ParseDecl.cpp revision 1bfe1c2129771c06fb58ae5e8c079ae30e138309 
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/DeclSpec.h"
17#include "clang/Parse/Scope.h"
18#include "llvm/ADT/SmallSet.h"
19using namespace clang;
20
21//===----------------------------------------------------------------------===//
22// C99 6.7: Declarations.
23//===----------------------------------------------------------------------===//
24
25/// ParseTypeName
26///       type-name: [C99 6.7.6]
27///         specifier-qualifier-list abstract-declarator[opt]
28Parser::TypeTy *Parser::ParseTypeName() {
29  // Parse the common declaration-specifiers piece.
30  DeclSpec DS;
31  ParseSpecifierQualifierList(DS);
32
33  // Parse the abstract-declarator, if present.
34  Declarator DeclaratorInfo(DS, Declarator::TypeNameContext);
35  ParseDeclarator(DeclaratorInfo);
36
37  return Actions.ActOnTypeName(CurScope, DeclaratorInfo).Val;
38}
39
40/// ParseAttributes - Parse a non-empty attributes list.
41///
42/// [GNU] attributes:
43///         attribute
44///         attributes attribute
45///
46/// [GNU]  attribute:
47///          '__attribute__' '(' '(' attribute-list ')' ')'
48///
49/// [GNU]  attribute-list:
50///          attrib
51///          attribute_list ',' attrib
52///
53/// [GNU]  attrib:
54///          empty
55///          attrib-name
56///          attrib-name '(' identifier ')'
57///          attrib-name '(' identifier ',' nonempty-expr-list ')'
58///          attrib-name '(' argument-expression-list [C99 6.5.2] ')'
59///
60/// [GNU]  attrib-name:
61///          identifier
62///          typespec
63///          typequal
64///          storageclass
65///
66/// FIXME: The GCC grammar/code for this construct implies we need two
67/// token lookahead. Comment from gcc: "If they start with an identifier
68/// which is followed by a comma or close parenthesis, then the arguments
69/// start with that identifier; otherwise they are an expression list."
70///
71/// At the moment, I am not doing 2 token lookahead. I am also unaware of
72/// any attributes that don't work (based on my limited testing). Most
73/// attributes are very simple in practice. Until we find a bug, I don't see
74/// a pressing need to implement the 2 token lookahead.
75
76AttributeList *Parser::ParseAttributes() {
77  assert(Tok.is(tok::kw___attribute) && "Not an attribute list!");
78
79  AttributeList *CurrAttr = 0;
80
81  while (Tok.is(tok::kw___attribute)) {
82    ConsumeToken();
83    if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after,
84                         "attribute")) {
85      SkipUntil(tok::r_paren, true); // skip until ) or ;
86      return CurrAttr;
87    }
88    if (ExpectAndConsume(tok::l_paren, diag::err_expected_lparen_after, "(")) {
89      SkipUntil(tok::r_paren, true); // skip until ) or ;
90      return CurrAttr;
91    }
92    // Parse the attribute-list. e.g. __attribute__(( weak, alias("__f") ))
93    while (Tok.is(tok::identifier) || isDeclarationSpecifier() ||
94           Tok.is(tok::comma)) {
95
96      if (Tok.is(tok::comma)) {
97        // allows for empty/non-empty attributes. ((__vector_size__(16),,,,))
98        ConsumeToken();
99        continue;
100      }
101      // we have an identifier or declaration specifier (const, int, etc.)
102      IdentifierInfo *AttrName = Tok.getIdentifierInfo();
103      SourceLocation AttrNameLoc = ConsumeToken();
104
105      // check if we have a "paramterized" attribute
106      if (Tok.is(tok::l_paren)) {
107        ConsumeParen(); // ignore the left paren loc for now
108
109        if (Tok.is(tok::identifier)) {
110          IdentifierInfo *ParmName = Tok.getIdentifierInfo();
111          SourceLocation ParmLoc = ConsumeToken();
112
113          if (Tok.is(tok::r_paren)) {
114            // __attribute__(( mode(byte) ))
115            ConsumeParen(); // ignore the right paren loc for now
116            CurrAttr = new AttributeList(AttrName, AttrNameLoc,
117                                         ParmName, ParmLoc, 0, 0, CurrAttr);
118          } else if (Tok.is(tok::comma)) {
119            ConsumeToken();
120            // __attribute__(( format(printf, 1, 2) ))
121            llvm::SmallVector<ExprTy*, 8> ArgExprs;
122            bool ArgExprsOk = true;
123
124            // now parse the non-empty comma separated list of expressions
125            while (1) {
126              ExprResult ArgExpr = ParseAssignmentExpression();
127              if (ArgExpr.isInvalid) {
128                ArgExprsOk = false;
129                SkipUntil(tok::r_paren);
130                break;
131              } else {
132                ArgExprs.push_back(ArgExpr.Val);
133              }
134              if (Tok.isNot(tok::comma))
135                break;
136              ConsumeToken(); // Eat the comma, move to the next argument
137            }
138            if (ArgExprsOk && Tok.is(tok::r_paren)) {
139              ConsumeParen(); // ignore the right paren loc for now
140              CurrAttr = new AttributeList(AttrName, AttrNameLoc, ParmName,
141                           ParmLoc, &ArgExprs[0], ArgExprs.size(), CurrAttr);
142            }
143          }
144        } else { // not an identifier
145          // parse a possibly empty comma separated list of expressions
146          if (Tok.is(tok::r_paren)) {
147            // __attribute__(( nonnull() ))
148            ConsumeParen(); // ignore the right paren loc for now
149            CurrAttr = new AttributeList(AttrName, AttrNameLoc,
150                                         0, SourceLocation(), 0, 0, CurrAttr);
151          } else {
152            // __attribute__(( aligned(16) ))
153            llvm::SmallVector<ExprTy*, 8> ArgExprs;
154            bool ArgExprsOk = true;
155
156            // now parse the list of expressions
157            while (1) {
158              ExprResult ArgExpr = ParseAssignmentExpression();
159              if (ArgExpr.isInvalid) {
160                ArgExprsOk = false;
161                SkipUntil(tok::r_paren);
162                break;
163              } else {
164                ArgExprs.push_back(ArgExpr.Val);
165              }
166              if (Tok.isNot(tok::comma))
167                break;
168              ConsumeToken(); // Eat the comma, move to the next argument
169            }
170            // Match the ')'.
171            if (ArgExprsOk && Tok.is(tok::r_paren)) {
172              ConsumeParen(); // ignore the right paren loc for now
173              CurrAttr = new AttributeList(AttrName, AttrNameLoc, 0,
174                           SourceLocation(), &ArgExprs[0], ArgExprs.size(),
175                           CurrAttr);
176            }
177          }
178        }
179      } else {
180        CurrAttr = new AttributeList(AttrName, AttrNameLoc,
181                                     0, SourceLocation(), 0, 0, CurrAttr);
182      }
183    }
184    if (ExpectAndConsume(tok::r_paren, diag::err_expected_rparen))
185      SkipUntil(tok::r_paren, false);
186    if (ExpectAndConsume(tok::r_paren, diag::err_expected_rparen))
187      SkipUntil(tok::r_paren, false);
188  }
189  return CurrAttr;
190}
191
192/// ParseDeclaration - Parse a full 'declaration', which consists of
193/// declaration-specifiers, some number of declarators, and a semicolon.
194/// 'Context' should be a Declarator::TheContext value.
195///
196///       declaration: [C99 6.7]
197///         block-declaration ->
198///           simple-declaration
199///           others                   [FIXME]
200/// [C++]   namespace-definition
201///         others... [FIXME]
202///
203Parser::DeclTy *Parser::ParseDeclaration(unsigned Context) {
204  switch (Tok.getKind()) {
205  case tok::kw_namespace:
206    return ParseNamespace(Context);
207  default:
208    return ParseSimpleDeclaration(Context);
209  }
210}
211
212///       simple-declaration: [C99 6.7: declaration] [C++ 7p1: dcl.dcl]
213///         declaration-specifiers init-declarator-list[opt] ';'
214///[C90/C++]init-declarator-list ';'                             [TODO]
215/// [OMP]   threadprivate-directive                              [TODO]
216Parser::DeclTy *Parser::ParseSimpleDeclaration(unsigned Context) {
217  // Parse the common declaration-specifiers piece.
