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comparison tools/clang/lib/Parse/ParseTemplate.cpp @ 0:95c75e76d11b LLVM3.4

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LLVM 3.4
author Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
date Thu, 12 Dec 2013 13:56:28 +0900
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children e4204d083e25
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-1:000000000000 0:95c75e76d11b
1 //===--- ParseTemplate.cpp - Template Parsing -----------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements parsing of C++ templates.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/Parse/Parser.h"
15 #include "RAIIObjectsForParser.h"
16 #include "clang/AST/ASTConsumer.h"
17 #include "clang/AST/DeclTemplate.h"
18 #include "clang/Parse/ParseDiagnostic.h"
19 #include "clang/Sema/DeclSpec.h"
20 #include "clang/Sema/ParsedTemplate.h"
21 #include "clang/Sema/Scope.h"
22 using namespace clang;
23
24 /// \brief Parse a template declaration, explicit instantiation, or
25 /// explicit specialization.
26 Decl *
27 Parser::ParseDeclarationStartingWithTemplate(unsigned Context,
28 SourceLocation &DeclEnd,
29 AccessSpecifier AS,
30 AttributeList *AccessAttrs) {
31 ObjCDeclContextSwitch ObjCDC(*this);
32
33 if (Tok.is(tok::kw_template) && NextToken().isNot(tok::less)) {
34 return ParseExplicitInstantiation(Context,
35 SourceLocation(), ConsumeToken(),
36 DeclEnd, AS);
37 }
38 return ParseTemplateDeclarationOrSpecialization(Context, DeclEnd, AS,
39 AccessAttrs);
40 }
41
42
43
44 /// \brief Parse a template declaration or an explicit specialization.
45 ///
46 /// Template declarations include one or more template parameter lists
47 /// and either the function or class template declaration. Explicit
48 /// specializations contain one or more 'template < >' prefixes
49 /// followed by a (possibly templated) declaration. Since the
50 /// syntactic form of both features is nearly identical, we parse all
51 /// of the template headers together and let semantic analysis sort
52 /// the declarations from the explicit specializations.
53 ///
54 /// template-declaration: [C++ temp]
55 /// 'export'[opt] 'template' '<' template-parameter-list '>' declaration
56 ///
57 /// explicit-specialization: [ C++ temp.expl.spec]
58 /// 'template' '<' '>' declaration
59 Decl *
60 Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context,
61 SourceLocation &DeclEnd,
62 AccessSpecifier AS,
63 AttributeList *AccessAttrs) {
64 assert((Tok.is(tok::kw_export) || Tok.is(tok::kw_template)) &&
65 "Token does not start a template declaration.");
66
67 // Enter template-parameter scope.
68 ParseScope TemplateParmScope(this, Scope::TemplateParamScope);
69
70 // Tell the action that names should be checked in the context of
71 // the declaration to come.
72 ParsingDeclRAIIObject
73 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
74
75 // Parse multiple levels of template headers within this template
76 // parameter scope, e.g.,
77 //
78 // template<typename T>
79 // template<typename U>
80 // class A<T>::B { ... };
81 //
82 // We parse multiple levels non-recursively so that we can build a
83 // single data structure containing all of the template parameter
84 // lists to easily differentiate between the case above and:
85 //
86 // template<typename T>
87 // class A {
88 // template<typename U> class B;
89 // };
90 //
91 // In the first case, the action for declaring A<T>::B receives
92 // both template parameter lists. In the second case, the action for
93 // defining A<T>::B receives just the inner template parameter list
94 // (and retrieves the outer template parameter list from its
95 // context).
96 bool isSpecialization = true;
97 bool LastParamListWasEmpty = false;
98 TemplateParameterLists ParamLists;
99 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
100
101 do {
102 // Consume the 'export', if any.
103 SourceLocation ExportLoc;
104 if (Tok.is(tok::kw_export)) {
105 ExportLoc = ConsumeToken();
106 }
107
108 // Consume the 'template', which should be here.
109 SourceLocation TemplateLoc;
110 if (Tok.is(tok::kw_template)) {
111 TemplateLoc = ConsumeToken();
112 } else {
113 Diag(Tok.getLocation(), diag::err_expected_template);
114 return 0;
115 }
116
117 // Parse the '<' template-parameter-list '>'
118 SourceLocation LAngleLoc, RAngleLoc;
119 SmallVector<Decl*, 4> TemplateParams;
120 if (ParseTemplateParameters(CurTemplateDepthTracker.getDepth(),
121 TemplateParams, LAngleLoc, RAngleLoc)) {
122 // Skip until the semi-colon or a }.
123 SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
124 if (Tok.is(tok::semi))
125 ConsumeToken();
126 return 0;
127 }
128
129 ParamLists.push_back(
130 Actions.ActOnTemplateParameterList(CurTemplateDepthTracker.getDepth(),
131 ExportLoc,
132 TemplateLoc, LAngleLoc,
133 TemplateParams.data(),
134 TemplateParams.size(), RAngleLoc));
135
136 if (!TemplateParams.empty()) {
137 isSpecialization = false;
138 ++CurTemplateDepthTracker;
139 } else {
140 LastParamListWasEmpty = true;
141 }
142 } while (Tok.is(tok::kw_export) || Tok.is(tok::kw_template));
143
144 // Parse the actual template declaration.
145 return ParseSingleDeclarationAfterTemplate(Context,
146 ParsedTemplateInfo(&ParamLists,
147 isSpecialization,
148 LastParamListWasEmpty),
149 ParsingTemplateParams,
150 DeclEnd, AS, AccessAttrs);
151 }
152
153 /// \brief Parse a single declaration that declares a template,
154 /// template specialization, or explicit instantiation of a template.
155 ///
156 /// \param DeclEnd will receive the source location of the last token
157 /// within this declaration.
158 ///
159 /// \param AS the access specifier associated with this
160 /// declaration. Will be AS_none for namespace-scope declarations.
161 ///
162 /// \returns the new declaration.
163 Decl *
164 Parser::ParseSingleDeclarationAfterTemplate(
165 unsigned Context,
166 const ParsedTemplateInfo &TemplateInfo,
167 ParsingDeclRAIIObject &DiagsFromTParams,
168 SourceLocation &DeclEnd,
169 AccessSpecifier AS,
170 AttributeList *AccessAttrs) {
171 assert(TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
172 "Template information required");
173
174 if (Context == Declarator::MemberContext) {
175 // We are parsing a member template.
176 ParseCXXClassMemberDeclaration(AS, AccessAttrs, TemplateInfo,
177 &DiagsFromTParams);
178 return 0;
179 }
180
181 ParsedAttributesWithRange prefixAttrs(AttrFactory);
182 MaybeParseCXX11Attributes(prefixAttrs);
183
184 if (Tok.is(tok::kw_using))
185 return ParseUsingDirectiveOrDeclaration(Context, TemplateInfo, DeclEnd,
186 prefixAttrs);
187
188 // Parse the declaration specifiers, stealing any diagnostics from
189 // the template parameters.
