1//===--- ParseTemplate.cpp - Template Parsing -----------------------------===//
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// This file implements parsing of C++ templates.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/AST/ASTContext.h"
14#include "clang/AST/DeclTemplate.h"
15#include "clang/AST/ExprCXX.h"
16#include "clang/Basic/DiagnosticParse.h"
17#include "clang/Parse/Parser.h"
18#include "clang/Parse/RAIIObjectsForParser.h"
19#include "clang/Sema/DeclSpec.h"
20#include "clang/Sema/EnterExpressionEvaluationContext.h"
21#include "clang/Sema/ParsedTemplate.h"
22#include "clang/Sema/Scope.h"
23using namespace clang;
24
25unsigned Parser::ReenterTemplateScopes(MultiParseScope &S, Decl *D) {
26 return Actions.ActOnReenterTemplateScope(Template: D, EnterScope: [&] {
27 S.Enter(ScopeFlags: Scope::TemplateParamScope);
28 return Actions.getCurScope();
29 });
30}
31
32Parser::DeclGroupPtrTy
33Parser::ParseDeclarationStartingWithTemplate(DeclaratorContext Context,
34 SourceLocation &DeclEnd,
35 ParsedAttributes &AccessAttrs) {
36 ObjCDeclContextSwitch ObjCDC(*this);
37
38 if (Tok.is(K: tok::kw_template) && NextToken().isNot(K: tok::less)) {
39 return ParseExplicitInstantiation(Context, ExternLoc: SourceLocation(), TemplateLoc: ConsumeToken(),
40 DeclEnd, AccessAttrs,
41 AS: AccessSpecifier::AS_none);
42 }
43 return ParseTemplateDeclarationOrSpecialization(Context, DeclEnd, AccessAttrs,
44 AS: AccessSpecifier::AS_none);
45}
46
47Parser::DeclGroupPtrTy Parser::ParseTemplateDeclarationOrSpecialization(
48 DeclaratorContext Context, SourceLocation &DeclEnd,
49 ParsedAttributes &AccessAttrs, AccessSpecifier AS) {
50 assert(Tok.isOneOf(tok::kw_export, tok::kw_template) &&
51 "Token does not start a template declaration.");
52
53 MultiParseScope TemplateParamScopes(*this);
54
55 // Tell the action that names should be checked in the context of
56 // the declaration to come.
57 ParsingDeclRAIIObject
58 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
59
60 // Parse multiple levels of template headers within this template
61 // parameter scope, e.g.,
62 //
63 // template<typename T>
64 // template<typename U>
65 // class A<T>::B { ... };
66 //
67 // We parse multiple levels non-recursively so that we can build a
68 // single data structure containing all of the template parameter
69 // lists to easily differentiate between the case above and:
70 //
71 // template<typename T>
72 // class A {
73 // template<typename U> class B;
74 // };
75 //
76 // In the first case, the action for declaring A<T>::B receives
77 // both template parameter lists. In the second case, the action for
78 // defining A<T>::B receives just the inner template parameter list
79 // (and retrieves the outer template parameter list from its
80 // context).
81 bool isSpecialization = true;
82 bool LastParamListWasEmpty = false;
83 TemplateParameterLists ParamLists;
84 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
85
86 do {
87 // Consume the 'export', if any.
88 SourceLocation ExportLoc;
89 TryConsumeToken(Expected: tok::kw_export, Loc&: ExportLoc);
90
91 // Consume the 'template', which should be here.
92 SourceLocation TemplateLoc;
93 if (!TryConsumeToken(Expected: tok::kw_template, Loc&: TemplateLoc)) {
94 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected_template);
95 return nullptr;
96 }
97
98 // Parse the '<' template-parameter-list '>'
99 SourceLocation LAngleLoc, RAngleLoc;
100 SmallVector<NamedDecl*, 4> TemplateParams;
101 if (ParseTemplateParameters(TemplateScopes&: TemplateParamScopes,
102 Depth: CurTemplateDepthTracker.getDepth(),
103 TemplateParams, LAngleLoc, RAngleLoc)) {
104 // Skip until the semi-colon or a '}'.
105 SkipUntil(T: tok::r_brace, Flags: StopAtSemi | StopBeforeMatch);
106 TryConsumeToken(Expected: tok::semi);
107 return nullptr;
108 }
109
110 ExprResult OptionalRequiresClauseConstraintER;
111 if (!TemplateParams.empty()) {
112 isSpecialization = false;
113 ++CurTemplateDepthTracker;
114
115 if (TryConsumeToken(Expected: tok::kw_requires)) {
116 OptionalRequiresClauseConstraintER =
117 Actions.ActOnRequiresClause(ConstraintExpr: ParseConstraintLogicalOrExpression(
118 /*IsTrailingRequiresClause=*/false));
119 if (!OptionalRequiresClauseConstraintER.isUsable()) {
120 // Skip until the semi-colon or a '}'.
121 SkipUntil(T: tok::r_brace, Flags: StopAtSemi | StopBeforeMatch);
122 TryConsumeToken(Expected: tok::semi);
123 return nullptr;
124 }
125 }
126 } else {
127 LastParamListWasEmpty = true;
128 }
129
130 ParamLists.push_back(Elt: Actions.ActOnTemplateParameterList(
131 Depth: CurTemplateDepthTracker.getDepth(), ExportLoc, TemplateLoc, LAngleLoc,
132 Params: TemplateParams, RAngleLoc, RequiresClause: OptionalRequiresClauseConstraintER.get()));
133 } while (Tok.isOneOf(Ks: tok::kw_export, Ks: tok::kw_template));
134
135 ParsedTemplateInfo TemplateInfo(&ParamLists, isSpecialization,
136 LastParamListWasEmpty);
137
138 // Parse the actual template declaration.
139 if (Tok.is(K: tok::kw_concept)) {
140 Decl *ConceptDecl = ParseConceptDefinition(TemplateInfo, DeclEnd);
141 // We need to explicitly pass ConceptDecl to ParsingDeclRAIIObject, so that
142 // delayed diagnostics (e.g. warn_deprecated) have a Decl to work with.
143 ParsingTemplateParams.complete(D: ConceptDecl);
144 return Actions.ConvertDeclToDeclGroup(Ptr: ConceptDecl);
145 }
146
147 return ParseDeclarationAfterTemplate(
148 Context, TemplateInfo, DiagsFromParams&: ParsingTemplateParams, DeclEnd, AccessAttrs, AS);
149}
150
151Parser::DeclGroupPtrTy Parser::ParseTemplateDeclarationOrSpecialization(
152 DeclaratorContext Context, SourceLocation &DeclEnd, AccessSpecifier AS) {
153 ParsedAttributes AccessAttrs(AttrFactory);
154 return ParseTemplateDeclarationOrSpecialization(Context, DeclEnd, AccessAttrs,
155 AS);
156}
157
158Parser::DeclGroupPtrTy Parser::ParseDeclarationAfterTemplate(
159 DeclaratorContext Context, ParsedTemplateInfo &TemplateInfo,
160 ParsingDeclRAIIObject &DiagsFromTParams, SourceLocation &DeclEnd,
161 ParsedAttributes &AccessAttrs, AccessSpecifier AS) {
162 assert(TemplateInfo.Kind != ParsedTemplateKind::NonTemplate &&
163 "Template information required");
164
165 if (Tok.is(K: tok::kw_static_assert)) {
166 // A static_assert declaration may not be templated.
167 Diag(Loc: Tok.getLocation(), DiagID: diag::err_templated_invalid_declaration)
168 << TemplateInfo.getSourceRange();
169 // Parse the static_assert declaration to improve error recovery.
170 return Actions.ConvertDeclToDeclGroup(
171 Ptr: ParseStaticAssertDeclaration(DeclEnd));
172 }
173
174 // We are parsing a member template.
175 if (Context == DeclaratorContext::Member)
176 return ParseCXXClassMemberDeclaration(AS, Attr&: AccessAttrs, TemplateInfo,
177 DiagsFromTParams: &DiagsFromTParams);
178
179 ParsedAttributes DeclAttrs(AttrFactory);
180 ParsedAttributes DeclSpecAttrs(AttrFactory);
181
182 // GNU attributes are applied to the declaration specification while the
183 // standard attributes are applied to the declaration. We parse the two
184 // attribute sets into different containters so we can apply them during
185 // the regular parsing process.
186 while (MaybeParseCXX11Attributes(Attrs&: DeclAttrs) ||
187 MaybeParseGNUAttributes(Attrs&: DeclSpecAttrs))
188 ;
189
190 if (Tok.is(K: tok::kw_using))
191 return ParseUsingDirectiveOrDeclaration(Context, TemplateInfo, DeclEnd,
192 Attrs&: DeclAttrs);
193
194 // Parse the declaration specifiers, stealing any diagnostics from
195 // the template parameters.
