ParseDecl.cpp revision 4bdd91c09fd59e0c154d759288beff300e31e1d0 
1//===--- ParseDecl.cpp - Declaration 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 the Declaration portions of the Parser interfaces.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Parse/Parser.h"
15#include "clang/Basic/Diagnostic.h"
16#include "clang/Parse/Scope.h"
17#include "ExtensionRAIIObject.h"
18#include "AstGuard.h"
19#include "llvm/ADT/SmallSet.h"
20using namespace clang;
21
22//===----------------------------------------------------------------------===//
23// C99 6.7: Declarations.
24//===----------------------------------------------------------------------===//
25
26/// ParseTypeName
27///       type-name: [C99 6.7.6]
28///         specifier-qualifier-list abstract-declarator[opt]
29///
30/// Called type-id in C++.
31/// CXXNewMode is a special flag used by the parser of C++ new-expressions. It
32/// is simply passed on to ActOnTypeName.
33Parser::TypeTy *Parser::ParseTypeName(bool CXXNewMode) {
34  // Parse the common declaration-specifiers piece.
35  DeclSpec DS;
36  ParseSpecifierQualifierList(DS);
37
38  // Parse the abstract-declarator, if present.
39  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
40  ParseDeclarator(DeclaratorInfo);
41
42  return Actions.ActOnTypeName(CurScope, DeclaratorInfo, CXXNewMode).Val;
43}
44
45/// ParseAttributes - Parse a non-empty attributes list.
46///
47/// [GNU] attributes:
48///         attribute
49///         attributes attribute
50///
51/// [GNU]  attribute:
52///          '__attribute__' '(' '(' attribute-list ')' ')'
53///
54/// [GNU]  attribute-list:
55///          attrib
56///          attribute_list ',' attrib
57///
58/// [GNU]  attrib:
59///          empty
60///          attrib-name
61///          attrib-name '(' identifier ')'
62///          attrib-name '(' identifier ',' nonempty-expr-list ')'
63///          attrib-name '(' argument-expression-list [C99 6.5.2] ')'
64///
65/// [GNU]  attrib-name:
66///          identifier
67///          typespec
68///          typequal
69///          storageclass
70///
71/// FIXME: The GCC grammar/code for this construct implies we need two
72/// token lookahead. Comment from gcc: "If they start with an identifier
73/// which is followed by a comma or close parenthesis, then the arguments
74/// start with that identifier; otherwise they are an expression list."
75///
76/// At the moment, I am not doing 2 token lookahead. I am also unaware of
77/// any attributes that don't work (based on my limited testing). Most
78/// attributes are very simple in practice. Until we find a bug, I don't see
79/// a pressing need to implement the 2 token lookahead.
80
81AttributeList *Parser::ParseAttributes() {
82  assert(Tok.is(tok::kw___attribute) && "Not an attribute list!");
83
84  AttributeList *CurrAttr = 0;
85
86  while (Tok.is(tok::kw___attribute)) {
87    ConsumeToken();
88    if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after,
89                         "attribute")) {
90      SkipUntil(tok::r_paren, true); // skip until ) or ;
91      return CurrAttr;
92    }
93    if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after, "(")) {
94      SkipUntil(tok::r_paren, true); // skip until ) or ;
95      return CurrAttr;
96    }
97    // Parse the attribute-list. e.g. __attribute__(( weak, alias("__f") ))
98    while (Tok.is(tok::identifier) || isDeclarationSpecifier() ||
99           Tok.is(tok::comma)) {
100
101      if (Tok.is(tok::comma)) {
102        // allows for empty/non-empty attributes. ((__vector_size__(16),,,,))
103        ConsumeToken();
104        continue;
105      }
106      // we have an identifier or declaration specifier (const, int, etc.)
107      IdentifierInfo *AttrName = Tok.getIdentifierInfo();
108      SourceLocation AttrNameLoc = ConsumeToken();
109
110      // check if we have a "paramterized" attribute
111      if (Tok.is(tok::l_paren)) {
112        ConsumeParen(); // ignore the left paren loc for now
113
114        if (Tok.is(tok::identifier)) {
115          IdentifierInfo *ParmName = Tok.getIdentifierInfo();
116          SourceLocation ParmLoc = ConsumeToken();
117
118          if (Tok.is(tok::r_paren)) {
119            // __attribute__(( mode(byte) ))
120            ConsumeParen(); // ignore the right paren loc for now
121            CurrAttr = new AttributeList(AttrName, AttrNameLoc,
122                                         ParmName, ParmLoc, 0, 0, CurrAttr);
123          } else if (Tok.is(tok::comma)) {
124            ConsumeToken();
125            // __attribute__(( format(printf, 1, 2) ))
126            ExprVector ArgExprs(Actions);
127            bool ArgExprsOk = true;
128
129            // now parse the non-empty comma separated list of expressions
130            while (1) {
131              ExprResult ArgExpr = ParseAssignmentExpression();
132              if (ArgExpr.isInvalid) {
133                ArgExprsOk = false;
134                SkipUntil(tok::r_paren);
135                break;
136              } else {
137                ArgExprs.push_back(ArgExpr.Val);
138              }
139              if (Tok.isNot(tok::comma))
140                break;
141              ConsumeToken(); // Eat the comma, move to the next argument
142            }
143            if (ArgExprsOk && Tok.is(tok::r_paren)) {
144              ConsumeParen(); // ignore the right paren loc for now
145              CurrAttr = new AttributeList(AttrName, AttrNameLoc, ParmName,
146                           ParmLoc, ArgExprs.take(), ArgExprs.size(), CurrAttr);
147            }
148          }
149        } else { // not an identifier
150          // parse a possibly empty comma separated list of expressions
151          if (Tok.is(tok::r_paren)) {
152            // __attribute__(( nonnull() ))
153            ConsumeParen(); // ignore the right paren loc for now
154            CurrAttr = new AttributeList(AttrName, AttrNameLoc,
155                                         0, SourceLocation(), 0, 0, CurrAttr);
156          } else {
157            // __attribute__(( aligned(16) ))
158            ExprVector ArgExprs(Actions);
159            bool ArgExprsOk = true;
160
161            // now parse the list of expressions
162            while (1) {
163              ExprResult ArgExpr = ParseAssignmentExpression();
164              if (ArgExpr.isInvalid) {
165                ArgExprsOk = false;
166                SkipUntil(tok::r_paren);
167                break;
168              } else {
169                ArgExprs.push_back(ArgExpr.Val);
170              }
171              if (Tok.isNot(tok::comma))
172                break;
173              ConsumeToken(); // Eat the comma, move to the next argument
174            }
175            // Match the ')'.
176            if (ArgExprsOk && Tok.is(tok::r_paren)) {
177              ConsumeParen(); // ignore the right paren loc for now
178              CurrAttr = new AttributeList(AttrName, AttrNameLoc, 0,
179                           SourceLocation(), ArgExprs.take(), ArgExprs.size(),
180                           CurrAttr);
181            }
182          }
183        }
184      } else {
185        CurrAttr = new AttributeList(AttrName, AttrNameLoc,
186                                     0, SourceLocation(), 0, 0, CurrAttr);
187      }
188    }
189    if (ExpectAndConsume(tok::r_paren, diag::err_expected_rparen))
190      SkipUntil(tok::r_paren, false);
191    if (ExpectAndConsume(tok::r_paren, diag::err_expected_rparen))
192      SkipUntil(tok::r_paren, false);
193  }
194  return CurrAttr;
195}
196
197/// ParseDeclaration - Parse a full 'declaration', which consists of
198/// declaration-specifiers, some number of declarators, and a semicolon.
199/// 'Context' should be a Declarator::TheContext value.
200///
201///       declaration: [C99 6.7]
202///         block-declaration ->
203///           simple-declaration
204///           others                   [FIXME]
205/// [C++]   namespace-definition
206///         others... [FIXME]
207///
208Parser::DeclTy *Parser::ParseDeclaration(unsigned Context) {
209  switch (Tok.getKind()) {
210  case tok::kw_namespace:
211    return ParseNamespace(Context);
212  default:
213    return ParseSimpleDeclaration(Context);
214  }
215}
216
217///       simple-declaration: [C99 6.7: declaration] [C++ 7p1: dcl.dcl]
218///         declaration-specifiers init-declarator-list[opt] ';'
219///[C90/C++]init-declarator-list ';'                             [TODO]
220/// [OMP]   threadprivate-directive                              [TODO]
221Parser::DeclTy *Parser::ParseSimpleDeclaration(unsigned Context) {
222  // Parse the common declaration-specifiers piece.
223  DeclSpec DS;
224  ParseDeclarationSpecifiers(DS);
225
226  // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
227  // declaration-specifiers init-declarator-list[opt] ';'
228  if (Tok.is(tok::semi)) {
229    ConsumeToken();
230    return Actions.ParsedFreeStandingDeclSpec(CurScope, DS);
231  }
232
233  Declarator DeclaratorInfo(DS, (Declarator::TheContext)Context);
234  ParseDeclarator(DeclaratorInfo);
235
236  return ParseInitDeclaratorListAfterFirstDeclarator(DeclaratorInfo);
237}
238
239
240/// ParseInitDeclaratorListAfterFirstDeclarator - Parse 'declaration' after
241/// parsing 'declaration-specifiers declarator'.  This method is split out this
242/// way to handle the ambiguity between top-level function-definitions and
243/// declarations.
244///
245///       init-declarator-list: [C99 6.7]
246///         init-declarator
247///         init-declarator-list ',' init-declarator
248///       init-declarator: [C99 6.7]
249///         declarator
250///         declarator '=' initializer
251/// [GNU]   declarator simple-asm-expr[opt] attributes[opt]
252/// [GNU]   declarator simple-asm-expr[opt] attributes[opt] '=' initializer
253/// [C++]   declarator initializer[opt]
254///
255/// [C++] initializer:
256/// [C++]   '=' initializer-clause
257/// [C++]   '(' expression-list ')'
258///
259Parser::DeclTy *Parser::
260ParseInitDeclaratorListAfterFirstDeclarator(Declarator &D) {
261
262  // Declarators may be grouped together ("int X, *Y, Z();").  Provide info so
263  // that they can be chained properly if the actions want this.