218  DeclSpec DS;
219  ParseDeclarationSpecifiers(DS);
220
221  // C99 6.7.2.3p6: Handle "struct-or-union identifier;", "enum { X };"
222  // declaration-specifiers init-declarator-list[opt] ';'
223  if (Tok.is(tok::semi)) {
224    ConsumeToken();
225    return Actions.ParsedFreeStandingDeclSpec(CurScope, DS);
226  }
227
228  Declarator DeclaratorInfo(DS, (Declarator::TheContext)Context);
229  ParseDeclarator(DeclaratorInfo);
230
231  return ParseInitDeclaratorListAfterFirstDeclarator(DeclaratorInfo);
232}
233
234
235/// ParseInitDeclaratorListAfterFirstDeclarator - Parse 'declaration' after
236/// parsing 'declaration-specifiers declarator'.  This method is split out this
237/// way to handle the ambiguity between top-level function-definitions and
238/// declarations.
239///
240///       init-declarator-list: [C99 6.7]
241///         init-declarator
242///         init-declarator-list ',' init-declarator
243///       init-declarator: [C99 6.7]
244///         declarator
245///         declarator '=' initializer
246/// [GNU]   declarator simple-asm-expr[opt] attributes[opt]
247/// [GNU]   declarator simple-asm-expr[opt] attributes[opt] '=' initializer
248///
249Parser::DeclTy *Parser::
250ParseInitDeclaratorListAfterFirstDeclarator(Declarator &D) {
251
252  // Declarators may be grouped together ("int X, *Y, Z();").  Provide info so
253  // that they can be chained properly if the actions want this.
254  Parser::DeclTy *LastDeclInGroup = 0;
255
256  // At this point, we know that it is not a function definition.  Parse the
257  // rest of the init-declarator-list.
258  while (1) {
259    // If a simple-asm-expr is present, parse it.
260    if (Tok.is(tok::kw_asm)) {
261      ExprResult AsmLabel = ParseSimpleAsm();
262      if (AsmLabel.isInvalid) {
263        SkipUntil(tok::semi);
264        return 0;
265      }
266
267      D.setAsmLabel(AsmLabel.Val);
268    }
269
270    // If attributes are present, parse them.
271    if (Tok.is(tok::kw___attribute))
272      D.AddAttributes(ParseAttributes());
273
274    // Inform the current actions module that we just parsed this declarator.
275    // FIXME: pass asm & attributes.
276    LastDeclInGroup = Actions.ActOnDeclarator(CurScope, D, LastDeclInGroup);
277
278    // Parse declarator '=' initializer.
279    if (Tok.is(tok::equal)) {
280      ConsumeToken();
281      ExprResult Init = ParseInitializer();
282      if (Init.isInvalid) {
283        SkipUntil(tok::semi);
284        return 0;
285      }
286      Actions.AddInitializerToDecl(LastDeclInGroup, Init.Val);
287    }
288
289    // If we don't have a comma, it is either the end of the list (a ';') or an
290    // error, bail out.
291    if (Tok.isNot(tok::comma))
292      break;
293
294    // Consume the comma.
295    ConsumeToken();
296
297    // Parse the next declarator.
298    D.clear();
299    ParseDeclarator(D);
300  }
301
302  if (Tok.is(tok::semi)) {
303    ConsumeToken();
304    return Actions.FinalizeDeclaratorGroup(CurScope, LastDeclInGroup);
305  }
306  // If this is an ObjC2 for-each loop, this is a successful declarator
307  // parse.  The syntax for these looks like:
308  // 'for' '(' declaration 'in' expr ')' statement
309  if (D.getContext()  == Declarator::ForContext && isTokIdentifier_in()) {
310    return Actions.FinalizeDeclaratorGroup(CurScope, LastDeclInGroup);
311  }
312  Diag(Tok, diag::err_parse_error);
313  // Skip to end of block or statement
314  SkipUntil(tok::r_brace, true, true);
315  if (Tok.is(tok::semi))
316    ConsumeToken();
317  return 0;
318}
319
320/// ParseSpecifierQualifierList
321///        specifier-qualifier-list:
322///          type-specifier specifier-qualifier-list[opt]
323///          type-qualifier specifier-qualifier-list[opt]
324/// [GNU]    attributes     specifier-qualifier-list[opt]
325///
326void Parser::ParseSpecifierQualifierList(DeclSpec &DS) {
327  /// specifier-qualifier-list is a subset of declaration-specifiers.  Just
328  /// parse declaration-specifiers and complain about extra stuff.
329  ParseDeclarationSpecifiers(DS);
330
331  // Validate declspec for type-name.
332  unsigned Specs = DS.getParsedSpecifiers();
333  if (Specs == DeclSpec::PQ_None && !DS.getNumProtocolQualifiers())
334    Diag(Tok, diag::err_typename_requires_specqual);
335
336  // Issue diagnostic and remove storage class if present.
337  if (Specs & DeclSpec::PQ_StorageClassSpecifier) {
338    if (DS.getStorageClassSpecLoc().isValid())
339      Diag(DS.getStorageClassSpecLoc(),diag::err_typename_invalid_storageclass);
340    else
341      Diag(DS.getThreadSpecLoc(), diag::err_typename_invalid_storageclass);
342    DS.ClearStorageClassSpecs();
343  }
344
345  // Issue diagnostic and remove function specfier if present.
346  if (Specs & DeclSpec::PQ_FunctionSpecifier) {
347    Diag(DS.getInlineSpecLoc(), diag::err_typename_invalid_functionspec);
348    DS.ClearFunctionSpecs();
349  }
350}
351
352/// ParseDeclarationSpecifiers
353///       declaration-specifiers: [C99 6.7]
354///         storage-class-specifier declaration-specifiers[opt]
355///         type-specifier declaration-specifiers[opt]
356///         type-qualifier declaration-specifiers[opt]
357/// [C99]   function-specifier declaration-specifiers[opt]
358/// [GNU]   attributes declaration-specifiers[opt]
359///
360///       storage-class-specifier: [C99 6.7.1]
361///         'typedef'
362///         'extern'
363///         'static'
364///         'auto'
365///         'register'
366/// [GNU]   '__thread'
367///       type-specifier: [C99 6.7.2]
368///         'void'
369///         'char'
370///         'short'
371///         'int'
372///         'long'
373///         'float'
374///         'double'
375///         'signed'
376///         'unsigned'
377///         struct-or-union-specifier
378///         enum-specifier
379///         typedef-name
380/// [C++]   'wchar_t'
381/// [C++]   'bool'
382/// [C99]   '_Bool'
383/// [C99]   '_Complex'
384/// [C99]   '_Imaginary'  // Removed in TC2?
385/// [GNU]   '_Decimal32'
386/// [GNU]   '_Decimal64'
387/// [GNU]   '_Decimal128'
388/// [GNU]   typeof-specifier
389/// [OBJC]  class-name objc-protocol-refs[opt]    [TODO]
390/// [OBJC]  typedef-name objc-protocol-refs[opt]  [TODO]
391///       type-qualifier:
392///         'const'
393///         'volatile'
394/// [C99]   'restrict'
395///       function-specifier: [C99 6.7.4]
396/// [C99]   'inline'
397///
398void Parser::ParseDeclarationSpecifiers(DeclSpec &DS) {
399  DS.SetRangeStart(Tok.getLocation());
400  while (1) {
401    int isInvalid = false;
402    const char *PrevSpec = 0;
403    SourceLocation Loc = Tok.getLocation();
404
405    switch (Tok.getKind()) {
406    default:
407    DoneWithDeclSpec:
408      // If this is not a declaration specifier token, we're done reading decl
409      // specifiers.  First verify that DeclSpec's are consistent.