196 ParsingDeclSpec DS(*this, &DiagsFromTParams);
197 DS.SetRangeStart(DeclSpecAttrs.Range.getBegin());
198 DS.SetRangeEnd(DeclSpecAttrs.Range.getEnd());
199 DS.takeAttributesFrom(attrs&: DeclSpecAttrs);
200
201 ParseDeclarationSpecifiers(DS, TemplateInfo, AS,
202 DSC: getDeclSpecContextFromDeclaratorContext(Context));
203
204 if (Tok.is(K: tok::semi)) {
205 ProhibitAttributes(Attrs&: DeclAttrs);
206 DeclEnd = ConsumeToken();
207 RecordDecl *AnonRecord = nullptr;
208 Decl *Decl = Actions.ParsedFreeStandingDeclSpec(
209 S: getCurScope(), AS, DS, DeclAttrs: ParsedAttributesView::none(),
210 TemplateParams: TemplateInfo.TemplateParams ? *TemplateInfo.TemplateParams
211 : MultiTemplateParamsArg(),
212 IsExplicitInstantiation: TemplateInfo.Kind == ParsedTemplateKind::ExplicitInstantiation,
213 AnonRecord);
214 Actions.ActOnDefinedDeclarationSpecifier(D: Decl);
215 assert(!AnonRecord &&
216 "Anonymous unions/structs should not be valid with template");
217 DS.complete(D: Decl);
218 return Actions.ConvertDeclToDeclGroup(Ptr: Decl);
219 }
220
221 if (DS.hasTagDefinition())
222 Actions.ActOnDefinedDeclarationSpecifier(D: DS.getRepAsDecl());
223
224 // Move the attributes from the prefix into the DS.
225 if (TemplateInfo.Kind == ParsedTemplateKind::ExplicitInstantiation)
226 ProhibitAttributes(Attrs&: DeclAttrs);
227
228 return ParseDeclGroup(DS, Context, Attrs&: DeclAttrs, TemplateInfo, DeclEnd: &DeclEnd);
229}
230
231Decl *
232Parser::ParseConceptDefinition(const ParsedTemplateInfo &TemplateInfo,
233 SourceLocation &DeclEnd) {
234 assert(TemplateInfo.Kind != ParsedTemplateKind::NonTemplate &&
235 "Template information required");
236 assert(Tok.is(tok::kw_concept) &&
237 "ParseConceptDefinition must be called when at a 'concept' keyword");
238
239 ConsumeToken(); // Consume 'concept'
240
241 SourceLocation BoolKWLoc;
242 if (TryConsumeToken(Expected: tok::kw_bool, Loc&: BoolKWLoc))
243 Diag(Loc: Tok.getLocation(), DiagID: diag::err_concept_legacy_bool_keyword) <<
244 FixItHint::CreateRemoval(RemoveRange: SourceLocation(BoolKWLoc));
245
246 DiagnoseAndSkipCXX11Attributes();
247
248 CXXScopeSpec SS;
249 if (ParseOptionalCXXScopeSpecifier(
250 SS, /*ObjectType=*/nullptr,
251 /*ObjectHasErrors=*/false, /*EnteringContext=*/false,
252 /*MayBePseudoDestructor=*/nullptr,
253 /*IsTypename=*/false, /*LastII=*/nullptr, /*OnlyNamespace=*/true) ||
254 SS.isInvalid()) {
255 SkipUntil(T: tok::semi);
256 return nullptr;
257 }
258
259 if (SS.isNotEmpty())
260 Diag(Loc: SS.getBeginLoc(),
261 DiagID: diag::err_concept_definition_not_identifier);
262
263 UnqualifiedId Result;
264 if (ParseUnqualifiedId(SS, /*ObjectType=*/nullptr,
265 /*ObjectHadErrors=*/false, /*EnteringContext=*/false,
266 /*AllowDestructorName=*/false,
267 /*AllowConstructorName=*/false,
268 /*AllowDeductionGuide=*/false,
269 /*TemplateKWLoc=*/nullptr, Result)) {
270 SkipUntil(T: tok::semi);
271 return nullptr;
272 }
273
274 if (Result.getKind() != UnqualifiedIdKind::IK_Identifier) {
275 Diag(Loc: Result.getBeginLoc(), DiagID: diag::err_concept_definition_not_identifier);
276 SkipUntil(T: tok::semi);
277 return nullptr;
278 }
279
280 const IdentifierInfo *Id = Result.Identifier;
281 SourceLocation IdLoc = Result.getBeginLoc();
282
283 // [C++26][basic.scope.pdecl]/p13
284 // The locus of a concept-definition is immediately after its concept-name.
285 ConceptDecl *D = Actions.ActOnStartConceptDefinition(
286 S: getCurScope(), TemplateParameterLists: *TemplateInfo.TemplateParams, Name: Id, NameLoc: IdLoc);
287
288 ParsedAttributes Attrs(AttrFactory);
289 MaybeParseAttributes(WhichAttrKinds: PAKM_GNU | PAKM_CXX11, Attrs);
290
291 if (!TryConsumeToken(Expected: tok::equal)) {
292 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected) << tok::equal;
293 SkipUntil(T: tok::semi);
294 if (D)
295 D->setInvalidDecl();
296 return nullptr;
297 }
298
299 ExprResult ConstraintExprResult = ParseConstraintExpression();
300 if (ConstraintExprResult.isInvalid()) {
301 SkipUntil(T: tok::semi);
302 if (D)
303 D->setInvalidDecl();
304 return nullptr;
305 }
306
307 DeclEnd = Tok.getLocation();
308 ExpectAndConsumeSemi(DiagID: diag::err_expected_semi_declaration);
309 Expr *ConstraintExpr = ConstraintExprResult.get();
310
311 if (!D)
312 return nullptr;
313
314 return Actions.ActOnFinishConceptDefinition(S: getCurScope(), C: D, ConstraintExpr,
315 Attrs);
316}
317
318bool Parser::ParseTemplateParameters(
319 MultiParseScope &TemplateScopes, unsigned Depth,
320 SmallVectorImpl<NamedDecl *> &TemplateParams, SourceLocation &LAngleLoc,
321 SourceLocation &RAngleLoc) {
322 // Get the template parameter list.
323 if (!TryConsumeToken(Expected: tok::less, Loc&: LAngleLoc)) {
324 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected_less_after) << "template";
325 return true;
326 }
327
328 // Try to parse the template parameter list.
329 bool Failed = false;
330 // FIXME: Missing greatergreatergreater support.
331 if (!Tok.is(K: tok::greater) && !Tok.is(K: tok::greatergreater)) {
332 TemplateScopes.Enter(ScopeFlags: Scope::TemplateParamScope);
333 Failed = ParseTemplateParameterList(Depth, TemplateParams);
334 }
335
336 if (Tok.is(K: tok::greatergreater)) {
337 // No diagnostic required here: a template-parameter-list can only be
338 // followed by a declaration or, for a template template parameter, the
339 // 'class' keyword. Therefore, the second '>' will be diagnosed later.
340 // This matters for elegant diagnosis of:
341 // template<template<typename>> struct S;
342 Tok.setKind(tok::greater);
343 RAngleLoc = Tok.getLocation();
344 Tok.setLocation(Tok.getLocation().getLocWithOffset(Offset: 1));
345 } else if (!TryConsumeToken(Expected: tok::greater, Loc&: RAngleLoc) && Failed) {
346 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected) << tok::greater;
347 return true;
348 }
349 return false;
350}
351
352bool
353Parser::ParseTemplateParameterList(const unsigned Depth,
354 SmallVectorImpl<NamedDecl*> &TemplateParams) {
355 while (true) {
356
357 if (NamedDecl *TmpParam
358 = ParseTemplateParameter(Depth, Position: TemplateParams.size())) {
359 TemplateParams.push_back(Elt: TmpParam);
360 } else {
361 // If we failed to parse a template parameter, skip until we find
362 // a comma or closing brace.
363 SkipUntil(T1: tok::comma, T2: tok::greater, T3: tok::greatergreater,
364 Flags: StopAtSemi | StopBeforeMatch);
365 }
366
367 // Did we find a comma or the end of the template parameter list?
368 if (Tok.is(K: tok::comma)) {
369 ConsumeToken();
370 } else if (Tok.isOneOf(Ks: tok::greater, Ks: tok::greatergreater)) {
371 // Don't consume this... that's done by template parser.
372 break;
373 } else {
374 // Somebody probably forgot to close the template. Skip ahead and
375 // try to get out of the expression. This error is currently
376 // subsumed by whatever goes on in ParseTemplateParameter.
377 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected_comma_greater);
378 SkipUntil(T1: tok::comma, T2: tok::greater, T3: tok::greatergreater,
379 Flags: StopAtSemi | StopBeforeMatch);
380 return false;
381 }
382 }
383 return true;
384}
385
386Parser::TPResult Parser::isStartOfTemplateTypeParameter() {
387 if (Tok.is(K: tok::kw_class)) {
388 // "class" may be the start of an elaborated-type-specifier or a
389 // type-parameter. Per C++ [temp.param]p3, we prefer the type-parameter.
390 switch (NextToken().getKind()) {
391 case tok::equal:
392 case tok::comma:
393 case tok::greater:
394 case tok::greatergreater:
395 case tok::ellipsis:
396 return TPResult::True;
397
398 case tok::identifier:
399 // This may be either a type-parameter or an elaborated-type-specifier.
400 // We have to look further.