264  Parser::DeclTy *LastDeclInGroup = 0;
265
266  // At this point, we know that it is not a function definition.  Parse the
267  // rest of the init-declarator-list.
268  while (1) {
269    // If a simple-asm-expr is present, parse it.
270    if (Tok.is(tok::kw_asm)) {
271      ExprResult AsmLabel = ParseSimpleAsm();
272      if (AsmLabel.isInvalid) {
273        SkipUntil(tok::semi);
274        return 0;
275      }
276
277      D.setAsmLabel(AsmLabel.Val);
278    }
279
280    // If attributes are present, parse them.
281    if (Tok.is(tok::kw___attribute))
282      D.AddAttributes(ParseAttributes());
283
284    // Inform the current actions module that we just parsed this declarator.
285    LastDeclInGroup = Actions.ActOnDeclarator(CurScope, D, LastDeclInGroup);
286
287    // Parse declarator '=' initializer.
288    if (Tok.is(tok::equal)) {
289      ConsumeToken();
290      ExprResult Init = ParseInitializer();
291      if (Init.isInvalid) {
292        SkipUntil(tok::semi);
293        return 0;
294      }
295      Actions.AddInitializerToDecl(LastDeclInGroup, Init.Val);
296    } else if (Tok.is(tok::l_paren)) {
297      // Parse C++ direct initializer: '(' expression-list ')'
298      SourceLocation LParenLoc = ConsumeParen();
299      ExprVector Exprs(Actions);
300      CommaLocsTy CommaLocs;
301
302      bool InvalidExpr = false;
303      if (ParseExpressionList(Exprs, CommaLocs)) {
304        SkipUntil(tok::r_paren);
305        InvalidExpr = true;
306      }
307      // Match the ')'.
308      SourceLocation RParenLoc = MatchRHSPunctuation(tok::r_paren, LParenLoc);
309
310      if (!InvalidExpr) {
311        assert(!Exprs.empty() && Exprs.size()-1 == CommaLocs.size() &&
312               "Unexpected number of commas!");
313        Actions.AddCXXDirectInitializerToDecl(LastDeclInGroup, LParenLoc,
314                                              Exprs.take(), Exprs.size(),
315                                              &CommaLocs[0], RParenLoc);
316      }
317    } else {
318      Actions.ActOnUninitializedDecl(LastDeclInGroup);
319    }
320
321    // If we don't have a comma, it is either the end of the list (a ';') or an
322    // error, bail out.
323    if (Tok.isNot(tok::comma))
324      break;
325
326    // Consume the comma.
327    ConsumeToken();
328
329    // Parse the next declarator.
330    D.clear();
331
332    // Accept attributes in an init-declarator.  In the first declarator in a
333    // declaration, these would be part of the declspec.  In subsequent
334    // declarators, they become part of the declarator itself, so that they
335    // don't apply to declarators after *this* one.  Examples:
336    //    short __attribute__((common)) var;    -> declspec
337    //    short var __attribute__((common));    -> declarator
338    //    short x, __attribute__((common)) var;    -> declarator
339    if (Tok.is(tok::kw___attribute))
340      D.AddAttributes(ParseAttributes());
341
342    ParseDeclarator(D);
343  }
344
345  if (Tok.is(tok::semi)) {
346    ConsumeToken();
347    return Actions.FinalizeDeclaratorGroup(CurScope, LastDeclInGroup);
348  }
349  // If this is an ObjC2 for-each loop, this is a successful declarator
350  // parse.  The syntax for these looks like:
351  // 'for' '(' declaration 'in' expr ')' statement
352  if (D.getContext()  == Declarator::ForContext && isTokIdentifier_in()) {
353    return Actions.FinalizeDeclaratorGroup(CurScope, LastDeclInGroup);
354  }
355  Diag(Tok, diag::err_parse_error);
356  // Skip to end of block or statement
357  SkipUntil(tok::r_brace, true, true);
358  if (Tok.is(tok::semi))
359    ConsumeToken();
360  return 0;
361}
362
363/// ParseSpecifierQualifierList
364///        specifier-qualifier-list:
365///          type-specifier specifier-qualifier-list[opt]
366///          type-qualifier specifier-qualifier-list[opt]
367/// [GNU]    attributes     specifier-qualifier-list[opt]
368///
369void Parser::ParseSpecifierQualifierList(DeclSpec &DS) {
370  /// specifier-qualifier-list is a subset of declaration-specifiers.  Just
371  /// parse declaration-specifiers and complain about extra stuff.
372  ParseDeclarationSpecifiers(DS);
373
374  // Validate declspec for type-name.
375  unsigned Specs = DS.getParsedSpecifiers();
376  if (Specs == DeclSpec::PQ_None && !DS.getNumProtocolQualifiers())
377    Diag(Tok, diag::err_typename_requires_specqual);
378
379  // Issue diagnostic and remove storage class if present.
380  if (Specs & DeclSpec::PQ_StorageClassSpecifier) {
381    if (DS.getStorageClassSpecLoc().isValid())
382      Diag(DS.getStorageClassSpecLoc(),diag::err_typename_invalid_storageclass);
383    else
384      Diag(DS.getThreadSpecLoc(), diag::err_typename_invalid_storageclass);
385    DS.ClearStorageClassSpecs();
386  }
387
388  // Issue diagnostic and remove function specfier if present.
389  if (Specs & DeclSpec::PQ_FunctionSpecifier) {
390    if (DS.isInlineSpecified())
391      Diag(DS.getInlineSpecLoc(), diag::err_typename_invalid_functionspec);
392    if (DS.isVirtualSpecified())
393      Diag(DS.getVirtualSpecLoc(), diag::err_typename_invalid_functionspec);
394    if (DS.isExplicitSpecified())
395      Diag(DS.getExplicitSpecLoc(), diag::err_typename_invalid_functionspec);
396    DS.ClearFunctionSpecs();
397  }
398}
399
400/// ParseDeclarationSpecifiers
401///       declaration-specifiers: [C99 6.7]
402///         storage-class-specifier declaration-specifiers[opt]
403///         type-specifier declaration-specifiers[opt]
404/// [C99]   function-specifier declaration-specifiers[opt]
405/// [GNU]   attributes declaration-specifiers[opt]
406///
407///       storage-class-specifier: [C99 6.7.1]
408///         'typedef'
409///         'extern'
410///         'static'
411///         'auto'
412///         'register'
413/// [C++]   'mutable'
414/// [GNU]   '__thread'
415///       function-specifier: [C99 6.7.4]
416/// [C99]   'inline'
417/// [C++]   'virtual'
418/// [C++]   'explicit'
419///
420void Parser::ParseDeclarationSpecifiers(DeclSpec &DS) {
421  DS.SetRangeStart(Tok.getLocation());
422  while (1) {
423    int isInvalid = false;
424    const char *PrevSpec = 0;
425    SourceLocation Loc = Tok.getLocation();
426
427    // Only annotate C++ scope. Allow class-name as an identifier in case
428    // it's a constructor.
429    if (getLang().CPlusPlus)
430      TryAnnotateCXXScopeToken();
431
432    switch (Tok.getKind()) {
433    default:
434      // Try to parse a type-specifier; if we found one, continue.
435      if (MaybeParseTypeSpecifier(DS, isInvalid, PrevSpec))
436        continue;
437
438    DoneWithDeclSpec:
439      // If this is not a declaration specifier token, we're done reading decl
440      // specifiers.  First verify that DeclSpec's are consistent.
441      DS.Finish(Diags, PP.getSourceManager(), getLang());
442      return;
443
444    case tok::annot_cxxscope: {
445      if (DS.hasTypeSpecifier())
446        goto DoneWithDeclSpec;
447
448      // We are looking for a qualified typename.
449      if (NextToken().isNot(tok::identifier))
450        goto DoneWithDeclSpec;
451
452      CXXScopeSpec SS;
453      SS.setScopeRep(Tok.getAnnotationValue());
454      SS.setRange(Tok.getAnnotationRange());
455
456      // If the next token is the name of the class type that the C++ scope
457      // denotes, followed by a '(', then this is a constructor declaration.
458      // We're done with the decl-specifiers.
459      if (Actions.isCurrentClassName(*NextToken().getIdentifierInfo(),
460                                     CurScope, &SS) &&
461          GetLookAheadToken(2).is(tok::l_paren))
462        goto DoneWithDeclSpec;
463
464      TypeTy *TypeRep = Actions.isTypeName(*NextToken().getIdentifierInfo(),
465                                           CurScope, &SS);
466      if (TypeRep == 0)
467        goto DoneWithDeclSpec;
468
469      ConsumeToken(); // The C++ scope.
470
471      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typedef, Loc, PrevSpec,
472                                     TypeRep);
473      if (isInvalid)
474        break;
475
476      DS.SetRangeEnd(Tok.getLocation());
477      ConsumeToken(); // The typename.
478
479      continue;
480    }
481
482      // typedef-name
483    case tok::identifier: {
484      // This identifier can only be a typedef name if we haven't already seen
485      // a type-specifier.  Without this check we misparse:
486      //  typedef int X; struct Y { short X; };  as 'short int'.
487      if (DS.hasTypeSpecifier())
488        goto DoneWithDeclSpec;
489
490      // It has to be available as a typedef too!
491      TypeTy *TypeRep = Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope);
492      if (TypeRep == 0)
493        goto DoneWithDeclSpec;
494
495      // C++: If the identifier is actually the name of the class type
496      // being defined and the next token is a '(', then this is a
497      // constructor declaration. We're done with the decl-specifiers
498      // and will treat this token as an identifier.
