SemaType.cpp revision 63c9a92a805394c1ca9e4a5fd8afb3acbb918d03
1//===--- SemaType.cpp - Semantic Analysis for Types -----------------------===//
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 type-related semantic analysis.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Sema/SemaInternal.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ASTMutationListener.h"
17#include "clang/AST/CXXInheritance.h"
18#include "clang/AST/DeclObjC.h"
19#include "clang/AST/DeclTemplate.h"
20#include "clang/AST/Expr.h"
21#include "clang/AST/TypeLoc.h"
22#include "clang/AST/TypeLocVisitor.h"
23#include "clang/Basic/OpenCL.h"
24#include "clang/Basic/PartialDiagnostic.h"
25#include "clang/Basic/TargetInfo.h"
26#include "clang/Lex/Preprocessor.h"
27#include "clang/Parse/ParseDiagnostic.h"
28#include "clang/Sema/DeclSpec.h"
29#include "clang/Sema/DelayedDiagnostic.h"
30#include "clang/Sema/Lookup.h"
31#include "clang/Sema/ScopeInfo.h"
32#include "clang/Sema/Template.h"
33#include "llvm/ADT/SmallPtrSet.h"
34#include "llvm/ADT/SmallString.h"
35#include "llvm/Support/ErrorHandling.h"
36using namespace clang;
37
38/// isOmittedBlockReturnType - Return true if this declarator is missing a
39/// return type because this is a omitted return type on a block literal.
40static bool isOmittedBlockReturnType(const Declarator &D) {
41  if (D.getContext() != Declarator::BlockLiteralContext ||
42      D.getDeclSpec().hasTypeSpecifier())
43    return false;
44
45  if (D.getNumTypeObjects() == 0)
46    return true;   // ^{ ... }
47
48  if (D.getNumTypeObjects() == 1 &&
49      D.getTypeObject(0).Kind == DeclaratorChunk::Function)
50    return true;   // ^(int X, float Y) { ... }
51
52  return false;
53}
54
55/// diagnoseBadTypeAttribute - Diagnoses a type attribute which
56/// doesn't apply to the given type.
57static void diagnoseBadTypeAttribute(Sema &S, const AttributeList &attr,
58                                     QualType type) {
59  bool useExpansionLoc = false;
60
61  unsigned diagID = 0;
62  switch (attr.getKind()) {
63  case AttributeList::AT_ObjCGC:
64    diagID = diag::warn_pointer_attribute_wrong_type;
65    useExpansionLoc = true;
66    break;
67
68  case AttributeList::AT_ObjCOwnership:
69    diagID = diag::warn_objc_object_attribute_wrong_type;
70    useExpansionLoc = true;
71    break;
72
73  default:
74    // Assume everything else was a function attribute.
75    diagID = diag::warn_function_attribute_wrong_type;
76    break;
77  }
78
79  SourceLocation loc = attr.getLoc();
80  StringRef name = attr.getName()->getName();
81
82  // The GC attributes are usually written with macros;  special-case them.
83  if (useExpansionLoc && loc.isMacroID() && attr.getParameterName()) {
84    if (attr.getParameterName()->isStr("strong")) {
85      if (S.findMacroSpelling(loc, "__strong")) name = "__strong";
86    } else if (attr.getParameterName()->isStr("weak")) {
87      if (S.findMacroSpelling(loc, "__weak")) name = "__weak";
88    }
89  }
90
91  S.Diag(loc, diagID) << name << type;
92}
93
94// objc_gc applies to Objective-C pointers or, otherwise, to the
95// smallest available pointer type (i.e. 'void*' in 'void**').
96#define OBJC_POINTER_TYPE_ATTRS_CASELIST \
97    case AttributeList::AT_ObjCGC: \
98    case AttributeList::AT_ObjCOwnership
99
100// Function type attributes.
101#define FUNCTION_TYPE_ATTRS_CASELIST \
102    case AttributeList::AT_NoReturn: \
103    case AttributeList::AT_CDecl: \
104    case AttributeList::AT_FastCall: \
105    case AttributeList::AT_StdCall: \
106    case AttributeList::AT_ThisCall: \
107    case AttributeList::AT_Pascal: \
108    case AttributeList::AT_Regparm: \
109    case AttributeList::AT_Pcs: \
110    case AttributeList::AT_PnaclCall: \
111    case AttributeList::AT_IntelOclBicc
112
113// Microsoft-specific type qualifiers.
114#define MS_TYPE_ATTRS_CASELIST  \
115    case AttributeList::AT_Ptr32: \
116    case AttributeList::AT_Ptr64: \
117    case AttributeList::AT_SPtr: \
118    case AttributeList::AT_UPtr
119
120namespace {
121  /// An object which stores processing state for the entire
122  /// GetTypeForDeclarator process.
123  class TypeProcessingState {
124    Sema &sema;
125
126    /// The declarator being processed.
127    Declarator &declarator;
128
129    /// The index of the declarator chunk we're currently processing.
130    /// May be the total number of valid chunks, indicating the
131    /// DeclSpec.
132    unsigned chunkIndex;
133
134    /// Whether there are non-trivial modifications to the decl spec.
135    bool trivial;
136
137    /// Whether we saved the attributes in the decl spec.
138    bool hasSavedAttrs;
139
140    /// The original set of attributes on the DeclSpec.
141    SmallVector<AttributeList*, 2> savedAttrs;
142
143    /// A list of attributes to diagnose the uselessness of when the
144    /// processing is complete.