401 break;
402
403 default:
404 return TPResult::False;
405 }
406
407 switch (GetLookAheadToken(N: 2).getKind()) {
408 case tok::equal:
409 case tok::comma:
410 case tok::greater:
411 case tok::greatergreater:
412 return TPResult::True;
413
414 default:
415 return TPResult::False;
416 }
417 }
418
419 if (TryAnnotateTypeConstraint())
420 return TPResult::Error;
421
422 if (isTypeConstraintAnnotation() &&
423 // Next token might be 'auto' or 'decltype', indicating that this
424 // type-constraint is in fact part of a placeholder-type-specifier of a
425 // non-type template parameter.
426 !GetLookAheadToken(N: Tok.is(K: tok::annot_cxxscope) ? 2 : 1)
427 .isOneOf(Ks: tok::kw_auto, Ks: tok::kw_decltype))
428 return TPResult::True;
429
430 // 'typedef' is a reasonably-common typo/thinko for 'typename', and is
431 // ill-formed otherwise.
432 if (Tok.isNot(K: tok::kw_typename) && Tok.isNot(K: tok::kw_typedef))
433 return TPResult::False;
434
435 // C++ [temp.param]p2:
436 // There is no semantic difference between class and typename in a
437 // template-parameter. typename followed by an unqualified-id
438 // names a template type parameter. typename followed by a
439 // qualified-id denotes the type in a non-type
440 // parameter-declaration.
441 Token Next = NextToken();
442
443 // If we have an identifier, skip over it.
444 if (Next.getKind() == tok::identifier)
445 Next = GetLookAheadToken(N: 2);
446
447 switch (Next.getKind()) {
448 case tok::equal:
449 case tok::comma:
450 case tok::greater:
451 case tok::greatergreater:
452 case tok::ellipsis:
453 return TPResult::True;
454
455 case tok::kw_typename:
456 case tok::kw_typedef:
457 case tok::kw_class:
458 // These indicate that a comma was missed after a type parameter, not that
459 // we have found a non-type parameter.
460 return TPResult::True;
461
462 default:
463 return TPResult::False;
464 }
465}
466
467NamedDecl *Parser::ParseTemplateParameter(unsigned Depth, unsigned Position) {
468
469 switch (isStartOfTemplateTypeParameter()) {
470 case TPResult::True:
471 // Is there just a typo in the input code? ('typedef' instead of
472 // 'typename')
473 if (Tok.is(K: tok::kw_typedef)) {
474 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected_template_parameter);
475
476 Diag(Loc: Tok.getLocation(), DiagID: diag::note_meant_to_use_typename)
477 << FixItHint::CreateReplacement(RemoveRange: CharSourceRange::getCharRange(
478 B: Tok.getLocation(),
479 E: Tok.getEndLoc()),
480 Code: "typename");
481
482 Tok.setKind(tok::kw_typename);
483 }
484
485 return ParseTypeParameter(Depth, Position);
486 case TPResult::False:
487 break;
488
489 case TPResult::Error: {
490 // We return an invalid parameter as opposed to null to avoid having bogus
491 // diagnostics about an empty template parameter list.
492 // FIXME: Fix ParseTemplateParameterList to better handle nullptr results
493 // from here.
494 // Return a NTTP as if there was an error in a scope specifier, the user
495 // probably meant to write the type of a NTTP.
496 DeclSpec DS(getAttrFactory());
497 DS.SetTypeSpecError();
498 Declarator D(DS, ParsedAttributesView::none(),
499 DeclaratorContext::TemplateParam);
500 D.SetIdentifier(Id: nullptr, IdLoc: Tok.getLocation());
501 D.setInvalidType(true);
502 NamedDecl *ErrorParam = Actions.ActOnNonTypeTemplateParameter(
503 S: getCurScope(), D, Depth, Position, /*EqualLoc=*/SourceLocation(),
504 /*DefaultArg=*/nullptr);
505 ErrorParam->setInvalidDecl(true);
506 SkipUntil(T1: tok::comma, T2: tok::greater, T3: tok::greatergreater,
507 Flags: StopAtSemi | StopBeforeMatch);
508 return ErrorParam;
509 }
510
511 case TPResult::Ambiguous:
512 llvm_unreachable("template param classification can't be ambiguous");
513 }
514
515 if (Tok.is(K: tok::kw_template))
516 return ParseTemplateTemplateParameter(Depth, Position);
517
518 // If it's none of the above, then it must be a parameter declaration.
519 // NOTE: This will pick up errors in the closure of the template parameter
520 // list (e.g., template < ; Check here to implement >> style closures.
521 return ParseNonTypeTemplateParameter(Depth, Position);
522}
523
524bool Parser::isTypeConstraintAnnotation() {
525 const Token &T = Tok.is(K: tok::annot_cxxscope) ? NextToken() : Tok;
526 if (T.isNot(K: tok::annot_template_id))
527 return false;
528 const auto *ExistingAnnot =
529 static_cast<TemplateIdAnnotation *>(T.getAnnotationValue());
530 return ExistingAnnot->Kind == TNK_Concept_template;
531}
532
533bool Parser::TryAnnotateTypeConstraint() {
534 if (!getLangOpts().CPlusPlus20)
535 return false;
536 CXXScopeSpec SS;
537 bool WasScopeAnnotation = Tok.is(K: tok::annot_cxxscope);
538 if (ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
539 /*ObjectHasErrors=*/false,
540 /*EnteringContext=*/false,
541 /*MayBePseudoDestructor=*/nullptr,
542 // If this is not a type-constraint, then
543 // this scope-spec is part of the typename
544 // of a non-type template parameter
545 /*IsTypename=*/true, /*LastII=*/nullptr,
546 // We won't find concepts in
547 // non-namespaces anyway, so might as well
548 // parse this correctly for possible type
549 // names.
550 /*OnlyNamespace=*/false))
551 return true;
552
553 if (Tok.is(K: tok::identifier)) {
554 UnqualifiedId PossibleConceptName;
555 PossibleConceptName.setIdentifier(Id: Tok.getIdentifierInfo(),
556 IdLoc: Tok.getLocation());
557
558 TemplateTy PossibleConcept;
559 bool MemberOfUnknownSpecialization = false;
560 auto TNK = Actions.isTemplateName(S: getCurScope(), SS,
561 /*hasTemplateKeyword=*/false,
562 Name: PossibleConceptName,
563 /*ObjectType=*/ParsedType(),
564 /*EnteringContext=*/false,
565 Template&: PossibleConcept,
566 MemberOfUnknownSpecialization,
567 /*Disambiguation=*/true);
568 if (MemberOfUnknownSpecialization || !PossibleConcept ||
569 TNK != TNK_Concept_template) {
570 if (SS.isNotEmpty())
571 AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
572 return false;
573 }
574
575 // At this point we're sure we're dealing with a constrained parameter. It
576 // may or may not have a template parameter list following the concept
577 // name.
578 if (AnnotateTemplateIdToken(Template: PossibleConcept, TNK, SS,
579 /*TemplateKWLoc=*/SourceLocation(),
580 TemplateName&: PossibleConceptName,
581 /*AllowTypeAnnotation=*/false,
582 /*TypeConstraint=*/true))
583 return true;
584 }
585
586 if (SS.isNotEmpty())
587 AnnotateScopeToken(SS, IsNewAnnotation: !WasScopeAnnotation);
588 return false;
589}
590
591NamedDecl *Parser::ParseTypeParameter(unsigned Depth, unsigned Position) {
592 assert((Tok.isOneOf(tok::kw_class, tok::kw_typename) ||
593 isTypeConstraintAnnotation()) &&
594 "A type-parameter starts with 'class', 'typename' or a "
595 "type-constraint");
596
597 CXXScopeSpec TypeConstraintSS;
598 TemplateIdAnnotation *TypeConstraint = nullptr;
599 bool TypenameKeyword = false;
600 SourceLocation KeyLoc;
601 ParseOptionalCXXScopeSpecifier(SS&: TypeConstraintSS, /*ObjectType=*/nullptr,
602 /*ObjectHasErrors=*/false,
603 /*EnteringContext*/ false);
604 if (Tok.is(K: tok::annot_template_id)) {
605 // Consume the 'type-constraint'.
606 TypeConstraint =
607 static_cast<TemplateIdAnnotation *>(Tok.getAnnotationValue());
608 assert(TypeConstraint->Kind == TNK_Concept_template &&
609 "stray non-concept template-id annotation");
610 KeyLoc = ConsumeAnnotationToken();
611 } else {
612 assert(TypeConstraintSS.isEmpty() &&
613 "expected type constraint after scope specifier");
614
615 // Consume the 'class' or 'typename' keyword.
616 TypenameKeyword = Tok.is(K: tok::kw_typename);
617 KeyLoc = ConsumeToken();
618 }
619
620 // Grab the ellipsis (if given).
621 SourceLocation EllipsisLoc;
622 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc)) {
623 Diag(Loc: EllipsisLoc,
624 DiagID: getLangOpts().CPlusPlus11
625 ? diag::warn_cxx98_compat_variadic_templates
626 : diag::ext_variadic_templates);
627 }
628
629 // Grab the template parameter name (if given)
630 SourceLocation NameLoc = Tok.getLocation();
631 IdentifierInfo *ParamName = nullptr;
632 if (Tok.is(K: tok::identifier)) {
633 ParamName = Tok.getIdentifierInfo();
634 ConsumeToken();
635 } else if (Tok.isOneOf(Ks: tok::equal, Ks: tok::comma, Ks: tok::greater,
636 Ks: tok::greatergreater)) {
637 // Unnamed template parameter. Don't have to do anything here, just
638 // don't consume this token.
