId->RAngleLoc,
8237 /*IsCtorOrDtorName*/true);
8238 if (T.isInvalid() || !T.get()) {
8239 // Recover by assuming we had the right type all along.
8240 DestructedType = ObjectType;
8241 } else
8242 DestructedType = GetTypeFromParser(Ty: T.get(), TInfo: &DestructedTypeInfo);
8243 }
8244
8245 // If we've performed some kind of recovery, (re-)build the type source
8246 // information.
8247 if (!DestructedType.isNull()) {
8248 if (!DestructedTypeInfo)
8249 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(T: DestructedType,
8250 Loc: SecondTypeName.StartLocation);
8251 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
8252 }
8253
8254 // Convert the name of the scope type (the type prior to '::') into a type.
8255 TypeSourceInfo *ScopeTypeInfo = nullptr;
8256 QualType ScopeType;
8257 if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
8258 FirstTypeName.Identifier) {
8259 if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
8260 ParsedType T = getTypeName(II: *FirstTypeName.Identifier,
8261 NameLoc: FirstTypeName.StartLocation,
8262 S, SS: &SS, isClassName: true, HasTrailingDot: false, ObjectType: ObjectTypePtrForLookup,
8263 /*IsCtorOrDtorName*/true);
8264 if (!T) {
8265 Diag(Loc: FirstTypeName.StartLocation,
8266 DiagID: diag::err_pseudo_dtor_destructor_non_type)
8267 << FirstTypeName.Identifier << ObjectType;
8268
8269 if (isSFINAEContext())
8270 return ExprError();
8271
8272 // Just drop this type. It's unnecessary anyway.
8273 ScopeType = QualType();
8274 } else
8275 ScopeType = GetTypeFromParser(Ty: T, TInfo: &ScopeTypeInfo);
8276 } else {
8277 // Resolve the template-id to a type.
8278 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
8279 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
8280 TemplateId->NumArgs);
8281 TypeResult T = ActOnTemplateIdType(S,
8282 SS,
8283 TemplateKWLoc: TemplateId->TemplateKWLoc,
8284 Template: TemplateId->Template,
8285 TemplateII: TemplateId->Name,
8286 TemplateIILoc: TemplateId->TemplateNameLoc,
8287 LAngleLoc: TemplateId->LAngleLoc,
8288 TemplateArgs: TemplateArgsPtr,
8289 RAngleLoc: TemplateId->RAngleLoc,
8290 /*IsCtorOrDtorName*/true);
8291 if (T.isInvalid() || !T.get()) {
8292 // Recover by dropping this type.
8293 ScopeType = QualType();
8294 } else
8295 ScopeType = GetTypeFromParser(Ty: T.get(), TInfo: &ScopeTypeInfo);
8296 }
8297 }
8298
8299 if (!ScopeType.isNull() && !ScopeTypeInfo)
8300 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(T: ScopeType,
8301 Loc: FirstTypeName.StartLocation);
8302
8303
8304 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
8305 ScopeTypeInfo, CCLoc, TildeLoc,
8306 Destructed);
8307}
8308
8309ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
8310 SourceLocation OpLoc,
8311 tok::TokenKind OpKind,
8312 SourceLocation TildeLoc,
8313 const DeclSpec& DS) {
8314 QualType ObjectType;
8315 QualType T;
8316 TypeLocBuilder TLB;
8317 if (CheckArrow(S&: *this, ObjectType, Base, OpKind, OpLoc))
8318 return ExprError();
8319
8320 switch (DS.getTypeSpecType()) {
8321 case DeclSpec::TST_decltype_auto: {
8322 Diag(Loc: DS.getTypeSpecTypeLoc(), DiagID: diag::err_decltype_auto_invalid);
8323 return true;
8324 }
8325 case DeclSpec::TST_decltype: {
8326 T = BuildDecltypeType(E: DS.getRepAsExpr(), /*AsUnevaluated=*/false);
8327 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
8328 DecltypeTL.setDecltypeLoc(DS.getTypeSpecTypeLoc());
8329 DecltypeTL.setRParenLoc(DS.getTypeofParensRange().getEnd());
8330 break;
8331 }
8332 case DeclSpec::TST_typename_pack_indexing: {
8333 T = ActOnPackIndexingType(Pattern: DS.getRepAsType().get(), IndexExpr: DS.getPackIndexingExpr(),
8334 Loc: DS.getBeginLoc(), EllipsisLoc: DS.getEllipsisLoc());
8335 TLB.pushTrivial(Context&: getASTContext(),
8336 T: cast<PackIndexingType>(Val: T.getTypePtr())->getPattern(),
8337 Loc: DS.getBeginLoc());
8338 PackIndexingTypeLoc PITL = TLB.push<PackIndexingTypeLoc>(T);
8339 PITL.setEllipsisLoc(DS.getEllipsisLoc());
8340 break;
8341 }
8342 default:
8343 llvm_unreachable("Unsupported type in pseudo destructor");
8344 }
8345 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
8346 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
8347
8348 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS: CXXScopeSpec(),
8349 ScopeTypeInfo: nullptr, CCLoc: SourceLocation(), TildeLoc,
8350 Destructed);
8351}
8352
8353ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
8354 SourceLocation RParen) {
8355 // If the operand is an unresolved lookup expression, the expression is ill-
8356 // formed per [over.over]p1, because overloaded function names cannot be used
8357 // without arguments except in explicit contexts.
8358 ExprResult R = CheckPlaceholderExpr(E: Operand);
8359 if (R.isInvalid())
8360 return R;
8361
8362 R = CheckUnevaluatedOperand(E: R.get());
8363 if (R.isInvalid())
8364 return ExprError();
8365
8366 Operand = R.get();
8367
8368 if (!inTemplateInstantiation() && !Operand->isInstantiationDependent() &&
8369 Operand->HasSideEffects(Ctx: Context, IncludePossibleEffects: false)) {
8370 // The expression operand for noexcept is in an unevaluated expression
8371 // context, so side effects could result in unintended consequences.