410      DS.Finish(Diags, PP.getSourceManager(), getLang());
411      return;
412
413      // typedef-name
414    case tok::identifier: {
415      // This identifier can only be a typedef name if we haven't already seen
416      // a type-specifier.  Without this check we misparse:
417      //  typedef int X; struct Y { short X; };  as 'short int'.
418      if (DS.hasTypeSpecifier())
419        goto DoneWithDeclSpec;
420
421      // It has to be available as a typedef too!
422      TypeTy *TypeRep = Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope);
423      if (TypeRep == 0)
424        goto DoneWithDeclSpec;
425
426      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_typedef, Loc, PrevSpec,
427                                     TypeRep);
428      if (isInvalid)
429        break;
430
431      DS.SetRangeEnd(Tok.getLocation());
432      ConsumeToken(); // The identifier
433
434      // Objective-C supports syntax of the form 'id<proto1,proto2>' where 'id'
435      // is a specific typedef and 'itf<proto1,proto2>' where 'itf' is an
436      // Objective-C interface.  If we don't have Objective-C or a '<', this is
437      // just a normal reference to a typedef name.
438      if (!Tok.is(tok::less) || !getLang().ObjC1)
439        continue;
440
441      SourceLocation EndProtoLoc;
442      llvm::SmallVector<DeclTy *, 8> ProtocolDecl;
443      ParseObjCProtocolReferences(ProtocolDecl, false, EndProtoLoc);
444      DS.setProtocolQualifiers(&ProtocolDecl[0], ProtocolDecl.size());
445
446      DS.SetRangeEnd(EndProtoLoc);
447
448      // Need to support trailing type qualifiers (e.g. "id<p> const").
449      // If a type specifier follows, it will be diagnosed elsewhere.
450      continue;
451    }
452    // GNU attributes support.
453    case tok::kw___attribute:
454      DS.AddAttributes(ParseAttributes());
455      continue;
456
457    // storage-class-specifier
458    case tok::kw_typedef:
459      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_typedef, Loc, PrevSpec);
460      break;
461    case tok::kw_extern:
462      if (DS.isThreadSpecified())
463        Diag(Tok, diag::ext_thread_before, "extern");
464      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_extern, Loc, PrevSpec);
465      break;
466    case tok::kw___private_extern__:
467      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_private_extern, Loc,
468                                         PrevSpec);
469      break;
470    case tok::kw_static:
471      if (DS.isThreadSpecified())
472        Diag(Tok, diag::ext_thread_before, "static");
473      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_static, Loc, PrevSpec);
474      break;
475    case tok::kw_auto:
476      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_auto, Loc, PrevSpec);
477      break;
478    case tok::kw_register:
479      isInvalid = DS.SetStorageClassSpec(DeclSpec::SCS_register, Loc, PrevSpec);
480      break;
481    case tok::kw___thread:
482      isInvalid = DS.SetStorageClassSpecThread(Loc, PrevSpec)*2;
483      break;
484
485    // type-specifiers
486    case tok::kw_short:
487      isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_short, Loc, PrevSpec);
488      break;
489    case tok::kw_long:
490      if (DS.getTypeSpecWidth() != DeclSpec::TSW_long)
491        isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_long, Loc, PrevSpec);
492      else
493        isInvalid = DS.SetTypeSpecWidth(DeclSpec::TSW_longlong, Loc, PrevSpec);
494      break;
495    case tok::kw_signed:
496      isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_signed, Loc, PrevSpec);
497      break;
498    case tok::kw_unsigned:
499      isInvalid = DS.SetTypeSpecSign(DeclSpec::TSS_unsigned, Loc, PrevSpec);
500      break;
501    case tok::kw__Complex:
502      isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_complex, Loc, PrevSpec);
503      break;
504    case tok::kw__Imaginary:
505      isInvalid = DS.SetTypeSpecComplex(DeclSpec::TSC_imaginary, Loc, PrevSpec);
506      break;
507    case tok::kw_void:
508      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_void, Loc, PrevSpec);
509      break;
510    case tok::kw_char:
511      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_char, Loc, PrevSpec);
512      break;
513    case tok::kw_int:
514      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, PrevSpec);
515      break;
516    case tok::kw_float:
517      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_float, Loc, PrevSpec);
518      break;
519    case tok::kw_double:
520      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_double, Loc, PrevSpec);
521      break;
522    case tok::kw_wchar_t:       // [C++ 2.11p1]
523      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_wchar, Loc, PrevSpec);
524      break;
525    case tok::kw_bool:          // [C++ 2.11p1]
526    case tok::kw__Bool:
527      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_bool, Loc, PrevSpec);
528      break;
529    case tok::kw__Decimal32:
530      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal32, Loc, PrevSpec);
531      break;
532    case tok::kw__Decimal64:
533      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal64, Loc, PrevSpec);
534      break;
535    case tok::kw__Decimal128:
536      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_decimal128, Loc, PrevSpec);
537      break;
538
539    case tok::kw_class:
540    case tok::kw_struct:
541    case tok::kw_union:
542      ParseClassSpecifier(DS);
543      continue;
544    case tok::kw_enum:
545      ParseEnumSpecifier(DS);
546      continue;
547
548    // GNU typeof support.
549    case tok::kw_typeof:
550      ParseTypeofSpecifier(DS);
551      continue;
552
553    // type-qualifier
554    case tok::kw_const:
555      isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec,
556                                 getLang())*2;
557      break;
558    case tok::kw_volatile:
559      isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec,
560                                 getLang())*2;
561      break;
562    case tok::kw_restrict:
563      isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec,
564                                 getLang())*2;
565      break;
566
567    // function-specifier
568    case tok::kw_inline:
569      isInvalid = DS.SetFunctionSpecInline(Loc, PrevSpec);
570      break;
571
572    case tok::less:
573      // GCC ObjC supports types like "<SomeProtocol>" as a synonym for
574      // "id<SomeProtocol>".  This is hopelessly old fashioned and dangerous,
575      // but we support it.
576      if (DS.hasTypeSpecifier() || !getLang().ObjC1)
577        goto DoneWithDeclSpec;
578
579      {
580        SourceLocation EndProtoLoc;
581        llvm::SmallVector<DeclTy *, 8> ProtocolDecl;
582        ParseObjCProtocolReferences(ProtocolDecl, false, EndProtoLoc);
583        DS.setProtocolQualifiers(&ProtocolDecl[0], ProtocolDecl.size());
584        DS.SetRangeEnd(EndProtoLoc);
585
586        Diag(Loc, diag::warn_objc_protocol_qualifier_missing_id,
587             SourceRange(Loc, EndProtoLoc));
588        // Need to support trailing type qualifiers (e.g. "id<p> const").
589        // If a type specifier follows, it will be diagnosed elsewhere.
590        continue;
591      }
592    }
593    // If the specifier combination wasn't legal, issue a diagnostic.
594    if (isInvalid) {
595      assert(PrevSpec && "Method did not return previous specifier!");
596      if (isInvalid == 1)  // Error.
597        Diag(Tok, diag::err_invalid_decl_spec_combination, PrevSpec);
598      else                 // extwarn.
599        Diag(Tok, diag::ext_duplicate_declspec, PrevSpec);
600    }
601    DS.SetRangeEnd(Tok.getLocation());
602    ConsumeToken();
603  }
604}
605
606/// ParseStructDeclaration - Parse a struct declaration without the terminating
607/// semicolon.
