ParseDecl.cpp revision e281b4cb3c2f85e10412040b35c2699bc883b716 
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      // Do not allow any other declspecs after the protocol qualifier list
449      // "<foo,bar>short" is not allowed.
450      goto DoneWithDeclSpec;
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        // Do not allow any other declspecs after the protocol qualifier list
589        // "<foo,bar>short" is not allowed.
590        goto DoneWithDeclSpec;
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  Actions.ActOnFields(CurScope,
768                      RecordLoc,TagDecl,&FieldDecls[0],FieldDecls.size(),
769                      LBraceLoc, RBraceLoc);
770
771  AttributeList *AttrList = 0;
772  // If attributes exist after struct contents, parse them.
773  if (Tok.is(tok::kw___attribute))
774    AttrList = ParseAttributes(); // FIXME: where should I put them?
775}
776
777
778/// ParseEnumSpecifier
779///       enum-specifier: [C99 6.7.2.2]
780///         'enum' identifier[opt] '{' enumerator-list '}'
781/// [C99]   'enum' identifier[opt] '{' enumerator-list ',' '}'
782/// [GNU]   'enum' attributes[opt] identifier[opt] '{' enumerator-list ',' [opt]
783///                                                 '}' attributes[opt]
784///         'enum' identifier
785/// [GNU]   'enum' attributes[opt] identifier
786void Parser::ParseEnumSpecifier(DeclSpec &DS) {
787  assert(Tok.is(tok::kw_enum) && "Not an enum specifier");
788  SourceLocation StartLoc = ConsumeToken();
789
790  // Parse the tag portion of this.
791
792  AttributeList *Attr = 0;
793  // If attributes exist after tag, parse them.
794  if (Tok.is(tok::kw___attribute))
795    Attr = ParseAttributes();
796
797  // Must have either 'enum name' or 'enum {...}'.
798  if (Tok.isNot(tok::identifier) && Tok.isNot(tok::l_brace)) {
799    Diag(Tok, diag::err_expected_ident_lbrace);
800
801    // Skip the rest of this declarator, up until the comma or semicolon.
802    SkipUntil(tok::comma, true);
803    return;
804  }
805
806  // If an identifier is present, consume and remember it.
807  IdentifierInfo *Name = 0;
808  SourceLocation NameLoc;
809  if (Tok.is(tok::identifier)) {
810    Name = Tok.getIdentifierInfo();
811    NameLoc = ConsumeToken();
812  }
813
814  // There are three options here.  If we have 'enum foo;', then this is a
815  // forward declaration.  If we have 'enum foo {...' then this is a
816  // definition. Otherwise we have something like 'enum foo xyz', a reference.
817  //
818  // This is needed to handle stuff like this right (C99 6.7.2.3p11):
819  // enum foo {..};  void bar() { enum foo; }    <- new foo in bar.
820  // enum foo {..};  void bar() { enum foo x; }  <- use of old foo.
821  //
822  Action::TagKind TK;
823  if (Tok.is(tok::l_brace))
824    TK = Action::TK_Definition;
825  else if (Tok.is(tok::semi))
826    TK = Action::TK_Declaration;
827  else
828    TK = Action::TK_Reference;
829  DeclTy *TagDecl = Actions.ActOnTag(CurScope, DeclSpec::TST_enum, TK, StartLoc,
830                                     Name, NameLoc, Attr);
831
832  if (Tok.is(tok::l_brace))
833    ParseEnumBody(StartLoc, TagDecl);
834
835  // TODO: semantic analysis on the declspec for enums.
836  const char *PrevSpec = 0;
837  if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc, PrevSpec, TagDecl))
838    Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
839}
840
841/// ParseEnumBody - Parse a {} enclosed enumerator-list.
842///       enumerator-list:
843///         enumerator
844///         enumerator-list ',' enumerator
845///       enumerator:
846///         enumeration-constant
847///         enumeration-constant '=' constant-expression
848///       enumeration-constant:
849///         identifier
850///
851void Parser::ParseEnumBody(SourceLocation StartLoc, DeclTy *EnumDecl) {
852  SourceLocation LBraceLoc = ConsumeBrace();
853
854  // C does not allow an empty enumerator-list, C++ does [dcl.enum].
855  if (Tok.is(tok::r_brace) && !getLang().CPlusPlus)
856    Diag(Tok, diag::ext_empty_struct_union_enum, "enum");
857
858  llvm::SmallVector<DeclTy*, 32> EnumConstantDecls;
859
860  DeclTy *LastEnumConstDecl = 0;
861
862  // Parse the enumerator-list.