499      if (getLang().CPlusPlus &&
500          CurScope->isCXXClassScope() &&
501          Actions.isCurrentClassName(*Tok.getIdentifierInfo(), CurScope) &&
502          NextToken().getKind() == tok::l_paren)
503        goto DoneWithDeclSpec;
504
505      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typedef, Loc, PrevSpec,
506                                     TypeRep);
507      if (isInvalid)
508        break;
509
510      DS.SetRangeEnd(Tok.getLocation());
511      ConsumeToken(); // The identifier
512
513      // Objective-C supports syntax of the form 'id<proto1,proto2>' where 'id'
514      // is a specific typedef and 'itf<proto1,proto2>' where 'itf' is an
515      // Objective-C interface.  If we don't have Objective-C or a '<', this is
516      // just a normal reference to a typedef name.
517      if (!Tok.is(tok::less) || !getLang().ObjC1)
518        continue;
519
520      SourceLocation EndProtoLoc;
521      llvm::SmallVector<DeclTy *, 8> ProtocolDecl;
522      ParseObjCProtocolReferences(ProtocolDecl, false, EndProtoLoc);
523      DS.setProtocolQualifiers(&ProtocolDecl[0], ProtocolDecl.size());
524
525      DS.SetRangeEnd(EndProtoLoc);
526
527      // Need to support trailing type qualifiers (e.g. "id<p> const").
528      // If a type specifier follows, it will be diagnosed elsewhere.
529      continue;
530    }
531    // GNU attributes support.
532    case tok::kw___attribute:
533      DS.AddAttributes(ParseAttributes());
534      continue;
535
536    // storage-class-specifier
537    case tok::kw_typedef:
538      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_typedef, Loc, PrevSpec);
539      break;
540    case tok::kw_extern:
541      if (DS.isThreadSpecified())
542        Diag(Tok, diag::ext_thread_before) << "extern";
543      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_extern, Loc, PrevSpec);
544      break;
545    case tok::kw___private_extern__:
546      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_private_extern, Loc,
547                                         PrevSpec);
548      break;
549    case tok::kw_static:
550      if (DS.isThreadSpecified())
551        Diag(Tok, diag::ext_thread_before) << "static";
552      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_static, Loc, PrevSpec);
553      break;
554    case tok::kw_auto:
555      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_auto, Loc, PrevSpec);
556      break;
557    case tok::kw_register:
558      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_register, Loc, PrevSpec);
559      break;
560    case tok::kw_mutable:
561      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_mutable, Loc, PrevSpec);
562      break;
563    case tok::kw___thread:
564      isInvalid = DS.SetStorageClassSpecThread(Loc, PrevSpec)*2;
565      break;
566
567      continue;
568
569    // function-specifier
570    case tok::kw_inline:
571      isInvalid = DS.SetFunctionSpecInline(Loc, PrevSpec);
572      break;
573
574    case tok::kw_virtual:
575      isInvalid = DS.SetFunctionSpecVirtual(Loc, PrevSpec);
576      break;
577
578    case tok::kw_explicit:
579      isInvalid = DS.SetFunctionSpecExplicit(Loc, PrevSpec);
580      break;
581
582    case tok::less:
583      // GCC ObjC supports types like "<SomeProtocol>" as a synonym for
584      // "id<SomeProtocol>".  This is hopelessly old fashioned and dangerous,
585      // but we support it.
586      if (DS.hasTypeSpecifier() || !getLang().ObjC1)
587        goto DoneWithDeclSpec;
588
589      {
590        SourceLocation EndProtoLoc;
591        llvm::SmallVector<DeclTy *, 8> ProtocolDecl;
592        ParseObjCProtocolReferences(ProtocolDecl, false, EndProtoLoc);
593        DS.setProtocolQualifiers(&ProtocolDecl[0], ProtocolDecl.size());
594        DS.SetRangeEnd(EndProtoLoc);
595
596        Diag(Loc, diag::warn_objc_protocol_qualifier_missing_id)
597          << SourceRange(Loc, EndProtoLoc);
598        // Need to support trailing type qualifiers (e.g. "id<p> const").
599        // If a type specifier follows, it will be diagnosed elsewhere.
600        continue;
601      }
602    }
603    // If the specifier combination wasn't legal, issue a diagnostic.
604    if (isInvalid) {
605      assert(PrevSpec && "Method did not return previous specifier!");
606      // Pick between error or extwarn.
607      unsigned DiagID = isInvalid == 1 ? diag::err_invalid_decl_spec_combination
608                                       : diag::ext_duplicate_declspec;
609      Diag(Tok, DiagID) << PrevSpec;
610    }
611    DS.SetRangeEnd(Tok.getLocation());
612    ConsumeToken();
613  }
614}
615/// MaybeParseTypeSpecifier - Try to parse a single type-specifier. We
616/// primarily follow the C++ grammar with additions for C99 and GNU,
617/// which together subsume the C grammar. Note that the C++
618/// type-specifier also includes the C type-qualifier (for const,
619/// volatile, and C99 restrict). Returns true if a type-specifier was
620/// found (and parsed), false otherwise.
621///
622///       type-specifier: [C++ 7.1.5]
623///         simple-type-specifier
624///         class-specifier
625///         enum-specifier
626///         elaborated-type-specifier  [TODO]
627///         cv-qualifier
628///
629///       cv-qualifier: [C++ 7.1.5.1]
630///         'const'
631///         'volatile'
632/// [C99]   'restrict'
633///
634///       simple-type-specifier: [ C++ 7.1.5.2]
635///         '::'[opt] nested-name-specifier[opt] type-name [TODO]
636///         '::'[opt] nested-name-specifier 'template' template-id [TODO]
637///         'char'
638///         'wchar_t'
639///         'bool'
640///         'short'
641///         'int'
642///         'long'
643///         'signed'
644///         'unsigned'
645///         'float'
646///         'double'
647///         'void'
648/// [C99]   '_Bool'
649/// [C99]   '_Complex'
650/// [C99]   '_Imaginary'  // Removed in TC2?
651/// [GNU]   '_Decimal32'
652/// [GNU]   '_Decimal64'
653/// [GNU]   '_Decimal128'
654/// [GNU]   typeof-specifier
655/// [OBJC]  class-name objc-protocol-refs[opt]    [TODO]
656/// [OBJC]  typedef-name objc-protocol-refs[opt]  [TODO]
657bool Parser::MaybeParseTypeSpecifier(DeclSpec &DS, int& isInvalid,
658                                     const char *&PrevSpec) {
659  // Annotate typenames and C++ scope specifiers.
660  TryAnnotateTypeOrScopeToken();
661
662  SourceLocation Loc = Tok.getLocation();
663
664  switch (Tok.getKind()) {
665  // simple-type-specifier:
666  case tok::annot_qualtypename: {
667    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typedef, Loc, PrevSpec,
668                                   Tok.getAnnotationValue());
669    DS.SetRangeEnd(Tok.getAnnotationEndLoc());
670    ConsumeToken(); // The typename
671
672    // Objective-C supports syntax of the form 'id<proto1,proto2>' where 'id'
673    // is a specific typedef and 'itf<proto1,proto2>' where 'itf' is an
674    // Objective-C interface.  If we don't have Objective-C or a '<', this is
675    // just a normal reference to a typedef name.
676    if (!Tok.is(tok::less) || !getLang().ObjC1)
677      return true;
678
679    SourceLocation EndProtoLoc;
680    llvm::SmallVector<DeclTy *, 8> ProtocolDecl;
681    ParseObjCProtocolReferences(ProtocolDecl, false, EndProtoLoc);
682    DS.setProtocolQualifiers(&ProtocolDecl[0], ProtocolDecl.size());
683
684    DS.SetRangeEnd(EndProtoLoc);
685    return true;
686  }
687
688  case tok::kw_short:
689    isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec);
690    break;
691  case tok::kw_long:
692    if (DS.getTypeSpecWidth() != DeclSpec::TSW_long)
693      isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec);
694    else
695      isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_longlong, Loc, PrevSpec);
696    break;
697  case tok::kw_signed:
698    isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec);
699    break;
700  case tok::kw_unsigned:
701    isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec);
702    break;
703  case tok::kw__Complex:
704    isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_complex, Loc, PrevSpec);
705    break;
706  case tok::kw__Imaginary:
707    isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_imaginary, Loc, PrevSpec);
708    break;
709  case tok::kw_void:
710    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec);
711    break;
712  case tok::kw_char:
713    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec);
714    break;
715  case tok::kw_int:
716    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec);
717    break;
718  case tok::kw_float:
719    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec);
720    break;
721  case tok::kw_double:
722    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec);
723    break;
724  case tok::kw_wchar_t:
725    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec);
726    break;
727  case tok::kw_bool:
728  case tok::kw__Bool:
729    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec);
730    break;
731  case tok::kw__Decimal32:
732    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal32, Loc, PrevSpec);
733    break;
734  case tok::kw__Decimal64:
735    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal64, Loc, PrevSpec);
736    break;
737  case tok::kw__Decimal128:
738    isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal128, Loc, PrevSpec);
739    break;
740
741  // class-specifier:
742  case tok::kw_class:
743  case tok::kw_struct:
744  case tok::kw_union:
745    ParseClassSpecifier(DS);
746    return true;
747
748  // enum-specifier:
749  case tok::kw_enum:
750    ParseEnumSpecifier(DS);
751    return true;
752
753  // cv-qualifier:
754  case tok::kw_const:
755    isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec,
756                               getLang())*2;
757    break;
758  case tok::kw_volatile:
759    isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec,
760                               getLang())*2;
761    break;
762  case tok::kw_restrict:
763    isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec,
764                               getLang())*2;
765    break;
766
767  // GNU typeof support.
768  case tok::kw_typeof:
769    ParseTypeofSpecifier(DS);
770    return true;
771
772  default:
773    // Not a type-specifier; do nothing.
774    return false;
775  }
776
777  // If the specifier combination wasn't legal, issue a diagnostic.
778  if (isInvalid) {
779    assert(PrevSpec && "Method did not return previous specifier!");
780    // Pick between error or extwarn.