639 } else {
640 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected) << tok::identifier;
641 return nullptr;
642 }
643
644 // Recover from misplaced ellipsis.
645 bool AlreadyHasEllipsis = EllipsisLoc.isValid();
646 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc))
647 DiagnoseMisplacedEllipsis(EllipsisLoc, CorrectLoc: NameLoc, AlreadyHasEllipsis, IdentifierHasName: true);
648
649 // Grab a default argument (if available).
650 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
651 // we introduce the type parameter into the local scope.
652 SourceLocation EqualLoc;
653 ParsedType DefaultArg;
654 std::optional<DelayTemplateIdDestructionRAII> DontDestructTemplateIds;
655 if (TryConsumeToken(Expected: tok::equal, Loc&: EqualLoc)) {
656 // The default argument might contain a lambda declaration; avoid destroying
657 // parsed template ids at the end of that declaration because they can be
658 // used in a type constraint later.
659 DontDestructTemplateIds.emplace(args&: *this, /*DelayTemplateIdDestruction=*/args: true);
660 // The default argument may declare template parameters, notably
661 // if it contains a generic lambda, so we need to increase
662 // the template depth as these parameters would not be instantiated
663 // at the current level.
664 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
665 ++CurTemplateDepthTracker;
666 DefaultArg =
667 ParseTypeName(/*Range=*/nullptr, Context: DeclaratorContext::TemplateTypeArg)
668 .get();
669 }
670
671 NamedDecl *NewDecl = Actions.ActOnTypeParameter(S: getCurScope(),
672 Typename: TypenameKeyword, EllipsisLoc,
673 KeyLoc, ParamName, ParamNameLoc: NameLoc,
674 Depth, Position, EqualLoc,
675 DefaultArg,
676 HasTypeConstraint: TypeConstraint != nullptr);
677
678 if (TypeConstraint) {
679 Actions.ActOnTypeConstraint(SS: TypeConstraintSS, TypeConstraint,
680 ConstrainedParameter: cast<TemplateTypeParmDecl>(Val: NewDecl),
681 EllipsisLoc);
682 }
683
684 return NewDecl;
685}
686
687NamedDecl *Parser::ParseTemplateTemplateParameter(unsigned Depth,
688 unsigned Position) {
689 assert(Tok.is(tok::kw_template) && "Expected 'template' keyword");
690
691 // Handle the template <...> part.
692 SourceLocation TemplateLoc = ConsumeToken();
693 SmallVector<NamedDecl*,8> TemplateParams;
694 SourceLocation LAngleLoc, RAngleLoc;
695 ExprResult OptionalRequiresClauseConstraintER;
696 {
697 MultiParseScope TemplateParmScope(*this);
698 if (ParseTemplateParameters(TemplateScopes&: TemplateParmScope, Depth: Depth + 1, TemplateParams,
699 LAngleLoc, RAngleLoc)) {
700 return nullptr;
701 }
702 if (TryConsumeToken(Expected: tok::kw_requires)) {
703 OptionalRequiresClauseConstraintER =
704 Actions.ActOnRequiresClause(ConstraintExpr: ParseConstraintLogicalOrExpression(
705 /*IsTrailingRequiresClause=*/false));
706 if (!OptionalRequiresClauseConstraintER.isUsable()) {
707 SkipUntil(T1: tok::comma, T2: tok::greater, T3: tok::greatergreater,
708 Flags: StopAtSemi | StopBeforeMatch);
709 return nullptr;
710 }
711 }
712 }
713
714 // Provide an ExtWarn if the C++1z feature of using 'typename' here is used.
715 // Generate a meaningful error if the user forgot to put class before the
716 // identifier, comma, or greater. Provide a fixit if the identifier, comma,
717 // or greater appear immediately or after 'struct'. In the latter case,
718 // replace the keyword with 'class'.
719 bool TypenameKeyword = false;
720 if (!TryConsumeToken(Expected: tok::kw_class)) {
721 bool Replace = Tok.isOneOf(Ks: tok::kw_typename, Ks: tok::kw_struct);
722 const Token &Next = Tok.is(K: tok::kw_struct) ? NextToken() : Tok;
723 if (Tok.is(K: tok::kw_typename)) {
724 TypenameKeyword = true;
725 Diag(Loc: Tok.getLocation(),
726 DiagID: getLangOpts().CPlusPlus17
727 ? diag::warn_cxx14_compat_template_template_param_typename
728 : diag::ext_template_template_param_typename)
729 << (!getLangOpts().CPlusPlus17
730 ? FixItHint::CreateReplacement(RemoveRange: Tok.getLocation(), Code: "class")
731 : FixItHint());
732 } else if (Next.isOneOf(Ks: tok::identifier, Ks: tok::comma, Ks: tok::greater,
733 Ks: tok::greatergreater, Ks: tok::ellipsis)) {
734 Diag(Loc: Tok.getLocation(), DiagID: diag::err_class_on_template_template_param)
735 << getLangOpts().CPlusPlus17
736 << (Replace
737 ? FixItHint::CreateReplacement(RemoveRange: Tok.getLocation(), Code: "class")
738 : FixItHint::CreateInsertion(InsertionLoc: Tok.getLocation(), Code: "class "));
739 } else
740 Diag(Loc: Tok.getLocation(), DiagID: diag::err_class_on_template_template_param)
741 << getLangOpts().CPlusPlus17;
742
743 if (Replace)
744 ConsumeToken();
745 }
746
747 // Parse the ellipsis, if given.
748 SourceLocation EllipsisLoc;
749 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc))
750 Diag(Loc: EllipsisLoc,
751 DiagID: getLangOpts().CPlusPlus11
752 ? diag::warn_cxx98_compat_variadic_templates
753 : diag::ext_variadic_templates);
754
755 // Get the identifier, if given.
756 SourceLocation NameLoc = Tok.getLocation();
757 IdentifierInfo *ParamName = nullptr;
758 if (Tok.is(K: tok::identifier)) {
759 ParamName = Tok.getIdentifierInfo();
760 ConsumeToken();
761 } else if (Tok.isOneOf(Ks: tok::equal, Ks: tok::comma, Ks: tok::greater,
762 Ks: tok::greatergreater)) {
763 // Unnamed template parameter. Don't have to do anything here, just
764 // don't consume this token.
765 } else {
766 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected) << tok::identifier;
767 return nullptr;
768 }
769
770 // Recover from misplaced ellipsis.
771 bool AlreadyHasEllipsis = EllipsisLoc.isValid();
772 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc))
773 DiagnoseMisplacedEllipsis(EllipsisLoc, CorrectLoc: NameLoc, AlreadyHasEllipsis, IdentifierHasName: true);
774
775 TemplateParameterList *ParamList = Actions.ActOnTemplateParameterList(
776 Depth, ExportLoc: SourceLocation(), TemplateLoc, LAngleLoc, Params: TemplateParams,
777 RAngleLoc, RequiresClause: OptionalRequiresClauseConstraintER.get());
778
779 // Grab a default argument (if available).
780 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
781 // we introduce the template parameter into the local scope.
782 SourceLocation EqualLoc;
783 ParsedTemplateArgument DefaultArg;
784 if (TryConsumeToken(Expected: tok::equal, Loc&: EqualLoc)) {
785 DefaultArg = ParseTemplateTemplateArgument();
786 if (DefaultArg.isInvalid()) {
787 Diag(Loc: Tok.getLocation(),
788 DiagID: diag::err_default_template_template_parameter_not_template);
789 SkipUntil(T1: tok::comma, T2: tok::greater, T3: tok::greatergreater,
790 Flags: StopAtSemi | StopBeforeMatch);
791 }
792 }
793
794 return Actions.ActOnTemplateTemplateParameter(
795 S: getCurScope(), TmpLoc: TemplateLoc, Params: ParamList, Typename: TypenameKeyword, EllipsisLoc,
796 ParamName, ParamNameLoc: NameLoc, Depth, Position, EqualLoc, DefaultArg);
797}
798
799NamedDecl *
800Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) {
801 // Parse the declaration-specifiers (i.e., the type).
802 // FIXME: The type should probably be restricted in some way... Not all
803 // declarators (parts of declarators?) are accepted for parameters.
804 DeclSpec DS(AttrFactory);
805 ParsedTemplateInfo TemplateInfo;
806 ParseDeclarationSpecifiers(DS, TemplateInfo, AS: AS_none,
807 DSC: DeclSpecContext::DSC_template_param);
808
809 // Parse this as a typename.
810 Declarator ParamDecl(DS, ParsedAttributesView::none(),
811 DeclaratorContext::TemplateParam);
812 ParseDeclarator(D&: ParamDecl);
813 if (DS.getTypeSpecType() == DeclSpec::TST_unspecified) {
814 Diag(Loc: Tok.getLocation(), DiagID: diag::err_expected_template_parameter);
815 return nullptr;
816 }
817
818 // Recover from misplaced ellipsis.
819 SourceLocation EllipsisLoc;
820 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc))
821 DiagnoseMisplacedEllipsisInDeclarator(EllipsisLoc, D&: ParamDecl);
822
823 // If there is a default value, parse it.