863  while (Tok.is(tok::identifier)) {
864    IdentifierInfo *Ident = Tok.getIdentifierInfo();
865    SourceLocation IdentLoc = ConsumeToken();
866
867    SourceLocation EqualLoc;
868    ExprTy *AssignedVal = 0;
869    if (Tok.is(tok::equal)) {
870      EqualLoc = ConsumeToken();
871      ExprResult Res = ParseConstantExpression();
872      if (Res.isInvalid)
873        SkipUntil(tok::comma, tok::r_brace, true, true);
874      else
875        AssignedVal = Res.Val;
876    }
877
878    // Install the enumerator constant into EnumDecl.
879    DeclTy *EnumConstDecl = Actions.ActOnEnumConstant(CurScope, EnumDecl,
880                                                      LastEnumConstDecl,
881                                                      IdentLoc, Ident,
882                                                      EqualLoc, AssignedVal);
883    EnumConstantDecls.push_back(EnumConstDecl);
884    LastEnumConstDecl = EnumConstDecl;
885
886    if (Tok.isNot(tok::comma))
887      break;
888    SourceLocation CommaLoc = ConsumeToken();
889
890    if (Tok.isNot(tok::identifier) && !getLang().C99)
891      Diag(CommaLoc, diag::ext_c99_enumerator_list_comma);
892  }
893
894  // Eat the }.
895  MatchRHSPunctuation(tok::r_brace, LBraceLoc);
896
897  Actions.ActOnEnumBody(StartLoc, EnumDecl, &EnumConstantDecls[0],
898                        EnumConstantDecls.size());
899
900  DeclTy *AttrList = 0;
901  // If attributes exist after the identifier list, parse them.
902  if (Tok.is(tok::kw___attribute))
903    AttrList = ParseAttributes(); // FIXME: where do they do?
904}
905
906/// isTypeSpecifierQualifier - Return true if the current token could be the
907/// start of a type-qualifier-list.
908bool Parser::isTypeQualifier() const {
909  switch (Tok.getKind()) {
910  default: return false;
911    // type-qualifier
912  case tok::kw_const:
913  case tok::kw_volatile:
914  case tok::kw_restrict:
915    return true;
916  }
917}
918
919/// isTypeSpecifierQualifier - Return true if the current token could be the
920/// start of a specifier-qualifier-list.
921bool Parser::isTypeSpecifierQualifier() const {
922  switch (Tok.getKind()) {
923  default: return false;
924    // GNU attributes support.
925  case tok::kw___attribute:
926    // GNU typeof support.
927  case tok::kw_typeof:
928    // GNU bizarre protocol extension. FIXME: make an extension?
929  case tok::less:
930
931    // type-specifiers
932  case tok::kw_short:
933  case tok::kw_long:
934  case tok::kw_signed:
935  case tok::kw_unsigned:
936  case tok::kw__Complex:
937  case tok::kw__Imaginary:
938  case tok::kw_void:
939  case tok::kw_char:
940  case tok::kw_wchar_t:
941  case tok::kw_int:
942  case tok::kw_float:
943  case tok::kw_double:
944  case tok::kw_bool:
945  case tok::kw__Bool:
946  case tok::kw__Decimal32:
947  case tok::kw__Decimal64:
948  case tok::kw__Decimal128:
949
950    // struct-or-union-specifier (C99) or class-specifier (C++)
951  case tok::kw_class:
952  case tok::kw_struct:
953  case tok::kw_union:
954    // enum-specifier
955  case tok::kw_enum:
956
957    // type-qualifier
958  case tok::kw_const:
959  case tok::kw_volatile:
960  case tok::kw_restrict:
961    return true;
962
963    // typedef-name
964  case tok::identifier:
965    return Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope) != 0;
966  }
967}
968
969/// isDeclarationSpecifier() - Return true if the current token is part of a
970/// declaration specifier.