145    SmallVector<AttributeList*, 2> ignoredTypeAttrs;
146
147  public:
148    TypeProcessingState(Sema &sema, Declarator &declarator)
149      : sema(sema), declarator(declarator),
150        chunkIndex(declarator.getNumTypeObjects()),
151        trivial(true), hasSavedAttrs(false) {}
152
153    Sema &getSema() const {
154      return sema;
155    }
156
157    Declarator &getDeclarator() const {
158      return declarator;
159    }
160
161    bool isProcessingDeclSpec() const {
162      return chunkIndex == declarator.getNumTypeObjects();
163    }
164
165    unsigned getCurrentChunkIndex() const {
166      return chunkIndex;
167    }
168
169    void setCurrentChunkIndex(unsigned idx) {
170      assert(idx <= declarator.getNumTypeObjects());
171      chunkIndex = idx;
172    }
173
174    AttributeList *&getCurrentAttrListRef() const {
175      if (isProcessingDeclSpec())
176        return getMutableDeclSpec().getAttributes().getListRef();
177      return declarator.getTypeObject(chunkIndex).getAttrListRef();
178    }
179
180    /// Save the current set of attributes on the DeclSpec.
181    void saveDeclSpecAttrs() {
182      // Don't try to save them multiple times.
183      if (hasSavedAttrs) return;
184
185      DeclSpec &spec = getMutableDeclSpec();
186      for (AttributeList *attr = spec.getAttributes().getList(); attr;
187             attr = attr->getNext())
188        savedAttrs.push_back(attr);
189      trivial &= savedAttrs.empty();
190      hasSavedAttrs = true;
191    }
192
193    /// Record that we had nowhere to put the given type attribute.
194    /// We will diagnose such attributes later.
195    void addIgnoredTypeAttr(AttributeList &attr) {
196      ignoredTypeAttrs.push_back(&attr);
197    }
198
199    /// Diagnose all the ignored type attributes, given that the
200    /// declarator worked out to the given type.
201    void diagnoseIgnoredTypeAttrs(QualType type) const {
202      for (SmallVectorImpl<AttributeList*>::const_iterator
203             i = ignoredTypeAttrs.begin(), e = ignoredTypeAttrs.end();
204           i != e; ++i)
205        diagnoseBadTypeAttribute(getSema(), **i, type);
206    }
207
208    ~TypeProcessingState() {
209      if (trivial) return;
210
211      restoreDeclSpecAttrs();
212    }
213
214  private:
215    DeclSpec &getMutableDeclSpec() const {
216      return const_cast<DeclSpec&>(declarator.getDeclSpec());
217    }
218
219    void restoreDeclSpecAttrs() {
220      assert(hasSavedAttrs);
221
222      if (savedAttrs.empty()) {
223        getMutableDeclSpec().getAttributes().set(0);
224        return;
225      }
226
227      getMutableDeclSpec().getAttributes().set(savedAttrs[0]);
228      for (unsigned i = 0, e = savedAttrs.size() - 1; i != e; ++i)
229        savedAttrs[i]->setNext(savedAttrs[i+1]);
230      savedAttrs.back()->setNext(0);
231    }
232  };
233
234  /// Basically std::pair except that we really want to avoid an
235  /// implicit operator= for safety concerns.  It's also a minor
236  /// link-time optimization for this to be a private type.
237  struct AttrAndList {
238    /// The attribute.
239    AttributeList &first;
240
241    /// The head of the list the attribute is currently in.
242    AttributeList *&second;
243
244    AttrAndList(AttributeList &attr, AttributeList *&head)
245      : first(attr), second(head) {}
246  };
247}
248
249namespace llvm {
250  template <> struct isPodLike<AttrAndList> {
251    static const bool value = true;
252  };
253}
254
255static void spliceAttrIntoList(AttributeList &attr, AttributeList *&head) {
256  attr.setNext(head);
257  head = &attr;
258}
259
260static void spliceAttrOutOfList(AttributeList &attr, AttributeList *&head) {
261  if (head == &attr) {
262    head = attr.getNext();
263    return;
264  }
265
266  AttributeList *cur = head;
267  while (true) {
268    assert(cur && cur->getNext() && "ran out of attrs?");
269    if (cur->getNext() == &attr) {
270      cur->setNext(attr.getNext());
271      return;
272    }
273    cur = cur->getNext();
274  }
275}
276
277static void moveAttrFromListToList(AttributeList &attr,
278                                   AttributeList *&fromList,
279                                   AttributeList *&toList) {
280  spliceAttrOutOfList(attr, fromList);
281  spliceAttrIntoList(attr, toList);
282}
283
284/// The location of a type attribute.
285enum TypeAttrLocation {
286  /// The attribute is in the decl-specifier-seq.
287  TAL_DeclSpec,
288  /// The attribute is part of a DeclaratorChunk.
289  TAL_DeclChunk,
290  /// The attribute is immediately after the declaration's name.
291  TAL_DeclName
292};
293
294static void processTypeAttrs(TypeProcessingState &state,
295                             QualType &type, TypeAttrLocation TAL,
296                             AttributeList *attrs);
297
298static bool handleFunctionTypeAttr(TypeProcessingState &state,
299                                   AttributeList &attr,
300                                   QualType &type);
301
302static bool handleMSPointerTypeQualifierAttr(TypeProcessingState &state,
303                                             AttributeList &attr,
304                                             QualType &type);
305
306static bool handleObjCGCTypeAttr(TypeProcessingState &state,
307                                 AttributeList &attr, QualType &type);
308
309static bool handleObjCOwnershipTypeAttr(TypeProcessingState &state,
310                                       AttributeList &attr, QualType &type);
311
312static bool handleObjCPointerTypeAttr(TypeProcessingState &state,
313                                      AttributeList &attr, QualType &type) {
314  if (attr.getKind() == AttributeList::AT_ObjCGC)
315    return handleObjCGCTypeAttr(state, attr, type);
316  assert(attr.getKind() == AttributeList::AT_ObjCOwnership);
317  return handleObjCOwnershipTypeAttr(state, attr, type);
318}
319
320/// Given the index of a declarator chunk, check whether that chunk
321/// directly specifies the return type of a function and, if so, find
322/// an appropriate place for it.