781    unsigned DiagID = isInvalid == 1 ? diag::err_invalid_decl_spec_combination
782                                     : diag::ext_duplicate_declspec;
783    Diag(Tok, DiagID) << PrevSpec;
784  }
785  DS.SetRangeEnd(Tok.getLocation());
786  ConsumeToken(); // whatever we parsed above.
787  return true;
788}
789
790/// ParseStructDeclaration - Parse a struct declaration without the terminating
791/// semicolon.
792///
793///       struct-declaration:
794///         specifier-qualifier-list struct-declarator-list
795/// [GNU]   __extension__ struct-declaration
796/// [GNU]   specifier-qualifier-list
797///       struct-declarator-list:
798///         struct-declarator
799///         struct-declarator-list ',' struct-declarator
800/// [GNU]   struct-declarator-list ',' attributes[opt] struct-declarator
801///       struct-declarator:
802///         declarator
803/// [GNU]   declarator attributes[opt]
804///         declarator[opt] ':' constant-expression
805/// [GNU]   declarator[opt] ':' constant-expression attributes[opt]
806///
807void Parser::
808ParseStructDeclaration(DeclSpec &DS,
809                       llvm::SmallVectorImpl<FieldDeclarator> &Fields) {
810  if (Tok.is(tok::kw___extension__)) {
811    // __extension__ silences extension warnings in the subexpression.
812    ExtensionRAIIObject O(Diags);  // Use RAII to do this.
813    ConsumeToken();
814    return ParseStructDeclaration(DS, Fields);
815  }
816
817  // Parse the common specifier-qualifiers-list piece.
818  SourceLocation DSStart = Tok.getLocation();
819  ParseSpecifierQualifierList(DS);
820
821  // If there are no declarators, issue a warning.
822  if (Tok.is(tok::semi)) {
823    Diag(DSStart, diag::w_no_declarators);
824    return;
825  }
826
827  // Read struct-declarators until we find the semicolon.
828  Fields.push_back(FieldDeclarator(DS));
829  while (1) {
830    FieldDeclarator &DeclaratorInfo = Fields.back();
831
832    /// struct-declarator: declarator
833    /// struct-declarator: declarator[opt] ':' constant-expression
834    if (Tok.isNot(tok::colon))
835      ParseDeclarator(DeclaratorInfo.D);
836
837    if (Tok.is(tok::colon)) {
838      ConsumeToken();
839      ExprResult Res = ParseConstantExpression();
840      if (Res.isInvalid)
841        SkipUntil(tok::semi, true, true);
842      else
843        DeclaratorInfo.BitfieldSize = Res.Val;
844    }
845
846    // If attributes exist after the declarator, parse them.
847    if (Tok.is(tok::kw___attribute))
848      DeclaratorInfo.D.AddAttributes(ParseAttributes());
849
850    // If we don't have a comma, it is either the end of the list (a ';')
851    // or an error, bail out.
852    if (Tok.isNot(tok::comma))
853      return;
854
855    // Consume the comma.
856    ConsumeToken();
857
858    // Parse the next declarator.
859    Fields.push_back(FieldDeclarator(DS));
860
861    // Attributes are only allowed on the second declarator.
862    if (Tok.is(tok::kw___attribute))
863      Fields.back().D.AddAttributes(ParseAttributes());
864  }
865}
866
867/// ParseStructUnionBody
868///       struct-contents:
869///         struct-declaration-list
870/// [EXT]   empty
871/// [GNU]   "struct-declaration-list" without terminatoring ';'
872///       struct-declaration-list:
873///         struct-declaration
874///         struct-declaration-list struct-declaration
875/// [OBC]   '@' 'defs' '(' class-name ')'
876///
877void Parser::ParseStructUnionBody(SourceLocation RecordLoc,
878                                  unsigned TagType, DeclTy *TagDecl) {
879  SourceLocation LBraceLoc = ConsumeBrace();
880
881  // Empty structs are an extension in C (C99 6.7.2.1p7), but are allowed in
882  // C++.
883  if (Tok.is(tok::r_brace) && !getLang().CPlusPlus)
884    Diag(Tok, diag::ext_empty_struct_union_enum)
885      << DeclSpec::getSpecifierName((DeclSpec::TST)TagType);
886
887  llvm::SmallVector<DeclTy*, 32> FieldDecls;
888  llvm::SmallVector<FieldDeclarator, 8> FieldDeclarators;
889
890  // While we still have something to read, read the declarations in the struct.
891  while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof)) {
892    // Each iteration of this loop reads one struct-declaration.
893
894    // Check for extraneous top-level semicolon.
895    if (Tok.is(tok::semi)) {
896      Diag(Tok, diag::ext_extra_struct_semi);
897      ConsumeToken();
898      continue;
899    }
900
901    // Parse all the comma separated declarators.
902    DeclSpec DS;
903    FieldDeclarators.clear();
904    if (!Tok.is(tok::at)) {
905      ParseStructDeclaration(DS, FieldDeclarators);
906
907      // Convert them all to fields.
908      for (unsigned i = 0, e = FieldDeclarators.size(); i != e; ++i) {
909        FieldDeclarator &FD = FieldDeclarators[i];
910        // Install the declarator into the current TagDecl.
911        DeclTy *Field = Actions.ActOnField(CurScope,
912                                           DS.getSourceRange().getBegin(),
913                                           FD.D, FD.BitfieldSize);
914        FieldDecls.push_back(Field);
915      }
916    } else { // Handle @defs
917      ConsumeToken();
918      if (!Tok.isObjCAtKeyword(tok::objc_defs)) {
919        Diag(Tok, diag::err_unexpected_at);
920        SkipUntil(tok::semi, true, true);
921        continue;
922      }
923      ConsumeToken();
924      ExpectAndConsume(tok::l_paren, diag::err_expected_lparen);
925      if (!Tok.is(tok::identifier)) {
926        Diag(Tok, diag::err_expected_ident);
927        SkipUntil(tok::semi, true, true);
928        continue;
929      }
930      llvm::SmallVector<DeclTy*, 16> Fields;
931      Actions.ActOnDefs(CurScope, Tok.getLocation(), Tok.getIdentifierInfo(),
932          Fields);
933      FieldDecls.insert(FieldDecls.end(), Fields.begin(), Fields.end());
934      ConsumeToken();
935      ExpectAndConsume(tok::r_paren, diag::err_expected_rparen);
936    }
937
938    if (Tok.is(tok::semi)) {
939      ConsumeToken();
940    } else if (Tok.is(tok::r_brace)) {
941      Diag(Tok, diag::ext_expected_semi_decl_list);
942      break;
943    } else {
944      Diag(Tok, diag::err_expected_semi_decl_list);
945      // Skip to end of block or statement
946      SkipUntil(tok::r_brace, true, true);
947    }
948  }
949
950  SourceLocation RBraceLoc = MatchRHSPunctuation(tok::r_brace, LBraceLoc);
951
952  AttributeList *AttrList = 0;
953  // If attributes exist after struct contents, parse them.
954  if (Tok.is(tok::kw___attribute))
955    AttrList = ParseAttributes();
956
957  Actions.ActOnFields(CurScope,
958                      RecordLoc,TagDecl,&FieldDecls[0],FieldDecls.size(),
959                      LBraceLoc, RBraceLoc,
960                      AttrList);
961}
962
963
964/// ParseEnumSpecifier
965///       enum-specifier: [C99 6.7.2.2]
966///         'enum' identifier[opt] '{' enumerator-list '}'
967///[C99/C++]'enum' identifier[opt] '{' enumerator-list ',' '}'
968/// [GNU]   'enum' attributes[opt] identifier[opt] '{' enumerator-list ',' [opt]
969///                                                 '}' attributes[opt]
970///         'enum' identifier
971/// [GNU]   'enum' attributes[opt] identifier
972///
973/// [C++] elaborated-type-specifier:
974/// [C++]   'enum' '::'[opt] nested-name-specifier[opt] identifier
975///
976void Parser::ParseEnumSpecifier(DeclSpec &DS) {
977  assert(Tok.is(tok::kw_enum) && "Not an enum specifier");
978  SourceLocation StartLoc = ConsumeToken();
979
980  // Parse the tag portion of this.
981
982  AttributeList *Attr = 0;
983  // If attributes exist after tag, parse them.
984  if (Tok.is(tok::kw___attribute))
985    Attr = ParseAttributes();
986
987  CXXScopeSpec SS;
988  if (getLang().CPlusPlus && MaybeParseCXXScopeSpecifier(SS)) {
989    if (Tok.isNot(tok::identifier)) {
990      Diag(Tok, diag::err_expected_ident);
991      if (Tok.isNot(tok::l_brace)) {
992        // Has no name and is not a definition.
993        // Skip the rest of this declarator, up until the comma or semicolon.
994        SkipUntil(tok::comma, true);
995        return;
996      }
997    }
998  }
999
1000  // Must have either 'enum name' or 'enum {...}'.
1001  if (Tok.isNot(tok::identifier) && Tok.isNot(tok::l_brace)) {
1002    Diag(Tok, diag::err_expected_ident_lbrace);
1003
1004    // Skip the rest of this declarator, up until the comma or semicolon.
1005    SkipUntil(tok::comma, true);
1006    return;
1007  }
1008
1009  // If an identifier is present, consume and remember it.
1010  IdentifierInfo *Name = 0;
1011  SourceLocation NameLoc;
1012  if (Tok.is(tok::identifier)) {
1013    Name = Tok.getIdentifierInfo();
1014    NameLoc = ConsumeToken();
1015  }
1016
1017  // There are three options here.  If we have 'enum foo;', then this is a
1018  // forward declaration.  If we have 'enum foo {...' then this is a
1019  // definition. Otherwise we have something like 'enum foo xyz', a reference.
1020  //
1021  // This is needed to handle stuff like this right (C99 6.7.2.3p11):
1022  // enum foo {..};  void bar() { enum foo; }    <- new foo in bar.
1023  // enum foo {..};  void bar() { enum foo x; }  <- use of old foo.