971bool Parser::isDeclarationSpecifier() const {
972  switch (Tok.getKind()) {
973  default: return false;
974    // storage-class-specifier
975  case tok::kw_typedef:
976  case tok::kw_extern:
977  case tok::kw___private_extern__:
978  case tok::kw_static:
979  case tok::kw_auto:
980  case tok::kw_register:
981  case tok::kw___thread:
982
983    // type-specifiers
984  case tok::kw_short:
985  case tok::kw_long:
986  case tok::kw_signed:
987  case tok::kw_unsigned:
988  case tok::kw__Complex:
989  case tok::kw__Imaginary:
990  case tok::kw_void:
991  case tok::kw_char:
992  case tok::kw_wchar_t:
993  case tok::kw_int:
994  case tok::kw_float:
995  case tok::kw_double:
996  case tok::kw_bool:
997  case tok::kw__Bool:
998  case tok::kw__Decimal32:
999  case tok::kw__Decimal64:
1000  case tok::kw__Decimal128:
1001
1002    // struct-or-union-specifier (C99) or class-specifier (C++)
1003  case tok::kw_class:
1004  case tok::kw_struct:
1005  case tok::kw_union:
1006    // enum-specifier
1007  case tok::kw_enum:
1008
1009    // type-qualifier
1010  case tok::kw_const:
1011  case tok::kw_volatile:
1012  case tok::kw_restrict:
1013
1014    // function-specifier
1015  case tok::kw_inline:
1016
1017    // GNU typeof support.
1018  case tok::kw_typeof:
1019
1020    // GNU attributes.
1021  case tok::kw___attribute:
1022    return true;
1023
1024    // GNU ObjC bizarre protocol extension: <proto1,proto2> with implicit 'id'.
1025  case tok::less:
1026    return getLang().ObjC1;
1027
1028    // typedef-name
1029  case tok::identifier:
1030    return Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope) != 0;
1031  }
1032}
1033
1034
1035/// ParseTypeQualifierListOpt
1036///       type-qualifier-list: [C99 6.7.5]
1037///         type-qualifier
1038/// [GNU]   attributes
1039///         type-qualifier-list type-qualifier
1040/// [GNU]   type-qualifier-list attributes
1041///
1042void Parser::ParseTypeQualifierListOpt(DeclSpec &DS) {
1043  while (1) {
1044    int isInvalid = false;
1045    const char *PrevSpec = 0;
1046    SourceLocation Loc = Tok.getLocation();
1047
1048    switch (Tok.getKind()) {
1049    default:
1050      // If this is not a type-qualifier token, we're done reading type
1051      // qualifiers.  First verify that DeclSpec's are consistent.
1052      DS.Finish(Diags, PP.getSourceManager(), getLang());
1053      return;
1054    case tok::kw_const:
1055      isInvalid = DS.SetTypeQual(DeclSpec::TQ_const   , Loc, PrevSpec,
1056                                 getLang())*2;
1057      break;
1058    case tok::kw_volatile:
1059      isInvalid = DS.SetTypeQual(DeclSpec::TQ_volatile, Loc, PrevSpec,
1060                                 getLang())*2;
1061      break;
1062    case tok::kw_restrict:
1063      isInvalid = DS.SetTypeQual(DeclSpec::TQ_restrict, Loc, PrevSpec,
1064                                 getLang())*2;
1065      break;
1066    case tok::kw___attribute:
1067      DS.AddAttributes(ParseAttributes());
1068      continue; // do *not* consume the next token!
1069    }
1070
1071    // If the specifier combination wasn't legal, issue a diagnostic.
1072    if (isInvalid) {
1073      assert(PrevSpec && "Method did not return previous specifier!");
1074      if (isInvalid == 1)  // Error.
1075        Diag(Tok, diag::err_invalid_decl_spec_combination, PrevSpec);
1076      else                 // extwarn.
1077        Diag(Tok, diag::ext_duplicate_declspec, PrevSpec);
1078    }
1079    ConsumeToken();
1080  }
1081}
1082
1083
1084/// ParseDeclarator - Parse and verify a newly-initialized declarator.
1085///
1086void Parser::ParseDeclarator(Declarator &D) {
1087  /// This implements the 'declarator' production in the C grammar, then checks
1088  /// for well-formedness and issues diagnostics.
1089  ParseDeclaratorInternal(D);
1090}
1091
1092/// ParseDeclaratorInternal
1093///       declarator: [C99 6.7.5]
1094///         pointer[opt] direct-declarator
1095/// [C++]   '&' declarator [C++ 8p4, dcl.decl]
1096/// [GNU]   '&' restrict[opt] attributes[opt] declarator
1097///
1098///       pointer: [C99 6.7.5]
1099///         '*' type-qualifier-list[opt]
1100///         '*' type-qualifier-list[opt] pointer
1101///
1102void Parser::ParseDeclaratorInternal(Declarator &D) {
1103  tok::TokenKind Kind = Tok.getKind();
1104
1105  // Not a pointer, C++ reference, or block.