8372 Diag(Loc: Operand->getExprLoc(), DiagID: diag::warn_side_effects_unevaluated_context);
8373 }
8374
8375 CanThrowResult CanThrow = canThrow(E: Operand);
8376 return new (Context)
8377 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
8378}
8379
8380ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
8381 Expr *Operand, SourceLocation RParen) {
8382 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
8383}
8384
8385static void MaybeDecrementCount(
8386 Expr *E, llvm::DenseMap<const VarDecl *, int> &RefsMinusAssignments) {
8387 DeclRefExpr *LHS = nullptr;
8388 bool IsCompoundAssign = false;
8389 bool isIncrementDecrementUnaryOp = false;
8390 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Val: E)) {
8391 if (BO->getLHS()->getType()->isDependentType() ||
8392 BO->getRHS()->getType()->isDependentType()) {
8393 if (BO->getOpcode() != BO_Assign)
8394 return;
8395 } else if (!BO->isAssignmentOp())
8396 return;
8397 else
8398 IsCompoundAssign = BO->isCompoundAssignmentOp();
8399 LHS = dyn_cast<DeclRefExpr>(Val: BO->getLHS());
8400 } else if (CXXOperatorCallExpr *COCE = dyn_cast<CXXOperatorCallExpr>(Val: E)) {
8401 if (COCE->getOperator() != OO_Equal)
8402 return;
8403 LHS = dyn_cast<DeclRefExpr>(Val: COCE->getArg(Arg: 0));
8404 } else if (UnaryOperator *UO = dyn_cast<UnaryOperator>(Val: E)) {
8405 if (!UO->isIncrementDecrementOp())
8406 return;
8407 isIncrementDecrementUnaryOp = true;
8408 LHS = dyn_cast<DeclRefExpr>(Val: UO->getSubExpr());
8409 }
8410 if (!LHS)
8411 return;
8412 VarDecl *VD = dyn_cast<VarDecl>(Val: LHS->getDecl());
8413 if (!VD)
8414 return;
8415 // Don't decrement RefsMinusAssignments if volatile variable with compound
8416 // assignment (+=, ...) or increment/decrement unary operator to avoid
8417 // potential unused-but-set-variable warning.
8418 if ((IsCompoundAssign || isIncrementDecrementUnaryOp) &&
8419 VD->getType().isVolatileQualified())
8420 return;
8421 auto iter = RefsMinusAssignments.find(Val: VD);
8422 if (iter == RefsMinusAssignments.end())
8423 return;
8424 iter->getSecond()--;
8425}
8426
8427/// Perform the conversions required for an expression used in a
8428/// context that ignores the result.
8429ExprResult Sema::IgnoredValueConversions(Expr *E) {
8430 MaybeDecrementCount(E, RefsMinusAssignments);
8431
8432 if (E->hasPlaceholderType()) {
8433 ExprResult result = CheckPlaceholderExpr(E);
8434 if (result.isInvalid()) return E;
8435 E = result.get();
8436 }
8437
8438 if (getLangOpts().CPlusPlus) {
8439 // The C++11 standard defines the notion of a discarded-value expression;
8440 // normally, we don't need to do anything to handle it, but if it is a
8441 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
8442 // conversion.
8443 if (getLangOpts().CPlusPlus11 && E->isReadIfDiscardedInCPlusPlus11()) {
8444 ExprResult Res = DefaultLvalueConversion(E);
8445 if (Res.isInvalid())
8446 return E;
8447 E = Res.get();
8448 } else {
8449 // Per C++2a [expr.ass]p5, a volatile assignment is not deprecated if
8450 // it occurs as a discarded-value expression.
8451 CheckUnusedVolatileAssignment(E);
8452 }
8453
8454 // C++1z:
8455 // If the expression is a prvalue after this optional conversion, the
8456 // temporary materialization conversion is applied.
8457 //
8458 // We do not materialize temporaries by default in order to avoid creating
8459 // unnecessary temporary objects. If we skip this step, IR generation is
8460 // able to synthesize the storage for itself in the aggregate case, and
8461 // adding the extra node to the AST is just clutter.
8462 if (isInLifetimeExtendingContext() && getLangOpts().CPlusPlus17 &&
8463 E->isPRValue() && !E->getType()->isVoidType()) {
8464 ExprResult Res = TemporaryMaterializationConversion(E);
8465 if (Res.isInvalid())
8466 return E;
8467 E = Res.get();
8468 }
8469 return E;
8470 }
8471
8472 // C99 6.3.2.1:
8473 // [Except in specific positions,] an lvalue that does not have
8474 // array type is converted to the value stored in the
8475 // designated object (and is no longer an lvalue).
8476 if (E->isPRValue()) {
8477 // In C, function designators (i.e. expressions of function type)
8478 // are r-values, but we still want to do function-to-pointer decay
8479 // on them. This is both technically correct and convenient for
8480 // some clients.
8481 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
8482 return DefaultFunctionArrayConversion(E);
8483
8484 return E;
8485 }
8486
8487 // GCC seems to also exclude expressions of incomplete enum type.
8488 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
8489 if (!T->getDecl()->isComplete()) {
8490 // FIXME: stupid workaround for a codegen bug!
8491 E = ImpCastExprToType(E, Type: Context.VoidTy, CK: CK_ToVoid).get();
8492 return E;
8493 }
8494 }
8495
8496 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
8497 if (Res.isInvalid())
8498 return E;
8499 E = Res.get();
8500
8501 if (!E->getType()->isVoidType())
8502 RequireCompleteType(Loc: E->getExprLoc(), T: E->getType(),
8503 DiagID: diag::err_incomplete_type);
8504 return E;
8505}
8506
8507ExprResult Sema::CheckUnevaluatedOperand(Expr *E) {
8508 // Per C++2a [expr.ass]p5, a volatile assignment is not deprecated if
8509 // it occurs as an unevaluated operand.
8510 CheckUnusedVolatileAssignment(E);
8511
8512 return E;
8513}
8514
8515// If we can unambiguously determine whether Var can never be used
8516// in a constant expression, return true.
8517// - if the variable and its initializer are non-dependent, then
8518// we can unambiguously check if the variable is a constant expression.
8519// - if the initializer is not value dependent - we can determine whether
8520// it can be used to initialize a constant expression. If Init can not
8521// be used to initialize a constant expression we conclude that Var can
8522// never be a constant expression.
8523// - FXIME: if the initializer is dependent, we can still do some analysis and
8524// identify certain cases unambiguously as non-const by using a Visitor:
8525// - such as those that involve odr-use of a ParmVarDecl, involve a new
8526// delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
8527static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
8528 ASTContext &Context) {
8529 if (isa<ParmVarDecl>(Val: Var)) return true;
8530 const VarDecl *DefVD = nullptr;
8531
8532 // If there is no initializer - this can not be a constant expression.
8533 const Expr *Init = Var->getAnyInitializer(D&: DefVD);
8534 if (!Init)
8535 return true;
8536 assert(DefVD);
8537 if (DefVD->isWeak())
8538 return false;
8539
8540 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
8541 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
8542 // of value-dependent expressions, and use it here to determine whether the
8543 // initializer is a potential constant expression.
8544 return false;
8545 }
8546
8547 return !Var->isUsableInConstantExpressions(C: Context);
8548}
8549
8550/// Check if the current lambda has any potential captures
8551/// that must be captured by any of its enclosing lambdas that are ready to
8552/// capture. If there is a lambda that can capture a nested
8553/// potential-capture, go ahead and do so. Also, check to see if any
8554/// variables are uncaptureable or do not involve an odr-use so do not
8555/// need to be captured.