608///
609///       struct-declaration:
610///         specifier-qualifier-list struct-declarator-list
611/// [GNU]   __extension__ struct-declaration
612/// [GNU]   specifier-qualifier-list
613///       struct-declarator-list:
614///         struct-declarator
615///         struct-declarator-list ',' struct-declarator
616/// [GNU]   struct-declarator-list ',' attributes[opt] struct-declarator
617///       struct-declarator:
618///         declarator
619/// [GNU]   declarator attributes[opt]
620///         declarator[opt] ':' constant-expression
621/// [GNU]   declarator[opt] ':' constant-expression attributes[opt]
622///
623void Parser::
624ParseStructDeclaration(DeclSpec &DS,
625                       llvm::SmallVectorImpl<FieldDeclarator> &Fields) {
626  // FIXME: When __extension__ is specified, disable extension diagnostics.
627  while (Tok.is(tok::kw___extension__))
628    ConsumeToken();
629
630  // Parse the common specifier-qualifiers-list piece.
631  SourceLocation DSStart = Tok.getLocation();
632  ParseSpecifierQualifierList(DS);
633  // TODO: Does specifier-qualifier list correctly check that *something* is
634  // specified?
635
636  // If there are no declarators, issue a warning.
637  if (Tok.is(tok::semi)) {
638    Diag(DSStart, diag::w_no_declarators);
639    return;
640  }
641
642  // Read struct-declarators until we find the semicolon.
643  Fields.push_back(FieldDeclarator(DS));
644  while (1) {
645    FieldDeclarator &DeclaratorInfo = Fields.back();
646
647    /// struct-declarator: declarator
648    /// struct-declarator: declarator[opt] ':' constant-expression
649    if (Tok.isNot(tok::colon))
650      ParseDeclarator(DeclaratorInfo.D);
651
652    if (Tok.is(tok::colon)) {
653      ConsumeToken();
654      ExprResult Res = ParseConstantExpression();
655      if (Res.isInvalid)
656        SkipUntil(tok::semi, true, true);
657      else
658        DeclaratorInfo.BitfieldSize = Res.Val;
659    }
660
661    // If attributes exist after the declarator, parse them.
662    if (Tok.is(tok::kw___attribute))
663      DeclaratorInfo.D.AddAttributes(ParseAttributes());
664
665    // If we don't have a comma, it is either the end of the list (a ';')
666    // or an error, bail out.
667    if (Tok.isNot(tok::comma))
668      return;
669
670    // Consume the comma.
671    ConsumeToken();
672
673    // Parse the next declarator.
674    Fields.push_back(FieldDeclarator(DS));
675
676    // Attributes are only allowed on the second declarator.
677    if (Tok.is(tok::kw___attribute))
678      Fields.back().D.AddAttributes(ParseAttributes());
679  }
680}
681
682/// ParseStructUnionBody
683///       struct-contents:
684///         struct-declaration-list
685/// [EXT]   empty
686/// [GNU]   "struct-declaration-list" without terminatoring ';'
687///       struct-declaration-list:
688///         struct-declaration
689///         struct-declaration-list struct-declaration
690/// [OBC]   '@' 'defs' '(' class-name ')'
691///
692void Parser::ParseStructUnionBody(SourceLocation RecordLoc,
693                                  unsigned TagType, DeclTy *TagDecl) {
694  SourceLocation LBraceLoc = ConsumeBrace();
695
696  // Empty structs are an extension in C (C99 6.7.2.1p7), but are allowed in
697  // C++.
698  if (Tok.is(tok::r_brace) && !getLang().CPlusPlus)
699    Diag(Tok, diag::ext_empty_struct_union_enum,
700         DeclSpec::getSpecifierName((DeclSpec::TST)TagType));
701
702  llvm::SmallVector<DeclTy*, 32> FieldDecls;
703  llvm::SmallVector<FieldDeclarator, 8> FieldDeclarators;
704
705  // While we still have something to read, read the declarations in the struct.
706  while (Tok.isNot(tok::r_brace) && Tok.isNot(tok::eof)) {
707    // Each iteration of this loop reads one struct-declaration.
708
709    // Check for extraneous top-level semicolon.
710    if (Tok.is(tok::semi)) {
711      Diag(Tok, diag::ext_extra_struct_semi);
712      ConsumeToken();
713      continue;
714    }
715
716    // Parse all the comma separated declarators.
717    DeclSpec DS;
718    FieldDeclarators.clear();
719    if (!Tok.is(tok::at)) {
720      ParseStructDeclaration(DS, FieldDeclarators);
721
722      // Convert them all to fields.
723      for (unsigned i = 0, e = FieldDeclarators.size(); i != e; ++i) {
724        FieldDeclarator &FD = FieldDeclarators[i];
725        // Install the declarator into the current TagDecl.
726        DeclTy *Field = Actions.ActOnField(CurScope,
727                                           DS.getSourceRange().getBegin(),
728                                           FD.D, FD.BitfieldSize);
729        FieldDecls.push_back(Field);
730      }
731    } else { // Handle @defs
732      ConsumeToken();
733      if (!Tok.isObjCAtKeyword(tok::objc_defs)) {
734        Diag(Tok, diag::err_unexpected_at);
735        SkipUntil(tok::semi, true, true);
736        continue;
737      }
738      ConsumeToken();
739      ExpectAndConsume(tok::l_paren, diag::err_expected_lparen);
740      if (!Tok.is(tok::identifier)) {
741        Diag(Tok, diag::err_expected_ident);
742        SkipUntil(tok::semi, true, true);
743        continue;
744      }
745      llvm::SmallVector<DeclTy*, 16> Fields;
746      Actions.ActOnDefs(CurScope, Tok.getLocation(), Tok.getIdentifierInfo(),
747          Fields);
748      FieldDecls.insert(FieldDecls.end(), Fields.begin(), Fields.end());
749      ConsumeToken();
750      ExpectAndConsume(tok::r_paren, diag::err_expected_rparen);
751    }
752
753    if (Tok.is(tok::semi)) {
754      ConsumeToken();
755    } else if (Tok.is(tok::r_brace)) {
756      Diag(Tok.getLocation(), diag::ext_expected_semi_decl_list);
757      break;
758    } else {
759      Diag(Tok, diag::err_expected_semi_decl_list);
760      // Skip to end of block or statement
761      SkipUntil(tok::r_brace, true, true);
762    }
763  }
764
765  SourceLocation RBraceLoc = MatchRHSPunctuation(tok::r_brace, LBraceLoc);
766
767  AttributeList *AttrList = 0;
768  // If attributes exist after struct contents, parse them.
769  if (Tok.is(tok::kw___attribute))
770    AttrList = ParseAttributes(); // FIXME: where should I put them?
771
772  Actions.ActOnFields(CurScope,
773                      RecordLoc,TagDecl,&FieldDecls[0],FieldDecls.size(),
774                      LBraceLoc, RBraceLoc,
775                      AttrList);
776}
777
778
779/// ParseEnumSpecifier
780///       enum-specifier: [C99 6.7.2.2]
781///         'enum' identifier[opt] '{' enumerator-list '}'
782/// [C99]   'enum' identifier[opt] '{' enumerator-list ',' '}'
783/// [GNU]   'enum' attributes[opt] identifier[opt] '{' enumerator-list ',' [opt]
784///                                                 '}' attributes[opt]
785///         'enum' identifier
786/// [GNU]   'enum' attributes[opt] identifier
787void Parser::ParseEnumSpecifier(DeclSpec &DS) {
788  assert(Tok.is(tok::kw_enum) && "Not an enum specifier");
789  SourceLocation StartLoc = ConsumeToken();
790
791  // Parse the tag portion of this.
792
793  AttributeList *Attr = 0;
794  // If attributes exist after tag, parse them.
795  if (Tok.is(tok::kw___attribute))
796    Attr = ParseAttributes();
797
798  // Must have either 'enum name' or 'enum {...}'.
799  if (Tok.isNot(tok::identifier) && Tok.isNot(tok::l_brace)) {
800    Diag(Tok, diag::err_expected_ident_lbrace);
801
802    // Skip the rest of this declarator, up until the comma or semicolon.
803    SkipUntil(tok::comma, true);
804    return;
805  }
806
807  // If an identifier is present, consume and remember it.