323///
324/// \param i - a notional index which the search will start
325///   immediately inside
326static DeclaratorChunk *maybeMovePastReturnType(Declarator &declarator,
327                                                unsigned i) {
328  assert(i <= declarator.getNumTypeObjects());
329
330  DeclaratorChunk *result = 0;
331
332  // First, look inwards past parens for a function declarator.
333  for (; i != 0; --i) {
334    DeclaratorChunk &fnChunk = declarator.getTypeObject(i-1);
335    switch (fnChunk.Kind) {
336    case DeclaratorChunk::Paren:
337      continue;
338
339    // If we find anything except a function, bail out.
340    case DeclaratorChunk::Pointer:
341    case DeclaratorChunk::BlockPointer:
342    case DeclaratorChunk::Array:
343    case DeclaratorChunk::Reference:
344    case DeclaratorChunk::MemberPointer:
345      return result;
346
347    // If we do find a function declarator, scan inwards from that,
348    // looking for a block-pointer declarator.
349    case DeclaratorChunk::Function:
350      for (--i; i != 0; --i) {
351        DeclaratorChunk &blockChunk = declarator.getTypeObject(i-1);
352        switch (blockChunk.Kind) {
353        case DeclaratorChunk::Paren:
354        case DeclaratorChunk::Pointer:
355        case DeclaratorChunk::Array:
356        case DeclaratorChunk::Function:
357        case DeclaratorChunk::Reference:
358        case DeclaratorChunk::MemberPointer:
359          continue;
360        case DeclaratorChunk::BlockPointer:
361          result = &blockChunk;
362          goto continue_outer;
363        }
364        llvm_unreachable("bad declarator chunk kind");
365      }
366
367      // If we run out of declarators doing that, we're done.
368      return result;
369    }
370    llvm_unreachable("bad declarator chunk kind");
371
372    // Okay, reconsider from our new point.
373  continue_outer: ;
374  }
375
376  // Ran out of chunks, bail out.
377  return result;
378}
379
380/// Given that an objc_gc attribute was written somewhere on a
381/// declaration *other* than on the declarator itself (for which, use
382/// distributeObjCPointerTypeAttrFromDeclarator), and given that it
383/// didn't apply in whatever position it was written in, try to move
384/// it to a more appropriate position.
385static void distributeObjCPointerTypeAttr(TypeProcessingState &state,
386                                          AttributeList &attr,
387                                          QualType type) {
388  Declarator &declarator = state.getDeclarator();
389
390  // Move it to the outermost normal or block pointer declarator.
391  for (unsigned i = state.getCurrentChunkIndex(); i != 0; --i) {
392    DeclaratorChunk &chunk = declarator.getTypeObject(i-1);
393    switch (chunk.Kind) {
394    case DeclaratorChunk::Pointer:
395    case DeclaratorChunk::BlockPointer: {
396      // But don't move an ARC ownership attribute to the return type
397      // of a block.
398      DeclaratorChunk *destChunk = 0;
399      if (state.isProcessingDeclSpec() &&
400          attr.getKind() == AttributeList::AT_ObjCOwnership)
401        destChunk = maybeMovePastReturnType(declarator, i - 1);
402      if (!destChunk) destChunk = &chunk;
403
404      moveAttrFromListToList(attr, state.getCurrentAttrListRef(),
405                             destChunk->getAttrListRef());
406      return;
407    }
408
409    case DeclaratorChunk::Paren:
410    case DeclaratorChunk::Array:
411      continue;
412
413    // We may be starting at the return type of a block.
414    case DeclaratorChunk::Function:
415      if (state.isProcessingDeclSpec() &&
416          attr.getKind() == AttributeList::AT_ObjCOwnership) {
417        if (DeclaratorChunk *dest = maybeMovePastReturnType(declarator, i)) {
418          moveAttrFromListToList(attr, state.getCurrentAttrListRef(),
419                                 dest->getAttrListRef());
420          return;
421        }
422      }
423      goto error;
424
425    // Don't walk through these.
426    case DeclaratorChunk::Reference:
427    case DeclaratorChunk::MemberPointer:
428      goto error;
429    }
430  }
431 error:
432
433  diagnoseBadTypeAttribute(state.getSema(), attr, type);
434}
435
436/// Distribute an objc_gc type attribute that was written on the
437/// declarator.
438static void
439distributeObjCPointerTypeAttrFromDeclarator(TypeProcessingState &state,
440                                            AttributeList &attr,
441                                            QualType &declSpecType) {
442  Declarator &declarator = state.getDeclarator();
443
444  // objc_gc goes on the innermost pointer to something that's not a
445  // pointer.