8556
8557static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
8558 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
8559
8560 assert(!S.isUnevaluatedContext());
8561 assert(S.CurContext->isDependentContext());
8562#ifndef NDEBUG
8563 DeclContext *DC = S.CurContext;
8564 while (isa_and_nonnull<CapturedDecl>(DC))
8565 DC = DC->getParent();
8566 assert(
8567 CurrentLSI->CallOperator == DC &&
8568 "The current call operator must be synchronized with Sema's CurContext");
8569#endif // NDEBUG
8570
8571 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
8572
8573 // All the potentially captureable variables in the current nested
8574 // lambda (within a generic outer lambda), must be captured by an
8575 // outer lambda that is enclosed within a non-dependent context.
8576 CurrentLSI->visitPotentialCaptures(Callback: [&](ValueDecl *Var, Expr *VarExpr) {
8577 // If the variable is clearly identified as non-odr-used and the full
8578 // expression is not instantiation dependent, only then do we not
8579 // need to check enclosing lambda's for speculative captures.
8580 // For e.g.:
8581 // Even though 'x' is not odr-used, it should be captured.
8582 // int test() {
8583 // const int x = 10;
8584 // auto L = [=](auto a) {
8585 // (void) +x + a;
8586 // };
8587 // }
8588 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(CapturingVarExpr: VarExpr) &&
8589 !IsFullExprInstantiationDependent)
8590 return;
8591
8592 VarDecl *UnderlyingVar = Var->getPotentiallyDecomposedVarDecl();
8593 if (!UnderlyingVar)
8594 return;
8595
8596 // If we have a capture-capable lambda for the variable, go ahead and
8597 // capture the variable in that lambda (and all its enclosing lambdas).
8598 if (const std::optional<unsigned> Index =
8599 getStackIndexOfNearestEnclosingCaptureCapableLambda(
8600 FunctionScopes: S.FunctionScopes, VarToCapture: Var, S))
8601 S.MarkCaptureUsedInEnclosingContext(Capture: Var, Loc: VarExpr->getExprLoc(), CapturingScopeIndex: *Index);
8602 const bool IsVarNeverAConstantExpression =
8603 VariableCanNeverBeAConstantExpression(Var: UnderlyingVar, Context&: S.Context);
8604 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
8605 // This full expression is not instantiation dependent or the variable
8606 // can not be used in a constant expression - which means
8607 // this variable must be odr-used here, so diagnose a
8608 // capture violation early, if the variable is un-captureable.
8609 // This is purely for diagnosing errors early. Otherwise, this
8610 // error would get diagnosed when the lambda becomes capture ready.
8611 QualType CaptureType, DeclRefType;
8612 SourceLocation ExprLoc = VarExpr->getExprLoc();
8613 if (S.tryCaptureVariable(Var, Loc: ExprLoc, Kind: S.TryCapture_Implicit,
8614 /*EllipsisLoc*/ SourceLocation(),
8615 /*BuildAndDiagnose*/false, CaptureType,
8616 DeclRefType, FunctionScopeIndexToStopAt: nullptr)) {
8617 // We will never be able to capture this variable, and we need
8618 // to be able to in any and all instantiations, so diagnose it.
8619 S.tryCaptureVariable(Var, Loc: ExprLoc, Kind: S.TryCapture_Implicit,
8620 /*EllipsisLoc*/ SourceLocation(),
8621 /*BuildAndDiagnose*/true, CaptureType,
8622 DeclRefType, FunctionScopeIndexToStopAt: nullptr);
8623 }
8624 }
8625 });
8626
8627 // Check if 'this' needs to be captured.
8628 if (CurrentLSI->hasPotentialThisCapture()) {
8629 // If we have a capture-capable lambda for 'this', go ahead and capture
8630 // 'this' in that lambda (and all its enclosing lambdas).
8631 if (const std::optional<unsigned> Index =
8632 getStackIndexOfNearestEnclosingCaptureCapableLambda(
8633 FunctionScopes: S.FunctionScopes, /*0 is 'this'*/ VarToCapture: nullptr, S)) {
8634 const unsigned FunctionScopeIndexOfCapturableLambda = *Index;
8635 S.CheckCXXThisCapture(Loc: CurrentLSI->PotentialThisCaptureLocation,
8636 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
8637 FunctionScopeIndexToStopAt: &FunctionScopeIndexOfCapturableLambda);
8638 }
8639 }
8640
8641 // Reset all the potential captures at the end of each full-expression.
8642 CurrentLSI->clearPotentialCaptures();
8643}
8644
8645static ExprResult attemptRecovery(Sema &SemaRef,
8646 const TypoCorrectionConsumer &Consumer,
8647 const TypoCorrection &TC) {
8648 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
8649 Consumer.getLookupResult().getLookupKind());
8650 const CXXScopeSpec *SS = Consumer.getSS();
8651 CXXScopeSpec NewSS;
8652
8653 // Use an approprate CXXScopeSpec for building the expr.
8654 if (auto *NNS = TC.getCorrectionSpecifier())
8655 NewSS.MakeTrivial(Context&: SemaRef.Context, Qualifier: NNS, R: TC.getCorrectionRange());
8656 else if (SS && !TC.WillReplaceSpecifier())
8657 NewSS = *SS;
8658
8659 if (auto *ND = TC.getFoundDecl()) {
8660 R.setLookupName(ND->getDeclName());
8661 R.addDecl(D: ND);
8662 if (ND->isCXXClassMember()) {
8663 // Figure out the correct naming class to add to the LookupResult.
8664 CXXRecordDecl *Record = nullptr;
8665 if (auto *NNS = TC.getCorrectionSpecifier())
8666 Record = NNS->getAsType()->getAsCXXRecordDecl();
8667 if (!Record)
8668 Record =
8669 dyn_cast<CXXRecordDecl>(Val: ND->getDeclContext()->getRedeclContext());
8670 if (Record)
8671 R.setNamingClass(Record);
8672
8673 // Detect and handle the case where the decl might be an implicit
8674 // member.
8675 if (SemaRef.isPotentialImplicitMemberAccess(
8676 SS: NewSS, R, IsAddressOfOperand: Consumer.isAddressOfOperand()))
8677 return SemaRef.BuildPossibleImplicitMemberExpr(
8678 SS: NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
8679 /*TemplateArgs*/ nullptr, /*S*/ nullptr);
8680 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(Val: ND)) {
8681 return SemaRef.ObjC().LookupInObjCMethod(LookUp&: R, S: Consumer.getScope(),
8682 II: Ivar->getIdentifier());
8683 }
8684 }
8685
8686 return SemaRef.BuildDeclarationNameExpr(SS: NewSS, R, /*NeedsADL*/ false,
8687 /*AcceptInvalidDecl*/ true);
8688}
8689
8690namespace {
8691class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
8692 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
8693
8694public:
8695 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
8696 : TypoExprs(TypoExprs) {}
8697 bool VisitTypoExpr(TypoExpr *TE) {
8698 TypoExprs.insert(X: TE);
8699 return true;
8700 }
8701};
8702
8703class TransformTypos : public TreeTransform<TransformTypos> {
8704 typedef TreeTransform<TransformTypos> BaseTransform;
8705
8706 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
8707 // process of being initialized.