1024  //
1025  Action::TagKind TK;
1026  if (Tok.is(tok::l_brace))
1027    TK = Action::TK_Definition;
1028  else if (Tok.is(tok::semi))
1029    TK = Action::TK_Declaration;
1030  else
1031    TK = Action::TK_Reference;
1032  DeclTy *TagDecl = Actions.ActOnTag(CurScope, DeclSpec::TST_enum, TK, StartLoc,
1033                                     SS, Name, NameLoc, Attr);
1034
1035  if (Tok.is(tok::l_brace))
1036    ParseEnumBody(StartLoc, TagDecl);
1037
1038  // TODO: semantic analysis on the declspec for enums.
1039  const char *PrevSpec = 0;
1040  if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc, PrevSpec, TagDecl))
1041    Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
1042}
1043
1044/// ParseEnumBody - Parse a {} enclosed enumerator-list.
1045///       enumerator-list:
1046///         enumerator
1047///         enumerator-list ',' enumerator
1048///       enumerator:
1049///         enumeration-constant
1050///         enumeration-constant '=' constant-expression
1051///       enumeration-constant:
1052///         identifier
1053///
1054void Parser::ParseEnumBody(SourceLocation StartLoc, DeclTy *EnumDecl) {
1055  SourceLocation LBraceLoc = ConsumeBrace();
1056
1057  // C does not allow an empty enumerator-list, C++ does [dcl.enum].
1058  if (Tok.is(tok::r_brace) && !getLang().CPlusPlus)
1059    Diag(Tok, diag::ext_empty_struct_union_enum) << "enum";
1060
1061  llvm::SmallVector<DeclTy*, 32> EnumConstantDecls;
1062
1063  DeclTy *LastEnumConstDecl = 0;
1064
1065  // Parse the enumerator-list.
1066  while (Tok.is(tok::identifier)) {
1067    IdentifierInfo *Ident = Tok.getIdentifierInfo();
1068    SourceLocation IdentLoc = ConsumeToken();
1069
1070    SourceLocation EqualLoc;
1071    ExprTy *AssignedVal = 0;
1072    if (Tok.is(tok::equal)) {
1073      EqualLoc = ConsumeToken();
1074      ExprResult Res = ParseConstantExpression();
1075      if (Res.isInvalid)
1076        SkipUntil(tok::comma, tok::r_brace, true, true);
1077      else
1078        AssignedVal = Res.Val;
1079    }
1080
1081    // Install the enumerator constant into EnumDecl.
1082    DeclTy *EnumConstDecl = Actions.ActOnEnumConstant(CurScope, EnumDecl,
1083                                                      LastEnumConstDecl,
1084                                                      IdentLoc, Ident,
1085                                                      EqualLoc, AssignedVal);
1086    EnumConstantDecls.push_back(EnumConstDecl);
1087    LastEnumConstDecl = EnumConstDecl;
1088
1089    if (Tok.isNot(tok::comma))
1090      break;
1091    SourceLocation CommaLoc = ConsumeToken();
1092
1093    if (Tok.isNot(tok::identifier) && !getLang().C99)
1094      Diag(CommaLoc, diag::ext_c99_enumerator_list_comma);
1095  }
1096
1097  // Eat the }.
1098  MatchRHSPunctuation(tok::r_brace, LBraceLoc);
1099
1100  Actions.ActOnEnumBody(StartLoc, EnumDecl, &EnumConstantDecls[0],
1101                        EnumConstantDecls.size());
1102
1103  DeclTy *AttrList = 0;
1104  // If attributes exist after the identifier list, parse them.
1105  if (Tok.is(tok::kw___attribute))
1106    AttrList = ParseAttributes(); // FIXME: where do they do?
1107}
1108
1109/// isTypeSpecifierQualifier - Return true if the current token could be the
1110/// start of a type-qualifier-list.
1111bool Parser::isTypeQualifier() const {
1112  switch (Tok.getKind()) {
1113  default: return false;
1114    // type-qualifier
1115  case tok::kw_const:
1116  case tok::kw_volatile:
1117  case tok::kw_restrict:
1118    return true;
1119  }
1120}
1121
1122/// isTypeSpecifierQualifier - Return true if the current token could be the
1123/// start of a specifier-qualifier-list.
1124bool Parser::isTypeSpecifierQualifier() {
1125  // Annotate typenames and C++ scope specifiers.
1126  TryAnnotateTypeOrScopeToken();
1127
1128  switch (Tok.getKind()) {
1129  default: return false;
1130    // GNU attributes support.
1131  case tok::kw___attribute:
1132    // GNU typeof support.
1133  case tok::kw_typeof:
1134
1135    // type-specifiers
1136  case tok::kw_short:
1137  case tok::kw_long:
1138  case tok::kw_signed:
1139  case tok::kw_unsigned:
1140  case tok::kw__Complex:
1141  case tok::kw__Imaginary:
1142  case tok::kw_void:
1143  case tok::kw_char:
1144  case tok::kw_wchar_t:
1145  case tok::kw_int:
1146  case tok::kw_float:
1147  case tok::kw_double:
1148  case tok::kw_bool:
1149  case tok::kw__Bool:
1150  case tok::kw__Decimal32:
1151  case tok::kw__Decimal64:
1152  case tok::kw__Decimal128:
1153
1154    // struct-or-union-specifier (C99) or class-specifier (C++)
1155  case tok::kw_class:
1156  case tok::kw_struct:
1157  case tok::kw_union:
1158    // enum-specifier
1159  case tok::kw_enum:
1160
1161    // type-qualifier
1162  case tok::kw_const:
1163  case tok::kw_volatile:
1164  case tok::kw_restrict:
1165
1166    // typedef-name
1167  case tok::annot_qualtypename:
1168    return true;
1169
1170    // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
1171  case tok::less:
1172    return getLang().ObjC1;
1173  }
1174}
1175
1176/// isDeclarationSpecifier() - Return true if the current token is part of a
1177/// declaration specifier.
1178bool Parser::isDeclarationSpecifier() {
1179  // Annotate typenames and C++ scope specifiers.
1180  TryAnnotateTypeOrScopeToken();
1181
1182  switch (Tok.getKind()) {
1183  default: return false;
1184    // storage-class-specifier
1185  case tok::kw_typedef:
1186  case tok::kw_extern:
1187  case tok::kw___private_extern__:
1188  case tok::kw_static:
1189  case tok::kw_auto:
1190  case tok::kw_register:
1191  case tok::kw___thread:
1192
1193    // type-specifiers
1194  case tok::kw_short:
1195  case tok::kw_long:
1196  case tok::kw_signed:
1197  case tok::kw_unsigned:
1198  case tok::kw__Complex:
1199  case tok::kw__Imaginary:
1200  case tok::kw_void:
1201  case tok::kw_char:
1202  case tok::kw_wchar_t:
1203  case tok::kw_int:
1204  case tok::kw_float:
1205  case tok::kw_double:
1206  case tok::kw_bool:
1207  case tok::kw__Bool:
1208  case tok::kw__Decimal32:
1209  case tok::kw__Decimal64:
1210  case tok::kw__Decimal128:
1211
1212    // struct-or-union-specifier (C99) or class-specifier (C++)
1213  case tok::kw_class:
1214  case tok::kw_struct:
1215  case tok::kw_union:
1216    // enum-specifier
1217  case tok::kw_enum:
1218
1219    // type-qualifier
1220  case tok::kw_const:
1221  case tok::kw_volatile:
1222  case tok::kw_restrict:
1223
1224    // function-specifier
1225  case tok::kw_inline:
1226  case tok::kw_virtual:
1227  case tok::kw_explicit:
1228
1229    // typedef-name
1230  case tok::annot_qualtypename:
1231
1232    // GNU typeof support.
1233  case tok::kw_typeof:
1234
1235    // GNU attributes.
1236  case tok::kw___attribute:
1237    return true;
1238
1239    // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
1240  case tok::less:
1241    return getLang().ObjC1;
1242  }
1243}
1244
1245
1246/// ParseTypeQualifierListOpt
1247///       type-qualifier-list: [C99 6.7.5]
1248///         type-qualifier
1249/// [GNU]   attributes
1250///         type-qualifier-list type-qualifier
1251/// [GNU]   type-qualifier-list attributes
1252///
1253void Parser::ParseTypeQualifierListOpt(DeclSpec &DS) {
1254  while (1) {
1255    int isInvalid = false;
1256    const char *PrevSpec = 0;
1257    SourceLocation Loc = Tok.getLocation();
1258
1259    switch (Tok.getKind()) {
1260    default:
1261      // If this is not a type-qualifier token, we're done reading type
1262      // qualifiers.  First verify that DeclSpec's are consistent.
1263      DS.Finish(Diags, PP.getSourceManager(), getLang());
1264      return;
1265    case tok::kw_const:
1266      isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec,
1267                                 getLang())*2;
1268      break;
1269    case tok::kw_volatile:
1270      isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec,
1271                                 getLang())*2;
1272      break;
1273    case tok::kw_restrict:
1274      isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec,
1275                                 getLang())*2;
1276      break;
1277    case tok::kw___attribute:
1278      DS.AddAttributes(ParseAttributes());
1279      continue; // do *not* consume the next token!
1280    }
1281
1282    // If the specifier combination wasn't legal, issue a diagnostic.
1283    if (isInvalid) {
1284      assert(PrevSpec && "Method did not return previous specifier!");
1285      // Pick between error or extwarn.
1286      unsigned DiagID = isInvalid == 1 ? diag::err_invalid_decl_spec_combination
1287                                      : diag::ext_duplicate_declspec;
1288      Diag(Tok, DiagID) << PrevSpec;
1289    }
1290    ConsumeToken();
1291  }
1292}
1293
1294
1295/// ParseDeclarator - Parse and verify a newly-initialized declarator.
1296///
1297void Parser::ParseDeclarator(Declarator &D) {
1298  /// This implements the 'declarator' production in the C grammar, then checks
1299  /// for well-formedness and issues diagnostics.