190 ParsingDeclSpec DS(*this, &DiagsFromTParams);
191
192 ParseDeclarationSpecifiers(DS, TemplateInfo, AS,
193 getDeclSpecContextFromDeclaratorContext(Context));
194
195 if (Tok.is(tok::semi)) {
196 ProhibitAttributes(prefixAttrs);
197 DeclEnd = ConsumeToken();
198 Decl *Decl = Actions.ParsedFreeStandingDeclSpec(
199 getCurScope(), AS, DS,
200 TemplateInfo.TemplateParams ? *TemplateInfo.TemplateParams
201 : MultiTemplateParamsArg(),
202 TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation);
203 DS.complete(Decl);
204 return Decl;
205 }
206
207 // Move the attributes from the prefix into the DS.
208 if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation)
209 ProhibitAttributes(prefixAttrs);
210 else
211 DS.takeAttributesFrom(prefixAttrs);
212
213 // Parse the declarator.
214 ParsingDeclarator DeclaratorInfo(*this, DS, (Declarator::TheContext)Context);
215 ParseDeclarator(DeclaratorInfo);
216 // Error parsing the declarator?
217 if (!DeclaratorInfo.hasName()) {
218 // If so, skip until the semi-colon or a }.
219 SkipUntil(tok::r_brace, StopAtSemi | StopBeforeMatch);
220 if (Tok.is(tok::semi))
221 ConsumeToken();
222 return 0;
223 }
224
225 LateParsedAttrList LateParsedAttrs(true);
226 if (DeclaratorInfo.isFunctionDeclarator())
227 MaybeParseGNUAttributes(DeclaratorInfo, &LateParsedAttrs);
228
229 if (DeclaratorInfo.isFunctionDeclarator() &&
230 isStartOfFunctionDefinition(DeclaratorInfo)) {
231 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) {
232 // Recover by ignoring the 'typedef'. This was probably supposed to be
233 // the 'typename' keyword, which we should have already suggested adding
234 // if it's appropriate.
235 Diag(DS.getStorageClassSpecLoc(), diag::err_function_declared_typedef)
236 << FixItHint::CreateRemoval(DS.getStorageClassSpecLoc());
237 DS.ClearStorageClassSpecs();
238 }
239
240 if (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation) {
241 if (DeclaratorInfo.getName().getKind() != UnqualifiedId::IK_TemplateId) {
242 // If the declarator-id is not a template-id, issue a diagnostic and
243 // recover by ignoring the 'template' keyword.
244 Diag(Tok, diag::err_template_defn_explicit_instantiation) << 0;
245 return ParseFunctionDefinition(DeclaratorInfo, ParsedTemplateInfo(),
246 &LateParsedAttrs);
247 } else {
248 SourceLocation LAngleLoc
249 = PP.getLocForEndOfToken(TemplateInfo.TemplateLoc);
250 Diag(DeclaratorInfo.getIdentifierLoc(),
251 diag::err_explicit_instantiation_with_definition)
252 << SourceRange(TemplateInfo.TemplateLoc)
253 << FixItHint::CreateInsertion(LAngleLoc, "<>");
254
255 // Recover as if it were an explicit specialization.
256 TemplateParameterLists FakedParamLists;
257 FakedParamLists.push_back(Actions.ActOnTemplateParameterList(
258 0, SourceLocation(), TemplateInfo.TemplateLoc, LAngleLoc, 0, 0,
259 LAngleLoc));
260
261 return ParseFunctionDefinition(
262 DeclaratorInfo, ParsedTemplateInfo(&FakedParamLists,
263 /*isSpecialization=*/true,
264 /*LastParamListWasEmpty=*/true),
265 &LateParsedAttrs);
266 }
267 }
268 return ParseFunctionDefinition(DeclaratorInfo, TemplateInfo,
269 &LateParsedAttrs);
270 }
271
272 // Parse this declaration.
273 Decl *ThisDecl = ParseDeclarationAfterDeclarator(DeclaratorInfo,
274 TemplateInfo);
275
276 if (Tok.is(tok::comma)) {
277 Diag(Tok, diag::err_multiple_template_declarators)
278 << (int)TemplateInfo.Kind;
279 SkipUntil(tok::semi);
280 return ThisDecl;
281 }
282
283 // Eat the semi colon after the declaration.
284 ExpectAndConsumeSemi(diag::err_expected_semi_declaration);
285 if (LateParsedAttrs.size() > 0)
286 ParseLexedAttributeList(LateParsedAttrs, ThisDecl, true, false);
287 DeclaratorInfo.complete(ThisDecl);
288 return ThisDecl;
289 }
290
291 /// ParseTemplateParameters - Parses a template-parameter-list enclosed in
292 /// angle brackets. Depth is the depth of this template-parameter-list, which
293 /// is the number of template headers directly enclosing this template header.
294 /// TemplateParams is the current list of template parameters we're building.
295 /// The template parameter we parse will be added to this list. LAngleLoc and
296 /// RAngleLoc will receive the positions of the '<' and '>', respectively,
297 /// that enclose this template parameter list.
298 ///
299 /// \returns true if an error occurred, false otherwise.
300 bool Parser::ParseTemplateParameters(unsigned Depth,
301 SmallVectorImpl<Decl*> &TemplateParams,
302 SourceLocation &LAngleLoc,
303 SourceLocation &RAngleLoc) {
304 // Get the template parameter list.
305 if (!Tok.is(tok::less)) {
306 Diag(Tok.getLocation(), diag::err_expected_less_after) << "template";
307 return true;
308 }
309 LAngleLoc = ConsumeToken();
310
311 // Try to parse the template parameter list.
312 bool Failed = false;
313 if (!Tok.is(tok::greater) && !Tok.is(tok::greatergreater))
314 Failed = ParseTemplateParameterList(Depth, TemplateParams);
315
316 if (Tok.is(tok::greatergreater)) {
317 // No diagnostic required here: a template-parameter-list can only be
318 // followed by a declaration or, for a template template parameter, the
319 // 'class' keyword. Therefore, the second '>' will be diagnosed later.
320 // This matters for elegant diagnosis of:
321 // template<template<typename>> struct S;
322 Tok.setKind(tok::greater);
323 RAngleLoc = Tok.getLocation();
324 Tok.setLocation(Tok.getLocation().getLocWithOffset(1));
325 } else if (Tok.is(tok::greater))
326 RAngleLoc = ConsumeToken();
327 else if (Failed) {
328 Diag(Tok.getLocation(), diag::err_expected_greater);
329 return true;
330 }
331 return false;
332 }
333
334 /// ParseTemplateParameterList - Parse a template parameter list. If
335 /// the parsing fails badly (i.e., closing bracket was left out), this
336 /// will try to put the token stream in a reasonable position (closing
337 /// a statement, etc.) and return false.
338 ///
339 /// template-parameter-list: [C++ temp]
340 /// template-parameter
341 /// template-parameter-list ',' template-parameter
342 bool
343 Parser::ParseTemplateParameterList(unsigned Depth,
344 SmallVectorImpl<Decl*> &TemplateParams) {
345 while (1) {
346 if (Decl *TmpParam
347 = ParseTemplateParameter(Depth, TemplateParams.size())) {
348 TemplateParams.push_back(TmpParam);
349 } else {
350 // If we failed to parse a template parameter, skip until we find
351 // a comma or closing brace.
352 SkipUntil(tok::comma, tok::greater, tok::greatergreater,
353 StopAtSemi | StopBeforeMatch);
354 }
355
356 // Did we find a comma or the end of the template parameter list?