8708 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
8709 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
8710 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
8711 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
8712
8713 /// Emit diagnostics for all of the TypoExprs encountered.
8714 ///
8715 /// If the TypoExprs were successfully corrected, then the diagnostics should
8716 /// suggest the corrections. Otherwise the diagnostics will not suggest
8717 /// anything (having been passed an empty TypoCorrection).
8718 ///
8719 /// If we've failed to correct due to ambiguous corrections, we need to
8720 /// be sure to pass empty corrections and replacements. Otherwise it's
8721 /// possible that the Consumer has a TypoCorrection that failed to ambiguity
8722 /// and we don't want to report those diagnostics.
8723 void EmitAllDiagnostics(bool IsAmbiguous) {
8724 for (TypoExpr *TE : TypoExprs) {
8725 auto &State = SemaRef.getTypoExprState(TE);
8726 if (State.DiagHandler) {
8727 TypoCorrection TC = IsAmbiguous
8728 ? TypoCorrection() : State.Consumer->getCurrentCorrection();
8729 ExprResult Replacement = IsAmbiguous ? ExprError() : TransformCache[TE];
8730
8731 // Extract the NamedDecl from the transformed TypoExpr and add it to the
8732 // TypoCorrection, replacing the existing decls. This ensures the right
8733 // NamedDecl is used in diagnostics e.g. in the case where overload
8734 // resolution was used to select one from several possible decls that
8735 // had been stored in the TypoCorrection.
8736 if (auto *ND = getDeclFromExpr(
8737 E: Replacement.isInvalid() ? nullptr : Replacement.get()))
8738 TC.setCorrectionDecl(ND);
8739
8740 State.DiagHandler(TC);
8741 }
8742 SemaRef.clearDelayedTypo(TE);
8743 }
8744 }
8745
8746 /// Try to advance the typo correction state of the first unfinished TypoExpr.
8747 /// We allow advancement of the correction stream by removing it from the
8748 /// TransformCache which allows `TransformTypoExpr` to advance during the
8749 /// next transformation attempt.
8750 ///
8751 /// Any substitution attempts for the previous TypoExprs (which must have been
8752 /// finished) will need to be retried since it's possible that they will now
8753 /// be invalid given the latest advancement.
8754 ///
8755 /// We need to be sure that we're making progress - it's possible that the
8756 /// tree is so malformed that the transform never makes it to the
8757 /// `TransformTypoExpr`.
8758 ///
8759 /// Returns true if there are any untried correction combinations.
8760 bool CheckAndAdvanceTypoExprCorrectionStreams() {
8761 for (auto *TE : TypoExprs) {
8762 auto &State = SemaRef.getTypoExprState(TE);
8763 TransformCache.erase(Val: TE);
8764 if (!State.Consumer->hasMadeAnyCorrectionProgress())
8765 return false;
8766 if (!State.Consumer->finished())
8767 return true;
8768 State.Consumer->resetCorrectionStream();
8769 }
8770 return false;
8771 }
8772
8773 NamedDecl *getDeclFromExpr(Expr *E) {
8774 if (auto *OE = dyn_cast_or_null<OverloadExpr>(Val: E))
8775 E = OverloadResolution[OE];
8776
8777 if (!E)
8778 return nullptr;
8779 if (auto *DRE = dyn_cast<DeclRefExpr>(Val: E))
8780 return DRE->getFoundDecl();
8781 if (auto *ME = dyn_cast<MemberExpr>(Val: E))
8782 return ME->getFoundDecl();
8783 // FIXME: Add any other expr types that could be seen by the delayed typo
8784 // correction TreeTransform for which the corresponding TypoCorrection could
8785 // contain multiple decls.
8786 return nullptr;
8787 }
8788
8789 ExprResult TryTransform(Expr *E) {
8790 Sema::SFINAETrap Trap(SemaRef);
8791 ExprResult Res = TransformExpr(E);
8792 if (Trap.hasErrorOccurred() || Res.isInvalid())
8793 return ExprError();
8794
8795 return ExprFilter(Res.get());
8796 }
8797
8798 // Since correcting typos may intoduce new TypoExprs, this function
8799 // checks for new TypoExprs and recurses if it finds any. Note that it will
8800 // only succeed if it is able to correct all typos in the given expression.
8801 ExprResult CheckForRecursiveTypos(ExprResult Res, bool &IsAmbiguous) {
8802 if (Res.isInvalid()) {
8803 return Res;
8804 }
8805 // Check to see if any new TypoExprs were created. If so, we need to recurse
8806 // to check their validity.
8807 Expr *FixedExpr = Res.get();
8808
8809 auto SavedTypoExprs = std::move(TypoExprs);
8810 auto SavedAmbiguousTypoExprs = std::move(AmbiguousTypoExprs);
8811 TypoExprs.clear();
8812 AmbiguousTypoExprs.clear();
8813
8814 FindTypoExprs(TypoExprs).TraverseStmt(S: FixedExpr);
8815 if (!TypoExprs.empty()) {
8816 // Recurse to handle newly created TypoExprs. If we're not able to
8817 // handle them, discard these TypoExprs.
8818 ExprResult RecurResult =
8819 RecursiveTransformLoop(E: FixedExpr, IsAmbiguous);
8820 if (RecurResult.isInvalid()) {
8821 Res = ExprError();
8822 // Recursive corrections didn't work, wipe them away and don't add
8823 // them to the TypoExprs set. Remove them from Sema's TypoExpr list
8824 // since we don't want to clear them twice. Note: it's possible the
8825 // TypoExprs were created recursively and thus won't be in our
8826 // Sema's TypoExprs - they were created in our `RecursiveTransformLoop`.
8827 auto &SemaTypoExprs = SemaRef.TypoExprs;
8828 for (auto *TE : TypoExprs) {
8829 TransformCache.erase(Val: TE);
8830 SemaRef.clearDelayedTypo(TE);
8831
8832 auto SI = find(Range&: SemaTypoExprs, Val: TE);
8833 if (SI != SemaTypoExprs.end()) {
8834 SemaTypoExprs.erase(CI: SI);
8835 }
8836 }
8837 } else {
8838 // TypoExpr is valid: add newly created TypoExprs since we were
8839 // able to correct them.
8840 Res = RecurResult;
8841 SavedTypoExprs.set_union(TypoExprs);
8842 }
8843 }
8844
8845 TypoExprs = std::move(SavedTypoExprs);
8846 AmbiguousTypoExprs = std::move(SavedAmbiguousTypoExprs);
8847
8848 return Res;
8849 }
8850
8851 // Try to transform the given expression, looping through the correction
8852 // candidates with `CheckAndAdvanceTypoExprCorrectionStreams`.