824 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
825 // we introduce the template parameter into the local scope.
826 SourceLocation EqualLoc;
827 ExprResult DefaultArg;
828 if (TryConsumeToken(Expected: tok::equal, Loc&: EqualLoc)) {
829 if (Tok.is(K: tok::l_paren) && NextToken().is(K: tok::l_brace)) {
830 Diag(Loc: Tok.getLocation(), DiagID: diag::err_stmt_expr_in_default_arg) << 1;
831 SkipUntil(T1: tok::comma, T2: tok::greater, Flags: StopAtSemi | StopBeforeMatch);
832 } else {
833 // C++ [temp.param]p15:
834 // When parsing a default template-argument for a non-type
835 // template-parameter, the first non-nested > is taken as the
836 // end of the template-parameter-list rather than a greater-than
837 // operator.
838 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false);
839
840 // The default argument may declare template parameters, notably
841 // if it contains a generic lambda, so we need to increase
842 // the template depth as these parameters would not be instantiated
843 // at the current level.
844 TemplateParameterDepthRAII CurTemplateDepthTracker(
845 TemplateParameterDepth);
846 ++CurTemplateDepthTracker;
847 EnterExpressionEvaluationContext ConstantEvaluated(
848 Actions, Sema::ExpressionEvaluationContext::ConstantEvaluated);
849 DefaultArg = Actions.ActOnConstantExpression(Res: ParseInitializer());
850 if (DefaultArg.isInvalid())
851 SkipUntil(T1: tok::comma, T2: tok::greater, Flags: StopAtSemi | StopBeforeMatch);
852 }
853 }
854
855 // Create the parameter.
856 return Actions.ActOnNonTypeTemplateParameter(S: getCurScope(), D&: ParamDecl,
857 Depth, Position, EqualLoc,
858 DefaultArg: DefaultArg.get());
859}
860
861void Parser::DiagnoseMisplacedEllipsis(SourceLocation EllipsisLoc,
862 SourceLocation CorrectLoc,
863 bool AlreadyHasEllipsis,
864 bool IdentifierHasName) {
865 FixItHint Insertion;
866 if (!AlreadyHasEllipsis)
867 Insertion = FixItHint::CreateInsertion(InsertionLoc: CorrectLoc, Code: "...");
868 Diag(Loc: EllipsisLoc, DiagID: diag::err_misplaced_ellipsis_in_declaration)
869 << FixItHint::CreateRemoval(RemoveRange: EllipsisLoc) << Insertion
870 << !IdentifierHasName;
871}
872
873void Parser::DiagnoseMisplacedEllipsisInDeclarator(SourceLocation EllipsisLoc,
874 Declarator &D) {
875 assert(EllipsisLoc.isValid());
876 bool AlreadyHasEllipsis = D.getEllipsisLoc().isValid();
877 if (!AlreadyHasEllipsis)
878 D.setEllipsisLoc(EllipsisLoc);
879 DiagnoseMisplacedEllipsis(EllipsisLoc, CorrectLoc: D.getIdentifierLoc(),
880 AlreadyHasEllipsis, IdentifierHasName: D.hasName());
881}
882
883bool Parser::ParseGreaterThanInTemplateList(SourceLocation LAngleLoc,
884 SourceLocation &RAngleLoc,
885 bool ConsumeLastToken,
886 bool ObjCGenericList) {
887 // What will be left once we've consumed the '>'.
888 tok::TokenKind RemainingToken;
889 const char *ReplacementStr = "> >";
890 bool MergeWithNextToken = false;
891
892 switch (Tok.getKind()) {
893 default:
894 Diag(Loc: getEndOfPreviousToken(), DiagID: diag::err_expected) << tok::greater;
895 Diag(Loc: LAngleLoc, DiagID: diag::note_matching) << tok::less;
896 return true;
897
898 case tok::greater:
899 // Determine the location of the '>' token. Only consume this token
900 // if the caller asked us to.
901 RAngleLoc = Tok.getLocation();
902 if (ConsumeLastToken)
903 ConsumeToken();
904 return false;
905
906 case tok::greatergreater:
907 RemainingToken = tok::greater;
908 break;
909
910 case tok::greatergreatergreater:
911 RemainingToken = tok::greatergreater;
912 break;
913
914 case tok::greaterequal:
915 RemainingToken = tok::equal;
916 ReplacementStr = "> =";
917
918 // Join two adjacent '=' tokens into one, for cases like:
919 // void (*p)() = f<int>;
920 // return f<int>==p;
921 if (NextToken().is(K: tok::equal) &&
922 areTokensAdjacent(A: Tok, B: NextToken())) {
923 RemainingToken = tok::equalequal;
924 MergeWithNextToken = true;
925 }
926 break;
927
928 case tok::greatergreaterequal:
929 RemainingToken = tok::greaterequal;
930 break;
931 }
932
933 // This template-id is terminated by a token that starts with a '>'.
934 // Outside C++11 and Objective-C, this is now error recovery.
935 //
936 // C++11 allows this when the token is '>>', and in CUDA + C++11 mode, we
937 // extend that treatment to also apply to the '>>>' token.
938 //
939 // Objective-C allows this in its type parameter / argument lists.
940
941 SourceLocation TokBeforeGreaterLoc = PrevTokLocation;
942 SourceLocation TokLoc = Tok.getLocation();
943 Token Next = NextToken();
944
945 // Whether splitting the current token after the '>' would undesirably result
946 // in the remaining token pasting with the token after it. This excludes the
947 // MergeWithNextToken cases, which we've already handled.
948 bool PreventMergeWithNextToken =
949 (RemainingToken == tok::greater ||
950 RemainingToken == tok::greatergreater) &&
951 (Next.isOneOf(Ks: tok::greater, Ks: tok::greatergreater,
952 Ks: tok::greatergreatergreater, Ks: tok::equal, Ks: tok::greaterequal,
953 Ks: tok::greatergreaterequal, Ks: tok::equalequal)) &&
954 areTokensAdjacent(A: Tok, B: Next);
955
956 // Diagnose this situation as appropriate.
957 if (!ObjCGenericList) {
958 // The source range of the replaced token(s).
959 CharSourceRange ReplacementRange = CharSourceRange::getCharRange(
960 B: TokLoc, E: Lexer::AdvanceToTokenCharacter(TokStart: TokLoc, Characters: 2, SM: PP.getSourceManager(),
961 LangOpts: getLangOpts()));
962
963 // A hint to put a space between the '>>'s. In order to make the hint as
964 // clear as possible, we include the characters either side of the space in
965 // the replacement, rather than just inserting a space at SecondCharLoc.
966 FixItHint Hint1 = FixItHint::CreateReplacement(RemoveRange: ReplacementRange,
967 Code: ReplacementStr);
968
969 // A hint to put another space after the token, if it would otherwise be
970 // lexed differently.
971 FixItHint Hint2;
972 if (PreventMergeWithNextToken)
973 Hint2 = FixItHint::CreateInsertion(InsertionLoc: Next.getLocation(), Code: " ");
974
975 unsigned DiagId = diag::err_two_right_angle_brackets_need_space;
976 if (getLangOpts().CPlusPlus11 &&
977 (Tok.is(K: tok::greatergreater) || Tok.is(K: tok::greatergreatergreater)))
978 DiagId = diag::warn_cxx98_compat_two_right_angle_brackets;
979 else if (Tok.is(K: tok::greaterequal))
980 DiagId = diag::err_right_angle_bracket_equal_needs_space;
981 Diag(Loc: TokLoc, DiagID: DiagId) << Hint1 << Hint2;
982 }
983
984 // Find the "length" of the resulting '>' token. This is not always 1, as it
985 // can contain escaped newlines.
986 unsigned GreaterLength = Lexer::getTokenPrefixLength(
987 TokStart: TokLoc, CharNo: 1, SM: PP.getSourceManager(), LangOpts: getLangOpts());
988
989 // Annotate the source buffer to indicate that we split the token after the
990 // '>'. This allows us to properly find the end of, and extract the spelling
991 // of, the '>' token later.
992 RAngleLoc = PP.SplitToken(TokLoc, Length: GreaterLength);
993
994 // Strip the initial '>' from the token.
995 bool CachingTokens = PP.IsPreviousCachedToken(Tok);
996
997 Token Greater = Tok;
998 Greater.setLocation(RAngleLoc);
999 Greater.setKind(tok::greater);
1000 Greater.setLength(GreaterLength);
1001
1002 unsigned OldLength = Tok.getLength();
1003 if (MergeWithNextToken) {
1004 ConsumeToken();
1005 OldLength += Tok.getLength();
1006 }
1007
1008 Tok.setKind(RemainingToken);
1009 Tok.setLength(OldLength - GreaterLength);
1010
1011 // Split the second token if lexing it normally would lex a different token
1012 // (eg, the fifth token in 'A<B>>>' should re-lex as '>', not '>>').
1013 SourceLocation AfterGreaterLoc = TokLoc.getLocWithOffset(Offset: GreaterLength);
1014 if (PreventMergeWithNextToken)
1015 AfterGreaterLoc = PP.SplitToken(TokLoc: AfterGreaterLoc, Length: Tok.getLength());
1016 Tok.setLocation(AfterGreaterLoc);
1017
1018 // Update the token cache to match what we just did if necessary.