446  unsigned innermost = -1U;
447  bool considerDeclSpec = true;
448  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
449    DeclaratorChunk &chunk = declarator.getTypeObject(i);
450    switch (chunk.Kind) {
451    case DeclaratorChunk::Pointer:
452    case DeclaratorChunk::BlockPointer:
453      innermost = i;
454      continue;
455
456    case DeclaratorChunk::Reference:
457    case DeclaratorChunk::MemberPointer:
458    case DeclaratorChunk::Paren:
459    case DeclaratorChunk::Array:
460      continue;
461
462    case DeclaratorChunk::Function:
463      considerDeclSpec = false;
464      goto done;
465    }
466  }
467 done:
468
469  // That might actually be the decl spec if we weren't blocked by
470  // anything in the declarator.
471  if (considerDeclSpec) {
472    if (handleObjCPointerTypeAttr(state, attr, declSpecType)) {
473      // Splice the attribute into the decl spec.  Prevents the
474      // attribute from being applied multiple times and gives
475      // the source-location-filler something to work with.
476      state.saveDeclSpecAttrs();
477      moveAttrFromListToList(attr, declarator.getAttrListRef(),
478               declarator.getMutableDeclSpec().getAttributes().getListRef());
479      return;
480    }
481  }
482
483  // Otherwise, if we found an appropriate chunk, splice the attribute
484  // into it.
485  if (innermost != -1U) {
486    moveAttrFromListToList(attr, declarator.getAttrListRef(),
487                       declarator.getTypeObject(innermost).getAttrListRef());
488    return;
489  }
490
491  // Otherwise, diagnose when we're done building the type.
492  spliceAttrOutOfList(attr, declarator.getAttrListRef());
493  state.addIgnoredTypeAttr(attr);
494}
495
496/// A function type attribute was written somewhere in a declaration
497/// *other* than on the declarator itself or in the decl spec.  Given
498/// that it didn't apply in whatever position it was written in, try
499/// to move it to a more appropriate position.
500static void distributeFunctionTypeAttr(TypeProcessingState &state,
501                                       AttributeList &attr,
502                                       QualType type) {
503  Declarator &declarator = state.getDeclarator();
504
505  // Try to push the attribute from the return type of a function to
506  // the function itself.
507  for (unsigned i = state.getCurrentChunkIndex(); i != 0; --i) {
508    DeclaratorChunk &chunk = declarator.getTypeObject(i-1);
509    switch (chunk.Kind) {
510    case DeclaratorChunk::Function:
511      moveAttrFromListToList(attr, state.getCurrentAttrListRef(),
512                             chunk.getAttrListRef());
513      return;
514
515    case DeclaratorChunk::Paren:
516    case DeclaratorChunk::Pointer:
517    case DeclaratorChunk::BlockPointer:
518    case DeclaratorChunk::Array:
519    case DeclaratorChunk::Reference:
520    case DeclaratorChunk::MemberPointer:
521      continue;
522    }
523  }
524
525  diagnoseBadTypeAttribute(state.getSema(), attr, type);
526}
527
528/// Try to distribute a function type attribute to the innermost
529/// function chunk or type.  Returns true if the attribute was
530/// distributed, false if no location was found.
531static bool
532distributeFunctionTypeAttrToInnermost(TypeProcessingState &state,
533                                      AttributeList &attr,
534                                      AttributeList *&attrList,
535                                      QualType &declSpecType) {
536  Declarator &declarator = state.getDeclarator();
537
538  // Put it on the innermost function chunk, if there is one.
539  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
540    DeclaratorChunk &chunk = declarator.getTypeObject(i);
541    if (chunk.Kind != DeclaratorChunk::Function) continue;
542
543    moveAttrFromListToList(attr, attrList, chunk.getAttrListRef());
544    return true;
545  }
546
547  if (handleFunctionTypeAttr(state, attr, declSpecType)) {
548    spliceAttrOutOfList(attr, attrList);
549    return true;
550  }
551
552  return false;
553}
554
555/// A function type attribute was written in the decl spec.  Try to
556/// apply it somewhere.
557static void
558distributeFunctionTypeAttrFromDeclSpec(TypeProcessingState &state,
559                                       AttributeList &attr,
560                                       QualType &declSpecType) {
561  state.saveDeclSpecAttrs();
562
563  // C++11 attributes before the decl specifiers actually appertain to
564  // the declarators. Move them straight there. We don't support the
565  // 'put them wherever you like' semantics we allow for GNU attributes.
566  if (attr.isCXX11Attribute()) {
567    moveAttrFromListToList(attr, state.getCurrentAttrListRef(),
568                           state.getDeclarator().getAttrListRef());
569    return;
570  }
571
572  // Try to distribute to the innermost.
573  if (distributeFunctionTypeAttrToInnermost(state, attr,
574                                            state.getCurrentAttrListRef(),
575                                            declSpecType))
576    return;
577
578  // If that failed, diagnose the bad attribute when the declarator is
579  // fully built.
580  state.addIgnoredTypeAttr(attr);
581}
582
583/// A function type attribute was written on the declarator.  Try to
584/// apply it somewhere.
585static void
586distributeFunctionTypeAttrFromDeclarator(TypeProcessingState &state,
587                                         AttributeList &attr,
588                                         QualType &declSpecType) {
589  Declarator &declarator = state.getDeclarator();
590
591  // Try to distribute to the innermost.
592  if (distributeFunctionTypeAttrToInnermost(state, attr,
593                                            declarator.getAttrListRef(),
594                                            declSpecType))
595    return;
596
597  // If that failed, diagnose the bad attribute when the declarator is
598  // fully built.
599  spliceAttrOutOfList(attr, declarator.getAttrListRef());
600  state.addIgnoredTypeAttr(attr);
601}
602
603/// \brief Given that there are attributes written on the declarator
604/// itself, try to distribute any type attributes to the appropriate
605/// declarator chunk.