1106  if (Kind != tok::star && (Kind != tok::amp || !getLang().CPlusPlus) &&
1107      (Kind != tok::caret || !getLang().Blocks))
1108    return ParseDirectDeclarator(D);
1109
1110  // Otherwise, '*' -> pointer, '^' -> block, '&' -> reference.
1111  SourceLocation Loc = ConsumeToken();  // Eat the * or &.
1112
1113  if (Kind == tok::star || (Kind == tok::caret && getLang().Blocks)) {
1114    // Is a pointer.
1115    DeclSpec DS;
1116
1117    ParseTypeQualifierListOpt(DS);
1118
1119    // Recursively parse the declarator.
1120    ParseDeclaratorInternal(D);
1121    if (Kind == tok::star)
1122      // Remember that we parsed a pointer type, and remember the type-quals.
1123      D.AddTypeInfo(DeclaratorChunk::getPointer(DS.getTypeQualifiers(), Loc,
1124                                                DS.TakeAttributes()));
1125    else
1126      // Remember that we parsed a Block type, and remember the type-quals.
1127      D.AddTypeInfo(DeclaratorChunk::getBlockPointer(DS.getTypeQualifiers(),
1128                                                     Loc));
1129  } else {
1130    // Is a reference
1131    DeclSpec DS;
1132
1133    // C++ 8.3.2p1: cv-qualified references are ill-formed except when the
1134    // cv-qualifiers are introduced through the use of a typedef or of a
1135    // template type argument, in which case the cv-qualifiers are ignored.
1136    //
1137    // [GNU] Retricted references are allowed.
1138    // [GNU] Attributes on references are allowed.
1139    ParseTypeQualifierListOpt(DS);
1140
1141    if (DS.getTypeQualifiers() != DeclSpec::TQ_unspecified) {
1142      if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
1143        Diag(DS.getConstSpecLoc(),
1144             diag::err_invalid_reference_qualifier_application,
1145             "const");
1146      if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
1147        Diag(DS.getVolatileSpecLoc(),
1148             diag::err_invalid_reference_qualifier_application,
1149             "volatile");
1150    }
1151
1152    // Recursively parse the declarator.
1153    ParseDeclaratorInternal(D);
1154
1155    // Remember that we parsed a reference type. It doesn't have type-quals.
1156    D.AddTypeInfo(DeclaratorChunk::getReference(DS.getTypeQualifiers(), Loc,
1157                                                DS.TakeAttributes()));
1158  }
1159}
1160
1161/// ParseDirectDeclarator
1162///       direct-declarator: [C99 6.7.5]
1163///         identifier
1164///         '(' declarator ')'
1165/// [GNU]   '(' attributes declarator ')'
1166/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1167/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1168/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1169/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1170/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1171///         direct-declarator '(' parameter-type-list ')'
1172///         direct-declarator '(' identifier-list[opt] ')'
1173/// [GNU]   direct-declarator '(' parameter-forward-declarations
1174///                    parameter-type-list[opt] ')'
1175///
1176void Parser::ParseDirectDeclarator(Declarator &D) {
1177  // Parse the first direct-declarator seen.
1178  if (Tok.is(tok::identifier) && D.mayHaveIdentifier()) {
1179    assert(Tok.getIdentifierInfo() && "Not an identifier?");
1180    D.SetIdentifier(Tok.getIdentifierInfo(), Tok.getLocation());
1181    ConsumeToken();
1182  } else if (Tok.is(tok::l_paren)) {
1183    // direct-declarator: '(' declarator ')'
1184    // direct-declarator: '(' attributes declarator ')'
1185    // Example: 'char (*X)'   or 'int (*XX)(void)'
1186    ParseParenDeclarator(D);
1187  } else if (D.mayOmitIdentifier()) {
1188    // This could be something simple like "int" (in which case the declarator
1189    // portion is empty), if an abstract-declarator is allowed.
1190    D.SetIdentifier(0, Tok.getLocation());
1191  } else {
1192    // Expected identifier or '('.
1193    Diag(Tok, diag::err_expected_ident_lparen);
1194    D.SetIdentifier(0, Tok.getLocation());
1195  }
1196
1197  assert(D.isPastIdentifier() &&
1198         "Haven't past the location of the identifier yet?");
1199
1200  while (1) {
1201    if (Tok.is(tok::l_paren)) {
1202      ParseFunctionDeclarator(ConsumeParen(), D);
1203    } else if (Tok.is(tok::l_square)) {
1204      ParseBracketDeclarator(D);
1205    } else {
1206      break;
1207    }
1208  }
1209}
1210
1211/// ParseParenDeclarator - We parsed the declarator D up to a paren.  This is
1212/// only called before the identifier, so these are most likely just grouping
1213/// parens for precedence.  If we find that these are actually function
1214/// parameter parens in an abstract-declarator, we call ParseFunctionDeclarator.