1300  ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
1301}
1302
1303/// ParseDeclaratorInternal - Parse a C or C++ declarator. The direct-declarator
1304/// is parsed by the function passed to it. Pass null, and the direct-declarator
1305/// isn't parsed at all, making this function effectively parse the C++
1306/// ptr-operator production.
1307///
1308///       declarator: [C99 6.7.5]
1309///         pointer[opt] direct-declarator
1310/// [C++]   '&' declarator [C++ 8p4, dcl.decl]
1311/// [GNU]   '&' restrict[opt] attributes[opt] declarator
1312///
1313///       pointer: [C99 6.7.5]
1314///         '*' type-qualifier-list[opt]
1315///         '*' type-qualifier-list[opt] pointer
1316///
1317///       ptr-operator:
1318///         '*' cv-qualifier-seq[opt]
1319///         '&'
1320/// [GNU]   '&' restrict[opt] attributes[opt]
1321///         '::'[opt] nested-name-specifier '*' cv-qualifier-seq[opt] [TODO]
1322void Parser::ParseDeclaratorInternal(Declarator &D,
1323                                     DirectDeclParseFunction DirectDeclParser) {
1324  tok::TokenKind Kind = Tok.getKind();
1325
1326  // Not a pointer, C++ reference, or block.
1327  if (Kind != tok::star && (Kind != tok::amp || !getLang().CPlusPlus) &&
1328      (Kind != tok::caret || !getLang().Blocks)) {
1329    if (DirectDeclParser)
1330      (this->*DirectDeclParser)(D);
1331    return;
1332  }
1333
1334  // Otherwise, '*' -> pointer, '^' -> block, '&' -> reference.
1335  SourceLocation Loc = ConsumeToken();  // Eat the * or &.
1336
1337  if (Kind == tok::star || (Kind == tok::caret && getLang().Blocks)) {
1338    // Is a pointer.
1339    DeclSpec DS;
1340
1341    ParseTypeQualifierListOpt(DS);
1342
1343    // Recursively parse the declarator.
1344    ParseDeclaratorInternal(D, DirectDeclParser);
1345    if (Kind == tok::star)
1346      // Remember that we parsed a pointer type, and remember the type-quals.
1347      D.AddTypeInfo(DeclaratorChunk::getPointer(DS.getTypeQualifiers(), Loc,
1348                                                DS.TakeAttributes()));
1349    else
1350      // Remember that we parsed a Block type, and remember the type-quals.
1351      D.AddTypeInfo(DeclaratorChunk::getBlockPointer(DS.getTypeQualifiers(),
1352                                                     Loc));
1353  } else {
1354    // Is a reference
1355    DeclSpec DS;
1356
1357    // C++ 8.3.2p1: cv-qualified references are ill-formed except when the
1358    // cv-qualifiers are introduced through the use of a typedef or of a
1359    // template type argument, in which case the cv-qualifiers are ignored.
1360    //
1361    // [GNU] Retricted references are allowed.
1362    // [GNU] Attributes on references are allowed.
1363    ParseTypeQualifierListOpt(DS);
1364
1365    if (DS.getTypeQualifiers() != DeclSpec::TQ_unspecified) {
1366      if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
1367        Diag(DS.getConstSpecLoc(),
1368             diag::err_invalid_reference_qualifier_application) << "const";
1369      if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
1370        Diag(DS.getVolatileSpecLoc(),
1371             diag::err_invalid_reference_qualifier_application) << "volatile";
1372    }
1373
1374    // Recursively parse the declarator.
1375    ParseDeclaratorInternal(D, DirectDeclParser);
1376
1377    if (D.getNumTypeObjects() > 0) {
1378      // C++ [dcl.ref]p4: There shall be no references to references.
1379      DeclaratorChunk& InnerChunk = D.getTypeObject(D.getNumTypeObjects() - 1);
1380      if (InnerChunk.Kind == DeclaratorChunk::Reference) {
1381        if (const IdentifierInfo *II = D.getIdentifier())
1382          Diag(InnerChunk.Loc, diag::err_illegal_decl_reference_to_reference)
1383           << II;
1384        else
1385          Diag(InnerChunk.Loc, diag::err_illegal_decl_reference_to_reference)
1386            << "type name";
1387
1388        // Once we've complained about the reference-to-reference, we
1389        // can go ahead and build the (technically ill-formed)
1390        // declarator: reference collapsing will take care of it.
1391      }
1392    }
1393
1394    // Remember that we parsed a reference type. It doesn't have type-quals.
1395    D.AddTypeInfo(DeclaratorChunk::getReference(DS.getTypeQualifiers(), Loc,
1396                                                DS.TakeAttributes()));
1397  }
1398}
1399
1400/// ParseDirectDeclarator
1401///       direct-declarator: [C99 6.7.5]
1402/// [C99]   identifier
1403///         '(' declarator ')'
1404/// [GNU]   '(' attributes declarator ')'
1405/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1406/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1407/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1408/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1409/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1410///         direct-declarator '(' parameter-type-list ')'
1411///         direct-declarator '(' identifier-list[opt] ')'
1412/// [GNU]   direct-declarator '(' parameter-forward-declarations
1413///                    parameter-type-list[opt] ')'
1414/// [C++]   direct-declarator '(' parameter-declaration-clause ')'
1415///                    cv-qualifier-seq[opt] exception-specification[opt]
1416/// [C++]   declarator-id
1417///
1418///       declarator-id: [C++ 8]
1419///         id-expression
1420///         '::'[opt] nested-name-specifier[opt] type-name
1421///
1422///       id-expression: [C++ 5.1]
1423///         unqualified-id
1424///         qualified-id            [TODO]
1425///
1426///       unqualified-id: [C++ 5.1]
1427///         identifier
1428///         operator-function-id
1429///         conversion-function-id  [TODO]
1430///          '~' class-name
1431///         template-id             [TODO]
1432///
1433void Parser::ParseDirectDeclarator(Declarator &D) {
1434  CXXScopeSpec &SS = D.getCXXScopeSpec();
1435  DeclaratorScopeObj DeclScopeObj(*this, SS);
1436
1437  if (D.mayHaveIdentifier() &&
1438      getLang().CPlusPlus && MaybeParseCXXScopeSpecifier(SS)) {
1439    // Change the declaration context for name lookup, until this function is
1440    // exited (and the declarator has been parsed).
1441    DeclScopeObj.EnterDeclaratorScope();
1442  }
1443
1444  // Parse the first direct-declarator seen.
1445  if (Tok.is(tok::identifier) && D.mayHaveIdentifier()) {
1446    assert(Tok.getIdentifierInfo() && "Not an identifier?");
1447    // Determine whether this identifier is a C++ constructor name or
1448    // a normal identifier.
1449    if (getLang().CPlusPlus &&
1450        Actions.isCurrentClassName(*Tok.getIdentifierInfo(), CurScope))
1451      D.setConstructor(Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope),
1452                       Tok.getLocation());
1453    else
1454      D.SetIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1455    ConsumeToken();
1456  } else if (getLang().CPlusPlus &&
1457             Tok.is(tok::tilde) && D.mayHaveIdentifier()) {
1458    // This should be a C++ destructor.
1459    SourceLocation TildeLoc = ConsumeToken();
1460    if (Tok.is(tok::identifier)) {
1461      if (TypeTy *Type = ParseClassName())
1462        D.setDestructor(Type, TildeLoc);
1463      else
1464        D.SetIdentifier(0, TildeLoc);
1465    } else {
1466      Diag(Tok, diag::err_expected_class_name);
1467      D.SetIdentifier(0, TildeLoc);
1468    }
1469  } else if (Tok.is(tok::kw_operator)) {
1470    SourceLocation OperatorLoc = Tok.getLocation();
1471
1472    // First try the name of an overloaded operator
1473    if (OverloadedOperatorKind Op = TryParseOperatorFunctionId()) {
1474      D.setOverloadedOperator(Op, OperatorLoc);
1475    } else {
1476      // This must be a conversion function (C++ [class.conv.fct]).
1477      if (TypeTy *ConvType = ParseConversionFunctionId()) {
1478        D.setConversionFunction(ConvType, OperatorLoc);
1479      }
1480    }
1481  } else if (Tok.is(tok::l_paren) && SS.isEmpty()) {
1482    // direct-declarator: '(' declarator ')'
1483    // direct-declarator: '(' attributes declarator ')'
1484    // Example: 'char (*X)'   or 'int (*XX)(void)'
1485    ParseParenDeclarator(D);
1486  } else if (D.mayOmitIdentifier() && SS.isEmpty()) {
1487    // This could be something simple like "int" (in which case the declarator
1488    // portion is empty), if an abstract-declarator is allowed.
1489    D.SetIdentifier(0, Tok.getLocation());
1490  } else {
1491    if (getLang().CPlusPlus)
1492      Diag(Tok, diag::err_expected_unqualified_id);
1493    else
1494      Diag(Tok, diag::err_expected_ident_lparen);
1495    D.SetIdentifier(0, Tok.getLocation());
1496    D.setInvalidType(true);
1497  }
1498
1499  assert(D.isPastIdentifier() &&
1500         "Haven't past the location of the identifier yet?");
1501
1502  while (1) {
1503    if (Tok.is(tok::l_paren)) {
1504      // The paren may be part of a C++ direct initializer, eg. "int x(1);".
1505      // In such a case, check if we actually have a function declarator; if it
1506      // is not, the declarator has been fully parsed.
1507      if (getLang().CPlusPlus && D.mayBeFollowedByCXXDirectInit()) {
1508        // When not in file scope, warn for ambiguous function declarators, just
1509        // in case the author intended it as a variable definition.
1510        bool warnIfAmbiguous = D.getContext() != Declarator::FileContext;
1511        if (!isCXXFunctionDeclarator(warnIfAmbiguous))
1512          break;
1513      }
1514      ParseFunctionDeclarator(ConsumeParen(), D);
1515    } else if (Tok.is(tok::l_square)) {
1516      ParseBracketDeclarator(D);
1517    } else {
1518      break;
1519    }
1520  }
1521}
1522
1523/// ParseParenDeclarator - We parsed the declarator D up to a paren.  This is
1524/// only called before the identifier, so these are most likely just grouping
1525/// parens for precedence.  If we find that these are actually function
1526/// parameter parens in an abstract-declarator, we call ParseFunctionDeclarator.