606///
607/// These are attributes like the following:
608///   int f ATTR;
609///   int (f ATTR)();
610/// but not necessarily this:
611///   int f() ATTR;
612static void distributeTypeAttrsFromDeclarator(TypeProcessingState &state,
613                                              QualType &declSpecType) {
614  // Collect all the type attributes from the declarator itself.
615  assert(state.getDeclarator().getAttributes() && "declarator has no attrs!");
616  AttributeList *attr = state.getDeclarator().getAttributes();
617  AttributeList *next;
618  do {
619    next = attr->getNext();
620
621    // Do not distribute C++11 attributes. They have strict rules for what
622    // they appertain to.
623    if (attr->isCXX11Attribute())
624      continue;
625
626    switch (attr->getKind()) {
627    OBJC_POINTER_TYPE_ATTRS_CASELIST:
628      distributeObjCPointerTypeAttrFromDeclarator(state, *attr, declSpecType);
629      break;
630
631    case AttributeList::AT_NSReturnsRetained:
632      if (!state.getSema().getLangOpts().ObjCAutoRefCount)
633        break;
634      // fallthrough
635
636    FUNCTION_TYPE_ATTRS_CASELIST:
637      distributeFunctionTypeAttrFromDeclarator(state, *attr, declSpecType);
638      break;
639
640    MS_TYPE_ATTRS_CASELIST:
641      // Microsoft type attributes cannot go after the declarator-id.
642      continue;
643
644    default:
645      break;
646    }
647  } while ((attr = next));
648}
649
650/// Add a synthetic '()' to a block-literal declarator if it is
651/// required, given the return type.
652static void maybeSynthesizeBlockSignature(TypeProcessingState &state,
653                                          QualType declSpecType) {
654  Declarator &declarator = state.getDeclarator();
655
656  // First, check whether the declarator would produce a function,
657  // i.e. whether the innermost semantic chunk is a function.
658  if (declarator.isFunctionDeclarator()) {
659    // If so, make that declarator a prototyped declarator.
660    declarator.getFunctionTypeInfo().hasPrototype = true;
661    return;
662  }
663
664  // If there are any type objects, the type as written won't name a
665  // function, regardless of the decl spec type.  This is because a
666  // block signature declarator is always an abstract-declarator, and
667  // abstract-declarators can't just be parentheses chunks.  Therefore
668  // we need to build a function chunk unless there are no type
669  // objects and the decl spec type is a function.
670  if (!declarator.getNumTypeObjects() && declSpecType->isFunctionType())
671    return;
672
673  // Note that there *are* cases with invalid declarators where
674  // declarators consist solely of parentheses.  In general, these
675  // occur only in failed efforts to make function declarators, so
676  // faking up the function chunk is still the right thing to do.
677
678  // Otherwise, we need to fake up a function declarator.
679  SourceLocation loc = declarator.getLocStart();
680
681  // ...and *prepend* it to the declarator.
682  SourceLocation NoLoc;
683  declarator.AddInnermostTypeInfo(DeclaratorChunk::getFunction(
684                             /*HasProto=*/true,
685                             /*IsAmbiguous=*/false,
686                             /*LParenLoc=*/NoLoc,
687                             /*ArgInfo=*/0,
688                             /*NumArgs=*/0,
689                             /*EllipsisLoc=*/NoLoc,
690                             /*RParenLoc=*/NoLoc,
691                             /*TypeQuals=*/0,
692                             /*RefQualifierIsLvalueRef=*/true,
693                             /*RefQualifierLoc=*/NoLoc,
694                             /*ConstQualifierLoc=*/NoLoc,
695                             /*VolatileQualifierLoc=*/NoLoc,
696                             /*MutableLoc=*/NoLoc,
697                             EST_None,
698                             /*ESpecLoc=*/NoLoc,
699                             /*Exceptions=*/0,
700                             /*ExceptionRanges=*/0,
701                             /*NumExceptions=*/0,
702                             /*NoexceptExpr=*/0,
703                             loc, loc, declarator));
704
705  // For consistency, make sure the state still has us as processing
706  // the decl spec.
707  assert(state.getCurrentChunkIndex() == declarator.getNumTypeObjects() - 1);
708  state.setCurrentChunkIndex(declarator.getNumTypeObjects());
709}
710
711/// \brief Convert the specified declspec to the appropriate type
712/// object.
713/// \param state Specifies the declarator containing the declaration specifier
714/// to be converted, along with other associated processing state.
715/// \returns The type described by the declaration specifiers.  This function
716/// never returns null.
717static QualType ConvertDeclSpecToType(TypeProcessingState &state) {
718  // FIXME: Should move the logic from DeclSpec::Finish to here for validity
719  // checking.