1215///
1216///       direct-declarator:
1217///         '(' declarator ')'
1218/// [GNU]   '(' attributes declarator ')'
1219///
1220void Parser::ParseParenDeclarator(Declarator &D) {
1221  SourceLocation StartLoc = ConsumeParen();
1222  assert(!D.isPastIdentifier() && "Should be called before passing identifier");
1223
1224  // If we haven't past the identifier yet (or where the identifier would be
1225  // stored, if this is an abstract declarator), then this is probably just
1226  // grouping parens. However, if this could be an abstract-declarator, then
1227  // this could also be the start of function arguments (consider 'void()').
1228  bool isGrouping;
1229
1230  if (!D.mayOmitIdentifier()) {
1231    // If this can't be an abstract-declarator, this *must* be a grouping
1232    // paren, because we haven't seen the identifier yet.
1233    isGrouping = true;
1234  } else if (Tok.is(tok::r_paren) ||           // 'int()' is a function.
1235             isDeclarationSpecifier()) {       // 'int(int)' is a function.
1236    // This handles C99 6.7.5.3p11: in "typedef int X; void foo(X)", X is
1237    // considered to be a type, not a K&R identifier-list.
1238    isGrouping = false;
1239  } else {
1240    // Otherwise, this is a grouping paren, e.g. 'int (*X)' or 'int(X)'.
1241    isGrouping = true;
1242  }
1243
1244  // If this is a grouping paren, handle:
1245  // direct-declarator: '(' declarator ')'
1246  // direct-declarator: '(' attributes declarator ')'
1247  if (isGrouping) {
1248    if (Tok.is(tok::kw___attribute))
1249      D.AddAttributes(ParseAttributes());
1250
1251    ParseDeclaratorInternal(D);
1252    // Match the ')'.
1253    MatchRHSPunctuation(tok::r_paren, StartLoc);
1254    return;
1255  }
1256
1257  // Okay, if this wasn't a grouping paren, it must be the start of a function
1258  // argument list.  Recognize that this declarator will never have an
1259  // identifier (and remember where it would have been), then fall through to
1260  // the handling of argument lists.
1261  D.SetIdentifier(0, Tok.getLocation());
1262
1263  ParseFunctionDeclarator(StartLoc, D);
1264}
1265
1266/// ParseFunctionDeclarator - We are after the identifier and have parsed the
1267/// declarator D up to a paren, which indicates that we are parsing function
1268/// arguments.
1269///
1270/// This method also handles this portion of the grammar:
1271///       parameter-type-list: [C99 6.7.5]
1272///         parameter-list
1273///         parameter-list ',' '...'
1274///
1275///       parameter-list: [C99 6.7.5]
1276///         parameter-declaration
1277///         parameter-list ',' parameter-declaration
1278///
1279///       parameter-declaration: [C99 6.7.5]
1280///         declaration-specifiers declarator
1281/// [C++]   declaration-specifiers declarator '=' assignment-expression
1282/// [GNU]   declaration-specifiers declarator attributes
1283///         declaration-specifiers abstract-declarator[opt]
1284/// [C++]   declaration-specifiers abstract-declarator[opt]
1285///           '=' assignment-expression
1286/// [GNU]   declaration-specifiers abstract-declarator[opt] attributes
1287///
1288void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D) {
1289  // lparen is already consumed!
1290  assert(D.isPastIdentifier() && "Should not call before identifier!");
1291
1292  // Okay, this is the parameter list of a function definition, or it is an
1293  // identifier list of a K&R-style function.
1294
1295  if (Tok.is(tok::r_paren)) {
1296    // Remember that we parsed a function type, and remember the attributes.
1297    // int() -> no prototype, no '...'.
1298    D.AddTypeInfo(DeclaratorChunk::getFunction(/*prototype*/ false,
1299                                               /*variadic*/ false,
1300                                               /*arglist*/ 0, 0, LParenLoc));
1301
1302    ConsumeParen();  // Eat the closing ')'.
1303    return;
1304  } else if (Tok.is(tok::identifier) &&
1305             // K&R identifier lists can't have typedefs as identifiers, per
1306             // C99 6.7.5.3p11.