8853 //
8854 // If valid ambiguous typo corrections are seen, `IsAmbiguous` is set to
8855 // true and this method immediately will return an `ExprError`.
8856 ExprResult RecursiveTransformLoop(Expr *E, bool &IsAmbiguous) {
8857 ExprResult Res;
8858 auto SavedTypoExprs = std::move(SemaRef.TypoExprs);
8859 SemaRef.TypoExprs.clear();
8860
8861 while (true) {
8862 Res = CheckForRecursiveTypos(Res: TryTransform(E), IsAmbiguous);
8863
8864 // Recursion encountered an ambiguous correction. This means that our
8865 // correction itself is ambiguous, so stop now.
8866 if (IsAmbiguous)
8867 break;
8868
8869 // If the transform is still valid after checking for any new typos,
8870 // it's good to go.
8871 if (!Res.isInvalid())
8872 break;
8873
8874 // The transform was invalid, see if we have any TypoExprs with untried
8875 // correction candidates.
8876 if (!CheckAndAdvanceTypoExprCorrectionStreams())
8877 break;
8878 }
8879
8880 // If we found a valid result, double check to make sure it's not ambiguous.
8881 if (!IsAmbiguous && !Res.isInvalid() && !AmbiguousTypoExprs.empty()) {
8882 auto SavedTransformCache =
8883 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2>(TransformCache);
8884
8885 // Ensure none of the TypoExprs have multiple typo correction candidates
8886 // with the same edit length that pass all the checks and filters.
8887 while (!AmbiguousTypoExprs.empty()) {
8888 auto TE = AmbiguousTypoExprs.back();
8889
8890 // TryTransform itself can create new Typos, adding them to the TypoExpr map
8891 // and invalidating our TypoExprState, so always fetch it instead of storing.
8892 SemaRef.getTypoExprState(TE).Consumer->saveCurrentPosition();
8893
8894 TypoCorrection TC = SemaRef.getTypoExprState(TE).Consumer->peekNextCorrection();
8895 TypoCorrection Next;
8896 do {
8897 // Fetch the next correction by erasing the typo from the cache and calling
8898 // `TryTransform` which will iterate through corrections in
8899 // `TransformTypoExpr`.
8900 TransformCache.erase(Val: TE);
8901 ExprResult AmbigRes = CheckForRecursiveTypos(Res: TryTransform(E), IsAmbiguous);
8902
8903 if (!AmbigRes.isInvalid() || IsAmbiguous) {
8904 SemaRef.getTypoExprState(TE).Consumer->resetCorrectionStream();
8905 SavedTransformCache.erase(Val: TE);
8906 Res = ExprError();
8907 IsAmbiguous = true;
8908 break;
8909 }
8910 } while ((Next = SemaRef.getTypoExprState(TE).Consumer->peekNextCorrection()) &&
8911 Next.getEditDistance(Normalized: false) == TC.getEditDistance(Normalized: false));
8912
8913 if (IsAmbiguous)
8914 break;
8915
8916 AmbiguousTypoExprs.remove(X: TE);
8917 SemaRef.getTypoExprState(TE).Consumer->restoreSavedPosition();
8918 TransformCache[TE] = SavedTransformCache[TE];
8919 }
8920 TransformCache = std::move(SavedTransformCache);
8921 }
8922
8923 // Wipe away any newly created TypoExprs that we don't know about. Since we
8924 // clear any invalid TypoExprs in `CheckForRecursiveTypos`, this is only
8925 // possible if a `TypoExpr` is created during a transformation but then
8926 // fails before we can discover it.
8927 auto &SemaTypoExprs = SemaRef.TypoExprs;
8928 for (auto Iterator = SemaTypoExprs.begin(); Iterator != SemaTypoExprs.end();) {
8929 auto TE = *Iterator;
8930 auto FI = find(Range&: TypoExprs, Val: TE);
8931 if (FI != TypoExprs.end()) {
8932 Iterator++;
8933 continue;
8934 }
8935 SemaRef.clearDelayedTypo(TE);
8936 Iterator = SemaTypoExprs.erase(CI: Iterator);
8937 }
8938 SemaRef.TypoExprs = std::move(SavedTypoExprs);
8939
8940 return Res;
8941 }
8942
8943public:
8944 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
8945 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
8946
8947 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
8948 MultiExprArg Args,
8949 SourceLocation RParenLoc,
8950 Expr *ExecConfig = nullptr) {
8951 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
8952 RParenLoc, ExecConfig);
8953 if (auto *OE = dyn_cast<OverloadExpr>(Val: Callee)) {
8954 if (Result.isUsable()) {
8955 Expr *ResultCall = Result.get();
8956 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(Val: ResultCall))
8957 ResultCall = BE->getSubExpr();
8958 if (auto *CE = dyn_cast<CallExpr>(Val: ResultCall))
8959 OverloadResolution[OE] = CE->getCallee();
8960 }
8961 }
8962 return Result;
8963 }
8964
8965 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
8966
8967 ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
8968
8969 ExprResult Transform(Expr *E) {
8970 bool IsAmbiguous = false;
8971 ExprResult Res = RecursiveTransformLoop(E, IsAmbiguous);
8972
8973 if (!Res.isUsable())
8974 FindTypoExprs(TypoExprs).TraverseStmt(S: E);
8975
8976 EmitAllDiagnostics(IsAmbiguous);
8977
8978 return Res;
8979 }
8980
8981 ExprResult TransformTypoExpr(TypoExpr *E) {
8982 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
8983 // cached transformation result if there is one and the TypoExpr isn't the
8984 // first one that was encountered.
8985 auto &CacheEntry = TransformCache[E];
8986 if (!TypoExprs.insert(X: E) && !CacheEntry.isUnset()) {
8987 return CacheEntry;
8988 }
8989
8990 auto &State = SemaRef.getTypoExprState(TE: E);
8991 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
8992
8993 // For the first TypoExpr and an uncached TypoExpr, find the next likely
8994 // typo correction and return it.
8995 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
8996 if (InitDecl && TC.getFoundDecl() == InitDecl)
8997 continue;
8998 // FIXME: If we would typo-correct to an invalid declaration, it's
8999 // probably best to just suppress all errors from this typo correction.
9000 ExprResult NE = State.RecoveryHandler ?
9001 State.RecoveryHandler(SemaRef, E, TC) :
9002 attemptRecovery(SemaRef, Consumer: *State.Consumer, TC);
9003 if (!NE.isInvalid()) {
9004 // Check whether there may be a second viable correction with the same
9005 // edit distance; if so, remember this TypoExpr may have an ambiguous
9006 // correction so it can be more thoroughly vetted later.