357 if (Tok.is(tok::comma)) {
358 ConsumeToken();
359 } else if (Tok.is(tok::greater) || Tok.is(tok::greatergreater)) {
360 // Don't consume this... that's done by template parser.
361 break;
362 } else {
363 // Somebody probably forgot to close the template. Skip ahead and
364 // try to get out of the expression. This error is currently
365 // subsumed by whatever goes on in ParseTemplateParameter.
366 Diag(Tok.getLocation(), diag::err_expected_comma_greater);
367 SkipUntil(tok::comma, tok::greater, tok::greatergreater,
368 StopAtSemi | StopBeforeMatch);
369 return false;
370 }
371 }
372 return true;
373 }
374
375 /// \brief Determine whether the parser is at the start of a template
376 /// type parameter.
377 bool Parser::isStartOfTemplateTypeParameter() {
378 if (Tok.is(tok::kw_class)) {
379 // "class" may be the start of an elaborated-type-specifier or a
380 // type-parameter. Per C++ [temp.param]p3, we prefer the type-parameter.
381 switch (NextToken().getKind()) {
382 case tok::equal:
383 case tok::comma:
384 case tok::greater:
385 case tok::greatergreater:
386 case tok::ellipsis:
387 return true;
388
389 case tok::identifier:
390 // This may be either a type-parameter or an elaborated-type-specifier.
391 // We have to look further.
392 break;
393
394 default:
395 return false;
396 }
397
398 switch (GetLookAheadToken(2).getKind()) {
399 case tok::equal:
400 case tok::comma:
401 case tok::greater:
402 case tok::greatergreater:
403 return true;
404
405 default:
406 return false;
407 }
408 }
409
410 if (Tok.isNot(tok::kw_typename))
411 return false;
412
413 // C++ [temp.param]p2:
414 // There is no semantic difference between class and typename in a
415 // template-parameter. typename followed by an unqualified-id
416 // names a template type parameter. typename followed by a
417 // qualified-id denotes the type in a non-type
418 // parameter-declaration.
419 Token Next = NextToken();
420
421 // If we have an identifier, skip over it.
422 if (Next.getKind() == tok::identifier)
423 Next = GetLookAheadToken(2);
424
425 switch (Next.getKind()) {
426 case tok::equal:
427 case tok::comma:
428 case tok::greater:
429 case tok::greatergreater:
430 case tok::ellipsis:
431 return true;
432
433 default:
434 return false;
435 }
436 }
437
438 /// ParseTemplateParameter - Parse a template-parameter (C++ [temp.param]).
439 ///
440 /// template-parameter: [C++ temp.param]
441 /// type-parameter
442 /// parameter-declaration
443 ///
444 /// type-parameter: (see below)
445 /// 'class' ...[opt] identifier[opt]
446 /// 'class' identifier[opt] '=' type-id
447 /// 'typename' ...[opt] identifier[opt]
448 /// 'typename' identifier[opt] '=' type-id
449 /// 'template' '<' template-parameter-list '>'
450 /// 'class' ...[opt] identifier[opt]
451 /// 'template' '<' template-parameter-list '>' 'class' identifier[opt]
452 /// = id-expression
453 Decl *Parser::ParseTemplateParameter(unsigned Depth, unsigned Position) {
454 if (isStartOfTemplateTypeParameter())
455 return ParseTypeParameter(Depth, Position);
456
457 if (Tok.is(tok::kw_template))
458 return ParseTemplateTemplateParameter(Depth, Position);
459
460 // If it's none of the above, then it must be a parameter declaration.
461 // NOTE: This will pick up errors in the closure of the template parameter
462 // list (e.g., template < ; Check here to implement >> style closures.
463 return ParseNonTypeTemplateParameter(Depth, Position);
464 }
465
466 /// ParseTypeParameter - Parse a template type parameter (C++ [temp.param]).
467 /// Other kinds of template parameters are parsed in
468 /// ParseTemplateTemplateParameter and ParseNonTypeTemplateParameter.
469 ///
470 /// type-parameter: [C++ temp.param]
471 /// 'class' ...[opt][C++0x] identifier[opt]
472 /// 'class' identifier[opt] '=' type-id
473 /// 'typename' ...[opt][C++0x] identifier[opt]
474 /// 'typename' identifier[opt] '=' type-id
475 Decl *Parser::ParseTypeParameter(unsigned Depth, unsigned Position) {
476 assert((Tok.is(tok::kw_class) || Tok.is(tok::kw_typename)) &&
477 "A type-parameter starts with 'class' or 'typename'");
478
479 // Consume the 'class' or 'typename' keyword.
480 bool TypenameKeyword = Tok.is(tok::kw_typename);
481 SourceLocation KeyLoc = ConsumeToken();
482
483 // Grab the ellipsis (if given).
484 bool Ellipsis = false;
485 SourceLocation EllipsisLoc;
486 if (Tok.is(tok::ellipsis)) {
487 Ellipsis = true;
488 EllipsisLoc = ConsumeToken();
489
490 Diag(EllipsisLoc,
491 getLangOpts().CPlusPlus11
492 ? diag::warn_cxx98_compat_variadic_templates
493 : diag::ext_variadic_templates);
494 }
495
496 // Grab the template parameter name (if given)
497 SourceLocation NameLoc;
498 IdentifierInfo* ParamName = 0;
499 if (Tok.is(tok::identifier)) {
500 ParamName = Tok.getIdentifierInfo();
501 NameLoc = ConsumeToken();
502 } else if (Tok.is(tok::equal) || Tok.is(tok::comma) ||
503 Tok.is(tok::greater) || Tok.is(tok::greatergreater)) {
504 // Unnamed template parameter. Don't have to do anything here, just
505 // don't consume this token.
506 } else {
507 Diag(Tok.getLocation(), diag::err_expected_ident);
508 return 0;
509 }
510
511 // Grab a default argument (if available).
512 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
513 // we introduce the type parameter into the local scope.
514 SourceLocation EqualLoc;
515 ParsedType DefaultArg;
516 if (Tok.is(tok::equal)) {
517 EqualLoc = ConsumeToken();
518 DefaultArg = ParseTypeName(/*Range=*/0,
519 Declarator::TemplateTypeArgContext).get();
520 }
521
522 return Actions.ActOnTypeParameter(getCurScope(), TypenameKeyword, Ellipsis,
523 EllipsisLoc, KeyLoc, ParamName, NameLoc,
524 Depth, Position, EqualLoc, DefaultArg);
525 }
526
527 /// ParseTemplateTemplateParameter - Handle the parsing of template
528 /// template parameters.
529 ///
530 /// type-parameter: [C++ temp.param]
531 /// 'template' '<' template-parameter-list '>' 'class'
532 /// ...[opt] identifier[opt]
533 /// 'template' '<' template-parameter-list '>' 'class' identifier[opt]
534 /// = id-expression
535 Decl *
536 Parser::ParseTemplateTemplateParameter(unsigned Depth, unsigned Position) {
537 assert(Tok.is(tok::kw_template) && "Expected 'template' keyword");
538
539 // Handle the template <...> part.