1527///
1528///       direct-declarator:
1529///         '(' declarator ')'
1530/// [GNU]   '(' attributes declarator ')'
1531///         direct-declarator '(' parameter-type-list ')'
1532///         direct-declarator '(' identifier-list[opt] ')'
1533/// [GNU]   direct-declarator '(' parameter-forward-declarations
1534///                    parameter-type-list[opt] ')'
1535///
1536void Parser::ParseParenDeclarator(Declarator &D) {
1537  SourceLocation StartLoc = ConsumeParen();
1538  assert(!D.isPastIdentifier() && "Should be called before passing identifier");
1539
1540  // Eat any attributes before we look at whether this is a grouping or function
1541  // declarator paren.  If this is a grouping paren, the attribute applies to
1542  // the type being built up, for example:
1543  //     int (__attribute__(()) *x)(long y)
1544  // If this ends up not being a grouping paren, the attribute applies to the
1545  // first argument, for example:
1546  //     int (__attribute__(()) int x)
1547  // In either case, we need to eat any attributes to be able to determine what
1548  // sort of paren this is.
1549  //
1550  AttributeList *AttrList = 0;
1551  bool RequiresArg = false;
1552  if (Tok.is(tok::kw___attribute)) {
1553    AttrList = ParseAttributes();
1554
1555    // We require that the argument list (if this is a non-grouping paren) be
1556    // present even if the attribute list was empty.
1557    RequiresArg = true;
1558  }
1559
1560  // If we haven't past the identifier yet (or where the identifier would be
1561  // stored, if this is an abstract declarator), then this is probably just
1562  // grouping parens. However, if this could be an abstract-declarator, then
1563  // this could also be the start of function arguments (consider 'void()').
1564  bool isGrouping;
1565
1566  if (!D.mayOmitIdentifier()) {
1567    // If this can't be an abstract-declarator, this *must* be a grouping
1568    // paren, because we haven't seen the identifier yet.
1569    isGrouping = true;
1570  } else if (Tok.is(tok::r_paren) ||           // 'int()' is a function.
1571             (getLang().CPlusPlus && Tok.is(tok::ellipsis)) || // C++ int(...)
1572             isDeclarationSpecifier()) {       // 'int(int)' is a function.
1573    // This handles C99 6.7.5.3p11: in "typedef int X; void foo(X)", X is
1574    // considered to be a type, not a K&R identifier-list.
1575    isGrouping = false;
1576  } else {
1577    // Otherwise, this is a grouping paren, e.g. 'int (*X)' or 'int(X)'.
1578    isGrouping = true;
1579  }
1580
1581  // If this is a grouping paren, handle:
1582  // direct-declarator: '(' declarator ')'
1583  // direct-declarator: '(' attributes declarator ')'
1584  if (isGrouping) {
1585    bool hadGroupingParens = D.hasGroupingParens();
1586    D.setGroupingParens(true);
1587    if (AttrList)
1588      D.AddAttributes(AttrList);
1589
1590    ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
1591    // Match the ')'.
1592    MatchRHSPunctuation(tok::r_paren, StartLoc);
1593
1594    D.setGroupingParens(hadGroupingParens);
1595    return;
1596  }
1597
1598  // Okay, if this wasn't a grouping paren, it must be the start of a function
1599  // argument list.  Recognize that this declarator will never have an
1600  // identifier (and remember where it would have been), then call into
1601  // ParseFunctionDeclarator to handle of argument list.
1602  D.SetIdentifier(0, Tok.getLocation());
1603
1604  ParseFunctionDeclarator(StartLoc, D, AttrList, RequiresArg);
1605}
1606
1607/// ParseFunctionDeclarator - We are after the identifier and have parsed the
1608/// declarator D up to a paren, which indicates that we are parsing function
1609/// arguments.
1610///
1611/// If AttrList is non-null, then the caller parsed those arguments immediately
1612/// after the open paren - they should be considered to be the first argument of
1613/// a parameter.  If RequiresArg is true, then the first argument of the
1614/// function is required to be present and required to not be an identifier
1615/// list.
1616///
1617/// This method also handles this portion of the grammar:
1618///       parameter-type-list: [C99 6.7.5]
1619///         parameter-list
1620///         parameter-list ',' '...'
1621///
1622///       parameter-list: [C99 6.7.5]
1623///         parameter-declaration
1624///         parameter-list ',' parameter-declaration
1625///
1626///       parameter-declaration: [C99 6.7.5]
1627///         declaration-specifiers declarator
1628/// [C++]   declaration-specifiers declarator '=' assignment-expression
1629/// [GNU]   declaration-specifiers declarator attributes
1630///         declaration-specifiers abstract-declarator[opt]
1631/// [C++]   declaration-specifiers abstract-declarator[opt]
1632///           '=' assignment-expression
1633/// [GNU]   declaration-specifiers abstract-declarator[opt] attributes
1634///
1635/// For C++, after the parameter-list, it also parses "cv-qualifier-seq[opt]"
1636/// and "exception-specification[opt]"(TODO).
1637///
1638void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D,
1639                                     AttributeList *AttrList,
1640                                     bool RequiresArg) {
1641  // lparen is already consumed!
1642  assert(D.isPastIdentifier() && "Should not call before identifier!");
1643
1644  // This parameter list may be empty.
1645  if (Tok.is(tok::r_paren)) {
1646    if (RequiresArg) {
1647      Diag(Tok, diag::err_argument_required_after_attribute);
1648      delete AttrList;
1649    }
1650
1651    ConsumeParen();  // Eat the closing ')'.
1652
1653    // cv-qualifier-seq[opt].
1654    DeclSpec DS;
1655    if (getLang().CPlusPlus) {
1656      ParseTypeQualifierListOpt(DS);
1657
1658      // Parse exception-specification[opt].
1659      if (Tok.is(tok::kw_throw))
1660        ParseExceptionSpecification();
1661    }
1662
1663    // Remember that we parsed a function type, and remember the attributes.
1664    // int() -> no prototype, no '...'.
1665    D.AddTypeInfo(DeclaratorChunk::getFunction(/*prototype*/getLang().CPlusPlus,
1666                                               /*variadic*/ false,
1667                                               /*arglist*/ 0, 0,
1668                                               DS.getTypeQualifiers(),
1669                                               LParenLoc));
1670    return;
1671  }
1672
1673  // Alternatively, this parameter list may be an identifier list form for a
1674  // K&R-style function:  void foo(a,b,c)
1675  if (!getLang().CPlusPlus && Tok.is(tok::identifier) &&
1676      // K&R identifier lists can't have typedefs as identifiers, per
1677      // C99 6.7.5.3p11.
1678      !Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope)) {
1679    if (RequiresArg) {
1680      Diag(Tok, diag::err_argument_required_after_attribute);
1681      delete AttrList;
1682    }
1683
1684    // Identifier list.  Note that '(' identifier-list ')' is only allowed for
1685    // normal declarators, not for abstract-declarators.
1686    return ParseFunctionDeclaratorIdentifierList(LParenLoc, D);
1687  }
1688
1689  // Finally, a normal, non-empty parameter type list.
1690
1691  // Build up an array of information about the parsed arguments.
1692  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1693
1694  // Enter function-declaration scope, limiting any declarators to the
1695  // function prototype scope, including parameter declarators.
1696  EnterScope(Scope::FnScope|Scope::DeclScope);
1697
1698  bool IsVariadic = false;
1699  while (1) {
1700    if (Tok.is(tok::ellipsis)) {
1701      IsVariadic = true;
1702
1703      // Check to see if this is "void(...)" which is not allowed.
1704      if (!getLang().CPlusPlus && ParamInfo.empty()) {
1705        // Otherwise, parse parameter type list.  If it starts with an
1706        // ellipsis,  diagnose the malformed function.
1707        Diag(Tok, diag::err_ellipsis_first_arg);
1708        IsVariadic = false;       // Treat this like 'void()'.
1709      }
1710
1711      ConsumeToken();     // Consume the ellipsis.
1712      break;
1713    }
1714
1715    SourceLocation DSStart = Tok.getLocation();
1716
1717    // Parse the declaration-specifiers.
1718    DeclSpec DS;
1719
1720    // If the caller parsed attributes for the first argument, add them now.
1721    if (AttrList) {
1722      DS.AddAttributes(AttrList);
1723      AttrList = 0;  // Only apply the attributes to the first parameter.
1724    }
1725    ParseDeclarationSpecifiers(DS);
1726
1727    // Parse the declarator.  This is "PrototypeContext", because we must
1728    // accept either 'declarator' or 'abstract-declarator' here.
1729    Declarator ParmDecl(DS, Declarator::PrototypeContext);
1730    ParseDeclarator(ParmDecl);
1731
1732    // Parse GNU attributes, if present.
1733    if (Tok.is(tok::kw___attribute))
1734      ParmDecl.AddAttributes(ParseAttributes());
1735
1736    // Remember this parsed parameter in ParamInfo.
1737    IdentifierInfo *ParmII = ParmDecl.getIdentifier();
1738
1739    // If no parameter was specified, verify that *something* was specified,
1740    // otherwise we have a missing type and identifier.
1741    if (DS.getParsedSpecifiers() == DeclSpec::PQ_None &&
1742        ParmDecl.getIdentifier() == 0 && ParmDecl.getNumTypeObjects() == 0) {
1743      // Completely missing, emit error.
1744      Diag(DSStart, diag::err_missing_param);
1745    } else {
1746      // Otherwise, we have something.  Add it and let semantic analysis try
1747      // to grok it and add the result to the ParamInfo we are building.
1748
1749      // Inform the actions module about the parameter declarator, so it gets
1750      // added to the current scope.