1019 if (CachingTokens) {
1020 // If the previous cached token is being merged, delete it.
1021 if (MergeWithNextToken)
1022 PP.ReplacePreviousCachedToken(NewToks: {});
1023
1024 if (ConsumeLastToken)
1025 PP.ReplacePreviousCachedToken(NewToks: {Greater, Tok});
1026 else
1027 PP.ReplacePreviousCachedToken(NewToks: {Greater});
1028 }
1029
1030 if (ConsumeLastToken) {
1031 PrevTokLocation = RAngleLoc;
1032 } else {
1033 PrevTokLocation = TokBeforeGreaterLoc;
1034 PP.EnterToken(Tok, /*IsReinject=*/true);
1035 Tok = Greater;
1036 }
1037
1038 return false;
1039}
1040
1041bool Parser::ParseTemplateIdAfterTemplateName(bool ConsumeLastToken,
1042 SourceLocation &LAngleLoc,
1043 TemplateArgList &TemplateArgs,
1044 SourceLocation &RAngleLoc,
1045 TemplateTy Template) {
1046 assert(Tok.is(tok::less) && "Must have already parsed the template-name");
1047
1048 // Consume the '<'.
1049 LAngleLoc = ConsumeToken();
1050
1051 // Parse the optional template-argument-list.
1052 bool Invalid = false;
1053 {
1054 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false);
1055 if (!Tok.isOneOf(Ks: tok::greater, Ks: tok::greatergreater,
1056 Ks: tok::greatergreatergreater, Ks: tok::greaterequal,
1057 Ks: tok::greatergreaterequal))
1058 Invalid = ParseTemplateArgumentList(TemplateArgs, Template, OpenLoc: LAngleLoc);
1059
1060 if (Invalid) {
1061 // Try to find the closing '>'.
1062 if (getLangOpts().CPlusPlus11)
1063 SkipUntil(T1: tok::greater, T2: tok::greatergreater,
1064 T3: tok::greatergreatergreater, Flags: StopAtSemi | StopBeforeMatch);
1065 else
1066 SkipUntil(T: tok::greater, Flags: StopAtSemi | StopBeforeMatch);
1067 }
1068 }
1069
1070 return ParseGreaterThanInTemplateList(LAngleLoc, RAngleLoc, ConsumeLastToken,
1071 /*ObjCGenericList=*/false) ||
1072 Invalid;
1073}
1074
1075bool Parser::AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK,
1076 CXXScopeSpec &SS,
1077 SourceLocation TemplateKWLoc,
1078 UnqualifiedId &TemplateName,
1079 bool AllowTypeAnnotation,
1080 bool TypeConstraint) {
1081 assert(getLangOpts().CPlusPlus && "Can only annotate template-ids in C++");
1082 assert((Tok.is(tok::less) || TypeConstraint) &&
1083 "Parser isn't at the beginning of a template-id");
1084 assert(!(TypeConstraint && AllowTypeAnnotation) && "type-constraint can't be "
1085 "a type annotation");
1086 assert((!TypeConstraint || TNK == TNK_Concept_template) && "type-constraint "
1087 "must accompany a concept name");
1088 assert((Template || TNK == TNK_Non_template) && "missing template name");
1089
1090 // Consume the template-name.
1091 SourceLocation TemplateNameLoc = TemplateName.getSourceRange().getBegin();
1092
1093 // Parse the enclosed template argument list.
1094 SourceLocation LAngleLoc, RAngleLoc;
1095 TemplateArgList TemplateArgs;
1096 bool ArgsInvalid = false;
1097 if (!TypeConstraint || Tok.is(K: tok::less)) {
1098 ArgsInvalid = ParseTemplateIdAfterTemplateName(
1099 ConsumeLastToken: false, LAngleLoc, TemplateArgs, RAngleLoc, Template);
1100 // If we couldn't recover from invalid arguments, don't form an annotation
1101 // token -- we don't know how much to annotate.
1102 // FIXME: This can lead to duplicate diagnostics if we retry parsing this
1103 // template-id in another context. Try to annotate anyway?
1104 if (RAngleLoc.isInvalid())
1105 return true;
1106 }
1107
1108 ASTTemplateArgsPtr TemplateArgsPtr(TemplateArgs);
1109
1110 // Build the annotation token.
1111 if (TNK == TNK_Type_template && AllowTypeAnnotation) {
1112 TypeResult Type = ArgsInvalid
1113 ? TypeError()
1114 : Actions.ActOnTemplateIdType(
1115 S: getCurScope(), SS, TemplateKWLoc, Template,
1116 TemplateII: TemplateName.Identifier, TemplateIILoc: TemplateNameLoc,
1117 LAngleLoc, TemplateArgs: TemplateArgsPtr, RAngleLoc);
1118
1119 Tok.setKind(tok::annot_typename);
1120 setTypeAnnotation(Tok, T: Type);
1121 if (SS.isNotEmpty())
1122 Tok.setLocation(SS.getBeginLoc());
1123 else if (TemplateKWLoc.isValid())
1124 Tok.setLocation(TemplateKWLoc);
1125 else
1126 Tok.setLocation(TemplateNameLoc);
1127 } else {
1128 // Build a template-id annotation token that can be processed
1129 // later.
1130 Tok.setKind(tok::annot_template_id);
1131
1132 const IdentifierInfo *TemplateII =
1133 TemplateName.getKind() == UnqualifiedIdKind::IK_Identifier
1134 ? TemplateName.Identifier
1135 : nullptr;
1136
1137 OverloadedOperatorKind OpKind =
1138 TemplateName.getKind() == UnqualifiedIdKind::IK_Identifier
1139 ? OO_None
1140 : TemplateName.OperatorFunctionId.Operator;
1141
1142 TemplateIdAnnotation *TemplateId = TemplateIdAnnotation::Create(
1143 TemplateKWLoc, TemplateNameLoc, Name: TemplateII, OperatorKind: OpKind, OpaqueTemplateName: Template, TemplateKind: TNK,
1144 LAngleLoc, RAngleLoc, TemplateArgs, ArgsInvalid, CleanupList&: TemplateIds);
1145
1146 Tok.setAnnotationValue(TemplateId);
1147 if (TemplateKWLoc.isValid())
1148 Tok.setLocation(TemplateKWLoc);
1149 else
1150 Tok.setLocation(TemplateNameLoc);
1151 }
1152
1153 // Common fields for the annotation token
1154 Tok.setAnnotationEndLoc(RAngleLoc);
1155
1156 // In case the tokens were cached, have Preprocessor replace them with the
1157 // annotation token.
1158 PP.AnnotateCachedTokens(Tok);
1159 return false;
1160}
1161
1162void Parser::AnnotateTemplateIdTokenAsType(
1163 CXXScopeSpec &SS, ImplicitTypenameContext AllowImplicitTypename,
1164 bool IsClassName) {
1165 assert(Tok.is(tok::annot_template_id) && "Requires template-id tokens");
1166
1167 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(tok: Tok);
1168 assert(TemplateId->mightBeType() &&
1169 "Only works for type and dependent templates");
1170
1171 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
1172 TemplateId->NumArgs);
1173
1174 TypeResult Type =
1175 TemplateId->isInvalid()
1176 ? TypeError()
1177 : Actions.ActOnTemplateIdType(
1178 S: getCurScope(), SS, TemplateKWLoc: TemplateId->TemplateKWLoc,
1179 Template: TemplateId->Template, TemplateII: TemplateId->Name,
1180 TemplateIILoc: TemplateId->TemplateNameLoc, LAngleLoc: TemplateId->LAngleLoc,
1181 TemplateArgs: TemplateArgsPtr, RAngleLoc: TemplateId->RAngleLoc,
1182 /*IsCtorOrDtorName=*/false, IsClassName, AllowImplicitTypename);
1183 // Create the new "type" annotation token.
1184 Tok.setKind(tok::annot_typename);
1185 setTypeAnnotation(Tok, T: Type);
1186 if (SS.isNotEmpty()) // it was a C++ qualified type name.
1187 Tok.setLocation(SS.getBeginLoc());
1188 // End location stays the same
1189
1190 // Replace the template-id annotation token, and possible the scope-specifier
1191 // that precedes it, with the typename annotation token.
1192 PP.AnnotateCachedTokens(Tok);
1193}
1194
1195/// Determine whether the given token can end a template argument.
1196static bool isEndOfTemplateArgument(Token Tok) {
1197 // FIXME: Handle '>>>'.
1198 return Tok.isOneOf(Ks: tok::comma, Ks: tok::greater, Ks: tok::greatergreater,
1199 Ks: tok::greatergreatergreater);
1200}
1201
1202ParsedTemplateArgument Parser::ParseTemplateTemplateArgument() {
1203 if (!Tok.is(K: tok::identifier) && !Tok.is(K: tok::coloncolon) &&
1204 !Tok.is(K: tok::annot_cxxscope))
1205 return ParsedTemplateArgument();
1206
1207 // C++0x [temp.arg.template]p1:
1208 // A template-argument for a template template-parameter shall be the name
1209 // of a class template or an alias template, expressed as id-expression.