540 SourceLocation TemplateLoc = ConsumeToken();
541 SmallVector<Decl*,8> TemplateParams;
542 SourceLocation LAngleLoc, RAngleLoc;
543 {
544 ParseScope TemplateParmScope(this, Scope::TemplateParamScope);
545 if (ParseTemplateParameters(Depth + 1, TemplateParams, LAngleLoc,
546 RAngleLoc)) {
547 return 0;
548 }
549 }
550
551 // Generate a meaningful error if the user forgot to put class before the
552 // identifier, comma, or greater. Provide a fixit if the identifier, comma,
553 // or greater appear immediately or after 'typename' or 'struct'. In the
554 // latter case, replace the keyword with 'class'.
555 if (!Tok.is(tok::kw_class)) {
556 bool Replace = Tok.is(tok::kw_typename) || Tok.is(tok::kw_struct);
557 const Token& Next = Replace ? NextToken() : Tok;
558 if (Next.is(tok::identifier) || Next.is(tok::comma) ||
559 Next.is(tok::greater) || Next.is(tok::greatergreater) ||
560 Next.is(tok::ellipsis))
561 Diag(Tok.getLocation(), diag::err_class_on_template_template_param)
562 << (Replace ? FixItHint::CreateReplacement(Tok.getLocation(), "class")
563 : FixItHint::CreateInsertion(Tok.getLocation(), "class "));
564 else
565 Diag(Tok.getLocation(), diag::err_class_on_template_template_param);
566
567 if (Replace)
568 ConsumeToken();
569 } else
570 ConsumeToken();
571
572 // Parse the ellipsis, if given.
573 SourceLocation EllipsisLoc;
574 if (Tok.is(tok::ellipsis)) {
575 EllipsisLoc = ConsumeToken();
576
577 Diag(EllipsisLoc,
578 getLangOpts().CPlusPlus11
579 ? diag::warn_cxx98_compat_variadic_templates
580 : diag::ext_variadic_templates);
581 }
582
583 // Get the identifier, if given.
584 SourceLocation NameLoc;
585 IdentifierInfo* ParamName = 0;
586 if (Tok.is(tok::identifier)) {
587 ParamName = Tok.getIdentifierInfo();
588 NameLoc = ConsumeToken();
589 } else if (Tok.is(tok::equal) || Tok.is(tok::comma) ||
590 Tok.is(tok::greater) || Tok.is(tok::greatergreater)) {
591 // Unnamed template parameter. Don't have to do anything here, just
592 // don't consume this token.
593 } else {
594 Diag(Tok.getLocation(), diag::err_expected_ident);
595 return 0;
596 }
597
598 TemplateParameterList *ParamList =
599 Actions.ActOnTemplateParameterList(Depth, SourceLocation(),
600 TemplateLoc, LAngleLoc,
601 TemplateParams.data(),
602 TemplateParams.size(),
603 RAngleLoc);
604
605 // Grab a default argument (if available).
606 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
607 // we introduce the template parameter into the local scope.
608 SourceLocation EqualLoc;
609 ParsedTemplateArgument DefaultArg;
610 if (Tok.is(tok::equal)) {
611 EqualLoc = ConsumeToken();
612 DefaultArg = ParseTemplateTemplateArgument();
613 if (DefaultArg.isInvalid()) {
614 Diag(Tok.getLocation(),
615 diag::err_default_template_template_parameter_not_template);
616 SkipUntil(tok::comma, tok::greater, tok::greatergreater,
617 StopAtSemi | StopBeforeMatch);
618 }
619 }
620
621 return Actions.ActOnTemplateTemplateParameter(getCurScope(), TemplateLoc,
622 ParamList, EllipsisLoc,
623 ParamName, NameLoc, Depth,
624 Position, EqualLoc, DefaultArg);
625 }
626
627 /// ParseNonTypeTemplateParameter - Handle the parsing of non-type
628 /// template parameters (e.g., in "template<int Size> class array;").
629 ///
630 /// template-parameter:
631 /// ...
632 /// parameter-declaration
633 Decl *
634 Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) {
635 // Parse the declaration-specifiers (i.e., the type).
636 // FIXME: The type should probably be restricted in some way... Not all
637 // declarators (parts of declarators?) are accepted for parameters.
638 DeclSpec DS(AttrFactory);
639 ParseDeclarationSpecifiers(DS);
640
641 // Parse this as a typename.
642 Declarator ParamDecl(DS, Declarator::TemplateParamContext);
643 ParseDeclarator(ParamDecl);
644 if (DS.getTypeSpecType() == DeclSpec::TST_unspecified) {
645 Diag(Tok.getLocation(), diag::err_expected_template_parameter);
646 return 0;
647 }
648
649 // If there is a default value, parse it.
650 // Per C++0x [basic.scope.pdecl]p9, we parse the default argument before
651 // we introduce the template parameter into the local scope.
652 SourceLocation EqualLoc;
653 ExprResult DefaultArg;
654 if (Tok.is(tok::equal)) {
655 EqualLoc = ConsumeToken();
656
657 // C++ [temp.param]p15:
658 // When parsing a default template-argument for a non-type
659 // template-parameter, the first non-nested > is taken as the
660 // end of the template-parameter-list rather than a greater-than
661 // operator.
662 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false);
663 EnterExpressionEvaluationContext Unevaluated(Actions, Sema::Unevaluated);
664
665 DefaultArg = ParseAssignmentExpression();
666 if (DefaultArg.isInvalid())
667 SkipUntil(tok::comma, tok::greater, StopAtSemi | StopBeforeMatch);
668 }
669
670 // Create the parameter.
671 return Actions.ActOnNonTypeTemplateParameter(getCurScope(), ParamDecl,
672 Depth, Position, EqualLoc,
673 DefaultArg.take());
674 }
675
676 /// \brief Parses a '>' at the end of a template list.
677 ///
678 /// If this function encounters '>>', '>>>', '>=', or '>>=', it tries
679 /// to determine if these tokens were supposed to be a '>' followed by
680 /// '>', '>>', '>=', or '>='. It emits an appropriate diagnostic if necessary.
681 ///
682 /// \param RAngleLoc the location of the consumed '>'.
683 ///
684 /// \param ConsumeLastToken if true, the '>' is not consumed.
685 ///
686 /// \returns true, if current token does not start with '>', false otherwise.
687 bool Parser::ParseGreaterThanInTemplateList(SourceLocation &RAngleLoc,
688 bool ConsumeLastToken) {
689 // What will be left once we've consumed the '>'.
690 tok::TokenKind RemainingToken;
691 const char *ReplacementStr = "> >";
692
693 switch (Tok.getKind()) {
694 default:
695 Diag(Tok.getLocation(), diag::err_expected_greater);
696 return true;
697
698 case tok::greater:
699 // Determine the location of the '>' token. Only consume this token
700 // if the caller asked us to.
701 RAngleLoc = Tok.getLocation();
702 if (ConsumeLastToken)
703 ConsumeToken();
704 return false;
705
706 case tok::greatergreater:
707 RemainingToken = tok::greater;
708 break;
709
710 case tok::greatergreatergreater:
711 RemainingToken = tok::greatergreater;
712 break;
713
714 case tok::greaterequal:
715 RemainingToken = tok::equal;
716 ReplacementStr = "> =";
717 break;
718
719 case tok::greatergreaterequal:
720 RemainingToken = tok::greaterequal;
721 break;
722 }
723
724 // This template-id is terminated by a token which starts with a '>'. Outside
725 // C++11, this is now error recovery, and in C++11, this is error recovery if
726 // the token isn't '>>'.