808  IdentifierInfo *Name = 0;
809  SourceLocation NameLoc;
810  if (Tok.is(tok::identifier)) {
811    Name = Tok.getIdentifierInfo();
812    NameLoc = ConsumeToken();
813  }
814
815  // There are three options here.  If we have 'enum foo;', then this is a
816  // forward declaration.  If we have 'enum foo {...' then this is a
817  // definition. Otherwise we have something like 'enum foo xyz', a reference.
818  //
819  // This is needed to handle stuff like this right (C99 6.7.2.3p11):
820  // enum foo {..};  void bar() { enum foo; }    <- new foo in bar.
821  // enum foo {..};  void bar() { enum foo x; }  <- use of old foo.
822  //
823  Action::TagKind TK;
824  if (Tok.is(tok::l_brace))
825    TK = Action::TK_Definition;
826  else if (Tok.is(tok::semi))
827    TK = Action::TK_Declaration;
828  else
829    TK = Action::TK_Reference;
830  DeclTy *TagDecl = Actions.ActOnTag(CurScope, DeclSpec::TST_enum, TK, StartLoc,
831                                     Name, NameLoc, Attr);
832
833  if (Tok.is(tok::l_brace))
834    ParseEnumBody(StartLoc, TagDecl);
835
836  // TODO: semantic analysis on the declspec for enums.
837  const char *PrevSpec = 0;
838  if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc, PrevSpec, TagDecl))
839    Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
840}
841
842/// ParseEnumBody - Parse a {} enclosed enumerator-list.
843///       enumerator-list:
844///         enumerator
845///         enumerator-list ',' enumerator
846///       enumerator:
847///         enumeration-constant
848///         enumeration-constant '=' constant-expression
849///       enumeration-constant:
850///         identifier
851///
852void Parser::ParseEnumBody(SourceLocation StartLoc, DeclTy *EnumDecl) {
853  SourceLocation LBraceLoc = ConsumeBrace();
854
855  // C does not allow an empty enumerator-list, C++ does [dcl.enum].
856  if (Tok.is(tok::r_brace) && !getLang().CPlusPlus)
857    Diag(Tok, diag::ext_empty_struct_union_enum, "enum");
858
859  llvm::SmallVector<DeclTy*, 32> EnumConstantDecls;
860
861  DeclTy *LastEnumConstDecl = 0;
862
863  // Parse the enumerator-list.
864  while (Tok.is(tok::identifier)) {
865    IdentifierInfo *Ident = Tok.getIdentifierInfo();
866    SourceLocation IdentLoc = ConsumeToken();
867
868    SourceLocation EqualLoc;
869    ExprTy *AssignedVal = 0;
870    if (Tok.is(tok::equal)) {
871      EqualLoc = ConsumeToken();
872      ExprResult Res = ParseConstantExpression();
873      if (Res.isInvalid)
874        SkipUntil(tok::comma, tok::r_brace, true, true);
875      else
876        AssignedVal = Res.Val;
877    }
878
879    // Install the enumerator constant into EnumDecl.
880    DeclTy *EnumConstDecl = Actions.ActOnEnumConstant(CurScope, EnumDecl,
881                                                      LastEnumConstDecl,
882                                                      IdentLoc, Ident,
883                                                      EqualLoc, AssignedVal);
884    EnumConstantDecls.push_back(EnumConstDecl);
885    LastEnumConstDecl = EnumConstDecl;
886
887    if (Tok.isNot(tok::comma))
888      break;
889    SourceLocation CommaLoc = ConsumeToken();
890
891    if (Tok.isNot(tok::identifier) && !getLang().C99)
892      Diag(CommaLoc, diag::ext_c99_enumerator_list_comma);
893  }
894
895  // Eat the }.
896  MatchRHSPunctuation(tok::r_brace, LBraceLoc);
897
898  Actions.ActOnEnumBody(StartLoc, EnumDecl, &EnumConstantDecls[0],
899                        EnumConstantDecls.size());
900
901  DeclTy *AttrList = 0;
902  // If attributes exist after the identifier list, parse them.
903  if (Tok.is(tok::kw___attribute))
904    AttrList = ParseAttributes(); // FIXME: where do they do?
905}
906
907/// isTypeSpecifierQualifier - Return true if the current token could be the
908/// start of a type-qualifier-list.
909bool Parser::isTypeQualifier() const {
910  switch (Tok.getKind()) {
911  default: return false;
912    // type-qualifier
913  case tok::kw_const:
914  case tok::kw_volatile:
915  case tok::kw_restrict:
916    return true;
917  }
918}
919
920/// isTypeSpecifierQualifier - Return true if the current token could be the
921/// start of a specifier-qualifier-list.
922bool Parser::isTypeSpecifierQualifier() const {
923  switch (Tok.getKind()) {
924  default: return false;
925    // GNU attributes support.
926  case tok::kw___attribute:
927    // GNU typeof support.
928  case tok::kw_typeof:
929    // GNU bizarre protocol extension. FIXME: make an extension?
930  case tok::less:
931
932    // type-specifiers
933  case tok::kw_short:
934  case tok::kw_long:
935  case tok::kw_signed:
936  case tok::kw_unsigned:
937  case tok::kw__Complex:
938  case tok::kw__Imaginary:
939  case tok::kw_void:
940  case tok::kw_char:
941  case tok::kw_wchar_t:
942  case tok::kw_int:
943  case tok::kw_float:
944  case tok::kw_double:
945  case tok::kw_bool:
946  case tok::kw__Bool:
947  case tok::kw__Decimal32:
948  case tok::kw__Decimal64:
949  case tok::kw__Decimal128:
950
951    // struct-or-union-specifier (C99) or class-specifier (C++)
952  case tok::kw_class:
953  case tok::kw_struct:
954  case tok::kw_union:
955    // enum-specifier
956  case tok::kw_enum:
957
958    // type-qualifier
959  case tok::kw_const:
960  case tok::kw_volatile:
961  case tok::kw_restrict:
962    return true;
963
964    // typedef-name
965  case tok::identifier:
966    return Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope) != 0;
967  }
968}
969
970/// isDeclarationSpecifier() - Return true if the current token is part of a
971/// declaration specifier.
972bool Parser::isDeclarationSpecifier() const {
973  switch (Tok.getKind()) {
974  default: return false;
975    // storage-class-specifier
976  case tok::kw_typedef:
977  case tok::kw_extern:
978  case tok::kw___private_extern__:
979  case tok::kw_static:
980  case tok::kw_auto:
981  case tok::kw_register:
982  case tok::kw___thread:
983
984    // type-specifiers
985  case tok::kw_short:
986  case tok::kw_long:
987  case tok::kw_signed:
988  case tok::kw_unsigned:
989  case tok::kw__Complex:
990  case tok::kw__Imaginary:
991  case tok::kw_void:
992  case tok::kw_char:
993  case tok::kw_wchar_t:
994  case tok::kw_int:
995  case tok::kw_float:
996  case tok::kw_double:
997  case tok::kw_bool:
998  case tok::kw__Bool:
999  case tok::kw__Decimal32:
1000  case tok::kw__Decimal64:
1001  case tok::kw__Decimal128:
1002
1003    // struct-or-union-specifier (C99) or class-specifier (C++)
1004  case tok::kw_class:
1005  case tok::kw_struct:
1006  case tok::kw_union:
1007    // enum-specifier
1008  case tok::kw_enum:
1009
1010    // type-qualifier
1011  case tok::kw_const:
1012  case tok::kw_volatile:
1013  case tok::kw_restrict:
1014
1015    // function-specifier
1016  case tok::kw_inline:
1017
1018    // GNU typeof support.
1019  case tok::kw_typeof:
1020
1021    // GNU attributes.