1210 //
1211 // We parse an id-expression that refers to a class template or alias
1212 // template. The grammar we parse is:
1213 //
1214 // nested-name-specifier[opt] template[opt] identifier ...[opt]
1215 //
1216 // followed by a token that terminates a template argument, such as ',',
1217 // '>', or (in some cases) '>>'.
1218 CXXScopeSpec SS; // nested-name-specifier, if present
1219 ParseOptionalCXXScopeSpecifier(SS, /*ObjectType=*/nullptr,
1220 /*ObjectHasErrors=*/false,
1221 /*EnteringContext=*/false);
1222
1223 ParsedTemplateArgument Result;
1224 SourceLocation EllipsisLoc;
1225 if (SS.isSet() && Tok.is(K: tok::kw_template)) {
1226 // Parse the optional 'template' keyword following the
1227 // nested-name-specifier.
1228 SourceLocation TemplateKWLoc = ConsumeToken();
1229
1230 if (Tok.is(K: tok::identifier)) {
1231 // We appear to have a dependent template name.
1232 UnqualifiedId Name;
1233 Name.setIdentifier(Id: Tok.getIdentifierInfo(), IdLoc: Tok.getLocation());
1234 ConsumeToken(); // the identifier
1235
1236 TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc);
1237
1238 // If the next token signals the end of a template argument, then we have
1239 // a (possibly-dependent) template name that could be a template template
1240 // argument.
1241 TemplateTy Template;
1242 if (isEndOfTemplateArgument(Tok) &&
1243 Actions.ActOnTemplateName(S: getCurScope(), SS, TemplateKWLoc, Name,
1244 /*ObjectType=*/nullptr,
1245 /*EnteringContext=*/false, Template))
1246 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation);
1247 }
1248 } else if (Tok.is(K: tok::identifier)) {
1249 // We may have a (non-dependent) template name.
1250 TemplateTy Template;
1251 UnqualifiedId Name;
1252 Name.setIdentifier(Id: Tok.getIdentifierInfo(), IdLoc: Tok.getLocation());
1253 ConsumeToken(); // the identifier
1254
1255 TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc);
1256
1257 if (isEndOfTemplateArgument(Tok)) {
1258 bool MemberOfUnknownSpecialization;
1259 TemplateNameKind TNK = Actions.isTemplateName(
1260 S: getCurScope(), SS,
1261 /*hasTemplateKeyword=*/false, Name,
1262 /*ObjectType=*/nullptr,
1263 /*EnteringContext=*/false, Template, MemberOfUnknownSpecialization);
1264 if (TNK == TNK_Dependent_template_name || TNK == TNK_Type_template) {
1265 // We have an id-expression that refers to a class template or
1266 // (C++0x) alias template.
1267 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation);
1268 }
1269 }
1270 }
1271
1272 // If this is a pack expansion, build it as such.
1273 if (EllipsisLoc.isValid() && !Result.isInvalid())
1274 Result = Actions.ActOnPackExpansion(Arg: Result, EllipsisLoc);
1275
1276 return Result;
1277}
1278
1279ParsedTemplateArgument Parser::ParseTemplateArgument() {
1280 // C++ [temp.arg]p2:
1281 // In a template-argument, an ambiguity between a type-id and an
1282 // expression is resolved to a type-id, regardless of the form of
1283 // the corresponding template-parameter.
1284 //
1285 // Therefore, we initially try to parse a type-id - and isCXXTypeId might look
1286 // up and annotate an identifier as an id-expression during disambiguation,
1287 // so enter the appropriate context for a constant expression template
1288 // argument before trying to disambiguate.
1289
1290 EnterExpressionEvaluationContext EnterConstantEvaluated(
1291 Actions, Sema::ExpressionEvaluationContext::ConstantEvaluated,
1292 /*LambdaContextDecl=*/nullptr,
1293 /*ExprContext=*/Sema::ExpressionEvaluationContextRecord::EK_TemplateArgument);
1294 if (isCXXTypeId(Context: TentativeCXXTypeIdContext::AsTemplateArgument)) {
1295 TypeResult TypeArg = ParseTypeName(
1296 /*Range=*/nullptr, Context: DeclaratorContext::TemplateArg);
1297 return Actions.ActOnTemplateTypeArgument(ParsedType: TypeArg);
1298 }
1299
1300 // Try to parse a template template argument.
1301 {
1302 TentativeParsingAction TPA(*this);
1303
1304 ParsedTemplateArgument TemplateTemplateArgument
1305 = ParseTemplateTemplateArgument();
1306 if (!TemplateTemplateArgument.isInvalid()) {
1307 TPA.Commit();
1308 return TemplateTemplateArgument;
1309 }
1310
1311 // Revert this tentative parse to parse a non-type template argument.
1312 TPA.Revert();
1313 }
1314
1315 // Parse a non-type template argument.
1316 ExprResult ExprArg;
1317 SourceLocation Loc = Tok.getLocation();
1318 if (getLangOpts().CPlusPlus11 && Tok.is(K: tok::l_brace))
1319 ExprArg = ParseBraceInitializer();
1320 else
1321 ExprArg =
1322 ParseConstantExpressionInExprEvalContext(isTypeCast: TypeCastState::MaybeTypeCast);
1323 if (ExprArg.isInvalid() || !ExprArg.get()) {
1324 return ParsedTemplateArgument();
1325 }
1326
1327 return ParsedTemplateArgument(ParsedTemplateArgument::NonType,
1328 ExprArg.get(), Loc);
1329}
1330
1331bool Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs,
1332 TemplateTy Template,
1333 SourceLocation OpenLoc) {
1334
1335 ColonProtectionRAIIObject ColonProtection(*this, false);
1336
1337 auto RunSignatureHelp = [&] {
1338 if (!Template)
1339 return QualType();
1340 CalledSignatureHelp = true;
1341 return Actions.CodeCompletion().ProduceTemplateArgumentSignatureHelp(
1342 Template, TemplateArgs, LAngleLoc: OpenLoc);
1343 };
1344
1345 do {
1346 PreferredType.enterFunctionArgument(Tok: Tok.getLocation(), ComputeType: RunSignatureHelp);
1347 ParsedTemplateArgument Arg = ParseTemplateArgument();
1348 SourceLocation EllipsisLoc;
1349 if (TryConsumeToken(Expected: tok::ellipsis, Loc&: EllipsisLoc))
1350 Arg = Actions.ActOnPackExpansion(Arg, EllipsisLoc);
1351
1352 if (Arg.isInvalid()) {
1353 if (PP.isCodeCompletionReached() && !CalledSignatureHelp)
1354 RunSignatureHelp();
1355 return true;
1356 }
1357
1358 // Save this template argument.
1359 TemplateArgs.push_back(Elt: Arg);
1360
1361 // If the next token is a comma, consume it and keep reading
1362 // arguments.
1363 } while (TryConsumeToken(Expected: tok::comma));
1364
1365 return false;
1366}
1367
1368Parser::DeclGroupPtrTy Parser::ParseExplicitInstantiation(
1369 DeclaratorContext Context, SourceLocation ExternLoc,
1370 SourceLocation TemplateLoc, SourceLocation &DeclEnd,
1371 ParsedAttributes &AccessAttrs, AccessSpecifier AS) {
1372 // This isn't really required here.
1373 ParsingDeclRAIIObject
1374 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
1375 ParsedTemplateInfo TemplateInfo(ExternLoc, TemplateLoc);
1376 return ParseDeclarationAfterTemplate(
1377 Context, TemplateInfo, DiagsFromTParams&: ParsingTemplateParams, DeclEnd, AccessAttrs, AS);
1378}
1379
1380SourceRange Parser::ParsedTemplateInfo::getSourceRange() const {
1381 if (TemplateParams)
1382 return getTemplateParamsRange(Params: TemplateParams->data(),
1383 NumParams: TemplateParams->size());
1384
1385 SourceRange R(TemplateLoc);
1386 if (ExternLoc.isValid())
1387 R.setBegin(ExternLoc);
1388 return R;
1389}
1390
1391void Parser::LateTemplateParserCallback(void *P, LateParsedTemplate &LPT) {
1392 ((Parser *)P)->ParseLateTemplatedFuncDef(LPT);
1393}
1394
1395void Parser::ParseLateTemplatedFuncDef(LateParsedTemplate &LPT) {
1396 if (!LPT.D)
1397 return;
1398
1399 // Destroy TemplateIdAnnotations when we're done, if possible.
1400 DestroyTemplateIdAnnotationsRAIIObj CleanupRAII(*this);
1401
1402 // Get the FunctionDecl.
1403 FunctionDecl *FunD = LPT.D->getAsFunction();
1404 // Track template parameter depth.
1405 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
1406
1407 // To restore the context after late parsing.
1408 Sema::ContextRAII GlobalSavedContext(
1409 Actions, Actions.Context.getTranslationUnitDecl());
1410
1411 MultiParseScope Scopes(*this);
1412
1413 // Get the list of DeclContexts to reenter.
1414 SmallVector<DeclContext*, 4> DeclContextsToReenter;
1415 for (DeclContext *DC = FunD; DC && !DC->isTranslationUnit();
1416 DC = DC->getLexicalParent())
1417 DeclContextsToReenter.push_back(Elt: DC);
1418
1419 // Reenter scopes from outermost to innermost.