1307             !Actions.isTypeName(*Tok.getIdentifierInfo(), CurScope)) {
1308    // Identifier list.  Note that '(' identifier-list ')' is only allowed for
1309    // normal declarators, not for abstract-declarators.
1310    return ParseFunctionDeclaratorIdentifierList(LParenLoc, D);
1311  }
1312
1313  // Finally, a normal, non-empty parameter type list.
1314
1315  // Build up an array of information about the parsed arguments.
1316  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1317
1318  // Enter function-declaration scope, limiting any declarators to the
1319  // function prototype scope, including parameter declarators.
1320  EnterScope(Scope::FnScope|Scope::DeclScope);
1321
1322  bool IsVariadic = false;
1323  while (1) {
1324    if (Tok.is(tok::ellipsis)) {
1325      IsVariadic = true;
1326
1327      // Check to see if this is "void(...)" which is not allowed.
1328      if (ParamInfo.empty()) {
1329        // Otherwise, parse parameter type list.  If it starts with an
1330        // ellipsis,  diagnose the malformed function.
1331        Diag(Tok, diag::err_ellipsis_first_arg);
1332        IsVariadic = false;       // Treat this like 'void()'.
1333      }
1334
1335      ConsumeToken();     // Consume the ellipsis.
1336      break;
1337    }
1338
1339    SourceLocation DSStart = Tok.getLocation();
1340
1341    // Parse the declaration-specifiers.
1342    DeclSpec DS;
1343    ParseDeclarationSpecifiers(DS);
1344
1345    // Parse the declarator.  This is "PrototypeContext", because we must
1346    // accept either 'declarator' or 'abstract-declarator' here.
1347    Declarator ParmDecl(DS, Declarator::PrototypeContext);
1348    ParseDeclarator(ParmDecl);
1349
1350    // Parse GNU attributes, if present.
1351    if (Tok.is(tok::kw___attribute))
1352      ParmDecl.AddAttributes(ParseAttributes());
1353
1354    // Remember this parsed parameter in ParamInfo.
1355    IdentifierInfo *ParmII = ParmDecl.getIdentifier();
1356
1357    // If no parameter was specified, verify that *something* was specified,
1358    // otherwise we have a missing type and identifier.
1359    if (DS.getParsedSpecifiers() == DeclSpec::PQ_None &&
1360        ParmDecl.getIdentifier() == 0 && ParmDecl.getNumTypeObjects() == 0) {
1361      // Completely missing, emit error.
1362      Diag(DSStart, diag::err_missing_param);
1363    } else {
1364      // Otherwise, we have something.  Add it and let semantic analysis try
1365      // to grok it and add the result to the ParamInfo we are building.
1366
1367      // Inform the actions module about the parameter declarator, so it gets
1368      // added to the current scope.
1369      DeclTy *Param = Actions.ActOnParamDeclarator(CurScope, ParmDecl);
1370
1371      // Parse the default argument, if any. We parse the default
1372      // arguments in all dialects; the semantic analysis in
1373      // ActOnParamDefaultArgument will reject the default argument in
1374      // C.
1375      if (Tok.is(tok::equal)) {
1376        SourceLocation EqualLoc = Tok.getLocation();
1377
1378        // Consume the '='.
1379        ConsumeToken();
1380
1381        // Parse the default argument
1382        ExprResult DefArgResult = ParseAssignmentExpression();
1383        if (DefArgResult.isInvalid) {
1384          SkipUntil(tok::comma, tok::r_paren, true, true);
1385        } else {
1386          // Inform the actions module about the default argument
1387          Actions.ActOnParamDefaultArgument(Param, EqualLoc, DefArgResult.Val);
1388        }
1389      }
1390
1391      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1392                             ParmDecl.getIdentifierLoc(), Param));
1393    }
1394
1395    // If the next token is a comma, consume it and keep reading arguments.
1396    if (Tok.isNot(tok::comma)) break;
1397
1398    // Consume the comma.
1399    ConsumeToken();
1400  }
1401
1402  // Leave prototype scope.
1403  ExitScope();
1404
1405  // Remember that we parsed a function type, and remember the attributes.
1406  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/true, IsVariadic,
1407                                             &ParamInfo[0], ParamInfo.size(),
1408                                             LParenLoc));
1409
1410  // If we have the closing ')', eat it and we're done.
1411  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1412}
1413
1414/// ParseFunctionDeclaratorIdentifierList - While parsing a function declarator
1415/// we found a K&R-style identifier list instead of a type argument list.  The
1416/// current token is known to be the first identifier in the list.