9007 TypoCorrection Next;
9008 if ((Next = State.Consumer->peekNextCorrection()) &&
9009 Next.getEditDistance(Normalized: false) == TC.getEditDistance(Normalized: false)) {
9010 AmbiguousTypoExprs.insert(X: E);
9011 } else {
9012 AmbiguousTypoExprs.remove(X: E);
9013 }
9014 assert(!NE.isUnset() &&
9015 "Typo was transformed into a valid-but-null ExprResult");
9016 return CacheEntry = NE;
9017 }
9018 }
9019 return CacheEntry = ExprError();
9020 }
9021};
9022}
9023
9024ExprResult
9025Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
9026 bool RecoverUncorrectedTypos,
9027 llvm::function_ref<ExprResult(Expr *)> Filter) {
9028 // If the current evaluation context indicates there are uncorrected typos
9029 // and the current expression isn't guaranteed to not have typos, try to
9030 // resolve any TypoExpr nodes that might be in the expression.
9031 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
9032 (E->isTypeDependent() || E->isValueDependent() ||
9033 E->isInstantiationDependent())) {
9034 auto TyposResolved = DelayedTypos.size();
9035 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
9036 TyposResolved -= DelayedTypos.size();
9037 if (Result.isInvalid() || Result.get() != E) {
9038 ExprEvalContexts.back().NumTypos -= TyposResolved;
9039 if (Result.isInvalid() && RecoverUncorrectedTypos) {
9040 struct TyposReplace : TreeTransform<TyposReplace> {
9041 TyposReplace(Sema &SemaRef) : TreeTransform(SemaRef) {}
9042 ExprResult TransformTypoExpr(clang::TypoExpr *E) {
9043 return this->SemaRef.CreateRecoveryExpr(Begin: E->getBeginLoc(),
9044 End: E->getEndLoc(), SubExprs: {});
9045 }
9046 } TT(*this);
9047 return TT.TransformExpr(E);
9048 }
9049 return Result;
9050 }
9051 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
9052 }
9053 return E;
9054}
9055
9056ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
9057 bool DiscardedValue, bool IsConstexpr,
9058 bool IsTemplateArgument) {
9059 ExprResult FullExpr = FE;
9060
9061 if (!FullExpr.get())
9062 return ExprError();
9063
9064 if (!IsTemplateArgument && DiagnoseUnexpandedParameterPack(E: FullExpr.get()))
9065 return ExprError();
9066
9067 if (DiscardedValue) {
9068 // Top-level expressions default to 'id' when we're in a debugger.
9069 if (getLangOpts().DebuggerCastResultToId &&
9070 FullExpr.get()->getType() == Context.UnknownAnyTy) {
9071 FullExpr = forceUnknownAnyToType(E: FullExpr.get(), ToType: Context.getObjCIdType());
9072 if (FullExpr.isInvalid())
9073 return ExprError();
9074 }
9075
9076 FullExpr = CheckPlaceholderExpr(E: FullExpr.get());
9077 if (FullExpr.isInvalid())
9078 return ExprError();
9079
9080 FullExpr = IgnoredValueConversions(E: FullExpr.get());
9081 if (FullExpr.isInvalid())
9082 return ExprError();
9083
9084 DiagnoseUnusedExprResult(S: FullExpr.get(), DiagID: diag::warn_unused_expr);
9085 }
9086
9087 FullExpr = CorrectDelayedTyposInExpr(E: FullExpr.get(), /*InitDecl=*/nullptr,
9088 /*RecoverUncorrectedTypos=*/true);
9089 if (FullExpr.isInvalid())
9090 return ExprError();
9091
9092 CheckCompletedExpr(E: FullExpr.get(), CheckLoc: CC, IsConstexpr);
9093
9094 // At the end of this full expression (which could be a deeply nested
9095 // lambda), if there is a potential capture within the nested lambda,
9096 // have the outer capture-able lambda try and capture it.
9097 // Consider the following code:
9098 // void f(int, int);
9099 // void f(const int&, double);
9100 // void foo() {
9101 // const int x = 10, y = 20;
9102 // auto L = [=](auto a) {
9103 // auto M = [=](auto b) {
9104 // f(x, b); <-- requires x to be captured by L and M
9105 // f(y, a); <-- requires y to be captured by L, but not all Ms
9106 // };
9107 // };
9108 // }
9109
9110 // FIXME: Also consider what happens for something like this that involves
9111 // the gnu-extension statement-expressions or even lambda-init-captures:
9112 // void f() {
9113 // const int n = 0;
9114 // auto L = [&](auto a) {
9115 // +n + ({ 0; a; });
9116 // };
9117 // }
9118 //
9119 // Here, we see +n, and then the full-expression 0; ends, so we don't
9120 // capture n (and instead remove it from our list of potential captures),
9121 // and then the full-expression +n + ({ 0; }); ends, but it's too late
9122 // for us to see that we need to capture n after all.
9123
9124 LambdaScopeInfo *const CurrentLSI =
9125 getCurLambda(/*IgnoreCapturedRegions=*/IgnoreNonLambdaCapturingScope: true);
9126 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
9127 // even if CurContext is not a lambda call operator. Refer to that Bug Report
9128 // for an example of the code that might cause this asynchrony.
9129 // By ensuring we are in the context of a lambda's call operator
9130 // we can fix the bug (we only need to check whether we need to capture
9131 // if we are within a lambda's body); but per the comments in that
9132 // PR, a proper fix would entail :
9133 // "Alternative suggestion:
9134 // - Add to Sema an integer holding the smallest (outermost) scope
9135 // index that we are *lexically* within, and save/restore/set to
9136 // FunctionScopes.size() in InstantiatingTemplate's
9137 // constructor/destructor.
9138 // - Teach the handful of places that iterate over FunctionScopes to
9139 // stop at the outermost enclosing lexical scope."
9140 DeclContext *DC = CurContext;
9141 while (isa_and_nonnull<CapturedDecl>(Val: DC))
9142 DC = DC->getParent();
9143 const bool IsInLambdaDeclContext = isLambdaCallOperator(DC);
9144 if (IsInLambdaDeclContext && CurrentLSI &&
9145 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
9146 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
9147 S&: *this);
9148 return MaybeCreateExprWithCleanups(SubExpr: FullExpr);
9149}
9150
9151StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
9152 if (!FullStmt) return StmtError();
9153
9154 return MaybeCreateStmtWithCleanups(SubStmt: FullStmt);
9155}
9156
9157Sema::IfExistsResult
9158Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
9159 CXXScopeSpec &SS,
9160 const DeclarationNameInfo &TargetNameInfo) {
9161 DeclarationName TargetName = TargetNameInfo.getName();
9162 if (!TargetName)
9163 return IER_DoesNotExist;
9164
9165 // If the name itself is dependent, then the result is dependent.
9166 if (TargetName.isDependentName())
9167 return IER_Dependent;
9168
9169 // Do the redeclaration lookup in the current scope.