1022  case tok::kw___attribute:
1023    return true;
1024
1025    // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
1026  case tok::less:
1027    return getLang().ObjC1;
1028
1029    // typedef-name
1030  case tok::identifier:
1031    return Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope) != 0;
1032  }
1033}
1034
1035
1036/// ParseTypeQualifierListOpt
1037///       type-qualifier-list: [C99 6.7.5]
1038///         type-qualifier
1039/// [GNU]   attributes
1040///         type-qualifier-list type-qualifier
1041/// [GNU]   type-qualifier-list attributes
1042///
1043void Parser::ParseTypeQualifierListOpt(DeclSpec &DS) {
1044  while (1) {
1045    int isInvalid = false;
1046    const char *PrevSpec = 0;
1047    SourceLocation Loc = Tok.getLocation();
1048
1049    switch (Tok.getKind()) {
1050    default:
1051      // If this is not a type-qualifier token, we're done reading type
1052      // qualifiers.  First verify that DeclSpec's are consistent.
1053      DS.Finish(Diags, PP.getSourceManager(), getLang());
1054      return;
1055    case tok::kw_const:
1056      isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec,
1057                                 getLang())*2;
1058      break;
1059    case tok::kw_volatile:
1060      isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec,
1061                                 getLang())*2;
1062      break;
1063    case tok::kw_restrict:
1064      isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec,
1065                                 getLang())*2;
1066      break;
1067    case tok::kw___attribute:
1068      DS.AddAttributes(ParseAttributes());
1069      continue; // do *not* consume the next token!
1070    }
1071
1072    // If the specifier combination wasn't legal, issue a diagnostic.
1073    if (isInvalid) {
1074      assert(PrevSpec && "Method did not return previous specifier!");
1075      if (isInvalid == 1)  // Error.
1076        Diag(Tok, diag::err_invalid_decl_spec_combination, PrevSpec);
1077      else                 // extwarn.
1078        Diag(Tok, diag::ext_duplicate_declspec, PrevSpec);
1079    }
1080    ConsumeToken();
1081  }
1082}
1083
1084
1085/// ParseDeclarator - Parse and verify a newly-initialized declarator.
1086///
1087void Parser::ParseDeclarator(Declarator &D) {
1088  /// This implements the 'declarator' production in the C grammar, then checks
1089  /// for well-formedness and issues diagnostics.
1090  ParseDeclaratorInternal(D);
1091}
1092
1093/// ParseDeclaratorInternal
1094///       declarator: [C99 6.7.5]
1095///         pointer[opt] direct-declarator
1096/// [C++]   '&' declarator [C++ 8p4, dcl.decl]
1097/// [GNU]   '&' restrict[opt] attributes[opt] declarator
1098///
1099///       pointer: [C99 6.7.5]
1100///         '*' type-qualifier-list[opt]
1101///         '*' type-qualifier-list[opt] pointer
1102///
1103void Parser::ParseDeclaratorInternal(Declarator &D) {
1104  tok::TokenKind Kind = Tok.getKind();
1105
1106  // Not a pointer, C++ reference, or block.
1107  if (Kind != tok::star && (Kind != tok::amp || !getLang().CPlusPlus) &&
1108      (Kind != tok::caret || !getLang().Blocks))
1109    return ParseDirectDeclarator(D);
1110
1111  // Otherwise, '*' -> pointer, '^' -> block, '&' -> reference.
1112  SourceLocation Loc = ConsumeToken();  // Eat the * or &.
1113
1114  if (Kind == tok::star || (Kind == tok::caret && getLang().Blocks)) {
1115    // Is a pointer.
1116    DeclSpec DS;
1117
1118    ParseTypeQualifierListOpt(DS);
1119
1120    // Recursively parse the declarator.
1121    ParseDeclaratorInternal(D);
1122    if (Kind == tok::star)
1123      // Remember that we parsed a pointer type, and remember the type-quals.
1124      D.AddTypeInfo(DeclaratorChunk::getPointer(DS.getTypeQualifiers(), Loc,
1125                                                DS.TakeAttributes()));
1126    else
1127      // Remember that we parsed a Block type, and remember the type-quals.
1128      D.AddTypeInfo(DeclaratorChunk::getBlockPointer(DS.getTypeQualifiers(),
1129                                                     Loc));
1130  } else {
1131    // Is a reference
1132    DeclSpec DS;
1133
1134    // C++ 8.3.2p1: cv-qualified references are ill-formed except when the
1135    // cv-qualifiers are introduced through the use of a typedef or of a
1136    // template type argument, in which case the cv-qualifiers are ignored.
1137    //
1138    // [GNU] Retricted references are allowed.
1139    // [GNU] Attributes on references are allowed.
1140    ParseTypeQualifierListOpt(DS);
1141
1142    if (DS.getTypeQualifiers() != DeclSpec::TQ_unspecified) {
1143      if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
1144        Diag(DS.getConstSpecLoc(),
1145             diag::err_invalid_reference_qualifier_application,
1146             "const");
1147      if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
1148        Diag(DS.getVolatileSpecLoc(),
1149             diag::err_invalid_reference_qualifier_application,
1150             "volatile");
1151    }
1152
1153    // Recursively parse the declarator.
1154    ParseDeclaratorInternal(D);
1155
1156    // Remember that we parsed a reference type. It doesn't have type-quals.
1157    D.AddTypeInfo(DeclaratorChunk::getReference(DS.getTypeQualifiers(), Loc,
1158                                                DS.TakeAttributes()));
1159  }
1160}
1161
1162/// ParseDirectDeclarator
1163///       direct-declarator: [C99 6.7.5]
1164///         identifier
1165///         '(' declarator ')'
1166/// [GNU]   '(' attributes declarator ')'
1167/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1168/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1169/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1170/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1171/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1172///         direct-declarator '(' parameter-type-list ')'
1173///         direct-declarator '(' identifier-list[opt] ')'
1174/// [GNU]   direct-declarator '(' parameter-forward-declarations
1175///                    parameter-type-list[opt] ')'
1176///
1177void Parser::ParseDirectDeclarator(Declarator &D) {
1178  // Parse the first direct-declarator seen.
1179  if (Tok.is(tok::identifier) && D.mayHaveIdentifier()) {
1180    assert(Tok.getIdentifierInfo() && "Not an identifier?");
1181    D.SetIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1182    ConsumeToken();
1183  } else if (Tok.is(tok::l_paren)) {
1184    // direct-declarator: '(' declarator ')'
1185    // direct-declarator: '(' attributes declarator ')'
1186    // Example: 'char (*X)'   or 'int (*XX)(void)'
1187    ParseParenDeclarator(D);
1188  } else if (D.mayOmitIdentifier()) {
1189    // This could be something simple like "int" (in which case the declarator
1190    // portion is empty), if an abstract-declarator is allowed.
1191    D.SetIdentifier(0, Tok.getLocation());
1192  } else {
1193    // Expected identifier or '('.
1194    Diag(Tok, diag::err_expected_ident_lparen);
1195    D.SetIdentifier(0, Tok.getLocation());
1196  }
1197
1198  assert(D.isPastIdentifier() &&
1199         "Haven't past the location of the identifier yet?");
1200
1201  while (1) {
1202    if (Tok.is(tok::l_paren)) {
1203      ParseFunctionDeclarator(ConsumeParen(), D);
1204    } else if (Tok.is(tok::l_square)) {
1205      ParseBracketDeclarator(D);
1206    } else {
1207      break;
1208    }
1209  }
1210}
1211
1212/// ParseParenDeclarator - We parsed the declarator D up to a paren.  This is
1213/// only called before the identifier, so these are most likely just grouping
1214/// parens for precedence.  If we find that these are actually function
1215/// parameter parens in an abstract-declarator, we call ParseFunctionDeclarator.
1216///
1217///       direct-declarator:
1218///         '(' declarator ')'
1219/// [GNU]   '(' attributes declarator ')'
1220///
1221void Parser::ParseParenDeclarator(Declarator &D) {
1222  SourceLocation StartLoc = ConsumeParen();
1223  assert(!D.isPastIdentifier() && "Should be called before passing identifier");
1224
1225  // If we haven't past the identifier yet (or where the identifier would be
1226  // stored, if this is an abstract declarator), then this is probably just
1227  // grouping parens. However, if this could be an abstract-declarator, then
1228  // this could also be the start of function arguments (consider 'void()').