720
721  Sema &S = state.getSema();
722  Declarator &declarator = state.getDeclarator();
723  const DeclSpec &DS = declarator.getDeclSpec();
724  SourceLocation DeclLoc = declarator.getIdentifierLoc();
725  if (DeclLoc.isInvalid())
726    DeclLoc = DS.getLocStart();
727
728  ASTContext &Context = S.Context;
729
730  QualType Result;
731  switch (DS.getTypeSpecType()) {
732  case DeclSpec::TST_void:
733    Result = Context.VoidTy;
734    break;
735  case DeclSpec::TST_char:
736    if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified)
737      Result = Context.CharTy;
738    else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed)
739      Result = Context.SignedCharTy;
740    else {
741      assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned &&
742             "Unknown TSS value");
743      Result = Context.UnsignedCharTy;
744    }
745    break;
746  case DeclSpec::TST_wchar:
747    if (DS.getTypeSpecSign() == DeclSpec::TSS_unspecified)
748      Result = Context.WCharTy;
749    else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) {
750      S.Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec)
751        << DS.getSpecifierName(DS.getTypeSpecType());
752      Result = Context.getSignedWCharType();
753    } else {
754      assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned &&
755        "Unknown TSS value");
756      S.Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec)
757        << DS.getSpecifierName(DS.getTypeSpecType());
758      Result = Context.getUnsignedWCharType();
759    }
760    break;
761  case DeclSpec::TST_char16:
762      assert(DS.getTypeSpecSign() == DeclSpec::TSS_unspecified &&
763        "Unknown TSS value");
764      Result = Context.Char16Ty;
765    break;
766  case DeclSpec::TST_char32:
767      assert(DS.getTypeSpecSign() == DeclSpec::TSS_unspecified &&
768        "Unknown TSS value");
769      Result = Context.Char32Ty;
770    break;
771  case DeclSpec::TST_unspecified:
772    // "<proto1,proto2>" is an objc qualified ID with a missing id.
773    if (DeclSpec::ProtocolQualifierListTy PQ = DS.getProtocolQualifiers()) {
774      Result = Context.getObjCObjectType(Context.ObjCBuiltinIdTy,
775                                         (ObjCProtocolDecl*const*)PQ,
776                                         DS.getNumProtocolQualifiers());
777      Result = Context.getObjCObjectPointerType(Result);
778      break;
779    }
780
781    // If this is a missing declspec in a block literal return context, then it
782    // is inferred from the return statements inside the block.
783    // The declspec is always missing in a lambda expr context; it is either
784    // specified with a trailing return type or inferred.
785    if (declarator.getContext() == Declarator::LambdaExprContext ||
786        isOmittedBlockReturnType(declarator)) {
787      Result = Context.DependentTy;
788      break;
789    }
790
791    // Unspecified typespec defaults to int in C90.  However, the C90 grammar
792    // [C90 6.5] only allows a decl-spec if there was *some* type-specifier,
793    // type-qualifier, or storage-class-specifier.  If not, emit an extwarn.
794    // Note that the one exception to this is function definitions, which are
795    // allowed to be completely missing a declspec.  This is handled in the
796    // parser already though by it pretending to have seen an 'int' in this
797    // case.
798    if (S.getLangOpts().ImplicitInt) {
799      // In C89 mode, we only warn if there is a completely missing declspec
800      // when one is not allowed.
801      if (DS.isEmpty()) {
802        S.Diag(DeclLoc, diag::ext_missing_declspec)
803          << DS.getSourceRange()
804        << FixItHint::CreateInsertion(DS.getLocStart(), "int");
805      }
806    } else if (!DS.hasTypeSpecifier()) {
807      // C99 and C++ require a type specifier.  For example, C99 6.7.2p2 says:
808      // "At least one type specifier shall be given in the declaration
809      // specifiers in each declaration, and in the specifier-qualifier list in
810      // each struct declaration and type name."
811      if (S.getLangOpts().CPlusPlus) {
812        S.Diag(DeclLoc, diag::err_missing_type_specifier)
813          << DS.getSourceRange();
814
815        // When this occurs in C++ code, often something is very broken with the
816        // value being declared, poison it as invalid so we don't get chains of
817        // errors.
818        declarator.setInvalidType(true);
819      } else {
820        S.Diag(DeclLoc, diag::ext_missing_type_specifier)
821          << DS.getSourceRange();
822      }
823    }
824
825    // FALL THROUGH.
826  case DeclSpec::TST_int: {
827    if (DS.getTypeSpecSign() != DeclSpec::TSS_unsigned) {
828      switch (DS.getTypeSpecWidth()) {
829      case DeclSpec::TSW_unspecified: Result = Context.IntTy; break;
830      case DeclSpec::TSW_short:       Result = Context.ShortTy; break;
831      case DeclSpec::TSW_long:        Result = Context.LongTy; break;
832      case DeclSpec::TSW_longlong:
833        Result = Context.LongLongTy;
834
835        // 'long long' is a C99 or C++11 feature.
836        if (!S.getLangOpts().C99) {
837          if (S.getLangOpts().CPlusPlus)
838            S.Diag(DS.getTypeSpecWidthLoc(),
839                   S.getLangOpts().CPlusPlus11 ?
840                   diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
841          else
842            S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
843        }
844        break;
845      }
846    } else {
847      switch (DS.getTypeSpecWidth()) {
848      case DeclSpec::TSW_unspecified: Result = Context.UnsignedIntTy; break;
849      case DeclSpec::TSW_short:       Result = Context.UnsignedShortTy; break;
850      case DeclSpec::TSW_long:        Result = Context.UnsignedLongTy; break;
851      case DeclSpec::TSW_longlong:
852        Result = Context.UnsignedLongLongTy;
853
854        // 'long long' is a C99 or C++11 feature.