9170 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
9171 RedeclarationKind::NotForRedeclaration);
9172 LookupParsedName(R, S, SS: &SS, /*ObjectType=*/QualType());
9173 R.suppressDiagnostics();
9174
9175 switch (R.getResultKind()) {
9176 case LookupResult::Found:
9177 case LookupResult::FoundOverloaded:
9178 case LookupResult::FoundUnresolvedValue:
9179 case LookupResult::Ambiguous:
9180 return IER_Exists;
9181
9182 case LookupResult::NotFound:
9183 return IER_DoesNotExist;
9184
9185 case LookupResult::NotFoundInCurrentInstantiation:
9186 return IER_Dependent;
9187 }
9188
9189 llvm_unreachable("Invalid LookupResult Kind!");
9190}
9191
9192Sema::IfExistsResult
9193Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
9194 bool IsIfExists, CXXScopeSpec &SS,
9195 UnqualifiedId &Name) {
9196 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
9197
9198 // Check for an unexpanded parameter pack.
9199 auto UPPC = IsIfExists ? UPPC_IfExists : UPPC_IfNotExists;
9200 if (DiagnoseUnexpandedParameterPack(SS, UPPC) ||
9201 DiagnoseUnexpandedParameterPack(NameInfo: TargetNameInfo, UPPC))
9202 return IER_Error;
9203
9204 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);
9205}
9206
9207concepts::Requirement *Sema::ActOnSimpleRequirement(Expr *E) {
9208 return BuildExprRequirement(E, /*IsSimple=*/IsSatisfied: true,
9209 /*NoexceptLoc=*/SourceLocation(),
9210 /*ReturnTypeRequirement=*/{});
9211}
9212
9213concepts::Requirement *Sema::ActOnTypeRequirement(
9214 SourceLocation TypenameKWLoc, CXXScopeSpec &SS, SourceLocation NameLoc,
9215 const IdentifierInfo *TypeName, TemplateIdAnnotation *TemplateId) {
9216 assert(((!TypeName && TemplateId) || (TypeName && !TemplateId)) &&
9217 "Exactly one of TypeName and TemplateId must be specified.");
9218 TypeSourceInfo *TSI = nullptr;
9219 if (TypeName) {
9220 QualType T =
9221 CheckTypenameType(Keyword: ElaboratedTypeKeyword::Typename, KeywordLoc: TypenameKWLoc,
9222 QualifierLoc: SS.getWithLocInContext(Context), II: *TypeName, IILoc: NameLoc,
9223 TSI: &TSI, /*DeducedTSTContext=*/false);
9224 if (T.isNull())
9225 return nullptr;
9226 } else {
9227 ASTTemplateArgsPtr ArgsPtr(TemplateId->getTemplateArgs(),
9228 TemplateId->NumArgs);
9229 TypeResult T = ActOnTypenameType(S: CurScope, TypenameLoc: TypenameKWLoc, SS,
9230 TemplateLoc: TemplateId->TemplateKWLoc,
9231 TemplateName: TemplateId->Template, TemplateII: TemplateId->Name,
9232 TemplateIILoc: TemplateId->TemplateNameLoc,
9233 LAngleLoc: TemplateId->LAngleLoc, TemplateArgs: ArgsPtr,
9234 RAngleLoc: TemplateId->RAngleLoc);
9235 if (T.isInvalid())
9236 return nullptr;
9237 if (GetTypeFromParser(Ty: T.get(), TInfo: &TSI).isNull())
9238 return nullptr;
9239 }
9240 return BuildTypeRequirement(Type: TSI);
9241}
9242
9243concepts::Requirement *
9244Sema::ActOnCompoundRequirement(Expr *E, SourceLocation NoexceptLoc) {
9245 return BuildExprRequirement(E, /*IsSimple=*/IsSatisfied: false, NoexceptLoc,
9246 /*ReturnTypeRequirement=*/{});
9247}
9248
9249concepts::Requirement *
9250Sema::ActOnCompoundRequirement(
9251 Expr *E, SourceLocation NoexceptLoc, CXXScopeSpec &SS,
9252 TemplateIdAnnotation *TypeConstraint, unsigned Depth) {
9253 // C++2a [expr.prim.req.compound] p1.3.3
9254 // [..] the expression is deduced against an invented function template
9255 // F [...] F is a void function template with a single type template
9256 // parameter T declared with the constrained-parameter. Form a new
9257 // cv-qualifier-seq cv by taking the union of const and volatile specifiers
9258 // around the constrained-parameter. F has a single parameter whose
9259 // type-specifier is cv T followed by the abstract-declarator. [...]
9260 //
9261 // The cv part is done in the calling function - we get the concept with
9262 // arguments and the abstract declarator with the correct CV qualification and
9263 // have to synthesize T and the single parameter of F.
9264 auto &II = Context.Idents.get(Name: "expr-type");
9265 auto *TParam = TemplateTypeParmDecl::Create(C: Context, DC: CurContext,
9266 KeyLoc: SourceLocation(),
9267 NameLoc: SourceLocation(), D: Depth,
9268 /*Index=*/P: 0, Id: &II,
9269 /*Typename=*/true,
9270 /*ParameterPack=*/false,
9271 /*HasTypeConstraint=*/true);
9272
9273 if (BuildTypeConstraint(SS, TypeConstraint, ConstrainedParameter: TParam,
9274 /*EllipsisLoc=*/SourceLocation(),
9275 /*AllowUnexpandedPack=*/true))
9276 // Just produce a requirement with no type requirements.
9277 return BuildExprRequirement(E, /*IsSimple=*/IsSatisfied: false, NoexceptLoc, ReturnTypeRequirement: {});
9278
9279 auto *TPL = TemplateParameterList::Create(C: Context, TemplateLoc: SourceLocation(),
9280 LAngleLoc: SourceLocation(),
9281 Params: ArrayRef<NamedDecl *>(TParam),
9282 RAngleLoc: SourceLocation(),
9283 /*RequiresClause=*/nullptr);
9284 return BuildExprRequirement(
9285 E, /*IsSimple=*/IsSatisfied: false, NoexceptLoc,
9286 ReturnTypeRequirement: concepts::ExprRequirement::ReturnTypeRequirement(TPL));
9287}
9288
9289concepts::ExprRequirement *
9290Sema::BuildExprRequirement(
9291 Expr *E, bool IsSimple, SourceLocation NoexceptLoc,
9292 concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
9293 auto Status = concepts::ExprRequirement::SS_Satisfied;
9294 ConceptSpecializationExpr *SubstitutedConstraintExpr = nullptr;
9295 if (E->isInstantiationDependent() || E->getType()->isPlaceholderType() ||
9296 ReturnTypeRequirement.isDependent())
9297 Status = concepts::ExprRequirement::SS_Dependent;
9298 else if (NoexceptLoc.isValid() && canThrow(E) == CanThrowResult::CT_Can)
9299 Status = concepts::ExprRequirement::SS_NoexceptNotMet;
9300 else if (ReturnTypeRequirement.isSubstitutionFailure())
9301 Status = concepts::ExprRequirement::SS_TypeRequirementSubstitutionFailure;
9302 else if (ReturnTypeRequirement.isTypeConstraint()) {
9303 // C++2a [expr.prim.req]p1.3.3
9304 // The immediately-declared constraint ([temp]) of decltype((E)) shall
9305 // be satisfied.