1229  bool isGrouping;
1230
1231  if (!D.mayOmitIdentifier()) {
1232    // If this can't be an abstract-declarator, this *must* be a grouping
1233    // paren, because we haven't seen the identifier yet.
1234    isGrouping = true;
1235  } else if (Tok.is(tok::r_paren) ||           // 'int()' is a function.
1236             isDeclarationSpecifier()) {       // 'int(int)' is a function.
1237    // This handles C99 6.7.5.3p11: in "typedef int X; void foo(X)", X is
1238    // considered to be a type, not a K&R identifier-list.
1239    isGrouping = false;
1240  } else {
1241    // Otherwise, this is a grouping paren, e.g. 'int (*X)' or 'int(X)'.
1242    isGrouping = true;
1243  }
1244
1245  // If this is a grouping paren, handle:
1246  // direct-declarator: '(' declarator ')'
1247  // direct-declarator: '(' attributes declarator ')'
1248  if (isGrouping) {
1249    if (Tok.is(tok::kw___attribute))
1250      D.AddAttributes(ParseAttributes());
1251
1252    ParseDeclaratorInternal(D);
1253    // Match the ')'.
1254    MatchRHSPunctuation(tok::r_paren, StartLoc);
1255    return;
1256  }
1257
1258  // Okay, if this wasn't a grouping paren, it must be the start of a function
1259  // argument list.  Recognize that this declarator will never have an
1260  // identifier (and remember where it would have been), then fall through to
1261  // the handling of argument lists.
1262  D.SetIdentifier(0, Tok.getLocation());
1263
1264  ParseFunctionDeclarator(StartLoc, D);
1265}
1266
1267/// ParseFunctionDeclarator - We are after the identifier and have parsed the
1268/// declarator D up to a paren, which indicates that we are parsing function
1269/// arguments.
1270///
1271/// This method also handles this portion of the grammar:
1272///       parameter-type-list: [C99 6.7.5]
1273///         parameter-list
1274///         parameter-list ',' '...'
1275///
1276///       parameter-list: [C99 6.7.5]
1277///         parameter-declaration
1278///         parameter-list ',' parameter-declaration
1279///
1280///       parameter-declaration: [C99 6.7.5]
1281///         declaration-specifiers declarator
1282/// [C++]   declaration-specifiers declarator '=' assignment-expression
1283/// [GNU]   declaration-specifiers declarator attributes
1284///         declaration-specifiers abstract-declarator[opt]
1285/// [C++]   declaration-specifiers abstract-declarator[opt]
1286///           '=' assignment-expression
1287/// [GNU]   declaration-specifiers abstract-declarator[opt] attributes
1288///
1289void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D) {
1290  // lparen is already consumed!
1291  assert(D.isPastIdentifier() && "Should not call before identifier!");
1292
1293  // Okay, this is the parameter list of a function definition, or it is an
1294  // identifier list of a K&R-style function.
1295
1296  if (Tok.is(tok::r_paren)) {
1297    // Remember that we parsed a function type, and remember the attributes.
1298    // int() -> no prototype, no '...'.
1299    D.AddTypeInfo(DeclaratorChunk::getFunction(/*prototype*/ false,
1300                                               /*variadic*/ false,
1301                                               /*arglist*/ 0, 0, LParenLoc));
1302
1303    ConsumeParen();  // Eat the closing ')'.
1304    return;
1305  } else if (Tok.is(tok::identifier) &&
1306             // K&R identifier lists can't have typedefs as identifiers, per
1307             // C99 6.7.5.3p11.
1308             !Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope)) {
1309    // Identifier list.  Note that '(' identifier-list ')' is only allowed for
1310    // normal declarators, not for abstract-declarators.
1311    return ParseFunctionDeclaratorIdentifierList(LParenLoc, D);
1312  }
1313
1314  // Finally, a normal, non-empty parameter type list.
1315
1316  // Build up an array of information about the parsed arguments.
1317  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1318
1319  // Enter function-declaration scope, limiting any declarators to the
1320  // function prototype scope, including parameter declarators.
1321  EnterScope(Scope::FnScope|Scope::DeclScope);
1322
1323  bool IsVariadic = false;
1324  while (1) {
1325    if (Tok.is(tok::ellipsis)) {
1326      IsVariadic = true;
1327
1328      // Check to see if this is "void(...)" which is not allowed.
1329      if (ParamInfo.empty()) {
1330        // Otherwise, parse parameter type list.  If it starts with an
1331        // ellipsis,  diagnose the malformed function.
1332        Diag(Tok, diag::err_ellipsis_first_arg);
1333        IsVariadic = false;       // Treat this like 'void()'.
1334      }
1335
1336      ConsumeToken();     // Consume the ellipsis.
1337      break;
1338    }
1339
1340    SourceLocation DSStart = Tok.getLocation();
1341
1342    // Parse the declaration-specifiers.
1343    DeclSpec DS;
1344    ParseDeclarationSpecifiers(DS);
1345
1346    // Parse the declarator.  This is "PrototypeContext", because we must
1347    // accept either 'declarator' or 'abstract-declarator' here.
1348    Declarator ParmDecl(DS, Declarator::PrototypeContext);
1349    ParseDeclarator(ParmDecl);
1350
1351    // Parse GNU attributes, if present.
1352    if (Tok.is(tok::kw___attribute))
1353      ParmDecl.AddAttributes(ParseAttributes());
1354
1355    // Remember this parsed parameter in ParamInfo.
1356    IdentifierInfo *ParmII = ParmDecl.getIdentifier();
1357
1358    // If no parameter was specified, verify that *something* was specified,
1359    // otherwise we have a missing type and identifier.
1360    if (DS.getParsedSpecifiers() == DeclSpec::PQ_None &&
1361        ParmDecl.getIdentifier() == 0 && ParmDecl.getNumTypeObjects() == 0) {
1362      // Completely missing, emit error.
1363      Diag(DSStart, diag::err_missing_param);
1364    } else {
1365      // Otherwise, we have something.  Add it and let semantic analysis try
1366      // to grok it and add the result to the ParamInfo we are building.
1367
1368      // Inform the actions module about the parameter declarator, so it gets
1369      // added to the current scope.
1370      DeclTy *Param = Actions.ActOnParamDeclarator(CurScope, ParmDecl);
1371
1372      // Parse the default argument, if any. We parse the default
1373      // arguments in all dialects; the semantic analysis in
1374      // ActOnParamDefaultArgument will reject the default argument in
1375      // C.
1376      if (Tok.is(tok::equal)) {
1377        SourceLocation EqualLoc = Tok.getLocation();
1378
1379        // Consume the '='.
1380        ConsumeToken();
1381
1382        // Parse the default argument
1383        ExprResult DefArgResult = ParseAssignmentExpression();
1384        if (DefArgResult.isInvalid) {
1385          SkipUntil(tok::comma, tok::r_paren, true, true);
1386        } else {
1387          // Inform the actions module about the default argument
1388          Actions.ActOnParamDefaultArgument(Param, EqualLoc, DefArgResult.Val);
1389        }
1390      }
1391
1392      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1393                             ParmDecl.getIdentifierLoc(), Param));
1394    }
1395
1396    // If the next token is a comma, consume it and keep reading arguments.
1397    if (Tok.isNot(tok::comma)) break;
1398
1399    // Consume the comma.
1400    ConsumeToken();
1401  }
1402
1403  // Leave prototype scope.
1404  ExitScope();
1405
1406  // Remember that we parsed a function type, and remember the attributes.
1407  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/true, IsVariadic,
1408                                             &ParamInfo[0], ParamInfo.size(),
1409                                             LParenLoc));
1410
1411  // If we have the closing ')', eat it and we're done.
1412  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1413}
1414
1415/// ParseFunctionDeclaratorIdentifierList - While parsing a function declarator
1416/// we found a K&R-style identifier list instead of a type argument list.  The
1417/// current token is known to be the first identifier in the list.