1751      DeclTy *Param = Actions.ActOnParamDeclarator(CurScope, ParmDecl);
1752
1753      // Parse the default argument, if any. We parse the default
1754      // arguments in all dialects; the semantic analysis in
1755      // ActOnParamDefaultArgument will reject the default argument in
1756      // C.
1757      if (Tok.is(tok::equal)) {
1758        SourceLocation EqualLoc = Tok.getLocation();
1759
1760        // Consume the '='.
1761        ConsumeToken();
1762
1763        // Parse the default argument
1764        ExprResult DefArgResult = ParseAssignmentExpression();
1765        if (DefArgResult.isInvalid) {
1766          SkipUntil(tok::comma, tok::r_paren, true, true);
1767        } else {
1768          // Inform the actions module about the default argument
1769          Actions.ActOnParamDefaultArgument(Param, EqualLoc, DefArgResult.Val);
1770        }
1771      }
1772
1773      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1774                             ParmDecl.getIdentifierLoc(), Param));
1775    }
1776
1777    // If the next token is a comma, consume it and keep reading arguments.
1778    if (Tok.isNot(tok::comma)) break;
1779
1780    // Consume the comma.
1781    ConsumeToken();
1782  }
1783
1784  // Leave prototype scope.
1785  ExitScope();
1786
1787  // If we have the closing ')', eat it.
1788  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1789
1790  DeclSpec DS;
1791  if (getLang().CPlusPlus) {
1792    // Parse cv-qualifier-seq[opt].
1793    ParseTypeQualifierListOpt(DS);
1794
1795    // Parse exception-specification[opt].
1796    if (Tok.is(tok::kw_throw))
1797      ParseExceptionSpecification();
1798  }
1799
1800  // Remember that we parsed a function type, and remember the attributes.
1801  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/true, IsVariadic,
1802                                             &ParamInfo[0], ParamInfo.size(),
1803                                             DS.getTypeQualifiers(),
1804                                             LParenLoc));
1805}
1806
1807/// ParseFunctionDeclaratorIdentifierList - While parsing a function declarator
1808/// we found a K&R-style identifier list instead of a type argument list.  The
1809/// current token is known to be the first identifier in the list.
1810///
1811///       identifier-list: [C99 6.7.5]
1812///         identifier
1813///         identifier-list ',' identifier
1814///
1815void Parser::ParseFunctionDeclaratorIdentifierList(SourceLocation LParenLoc,
1816                                                   Declarator &D) {
1817  // Build up an array of information about the parsed arguments.
1818  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1819  llvm::SmallSet<const IdentifierInfo*, 16> ParamsSoFar;
1820
1821  // If there was no identifier specified for the declarator, either we are in
1822  // an abstract-declarator, or we are in a parameter declarator which was found
1823  // to be abstract.  In abstract-declarators, identifier lists are not valid:
1824  // diagnose this.
1825  if (!D.getIdentifier())
1826    Diag(Tok, diag::ext_ident_list_in_param);
1827
1828  // Tok is known to be the first identifier in the list.  Remember this
1829  // identifier in ParamInfo.
1830  ParamsSoFar.insert(Tok.getIdentifierInfo());
1831  ParamInfo.push_back(DeclaratorChunk::ParamInfo(Tok.getIdentifierInfo(),
1832                                                 Tok.getLocation(), 0));
1833
1834  ConsumeToken();  // eat the first identifier.
1835
1836  while (Tok.is(tok::comma)) {
1837    // Eat the comma.
1838    ConsumeToken();
1839
1840    // If this isn't an identifier, report the error and skip until ')'.
1841    if (Tok.isNot(tok::identifier)) {
1842      Diag(Tok, diag::err_expected_ident);
1843      SkipUntil(tok::r_paren);
1844      return;
1845    }
1846
1847    IdentifierInfo *ParmII = Tok.getIdentifierInfo();
1848
1849    // Reject 'typedef int y; int test(x, y)', but continue parsing.
1850    if (Actions.isTypeName(*ParmII, CurScope))
1851      Diag(Tok, diag::err_unexpected_typedef_ident) << ParmII;
1852
1853    // Verify that the argument identifier has not already been mentioned.
1854    if (!ParamsSoFar.insert(ParmII)) {
1855      Diag(Tok, diag::err_param_redefinition) << ParmII;
1856    } else {
1857      // Remember this identifier in ParamInfo.
1858      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1859                                                     Tok.getLocation(), 0));
1860    }
1861
1862    // Eat the identifier.
1863    ConsumeToken();
1864  }
1865
1866  // Remember that we parsed a function type, and remember the attributes.  This
1867  // function type is always a K&R style function type, which is not varargs and
1868  // has no prototype.
1869  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/false, /*varargs*/false,
1870                                             &ParamInfo[0], ParamInfo.size(),
1871                                             /*TypeQuals*/0, LParenLoc));
1872
1873  // If we have the closing ')', eat it and we're done.
1874  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1875}
1876
1877/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1878/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1879/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1880/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1881/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1882void Parser::ParseBracketDeclarator(Declarator &D) {
1883  SourceLocation StartLoc = ConsumeBracket();
1884
1885  // If valid, this location is the position where we read the 'static' keyword.
1886  SourceLocation StaticLoc;
1887  if (Tok.is(tok::kw_static))
1888    StaticLoc = ConsumeToken();
1889
1890  // If there is a type-qualifier-list, read it now.
1891  DeclSpec DS;
1892  ParseTypeQualifierListOpt(DS);
1893
1894  // If we haven't already read 'static', check to see if there is one after the
1895  // type-qualifier-list.
1896  if (!StaticLoc.isValid() && Tok.is(tok::kw_static))
1897    StaticLoc = ConsumeToken();
1898
1899  // Handle "direct-declarator [ type-qual-list[opt] * ]".
1900  bool isStar = false;
1901  ExprResult NumElements(false);
1902
1903  // Handle the case where we have '[*]' as the array size.  However, a leading
1904  // star could be the start of an expression, for example 'X[*p + 4]'.  Verify
1905  // the the token after the star is a ']'.  Since stars in arrays are
1906  // infrequent, use of lookahead is not costly here.
1907  if (Tok.is(tok::star) && GetLookAheadToken(1).is(tok::r_square)) {
1908    ConsumeToken();  // Eat the '*'.
1909
1910    if (StaticLoc.isValid())
1911      Diag(StaticLoc, diag::err_unspecified_vla_size_with_static);
1912    StaticLoc = SourceLocation();  // Drop the static.
1913    isStar = true;
1914  } else if (Tok.isNot(tok::r_square)) {
1915    // Parse the assignment-expression now.
1916    NumElements = ParseAssignmentExpression();
1917  }
1918
1919  // If there was an error parsing the assignment-expression, recover.
1920  if (NumElements.isInvalid) {
1921    // If the expression was invalid, skip it.
1922    SkipUntil(tok::r_square);
1923    return;
1924  }
1925
1926  MatchRHSPunctuation(tok::r_square, StartLoc);
1927
1928  // If C99 isn't enabled, emit an ext-warn if the arg list wasn't empty and if
1929  // it was not a constant expression.
1930  if (!getLang().C99) {
1931    // TODO: check C90 array constant exprness.
1932    if (isStar || StaticLoc.isValid() ||
1933        0/*TODO: NumElts is not a C90 constantexpr */)
1934      Diag(StartLoc, diag::ext_c99_array_usage);
1935  }
1936
1937  // Remember that we parsed a pointer type, and remember the type-quals.
1938  D.AddTypeInfo(DeclaratorChunk::getArray(DS.getTypeQualifiers(),
1939                                          StaticLoc.isValid(), isStar,
1940                                          NumElements.Val, StartLoc));
1941}
1942
1943/// [GNU]   typeof-specifier:
1944///           typeof ( expressions )
1945///           typeof ( type-name )
1946/// [GNU/C++] typeof unary-expression
1947///
1948void Parser::ParseTypeofSpecifier(DeclSpec &DS) {
1949  assert(Tok.is(tok::kw_typeof) && "Not a typeof specifier");
1950  const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo();
1951  SourceLocation StartLoc = ConsumeToken();
1952
1953  if (Tok.isNot(tok::l_paren)) {
1954    if (!getLang().CPlusPlus) {
1955      Diag(Tok, diag::err_expected_lparen_after_id) << BuiltinII;
1956      return;
1957    }
1958
1959    ExprResult Result = ParseCastExpression(true/*isUnaryExpression*/);
1960    if (Result.isInvalid)
1961      return;
1962
1963    const char *PrevSpec = 0;
1964    // Check for duplicate type specifiers.
1965    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
1966                           Result.Val))
1967      Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
1968
1969    // FIXME: Not accurate, the range gets one token more than it should.
1970    DS.SetRangeEnd(Tok.getLocation());
1971    return;
1972  }
1973
1974  SourceLocation LParenLoc = ConsumeParen(), RParenLoc;
1975
1976  if (isTypeIdInParens()) {
1977    TypeTy *Ty = ParseTypeName();
1978
1979    assert(Ty && "Parser::ParseTypeofSpecifier(): missing type");
1980
1981    if (Tok.isNot(tok::r_paren)) {
1982      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1983      return;
1984    }
1985    RParenLoc = ConsumeParen();
1986    const char *PrevSpec = 0;
1987    // Check for duplicate type specifiers (e.g. "int typeof(int)").
1988    if (DS.SetTypeSpecType(DeclSpec::TST_typeofType, StartLoc, PrevSpec, Ty))
1989      Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
1990  } else { // we have an expression.
1991    ExprResult Result = ParseExpression();
1992    ExprGuard ResultGuard(Actions, Result);
1993
1994    if (Result.isInvalid || Tok.isNot(tok::r_paren)) {
1995      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1996      return;
1997    }
1998    RParenLoc = ConsumeParen();
1999    const char *PrevSpec = 0;
2000    // Check for duplicate type specifiers (e.g. "int typeof(int)").
2001    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
2002                           ResultGuard.take()))
2003      Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
2004  }
2005  DS.SetRangeEnd(RParenLoc);
2006}
2007
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2009