855        if (!S.getLangOpts().C99) {
856          if (S.getLangOpts().CPlusPlus)
857            S.Diag(DS.getTypeSpecWidthLoc(),
858                   S.getLangOpts().CPlusPlus11 ?
859                   diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
860          else
861            S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
862        }
863        break;
864      }
865    }
866    break;
867  }
868  case DeclSpec::TST_int128:
869    if (!S.PP.getTargetInfo().hasInt128Type())
870      S.Diag(DS.getTypeSpecTypeLoc(), diag::err_int128_unsupported);
871    if (DS.getTypeSpecSign() == DeclSpec::TSS_unsigned)
872      Result = Context.UnsignedInt128Ty;
873    else
874      Result = Context.Int128Ty;
875    break;
876  case DeclSpec::TST_half: Result = Context.HalfTy; break;
877  case DeclSpec::TST_float: Result = Context.FloatTy; break;
878  case DeclSpec::TST_double:
879    if (DS.getTypeSpecWidth() == DeclSpec::TSW_long)
880      Result = Context.LongDoubleTy;
881    else
882      Result = Context.DoubleTy;
883
884    if (S.getLangOpts().OpenCL && !S.getOpenCLOptions().cl_khr_fp64) {
885      S.Diag(DS.getTypeSpecTypeLoc(), diag::err_double_requires_fp64);
886      declarator.setInvalidType(true);
887    }
888    break;
889  case DeclSpec::TST_bool: Result = Context.BoolTy; break; // _Bool or bool
890  case DeclSpec::TST_decimal32:    // _Decimal32
891  case DeclSpec::TST_decimal64:    // _Decimal64
892  case DeclSpec::TST_decimal128:   // _Decimal128
893    S.Diag(DS.getTypeSpecTypeLoc(), diag::err_decimal_unsupported);
894    Result = Context.IntTy;
895    declarator.setInvalidType(true);
896    break;
897  case DeclSpec::TST_class:
898  case DeclSpec::TST_enum:
899  case DeclSpec::TST_union:
900  case DeclSpec::TST_struct:
901  case DeclSpec::TST_interface: {
902    TypeDecl *D = dyn_cast_or_null<TypeDecl>(DS.getRepAsDecl());
903    if (!D) {
904      // This can happen in C++ with ambiguous lookups.
905      Result = Context.IntTy;
906      declarator.setInvalidType(true);
907      break;
908    }
909
910    // If the type is deprecated or unavailable, diagnose it.
911    S.DiagnoseUseOfDecl(D, DS.getTypeSpecTypeNameLoc());
912
913    assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 &&
914           DS.getTypeSpecSign() == 0 && "No qualifiers on tag names!");
915
916    // TypeQuals handled by caller.
917    Result = Context.getTypeDeclType(D);
918
919    // In both C and C++, make an ElaboratedType.
920    ElaboratedTypeKeyword Keyword
921      = ElaboratedType::getKeywordForTypeSpec(DS.getTypeSpecType());
922    Result = S.getElaboratedType(Keyword, DS.getTypeSpecScope(), Result);
923    break;
924  }
925  case DeclSpec::TST_typename: {
926    assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 &&
927           DS.getTypeSpecSign() == 0 &&
928           "Can't handle qualifiers on typedef names yet!");
929    Result = S.GetTypeFromParser(DS.getRepAsType());
930    if (Result.isNull())
931      declarator.setInvalidType(true);
932    else if (DeclSpec::ProtocolQualifierListTy PQ
933               = DS.getProtocolQualifiers()) {
934      if (const ObjCObjectType *ObjT = Result->getAs<ObjCObjectType>()) {
935        // Silently drop any existing protocol qualifiers.
936        // TODO: determine whether that's the right thing to do.
937        if (ObjT->getNumProtocols())
938          Result = ObjT->getBaseType();
939
940        if (DS.getNumProtocolQualifiers())
941          Result = Context.getObjCObjectType(Result,
942                                             (ObjCProtocolDecl*const*) PQ,
943                                             DS.getNumProtocolQualifiers());
944      } else if (Result->isObjCIdType()) {
945        // id<protocol-list>
946        Result = Context.getObjCObjectType(Context.ObjCBuiltinIdTy,
947                                           (ObjCProtocolDecl*const*) PQ,
948                                           DS.getNumProtocolQualifiers());
949        Result = Context.getObjCObjectPointerType(Result);
950      } else if (Result->isObjCClassType()) {
951        // Class<protocol-list>
952        Result = Context.getObjCObjectType(Context.ObjCBuiltinClassTy,
953                                           (ObjCProtocolDecl*const*) PQ,
954                                           DS.getNumProtocolQualifiers());
955        Result = Context.getObjCObjectPointerType(Result);
956      } else {
957        S.Diag(DeclLoc, diag::err_invalid_protocol_qualifiers)
958          << DS.getSourceRange();
959        declarator.setInvalidType(true);
960      }
961    }
962
963    // TypeQuals handled by caller.
964    break;
965  }
966  case DeclSpec::TST_typeofType:
967    // FIXME: Preserve type source info.
968    Result = S.GetTypeFromParser(DS.getRepAsType());
969    assert(!Result.isNull() && "Didn't get a type for typeof?");
970    if (!Result->isDependentType())
971      if (const TagType *TT = Result->getAs<TagType>())
972        S.DiagnoseUseOfDecl(TT->getDecl(), DS.getTypeSpecTypeLoc());
973    // TypeQuals handled by caller.
974    Result = Context.getTypeOfType(Result);
975    break;
976  case DeclSpec::TST_typeofExpr: {
977    Expr *E = DS.getRepAsExpr();
978    assert(E && "Didn't get an expression for typeof?");
979    // TypeQuals handled by caller.
980    Result = S.BuildTypeofExprType(E, DS.getTypeSpecTypeLoc());
981    if (Result.isNull()) {
982      Result = Context.IntTy;
983      declarator.setInvalidType(true);
984    }
985    break;
986  }
987  case DeclSpec::TST_decltype: {
988    Expr *E = DS.getRepAsExpr();
989    assert(E && "Didn't get an expression for decltype?");
990    // TypeQuals handled by caller.