727
728 RAngleLoc = Tok.getLocation();
729
730 // The source range of the '>>' or '>=' at the start of the token.
731 CharSourceRange ReplacementRange =
732 CharSourceRange::getCharRange(RAngleLoc,
733 Lexer::AdvanceToTokenCharacter(RAngleLoc, 2, PP.getSourceManager(),
734 getLangOpts()));
735
736 // A hint to put a space between the '>>'s. In order to make the hint as
737 // clear as possible, we include the characters either side of the space in
738 // the replacement, rather than just inserting a space at SecondCharLoc.
739 FixItHint Hint1 = FixItHint::CreateReplacement(ReplacementRange,
740 ReplacementStr);
741
742 // A hint to put another space after the token, if it would otherwise be
743 // lexed differently.
744 FixItHint Hint2;
745 Token Next = NextToken();
746 if ((RemainingToken == tok::greater ||
747 RemainingToken == tok::greatergreater) &&
748 (Next.is(tok::greater) || Next.is(tok::greatergreater) ||
749 Next.is(tok::greatergreatergreater) || Next.is(tok::equal) ||
750 Next.is(tok::greaterequal) || Next.is(tok::greatergreaterequal) ||
751 Next.is(tok::equalequal)) &&
752 areTokensAdjacent(Tok, Next))
753 Hint2 = FixItHint::CreateInsertion(Next.getLocation(), " ");
754
755 unsigned DiagId = diag::err_two_right_angle_brackets_need_space;
756 if (getLangOpts().CPlusPlus11 && Tok.is(tok::greatergreater))
757 DiagId = diag::warn_cxx98_compat_two_right_angle_brackets;
758 else if (Tok.is(tok::greaterequal))
759 DiagId = diag::err_right_angle_bracket_equal_needs_space;
760 Diag(Tok.getLocation(), DiagId) << Hint1 << Hint2;
761
762 // Strip the initial '>' from the token.
763 if (RemainingToken == tok::equal && Next.is(tok::equal) &&
764 areTokensAdjacent(Tok, Next)) {
765 // Join two adjacent '=' tokens into one, for cases like:
766 // void (*p)() = f<int>;
767 // return f<int>==p;
768 ConsumeToken();
769 Tok.setKind(tok::equalequal);
770 Tok.setLength(Tok.getLength() + 1);
771 } else {
772 Tok.setKind(RemainingToken);
773 Tok.setLength(Tok.getLength() - 1);
774 }
775 Tok.setLocation(Lexer::AdvanceToTokenCharacter(RAngleLoc, 1,
776 PP.getSourceManager(),
777 getLangOpts()));
778
779 if (!ConsumeLastToken) {
780 // Since we're not supposed to consume the '>' token, we need to push
781 // this token and revert the current token back to the '>'.
782 PP.EnterToken(Tok);
783 Tok.setKind(tok::greater);
784 Tok.setLength(1);
785 Tok.setLocation(RAngleLoc);
786 }
787 return false;
788 }
789
790
791 /// \brief Parses a template-id that after the template name has
792 /// already been parsed.
793 ///
794 /// This routine takes care of parsing the enclosed template argument
795 /// list ('<' template-parameter-list [opt] '>') and placing the
796 /// results into a form that can be transferred to semantic analysis.
797 ///
798 /// \param Template the template declaration produced by isTemplateName
799 ///
800 /// \param TemplateNameLoc the source location of the template name
801 ///
802 /// \param SS if non-NULL, the nested-name-specifier preceding the
803 /// template name.
804 ///
805 /// \param ConsumeLastToken if true, then we will consume the last
806 /// token that forms the template-id. Otherwise, we will leave the
807 /// last token in the stream (e.g., so that it can be replaced with an
808 /// annotation token).
809 bool
810 Parser::ParseTemplateIdAfterTemplateName(TemplateTy Template,
811 SourceLocation TemplateNameLoc,
812 const CXXScopeSpec &SS,
813 bool ConsumeLastToken,
814 SourceLocation &LAngleLoc,
815 TemplateArgList &TemplateArgs,
816 SourceLocation &RAngleLoc) {
817 assert(Tok.is(tok::less) && "Must have already parsed the template-name");
818
819 // Consume the '<'.
820 LAngleLoc = ConsumeToken();
821
822 // Parse the optional template-argument-list.
823 bool Invalid = false;
824 {
825 GreaterThanIsOperatorScope G(GreaterThanIsOperator, false);
826 if (Tok.isNot(tok::greater) && Tok.isNot(tok::greatergreater))
827 Invalid = ParseTemplateArgumentList(TemplateArgs);
828
829 if (Invalid) {
830 // Try to find the closing '>'.
831 if (ConsumeLastToken)
832 SkipUntil(tok::greater, StopAtSemi);
833 else
834 SkipUntil(tok::greater, StopAtSemi | StopBeforeMatch);
835 return true;
836 }
837 }
838
839 return ParseGreaterThanInTemplateList(RAngleLoc, ConsumeLastToken);
840 }
841
842 /// \brief Replace the tokens that form a simple-template-id with an
843 /// annotation token containing the complete template-id.
844 ///
845 /// The first token in the stream must be the name of a template that
846 /// is followed by a '<'. This routine will parse the complete
847 /// simple-template-id and replace the tokens with a single annotation
848 /// token with one of two different kinds: if the template-id names a
849 /// type (and \p AllowTypeAnnotation is true), the annotation token is
850 /// a type annotation that includes the optional nested-name-specifier
851 /// (\p SS). Otherwise, the annotation token is a template-id
852 /// annotation that does not include the optional
853 /// nested-name-specifier.
854 ///
855 /// \param Template the declaration of the template named by the first
856 /// token (an identifier), as returned from \c Action::isTemplateName().
857 ///
858 /// \param TNK the kind of template that \p Template
859 /// refers to, as returned from \c Action::isTemplateName().
860 ///
861 /// \param SS if non-NULL, the nested-name-specifier that precedes
862 /// this template name.
863 ///
864 /// \param TemplateKWLoc if valid, specifies that this template-id
865 /// annotation was preceded by the 'template' keyword and gives the
866 /// location of that keyword. If invalid (the default), then this
867 /// template-id was not preceded by a 'template' keyword.
868 ///
869 /// \param AllowTypeAnnotation if true (the default), then a
870 /// simple-template-id that refers to a class template, template
871 /// template parameter, or other template that produces a type will be
872 /// replaced with a type annotation token. Otherwise, the
873 /// simple-template-id is always replaced with a template-id
874 /// annotation token.
875 ///
876 /// If an unrecoverable parse error occurs and no annotation token can be
877 /// formed, this function returns true.
878 ///
879 bool Parser::AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK,
880 CXXScopeSpec &SS,
881 SourceLocation TemplateKWLoc,
882 UnqualifiedId &TemplateName,
883 bool AllowTypeAnnotation) {
884 assert(getLangOpts().CPlusPlus && "Can only annotate template-ids in C++");
885 assert(Template && Tok.is(tok::less) &&
886 "Parser isn't at the beginning of a template-id");
887
888 // Consume the template-name.