1417///
1418///       identifier-list: [C99 6.7.5]
1419///         identifier
1420///         identifier-list ',' identifier
1421///
1422void Parser::ParseFunctionDeclaratorIdentifierList(SourceLocation LParenLoc,
1423                                                   Declarator &D) {
1424  // Build up an array of information about the parsed arguments.
1425  llvm::SmallVector<DeclaratorChunk::ParamInfo, 16> ParamInfo;
1426  llvm::SmallSet<const IdentifierInfo*, 16> ParamsSoFar;
1427
1428  // If there was no identifier specified for the declarator, either we are in
1429  // an abstract-declarator, or we are in a parameter declarator which was found
1430  // to be abstract.  In abstract-declarators, identifier lists are not valid:
1431  // diagnose this.
1432  if (!D.getIdentifier())
1433    Diag(Tok, diag::ext_ident_list_in_param);
1434
1435  // Tok is known to be the first identifier in the list.  Remember this
1436  // identifier in ParamInfo.
1437  ParamsSoFar.insert(Tok.getIdentifierInfo());
1438  ParamInfo.push_back(DeclaratorChunk::ParamInfo(Tok.getIdentifierInfo(),
1439                                                 Tok.getLocation(), 0));
1440
1441  ConsumeToken();  // eat the first identifier.
1442
1443  while (Tok.is(tok::comma)) {
1444    // Eat the comma.
1445    ConsumeToken();
1446
1447    // If this isn't an identifier, report the error and skip until ')'.
1448    if (Tok.isNot(tok::identifier)) {
1449      Diag(Tok, diag::err_expected_ident);
1450      SkipUntil(tok::r_paren);
1451      return;
1452    }
1453
1454    IdentifierInfo *ParmII = Tok.getIdentifierInfo();
1455
1456    // Reject 'typedef int y; int test(x, y)', but continue parsing.
1457    if (Actions.isTypeName(*ParmII, CurScope))
1458      Diag(Tok, diag::err_unexpected_typedef_ident, ParmII->getName());
1459
1460    // Verify that the argument identifier has not already been mentioned.
1461    if (!ParamsSoFar.insert(ParmII)) {
1462      Diag(Tok.getLocation(), diag::err_param_redefinition, ParmII->getName());
1463    } else {
1464      // Remember this identifier in ParamInfo.
1465      ParamInfo.push_back(DeclaratorChunk::ParamInfo(ParmII,
1466                                                     Tok.getLocation(), 0));
1467    }
1468
1469    // Eat the identifier.
1470    ConsumeToken();
1471  }
1472
1473  // Remember that we parsed a function type, and remember the attributes.  This
1474  // function type is always a K&R style function type, which is not varargs and
1475  // has no prototype.
1476  D.AddTypeInfo(DeclaratorChunk::getFunction(/*proto*/false, /*varargs*/false,
1477                                             &ParamInfo[0], ParamInfo.size(),
1478                                             LParenLoc));
1479
1480  // If we have the closing ')', eat it and we're done.
1481  MatchRHSPunctuation(tok::r_paren, LParenLoc);
1482}
1483
1484/// [C90]   direct-declarator '[' constant-expression[opt] ']'
1485/// [C99]   direct-declarator '[' type-qual-list[opt] assignment-expr[opt] ']'
1486/// [C99]   direct-declarator '[' 'static' type-qual-list[opt] assign-expr ']'
1487/// [C99]   direct-declarator '[' type-qual-list 'static' assignment-expr ']'
1488/// [C99]   direct-declarator '[' type-qual-list[opt] '*' ']'
1489void Parser::ParseBracketDeclarator(Declarator &D) {
1490  SourceLocation StartLoc = ConsumeBracket();
1491
1492  // If valid, this location is the position where we read the 'static' keyword.
1493  SourceLocation StaticLoc;
1494  if (Tok.is(tok::kw_static))
1495    StaticLoc = ConsumeToken();
1496
1497  // If there is a type-qualifier-list, read it now.
1498  DeclSpec DS;
1499  ParseTypeQualifierListOpt(DS);
1500
1501  // If we haven't already read 'static', check to see if there is one after the
1502  // type-qualifier-list.
1503  if (!StaticLoc.isValid() && Tok.is(tok::kw_static))
1504    StaticLoc = ConsumeToken();
1505
1506  // Handle "direct-declarator [ type-qual-list[opt] * ]".