1418///
1419///       identifier-list: [C99 6.7.5]
1420///         identifier
1421///         identifier-list ',' identifier
1422///
1423void Parser::ParseFunctionDeclaratorIdentifierList(SourceLocation LParenLoc,
1424                                                   Declarator &D) {
1425  // Build up an array of information about the parsed arguments.
1426  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1427  llvm::SmallSet<const IdentifierInfo*, 16> ParamsSoFar;
1428
1429  // If there was no identifier specified for the declarator, either we are in
1430  // an abstract-declarator, or we are in a parameter declarator which was found
1431  // to be abstract.  In abstract-declarators, identifier lists are not valid:
1432  // diagnose this.
1433  if (!D.getIdentifier())
1434    Diag(Tok, diag::ext_ident_list_in_param);
1435
1436  // Tok is known to be the first identifier in the list.  Remember this
1437  // identifier in ParamInfo.
1438  ParamsSoFar.insert(Tok.getIdentifierInfo());
1439  ParamInfo.push_back(DeclaratorChunk::ParamInfo(Tok.getIdentifierInfo(),
1440                                                 Tok.getLocation(), 0));
1441
1442  ConsumeToken();  // eat the first identifier.
1443
1444  while (Tok.is(tok::comma)) {
1445    // Eat the comma.
1446    ConsumeToken();
1447
1448    // If this isn't an identifier, report the error and skip until ')'.
1449    if (Tok.isNot(tok::identifier)) {
1450      Diag(Tok, diag::err_expected_ident);
1451      SkipUntil(tok::r_paren);
1452      return;
1453    }
1454
1455    IdentifierInfo *ParmII = Tok.getIdentifierInfo();
1456
1457    // Reject 'typedef int y; int test(x, y)', but continue parsing.
1458    if (Actions.isTypeName(*ParmII, CurScope))
1459      Diag(Tok, diag::err_unexpected_typedef_ident, ParmII->getName());
1460
1461    // Verify that the argument identifier has not already been mentioned.
1462    if (!ParamsSoFar.insert(ParmII)) {
1463      Diag(Tok.getLocation(), diag::err_param_redefinition, ParmII->getName());
1464    } else {
1465      // Remember this identifier in ParamInfo.
1466      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1467                                                     Tok.getLocation(), 0));
1468    }
1469
1470    // Eat the identifier.
1471    ConsumeToken();
1472  }
1473
1474  // Remember that we parsed a function type, and remember the attributes.  This
1475  // function type is always a K&R style function type, which is not varargs and
1476  // has no prototype.
1477  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/false, /*varargs*/false,
1478                                             &ParamInfo[0], ParamInfo.size(),
1479                                             LParenLoc));
1480
1481  // If we have the closing ')', eat it and we're done.
1482  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1483}
1484
1485/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1486/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1487/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1488/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1489/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1490void Parser::ParseBracketDeclarator(Declarator &D) {
1491  SourceLocation StartLoc = ConsumeBracket();
1492
1493  // If valid, this location is the position where we read the 'static' keyword.
1494  SourceLocation StaticLoc;
1495  if (Tok.is(tok::kw_static))
1496    StaticLoc = ConsumeToken();
1497
1498  // If there is a type-qualifier-list, read it now.
1499  DeclSpec DS;
1500  ParseTypeQualifierListOpt(DS);
1501
1502  // If we haven't already read 'static', check to see if there is one after the
1503  // type-qualifier-list.
1504  if (!StaticLoc.isValid() && Tok.is(tok::kw_static))
1505    StaticLoc = ConsumeToken();
1506
1507  // Handle "direct-declarator [ type-qual-list[opt] * ]".
1508  bool isStar = false;
1509  ExprResult NumElements(false);
1510
1511  // Handle the case where we have '[*]' as the array size.  However, a leading
1512  // star could be the start of an expression, for example 'X[*p + 4]'.  Verify
1513  // the the token after the star is a ']'.  Since stars in arrays are
1514  // infrequent, use of lookahead is not costly here.
1515  if (Tok.is(tok::star) && GetLookAheadToken(1).is(tok::r_square)) {
1516    ConsumeToken();  // Eat the '*'.
1517
1518    if (StaticLoc.isValid())
1519      Diag(StaticLoc, diag::err_unspecified_vla_size_with_static);
1520    StaticLoc = SourceLocation();  // Drop the static.
1521    isStar = true;
1522  } else if (Tok.isNot(tok::r_square)) {
1523    // Parse the assignment-expression now.
1524    NumElements = ParseAssignmentExpression();
1525  }
1526
1527  // If there was an error parsing the assignment-expression, recover.
1528  if (NumElements.isInvalid) {
1529    // If the expression was invalid, skip it.
1530    SkipUntil(tok::r_square);
1531    return;
1532  }
1533
1534  MatchRHSPunctuation(tok::r_square, StartLoc);
1535
1536  // If C99 isn't enabled, emit an ext-warn if the arg list wasn't empty and if
1537  // it was not a constant expression.
1538  if (!getLang().C99) {
1539    // TODO: check C90 array constant exprness.
1540    if (isStar || StaticLoc.isValid() ||
1541        0/*TODO: NumElts is not a C90 constantexpr */)
1542      Diag(StartLoc, diag::ext_c99_array_usage);
1543  }
1544
1545  // Remember that we parsed a pointer type, and remember the type-quals.
1546  D.AddTypeInfo(DeclaratorChunk::getArray(DS.getTypeQualifiers(),
1547                                          StaticLoc.isValid(), isStar,
1548                                          NumElements.Val, StartLoc));
1549}
1550
1551/// [GNU]   typeof-specifier:
1552///           typeof ( expressions )
1553///           typeof ( type-name )
1554/// [GNU/C++] typeof unary-expression
1555///
1556void Parser::ParseTypeofSpecifier(DeclSpec &DS) {
1557  assert(Tok.is(tok::kw_typeof) && "Not a typeof specifier");
1558  const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo();
1559  SourceLocation StartLoc = ConsumeToken();
1560
1561  if (Tok.isNot(tok::l_paren)) {
1562    if (!getLang().CPlusPlus) {
1563      Diag(Tok, diag::err_expected_lparen_after, BuiltinII->getName());
1564      return;
1565    }
1566
1567    ExprResult Result = ParseCastExpression(true/*isUnaryExpression*/);
1568    if (Result.isInvalid)
1569      return;
1570
1571    const char *PrevSpec = 0;
1572    // Check for duplicate type specifiers.
1573    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
1574                           Result.Val))
1575      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1576
1577    // FIXME: Not accurate, the range gets one token more than it should.
1578    DS.SetRangeEnd(Tok.getLocation());
1579    return;
1580  }
1581
1582  SourceLocation LParenLoc = ConsumeParen(), RParenLoc;
1583
1584  if (isTypeSpecifierQualifier()) {
1585    TypeTy *Ty = ParseTypeName();
1586
1587    assert(Ty && "Parser::ParseTypeofSpecifier(): missing type");
1588
1589    if (Tok.isNot(tok::r_paren)) {
1590      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1591      return;
1592    }
1593    RParenLoc = ConsumeParen();
1594    const char *PrevSpec = 0;
1595    // Check for duplicate type specifiers (e.g. "int typeof(int)").
1596    if (DS.SetTypeSpecType(DeclSpec::TST_typeofType, StartLoc, PrevSpec, Ty))
1597      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1598  } else { // we have an expression.
1599    ExprResult Result = ParseExpression();
1600
1601    if (Result.isInvalid || Tok.isNot(tok::r_paren)) {
1602      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1603      return;
1604    }
1605    RParenLoc = ConsumeParen();
1606    const char *PrevSpec = 0;
1607    // Check for duplicate type specifiers (e.g. "int typeof(int)").
1608    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
1609                           Result.Val))
1610      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1611  }
1612  DS.SetRangeEnd(RParenLoc);
1613}
1614
1615
1616