889 SourceLocation TemplateNameLoc = TemplateName.getSourceRange().getBegin();
890
891 // Parse the enclosed template argument list.
892 SourceLocation LAngleLoc, RAngleLoc;
893 TemplateArgList TemplateArgs;
894 bool Invalid = ParseTemplateIdAfterTemplateName(Template,
895 TemplateNameLoc,
896 SS, false, LAngleLoc,
897 TemplateArgs,
898 RAngleLoc);
899
900 if (Invalid) {
901 // If we failed to parse the template ID but skipped ahead to a >, we're not
902 // going to be able to form a token annotation. Eat the '>' if present.
903 if (Tok.is(tok::greater))
904 ConsumeToken();
905 return true;
906 }
907
908 ASTTemplateArgsPtr TemplateArgsPtr(TemplateArgs);
909
910 // Build the annotation token.
911 if (TNK == TNK_Type_template && AllowTypeAnnotation) {
912 TypeResult Type
913 = Actions.ActOnTemplateIdType(SS, TemplateKWLoc,
914 Template, TemplateNameLoc,
915 LAngleLoc, TemplateArgsPtr, RAngleLoc);
916 if (Type.isInvalid()) {
917 // If we failed to parse the template ID but skipped ahead to a >, we're not
918 // going to be able to form a token annotation. Eat the '>' if present.
919 if (Tok.is(tok::greater))
920 ConsumeToken();
921 return true;
922 }
923
924 Tok.setKind(tok::annot_typename);
925 setTypeAnnotation(Tok, Type.get());
926 if (SS.isNotEmpty())
927 Tok.setLocation(SS.getBeginLoc());
928 else if (TemplateKWLoc.isValid())
929 Tok.setLocation(TemplateKWLoc);
930 else
931 Tok.setLocation(TemplateNameLoc);
932 } else {
933 // Build a template-id annotation token that can be processed
934 // later.
935 Tok.setKind(tok::annot_template_id);
936 TemplateIdAnnotation *TemplateId
937 = TemplateIdAnnotation::Allocate(TemplateArgs.size(), TemplateIds);
938 TemplateId->TemplateNameLoc = TemplateNameLoc;
939 if (TemplateName.getKind() == UnqualifiedId::IK_Identifier) {
940 TemplateId->Name = TemplateName.Identifier;
941 TemplateId->Operator = OO_None;
942 } else {
943 TemplateId->Name = 0;
944 TemplateId->Operator = TemplateName.OperatorFunctionId.Operator;
945 }
946 TemplateId->SS = SS;
947 TemplateId->TemplateKWLoc = TemplateKWLoc;
948 TemplateId->Template = Template;
949 TemplateId->Kind = TNK;
950 TemplateId->LAngleLoc = LAngleLoc;
951 TemplateId->RAngleLoc = RAngleLoc;
952 ParsedTemplateArgument *Args = TemplateId->getTemplateArgs();
953 for (unsigned Arg = 0, ArgEnd = TemplateArgs.size(); Arg != ArgEnd; ++Arg)
954 Args[Arg] = ParsedTemplateArgument(TemplateArgs[Arg]);
955 Tok.setAnnotationValue(TemplateId);
956 if (TemplateKWLoc.isValid())
957 Tok.setLocation(TemplateKWLoc);
958 else
959 Tok.setLocation(TemplateNameLoc);
960 }
961
962 // Common fields for the annotation token
963 Tok.setAnnotationEndLoc(RAngleLoc);
964
965 // In case the tokens were cached, have Preprocessor replace them with the
966 // annotation token.
967 PP.AnnotateCachedTokens(Tok);
968 return false;
969 }
970
971 /// \brief Replaces a template-id annotation token with a type
972 /// annotation token.
973 ///
974 /// If there was a failure when forming the type from the template-id,
975 /// a type annotation token will still be created, but will have a
976 /// NULL type pointer to signify an error.
977 void Parser::AnnotateTemplateIdTokenAsType() {
978 assert(Tok.is(tok::annot_template_id) && "Requires template-id tokens");
979
980 TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Tok);
981 assert((TemplateId->Kind == TNK_Type_template ||
982 TemplateId->Kind == TNK_Dependent_template_name) &&
983 "Only works for type and dependent templates");
984
985 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
986 TemplateId->NumArgs);
987
988 TypeResult Type
989 = Actions.ActOnTemplateIdType(TemplateId->SS,
990 TemplateId->TemplateKWLoc,
991 TemplateId->Template,
992 TemplateId->TemplateNameLoc,
993 TemplateId->LAngleLoc,
994 TemplateArgsPtr,
995 TemplateId->RAngleLoc);
996 // Create the new "type" annotation token.
997 Tok.setKind(tok::annot_typename);
998 setTypeAnnotation(Tok, Type.isInvalid() ? ParsedType() : Type.get());
999 if (TemplateId->SS.isNotEmpty()) // it was a C++ qualified type name.
1000 Tok.setLocation(TemplateId->SS.getBeginLoc());
1001 // End location stays the same
1002
1003 // Replace the template-id annotation token, and possible the scope-specifier
1004 // that precedes it, with the typename annotation token.
1005 PP.AnnotateCachedTokens(Tok);
1006 }
1007
1008 /// \brief Determine whether the given token can end a template argument.
1009 static bool isEndOfTemplateArgument(Token Tok) {
1010 return Tok.is(tok::comma) || Tok.is(tok::greater) ||
1011 Tok.is(tok::greatergreater);
1012 }
1013
1014 /// \brief Parse a C++ template template argument.
1015 ParsedTemplateArgument Parser::ParseTemplateTemplateArgument() {
1016 if (!Tok.is(tok::identifier) && !Tok.is(tok::coloncolon) &&
1017 !Tok.is(tok::annot_cxxscope))
1018 return ParsedTemplateArgument();
1019
1020 // C++0x [temp.arg.template]p1:
1021 // A template-argument for a template template-parameter shall be the name
1022 // of a class template or an alias template, expressed as id-expression.
1023 //
1024 // We parse an id-expression that refers to a class template or alias
1025 // template. The grammar we parse is:
1026 //
1027 // nested-name-specifier[opt] template[opt] identifier ...[opt]
1028 //
1029 // followed by a token that terminates a template argument, such as ',',
1030 // '>', or (in some cases) '>>'.
1031 CXXScopeSpec SS; // nested-name-specifier, if present
1032 ParseOptionalCXXScopeSpecifier(SS, ParsedType(),
1033 /*EnteringContext=*/false);
1034
1035 ParsedTemplateArgument Result;
1036 SourceLocation EllipsisLoc;
1037 if (SS.isSet() && Tok.is(tok::kw_template)) {
1038 // Parse the optional 'template' keyword following the
1039 // nested-name-specifier.
1040 SourceLocation TemplateKWLoc = ConsumeToken();
1041
1042 if (Tok.is(tok::identifier)) {
1043 // We appear to have a dependent template name.
1044 UnqualifiedId Name;
1045 Name.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1046 ConsumeToken(); // the identifier
1047
1048 // Parse the ellipsis.