9306 TemplateParameterList *TPL =
9307 ReturnTypeRequirement.getTypeConstraintTemplateParameterList();
9308 QualType MatchedType =
9309 Context.getReferenceQualifiedType(e: E).getCanonicalType();
9310 llvm::SmallVector<TemplateArgument, 1> Args;
9311 Args.push_back(Elt: TemplateArgument(MatchedType));
9312
9313 auto *Param = cast<TemplateTypeParmDecl>(Val: TPL->getParam(Idx: 0));
9314
9315 MultiLevelTemplateArgumentList MLTAL(Param, Args, /*Final=*/false);
9316 MLTAL.addOuterRetainedLevels(Num: TPL->getDepth());
9317 const TypeConstraint *TC = Param->getTypeConstraint();
9318 assert(TC && "Type Constraint cannot be null here");
9319 auto *IDC = TC->getImmediatelyDeclaredConstraint();
9320 assert(IDC && "ImmediatelyDeclaredConstraint can't be null here.");
9321 ExprResult Constraint = SubstExpr(E: IDC, TemplateArgs: MLTAL);
9322 if (Constraint.isInvalid()) {
9323 return new (Context) concepts::ExprRequirement(
9324 concepts::createSubstDiagAt(S&: *this, Location: IDC->getExprLoc(),
9325 Printer: [&](llvm::raw_ostream &OS) {
9326 IDC->printPretty(OS, /*Helper=*/nullptr,
9327 Policy: getPrintingPolicy());
9328 }),
9329 IsSimple, NoexceptLoc, ReturnTypeRequirement);
9330 }
9331 SubstitutedConstraintExpr =
9332 cast<ConceptSpecializationExpr>(Val: Constraint.get());
9333 if (!SubstitutedConstraintExpr->isSatisfied())
9334 Status = concepts::ExprRequirement::SS_ConstraintsNotSatisfied;
9335 }
9336 return new (Context) concepts::ExprRequirement(E, IsSimple, NoexceptLoc,
9337 ReturnTypeRequirement, Status,
9338 SubstitutedConstraintExpr);
9339}
9340
9341concepts::ExprRequirement *
9342Sema::BuildExprRequirement(
9343 concepts::Requirement::SubstitutionDiagnostic *ExprSubstitutionDiagnostic,
9344 bool IsSimple, SourceLocation NoexceptLoc,
9345 concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement) {
9346 return new (Context) concepts::ExprRequirement(ExprSubstitutionDiagnostic,
9347 IsSimple, NoexceptLoc,
9348 ReturnTypeRequirement);
9349}
9350
9351concepts::TypeRequirement *
9352Sema::BuildTypeRequirement(TypeSourceInfo *Type) {
9353 return new (Context) concepts::TypeRequirement(Type);
9354}
9355
9356concepts::TypeRequirement *
9357Sema::BuildTypeRequirement(
9358 concepts::Requirement::SubstitutionDiagnostic *SubstDiag) {
9359 return new (Context) concepts::TypeRequirement(SubstDiag);
9360}
9361
9362concepts::Requirement *Sema::ActOnNestedRequirement(Expr *Constraint) {
9363 return BuildNestedRequirement(E: Constraint);
9364}
9365
9366concepts::NestedRequirement *
9367Sema::BuildNestedRequirement(Expr *Constraint) {
9368 ConstraintSatisfaction Satisfaction;
9369 if (!Constraint->isInstantiationDependent() &&
9370 CheckConstraintSatisfaction(Template: nullptr, ConstraintExprs: {Constraint}, /*TemplateArgs=*/TemplateArgLists: {},
9371 TemplateIDRange: Constraint->getSourceRange(), Satisfaction))
9372 return nullptr;
9373 return new (Context) concepts::NestedRequirement(Context, Constraint,
9374 Satisfaction);
9375}
9376
9377concepts::NestedRequirement *
9378Sema::BuildNestedRequirement(StringRef InvalidConstraintEntity,
9379 const ASTConstraintSatisfaction &Satisfaction) {
9380 return new (Context) concepts::NestedRequirement(
9381 InvalidConstraintEntity,
9382 ASTConstraintSatisfaction::Rebuild(C: Context, Satisfaction));
9383}
9384
9385RequiresExprBodyDecl *
9386Sema::ActOnStartRequiresExpr(SourceLocation RequiresKWLoc,
9387 ArrayRef<ParmVarDecl *> LocalParameters,
9388 Scope *BodyScope) {
9389 assert(BodyScope);
9390
9391 RequiresExprBodyDecl *Body = RequiresExprBodyDecl::Create(C&: Context, DC: CurContext,
9392 StartLoc: RequiresKWLoc);
9393
9394 PushDeclContext(S: BodyScope, DC: Body);
9395
9396 for (ParmVarDecl *Param : LocalParameters) {
9397 if (Param->hasDefaultArg())
9398 // C++2a [expr.prim.req] p4
9399 // [...] A local parameter of a requires-expression shall not have a
9400 // default argument. [...]
9401 Diag(Loc: Param->getDefaultArgRange().getBegin(),
9402 DiagID: diag::err_requires_expr_local_parameter_default_argument);
9403 // Ignore default argument and move on
9404
9405 Param->setDeclContext(Body);
9406 // If this has an identifier, add it to the scope stack.
9407 if (Param->getIdentifier()) {
9408 CheckShadow(S: BodyScope, D: Param);
9409 PushOnScopeChains(D: Param, S: BodyScope);
9410 }
9411 }
9412 return Body;
9413}
9414
9415void Sema::ActOnFinishRequiresExpr() {
9416 assert(CurContext && "DeclContext imbalance!");
9417 CurContext = CurContext->getLexicalParent();
9418 assert(CurContext && "Popped translation unit!");
9419}
9420
9421ExprResult Sema::ActOnRequiresExpr(
9422 SourceLocation RequiresKWLoc, RequiresExprBodyDecl *Body,
9423 SourceLocation LParenLoc, ArrayRef<ParmVarDecl *> LocalParameters,
9424 SourceLocation RParenLoc, ArrayRef<concepts::Requirement *> Requirements,
9425 SourceLocation ClosingBraceLoc) {
9426 auto *RE = RequiresExpr::Create(C&: Context, RequiresKWLoc, Body, LParenLoc,
9427 LocalParameters, RParenLoc, Requirements,
9428 RBraceLoc: ClosingBraceLoc);
9429 if (DiagnoseUnexpandedParameterPackInRequiresExpr(RE))
9430 return ExprError();
9431 return RE;
9432}
9433