1420 for (DeclContext *DC : reverse(C&: DeclContextsToReenter)) {
1421 CurTemplateDepthTracker.addDepth(
1422 D: ReenterTemplateScopes(S&: Scopes, D: cast<Decl>(Val: DC)));
1423 Scopes.Enter(ScopeFlags: Scope::DeclScope);
1424 // We'll reenter the function context itself below.
1425 if (DC != FunD)
1426 Actions.PushDeclContext(S: Actions.getCurScope(), DC);
1427 }
1428
1429 // Parsing should occur with empty FP pragma stack and FP options used in the
1430 // point of the template definition.
1431 Sema::FpPragmaStackSaveRAII SavedStack(Actions);
1432 Actions.resetFPOptions(FPO: LPT.FPO);
1433
1434 assert(!LPT.Toks.empty() && "Empty body!");
1435
1436 // Append the current token at the end of the new token stream so that it
1437 // doesn't get lost.
1438 LPT.Toks.push_back(Elt: Tok);
1439 PP.EnterTokenStream(Toks: LPT.Toks, DisableMacroExpansion: true, /*IsReinject*/true);
1440
1441 // Consume the previously pushed token.
1442 ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1443 assert(Tok.isOneOf(tok::l_brace, tok::colon, tok::kw_try) &&
1444 "Inline method not starting with '{', ':' or 'try'");
1445
1446 // Parse the method body. Function body parsing code is similar enough
1447 // to be re-used for method bodies as well.
1448 ParseScope FnScope(this, Scope::FnScope | Scope::DeclScope |
1449 Scope::CompoundStmtScope);
1450
1451 // Recreate the containing function DeclContext.
1452 Sema::ContextRAII FunctionSavedContext(Actions, FunD->getLexicalParent());
1453
1454 Actions.ActOnStartOfFunctionDef(S: getCurScope(), D: FunD);
1455
1456 if (Tok.is(K: tok::kw_try)) {
1457 ParseFunctionTryBlock(Decl: LPT.D, BodyScope&: FnScope);
1458 } else {
1459 if (Tok.is(K: tok::colon))
1460 ParseConstructorInitializer(ConstructorDecl: LPT.D);
1461 else
1462 Actions.ActOnDefaultCtorInitializers(CDtorDecl: LPT.D);
1463
1464 if (Tok.is(K: tok::l_brace)) {
1465 assert((!isa<FunctionTemplateDecl>(LPT.D) ||
1466 cast<FunctionTemplateDecl>(LPT.D)
1467 ->getTemplateParameters()
1468 ->getDepth() == TemplateParameterDepth - 1) &&
1469 "TemplateParameterDepth should be greater than the depth of "
1470 "current template being instantiated!");
1471 ParseFunctionStatementBody(Decl: LPT.D, BodyScope&: FnScope);
1472 Actions.UnmarkAsLateParsedTemplate(FD: FunD);
1473 } else
1474 Actions.ActOnFinishFunctionBody(Decl: LPT.D, Body: nullptr);
1475 }
1476}
1477
1478void Parser::LexTemplateFunctionForLateParsing(CachedTokens &Toks) {
1479 tok::TokenKind kind = Tok.getKind();
1480 if (!ConsumeAndStoreFunctionPrologue(Toks)) {
1481 // Consume everything up to (and including) the matching right brace.
1482 ConsumeAndStoreUntil(T1: tok::r_brace, Toks, /*StopAtSemi=*/false);
1483 }
1484
1485 // If we're in a function-try-block, we need to store all the catch blocks.
1486 if (kind == tok::kw_try) {
1487 while (Tok.is(K: tok::kw_catch)) {
1488 ConsumeAndStoreUntil(T1: tok::l_brace, Toks, /*StopAtSemi=*/false);
1489 ConsumeAndStoreUntil(T1: tok::r_brace, Toks, /*StopAtSemi=*/false);
1490 }
1491 }
1492}
1493
1494bool Parser::diagnoseUnknownTemplateId(ExprResult LHS, SourceLocation Less) {
1495 TentativeParsingAction TPA(*this);
1496 // FIXME: We could look at the token sequence in a lot more detail here.
1497 if (SkipUntil(T1: tok::greater, T2: tok::greatergreater, T3: tok::greatergreatergreater,
1498 Flags: StopAtSemi | StopBeforeMatch)) {
1499 TPA.Commit();
1500
1501 SourceLocation Greater;
1502 ParseGreaterThanInTemplateList(LAngleLoc: Less, RAngleLoc&: Greater, ConsumeLastToken: true, ObjCGenericList: false);
1503 Actions.diagnoseExprIntendedAsTemplateName(S: getCurScope(), TemplateName: LHS,
1504 Less, Greater);
1505 return true;
1506 }
1507
1508 // There's no matching '>' token, this probably isn't supposed to be
1509 // interpreted as a template-id. Parse it as an (ill-formed) comparison.
1510 TPA.Revert();
1511 return false;
1512}
1513
1514void Parser::checkPotentialAngleBracket(ExprResult &PotentialTemplateName) {
1515 assert(Tok.is(tok::less) && "not at a potential angle bracket");
1516
1517 bool DependentTemplateName = false;
1518 if (!Actions.mightBeIntendedToBeTemplateName(E: PotentialTemplateName,
1519 Dependent&: DependentTemplateName))
1520 return;
1521
1522 // OK, this might be a name that the user intended to be parsed as a
1523 // template-name, followed by a '<' token. Check for some easy cases.
1524
1525 // If we have potential_template<>, then it's supposed to be a template-name.
1526 if (NextToken().is(K: tok::greater) ||
1527 (getLangOpts().CPlusPlus11 &&
1528 NextToken().isOneOf(Ks: tok::greatergreater, Ks: tok::greatergreatergreater))) {
1529 SourceLocation Less = ConsumeToken();
1530 SourceLocation Greater;
1531 ParseGreaterThanInTemplateList(LAngleLoc: Less, RAngleLoc&: Greater, ConsumeLastToken: true, ObjCGenericList: false);
1532 Actions.diagnoseExprIntendedAsTemplateName(
1533 S: getCurScope(), TemplateName: PotentialTemplateName, Less, Greater);
1534 // FIXME: Perform error recovery.
1535 PotentialTemplateName = ExprError();
1536 return;
1537 }
1538
1539 // If we have 'potential_template<type-id', assume it's supposed to be a
1540 // template-name if there's a matching '>' later on.
1541 {
1542 // FIXME: Avoid the tentative parse when NextToken() can't begin a type.
1543 TentativeParsingAction TPA(*this);
1544 SourceLocation Less = ConsumeToken();
1545 if (isTypeIdUnambiguously() &&
1546 diagnoseUnknownTemplateId(LHS: PotentialTemplateName, Less)) {
1547 TPA.Commit();
1548 // FIXME: Perform error recovery.
1549 PotentialTemplateName = ExprError();
1550 return;
1551 }
1552 TPA.Revert();
1553 }
1554
1555 // Otherwise, remember that we saw this in case we see a potentially-matching
1556 // '>' token later on.
1557 AngleBracketTracker::Priority Priority =
1558 (DependentTemplateName ? AngleBracketTracker::DependentName
1559 : AngleBracketTracker::PotentialTypo) |
1560 (Tok.hasLeadingSpace() ? AngleBracketTracker::SpaceBeforeLess
1561 : AngleBracketTracker::NoSpaceBeforeLess);
1562 AngleBrackets.add(P&: *this, TemplateName: PotentialTemplateName.get(), LessLoc: Tok.getLocation(),
1563 Prio: Priority);
1564}
1565
1566bool Parser::checkPotentialAngleBracketDelimiter(
1567 const AngleBracketTracker::Loc &LAngle, const Token &OpToken) {
1568 // If a comma in an expression context is followed by a type that can be a
1569 // template argument and cannot be an expression, then this is ill-formed,
1570 // but might be intended to be part of a template-id.
1571 if (OpToken.is(K: tok::comma) && isTypeIdUnambiguously() &&
1572 diagnoseUnknownTemplateId(LHS: LAngle.TemplateName, Less: LAngle.LessLoc)) {
1573 AngleBrackets.clear(P&: *this);
1574 return true;
1575 }
1576
1577 // If a context that looks like a template-id is followed by '()', then
1578 // this is ill-formed, but might be intended to be a template-id
1579 // followed by '()'.
1580 if (OpToken.is(K: tok::greater) && Tok.is(K: tok::l_paren) &&
1581 NextToken().is(K: tok::r_paren)) {
1582 Actions.diagnoseExprIntendedAsTemplateName(
1583 S: getCurScope(), TemplateName: LAngle.TemplateName, Less: LAngle.LessLoc,
1584 Greater: OpToken.getLocation());
1585 AngleBrackets.clear(P&: *this);
1586 return true;
1587 }
1588
1589 // After a '>' (etc), we're no longer potentially in a construct that's
1590 // intended to be treated as a template-id.
1591 if (OpToken.is(K: tok::greater) ||
1592 (getLangOpts().CPlusPlus11 &&
1593 OpToken.isOneOf(Ks: tok::greatergreater, Ks: tok::greatergreatergreater)))
1594 AngleBrackets.clear(P&: *this);
1595 return false;
1596}
1597