1049 if (Tok.is(tok::ellipsis))
1050 EllipsisLoc = ConsumeToken();
1051
1052 // If the next token signals the end of a template argument,
1053 // then we have a dependent template name that could be a template
1054 // template argument.
1055 TemplateTy Template;
1056 if (isEndOfTemplateArgument(Tok) &&
1057 Actions.ActOnDependentTemplateName(getCurScope(),
1058 SS, TemplateKWLoc, Name,
1059 /*ObjectType=*/ ParsedType(),
1060 /*EnteringContext=*/false,
1061 Template))
1062 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation);
1063 }
1064 } else if (Tok.is(tok::identifier)) {
1065 // We may have a (non-dependent) template name.
1066 TemplateTy Template;
1067 UnqualifiedId Name;
1068 Name.setIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1069 ConsumeToken(); // the identifier
1070
1071 // Parse the ellipsis.
1072 if (Tok.is(tok::ellipsis))
1073 EllipsisLoc = ConsumeToken();
1074
1075 if (isEndOfTemplateArgument(Tok)) {
1076 bool MemberOfUnknownSpecialization;
1077 TemplateNameKind TNK = Actions.isTemplateName(getCurScope(), SS,
1078 /*hasTemplateKeyword=*/false,
1079 Name,
1080 /*ObjectType=*/ ParsedType(),
1081 /*EnteringContext=*/false,
1082 Template,
1083 MemberOfUnknownSpecialization);
1084 if (TNK == TNK_Dependent_template_name || TNK == TNK_Type_template) {
1085 // We have an id-expression that refers to a class template or
1086 // (C++0x) alias template.
1087 Result = ParsedTemplateArgument(SS, Template, Name.StartLocation);
1088 }
1089 }
1090 }
1091
1092 // If this is a pack expansion, build it as such.
1093 if (EllipsisLoc.isValid() && !Result.isInvalid())
1094 Result = Actions.ActOnPackExpansion(Result, EllipsisLoc);
1095
1096 return Result;
1097 }
1098
1099 /// ParseTemplateArgument - Parse a C++ template argument (C++ [temp.names]).
1100 ///
1101 /// template-argument: [C++ 14.2]
1102 /// constant-expression
1103 /// type-id
1104 /// id-expression
1105 ParsedTemplateArgument Parser::ParseTemplateArgument() {
1106 // C++ [temp.arg]p2:
1107 // In a template-argument, an ambiguity between a type-id and an
1108 // expression is resolved to a type-id, regardless of the form of
1109 // the corresponding template-parameter.
1110 //
1111 // Therefore, we initially try to parse a type-id.
1112 if (isCXXTypeId(TypeIdAsTemplateArgument)) {
1113 SourceLocation Loc = Tok.getLocation();
1114 TypeResult TypeArg = ParseTypeName(/*Range=*/0,
1115 Declarator::TemplateTypeArgContext);
1116 if (TypeArg.isInvalid())
1117 return ParsedTemplateArgument();
1118
1119 return ParsedTemplateArgument(ParsedTemplateArgument::Type,
1120 TypeArg.get().getAsOpaquePtr(),
1121 Loc);
1122 }
1123
1124 // Try to parse a template template argument.
1125 {
1126 TentativeParsingAction TPA(*this);
1127
1128 ParsedTemplateArgument TemplateTemplateArgument
1129 = ParseTemplateTemplateArgument();
1130 if (!TemplateTemplateArgument.isInvalid()) {
1131 TPA.Commit();
1132 return TemplateTemplateArgument;
1133 }
1134
1135 // Revert this tentative parse to parse a non-type template argument.
1136 TPA.Revert();
1137 }
1138
1139 // Parse a non-type template argument.
1140 SourceLocation Loc = Tok.getLocation();
1141 ExprResult ExprArg = ParseConstantExpression(MaybeTypeCast);
1142 if (ExprArg.isInvalid() || !ExprArg.get())
1143 return ParsedTemplateArgument();
1144
1145 return ParsedTemplateArgument(ParsedTemplateArgument::NonType,
1146 ExprArg.release(), Loc);
1147 }
1148
1149 /// \brief Determine whether the current tokens can only be parsed as a
1150 /// template argument list (starting with the '<') and never as a '<'
1151 /// expression.
1152 bool Parser::IsTemplateArgumentList(unsigned Skip) {
1153 struct AlwaysRevertAction : TentativeParsingAction {
1154 AlwaysRevertAction(Parser &P) : TentativeParsingAction(P) { }
1155 ~AlwaysRevertAction() { Revert(); }
1156 } Tentative(*this);
1157
1158 while (Skip) {
1159 ConsumeToken();
1160 --Skip;
1161 }
1162
1163 // '<'
1164 if (!Tok.is(tok::less))
1165 return false;
1166 ConsumeToken();
1167
1168 // An empty template argument list.
1169 if (Tok.is(tok::greater))
1170 return true;
1171
1172 // See whether we have declaration specifiers, which indicate a type.
1173 while (isCXXDeclarationSpecifier() == TPResult::True())
1174 ConsumeToken();
1175
1176 // If we have a '>' or a ',' then this is a template argument list.
1177 return Tok.is(tok::greater) || Tok.is(tok::comma);
1178 }
1179
1180 /// ParseTemplateArgumentList - Parse a C++ template-argument-list
1181 /// (C++ [temp.names]). Returns true if there was an error.
1182 ///
1183 /// template-argument-list: [C++ 14.2]
1184 /// template-argument
1185 /// template-argument-list ',' template-argument
1186 bool
1187 Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs) {
1188 // Template argument lists are constant-evaluation contexts.
1189 EnterExpressionEvaluationContext EvalContext(Actions,Sema::ConstantEvaluated);
1190
1191 while (true) {
1192 ParsedTemplateArgument Arg = ParseTemplateArgument();
1193 if (Tok.is(tok::ellipsis)) {
1194 SourceLocation EllipsisLoc = ConsumeToken();
1195 Arg = Actions.ActOnPackExpansion(Arg, EllipsisLoc);
1196 }
1197
1198 if (Arg.isInvalid()) {
1199 SkipUntil(tok::comma, tok::greater, StopAtSemi | StopBeforeMatch);
1200 return true;
1201 }
1202
1203 // Save this template argument.
1204 TemplateArgs.push_back(Arg);
1205
1206 // If the next token is a comma, consume it and keep reading
1207 // arguments.
1208 if (Tok.isNot(tok::comma)) break;
1209
1210 // Consume the comma.
1211 ConsumeToken();
1212 }
1213
1214 return false;
1215 }
1216
1217 /// \brief Parse a C++ explicit template instantiation
1218 /// (C++ [temp.explicit]).
1219 ///
1220 /// explicit-instantiation:
1221 /// 'extern' [opt] 'template' declaration
1222 ///
1223 /// Note that the 'extern' is a GNU extension and C++11 feature.
1224 Decl *Parser::ParseExplicitInstantiation(unsigned Context,
1225 SourceLocation ExternLoc,
1226 SourceLocation TemplateLoc,
1227 SourceLocation &DeclEnd,
1228 AccessSpecifier AS) {
1229 // This isn't really required here.