1507  bool isStar = false;
1508  ExprResult NumElements(false);
1509
1510  // Handle the case where we have '[*]' as the array size.  However, a leading
1511  // star could be the start of an expression, for example 'X[*p + 4]'.  Verify
1512  // the the token after the star is a ']'.  Since stars in arrays are
1513  // infrequent, use of lookahead is not costly here.
1514  if (Tok.is(tok::star) && GetLookAheadToken(1).is(tok::r_square)) {
1515    ConsumeToken();  // Eat the '*'.
1516
1517    if (StaticLoc.isValid())
1518      Diag(StaticLoc, diag::err_unspecified_vla_size_with_static);
1519    StaticLoc = SourceLocation();  // Drop the static.
1520    isStar = true;
1521  } else if (Tok.isNot(tok::r_square)) {
1522    // Parse the assignment-expression now.
1523    NumElements = ParseAssignmentExpression();
1524  }
1525
1526  // If there was an error parsing the assignment-expression, recover.
1527  if (NumElements.isInvalid) {
1528    // If the expression was invalid, skip it.
1529    SkipUntil(tok::r_square);
1530    return;
1531  }
1532
1533  MatchRHSPunctuation(tok::r_square, StartLoc);
1534
1535  // If C99 isn't enabled, emit an ext-warn if the arg list wasn't empty and if
1536  // it was not a constant expression.
1537  if (!getLang().C99) {
1538    // TODO: check C90 array constant exprness.
1539    if (isStar || StaticLoc.isValid() ||
1540        0/*TODO: NumElts is not a C90 constantexpr */)
1541      Diag(StartLoc, diag::ext_c99_array_usage);
1542  }
1543
1544  // Remember that we parsed a pointer type, and remember the type-quals.
1545  D.AddTypeInfo(DeclaratorChunk::getArray(DS.getTypeQualifiers(),
1546                                          StaticLoc.isValid(), isStar,
1547                                          NumElements.Val, StartLoc));
1548}
1549
1550/// [GNU]   typeof-specifier:
1551///           typeof ( expressions )
1552///           typeof ( type-name )
1553/// [GNU/C++] typeof unary-expression
1554///
1555void Parser::ParseTypeofSpecifier(DeclSpec &DS) {
1556  assert(Tok.is(tok::kw_typeof) && "Not a typeof specifier");
1557  const IdentifierInfo *BuiltinII = Tok.getIdentifierInfo();
1558  SourceLocation StartLoc = ConsumeToken();
1559
1560  if (Tok.isNot(tok::l_paren)) {
1561    if (!getLang().CPlusPlus) {
1562      Diag(Tok, diag::err_expected_lparen_after, BuiltinII->getName());
1563      return;
1564    }
1565
1566    ExprResult Result = ParseCastExpression(true/*isUnaryExpression*/);
1567    if (Result.isInvalid)
1568      return;
1569
1570    const char *PrevSpec = 0;
1571    // Check for duplicate type specifiers.
1572    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
1573                           Result.Val))
1574      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1575
1576    // FIXME: Not accurate, the range gets one token more than it should.
1577    DS.SetRangeEnd(Tok.getLocation());
1578    return;
1579  }
1580
1581  SourceLocation LParenLoc = ConsumeParen(), RParenLoc;
1582
1583  if (isTypeSpecifierQualifier()) {
1584    TypeTy *Ty = ParseTypeName();
1585
1586    assert(Ty && "Parser::ParseTypeofSpecifier(): missing type");
1587
1588    if (Tok.isNot(tok::r_paren)) {
1589      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1590      return;
1591    }
1592    RParenLoc = ConsumeParen();
1593    const char *PrevSpec = 0;
1594    // Check for duplicate type specifiers (e.g. "int typeof(int)").
1595    if (DS.SetTypeSpecType(DeclSpec::TST_typeofType, StartLoc, PrevSpec, Ty))
1596      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1597  } else { // we have an expression.
1598    ExprResult Result = ParseExpression();
1599
1600    if (Result.isInvalid || Tok.isNot(tok::r_paren)) {
1601      MatchRHSPunctuation(tok::r_paren, LParenLoc);
1602      return;
1603    }
1604    RParenLoc = ConsumeParen();
1605    const char *PrevSpec = 0;
1606    // Check for duplicate type specifiers (e.g. "int typeof(int)").
1607    if (DS.SetTypeSpecType(DeclSpec::TST_typeofExpr, StartLoc, PrevSpec,
1608                           Result.Val))
1609      Diag(StartLoc, diag::err_invalid_decl_spec_combination, PrevSpec);
1610  }
1611  DS.SetRangeEnd(RParenLoc);
1612}
1613
1614
1615