1230 ParsingDeclRAIIObject
1231 ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
1232
1233 return ParseSingleDeclarationAfterTemplate(Context,
1234 ParsedTemplateInfo(ExternLoc,
1235 TemplateLoc),
1236 ParsingTemplateParams,
1237 DeclEnd, AS);
1238 }
1239
1240 SourceRange Parser::ParsedTemplateInfo::getSourceRange() const {
1241 if (TemplateParams)
1242 return getTemplateParamsRange(TemplateParams->data(),
1243 TemplateParams->size());
1244
1245 SourceRange R(TemplateLoc);
1246 if (ExternLoc.isValid())
1247 R.setBegin(ExternLoc);
1248 return R;
1249 }
1250
1251 void Parser::LateTemplateParserCallback(void *P, LateParsedTemplate &LPT) {
1252 ((Parser *)P)->ParseLateTemplatedFuncDef(LPT);
1253 }
1254
1255 /// \brief Late parse a C++ function template in Microsoft mode.
1256 void Parser::ParseLateTemplatedFuncDef(LateParsedTemplate &LPT) {
1257 if (!LPT.D)
1258 return;
1259
1260 // Get the FunctionDecl.
1261 FunctionTemplateDecl *FunTmplD = dyn_cast<FunctionTemplateDecl>(LPT.D);
1262 FunctionDecl *FunD =
1263 FunTmplD ? FunTmplD->getTemplatedDecl() : cast<FunctionDecl>(LPT.D);
1264 // Track template parameter depth.
1265 TemplateParameterDepthRAII CurTemplateDepthTracker(TemplateParameterDepth);
1266
1267 // To restore the context after late parsing.
1268 Sema::ContextRAII GlobalSavedContext(Actions, Actions.CurContext);
1269
1270 SmallVector<ParseScope*, 4> TemplateParamScopeStack;
1271
1272 // Get the list of DeclContexts to reenter.
1273 SmallVector<DeclContext*, 4> DeclContextsToReenter;
1274 DeclContext *DD = FunD->getLexicalParent();
1275 while (DD && !DD->isTranslationUnit()) {
1276 DeclContextsToReenter.push_back(DD);
1277 DD = DD->getLexicalParent();
1278 }
1279
1280 // Reenter template scopes from outermost to innermost.
1281 SmallVectorImpl<DeclContext *>::reverse_iterator II =
1282 DeclContextsToReenter.rbegin();
1283 for (; II != DeclContextsToReenter.rend(); ++II) {
1284 if (ClassTemplatePartialSpecializationDecl *MD =
1285 dyn_cast_or_null<ClassTemplatePartialSpecializationDecl>(*II)) {
1286 TemplateParamScopeStack.push_back(
1287 new ParseScope(this, Scope::TemplateParamScope));
1288 Actions.ActOnReenterTemplateScope(getCurScope(), MD);
1289 ++CurTemplateDepthTracker;
1290 } else if (CXXRecordDecl *MD = dyn_cast_or_null<CXXRecordDecl>(*II)) {
1291 bool IsClassTemplate = MD->getDescribedClassTemplate() != 0;
1292 TemplateParamScopeStack.push_back(
1293 new ParseScope(this, Scope::TemplateParamScope,
1294 /*ManageScope*/IsClassTemplate));
1295 Actions.ActOnReenterTemplateScope(getCurScope(),
1296 MD->getDescribedClassTemplate());
1297 if (IsClassTemplate)
1298 ++CurTemplateDepthTracker;
1299 }
1300 TemplateParamScopeStack.push_back(new ParseScope(this, Scope::DeclScope));
1301 Actions.PushDeclContext(Actions.getCurScope(), *II);
1302 }
1303 TemplateParamScopeStack.push_back(
1304 new ParseScope(this, Scope::TemplateParamScope));
1305
1306 DeclaratorDecl *Declarator = dyn_cast<DeclaratorDecl>(FunD);
1307 if (Declarator && Declarator->getNumTemplateParameterLists() != 0) {
1308 Actions.ActOnReenterDeclaratorTemplateScope(getCurScope(), Declarator);
1309 ++CurTemplateDepthTracker;
1310 }
1311 Actions.ActOnReenterTemplateScope(getCurScope(), LPT.D);
1312 ++CurTemplateDepthTracker;
1313
1314 assert(!LPT.Toks.empty() && "Empty body!");
1315
1316 // Append the current token at the end of the new token stream so that it
1317 // doesn't get lost.
1318 LPT.Toks.push_back(Tok);
1319 PP.EnterTokenStream(LPT.Toks.data(), LPT.Toks.size(), true, false);
1320
1321 // Consume the previously pushed token.
1322 ConsumeAnyToken(/*ConsumeCodeCompletionTok=*/true);
1323 assert((Tok.is(tok::l_brace) || Tok.is(tok::colon) || Tok.is(tok::kw_try))
1324 && "Inline method not starting with '{', ':' or 'try'");
1325
1326 // Parse the method body. Function body parsing code is similar enough
1327 // to be re-used for method bodies as well.
1328 ParseScope FnScope(this, Scope::FnScope|Scope::DeclScope);
1329
1330 // Recreate the containing function DeclContext.
1331 Sema::ContextRAII FunctionSavedContext(Actions, Actions.getContainingDC(FunD));
1332
1333 Actions.ActOnStartOfFunctionDef(getCurScope(), FunD);
1334
1335 if (Tok.is(tok::kw_try)) {
1336 ParseFunctionTryBlock(LPT.D, FnScope);
1337 } else {
1338 if (Tok.is(tok::colon))
1339 ParseConstructorInitializer(LPT.D);
1340 else
1341 Actions.ActOnDefaultCtorInitializers(LPT.D);
1342
1343 if (Tok.is(tok::l_brace)) {
1344 assert((!FunTmplD || FunTmplD->getTemplateParameters()->getDepth() <
1345 TemplateParameterDepth) &&
1346 "TemplateParameterDepth should be greater than the depth of "
1347 "current template being instantiated!");
1348 ParseFunctionStatementBody(LPT.D, FnScope);
1349 Actions.UnmarkAsLateParsedTemplate(FunD);
1350 } else
1351 Actions.ActOnFinishFunctionBody(LPT.D, 0);
1352 }
1353
1354 // Exit scopes.
1355 FnScope.Exit();
1356 SmallVectorImpl<ParseScope *>::reverse_iterator I =
1357 TemplateParamScopeStack.rbegin();
1358 for (; I != TemplateParamScopeStack.rend(); ++I)
1359 delete *I;
1360 }
1361
1362 /// \brief Lex a delayed template function for late parsing.
1363 void Parser::LexTemplateFunctionForLateParsing(CachedTokens &Toks) {
1364 tok::TokenKind kind = Tok.getKind();
1365 if (!ConsumeAndStoreFunctionPrologue(Toks)) {
1366 // Consume everything up to (and including) the matching right brace.
1367 ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
1368 }
1369
1370 // If we're in a function-try-block, we need to store all the catch blocks.
1371 if (kind == tok::kw_try) {
1372 while (Tok.is(tok::kw_catch)) {
1373 ConsumeAndStoreUntil(tok::l_brace, Toks, /*StopAtSemi=*/false);
1374 ConsumeAndStoreUntil(tok::r_brace, Toks, /*StopAtSemi=*/false);
1375 }
1376 }
1377 }