991    Result = S.BuildDecltypeType(E, DS.getTypeSpecTypeLoc());
992    if (Result.isNull()) {
993      Result = Context.IntTy;
994      declarator.setInvalidType(true);
995    }
996    break;
997  }
998  case DeclSpec::TST_underlyingType:
999    Result = S.GetTypeFromParser(DS.getRepAsType());
1000    assert(!Result.isNull() && "Didn't get a type for __underlying_type?");
1001    Result = S.BuildUnaryTransformType(Result,
1002                                       UnaryTransformType::EnumUnderlyingType,
1003                                       DS.getTypeSpecTypeLoc());
1004    if (Result.isNull()) {
1005      Result = Context.IntTy;
1006      declarator.setInvalidType(true);
1007    }
1008    break;
1009
1010  case DeclSpec::TST_auto:
1011    // TypeQuals handled by caller.
1012    Result = Context.getAutoType(QualType(), /*decltype(auto)*/false);
1013    break;
1014
1015  case DeclSpec::TST_decltype_auto:
1016    Result = Context.getAutoType(QualType(), /*decltype(auto)*/true);
1017    break;
1018
1019  case DeclSpec::TST_unknown_anytype:
1020    Result = Context.UnknownAnyTy;
1021    break;
1022
1023  case DeclSpec::TST_atomic:
1024    Result = S.GetTypeFromParser(DS.getRepAsType());
1025    assert(!Result.isNull() && "Didn't get a type for _Atomic?");
1026    Result = S.BuildAtomicType(Result, DS.getTypeSpecTypeLoc());
1027    if (Result.isNull()) {
1028      Result = Context.IntTy;
1029      declarator.setInvalidType(true);
1030    }
1031    break;
1032
1033  case DeclSpec::TST_image1d_t:
1034    Result = Context.OCLImage1dTy;
1035    break;
1036
1037  case DeclSpec::TST_image1d_array_t:
1038    Result = Context.OCLImage1dArrayTy;
1039    break;
1040
1041  case DeclSpec::TST_image1d_buffer_t:
1042    Result = Context.OCLImage1dBufferTy;
1043    break;
1044
1045  case DeclSpec::TST_image2d_t:
1046    Result = Context.OCLImage2dTy;
1047    break;
1048
1049  case DeclSpec::TST_image2d_array_t:
1050    Result = Context.OCLImage2dArrayTy;
1051    break;
1052
1053  case DeclSpec::TST_image3d_t:
1054    Result = Context.OCLImage3dTy;
1055    break;
1056
1057  case DeclSpec::TST_sampler_t:
1058    Result = Context.OCLSamplerTy;
1059    break;
1060
1061  case DeclSpec::TST_event_t:
1062    Result = Context.OCLEventTy;
1063    break;
1064
1065  case DeclSpec::TST_error:
1066    Result = Context.IntTy;
1067    declarator.setInvalidType(true);
1068    break;
1069  }
1070
1071  // Handle complex types.
1072  if (DS.getTypeSpecComplex() == DeclSpec::TSC_complex) {
1073    if (S.getLangOpts().Freestanding)
1074      S.Diag(DS.getTypeSpecComplexLoc(), diag::ext_freestanding_complex);
1075    Result = Context.getComplexType(Result);
1076  } else if (DS.isTypeAltiVecVector()) {
1077    unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(Result));
1078    assert(typeSize > 0 && "type size for vector must be greater than 0 bits");
1079    VectorType::VectorKind VecKind = VectorType::AltiVecVector;
1080    if (DS.isTypeAltiVecPixel())
1081      VecKind = VectorType::AltiVecPixel;
1082    else if (DS.isTypeAltiVecBool())
1083      VecKind = VectorType::AltiVecBool;
1084    Result = Context.getVectorType(Result, 128/typeSize, VecKind);
1085  }
1086
1087  // FIXME: Imaginary.
1088  if (DS.getTypeSpecComplex() == DeclSpec::TSC_imaginary)
1089    S.Diag(DS.getTypeSpecComplexLoc(), diag::err_imaginary_not_supported);
1090
1091  // Before we process any type attributes, synthesize a block literal
1092  // function declarator if necessary.
1093  if (declarator.getContext() == Declarator::BlockLiteralContext)
1094    maybeSynthesizeBlockSignature(state, Result);
1095
1096  // Apply any type attributes from the decl spec.  This may cause the
1097  // list of type attributes to be temporarily saved while the type
1098  // attributes are pushed around.
1099  if (AttributeList *attrs = DS.getAttributes().getList())
1100    processTypeAttrs(state, Result, TAL_DeclSpec, attrs);
1101
1102  // Apply const/volatile/restrict qualifiers to T.
1103  if (unsigned TypeQuals = DS.getTypeQualifiers()) {
1104
1105    // Warn about CV qualifiers on functions: C99 6.7.3p8: "If the specification
1106    // of a function type includes any type qualifiers, the behavior is
1107    // undefined."
1108    if (Result->isFunctionType() && TypeQuals) {
1109      if (TypeQuals & DeclSpec::TQ_const)
1110        S.Diag(DS.getConstSpecLoc(), diag::warn_typecheck_function_qualifiers)
1111          << Result << DS.getSourceRange();
1112      else if (TypeQuals & DeclSpec::TQ_volatile)
1113        S.Diag(DS.getVolatileSpecLoc(), diag::warn_typecheck_function_qualifiers)
1114          << Result << DS.getSourceRange();
1115      else {
1116        assert((TypeQuals & (DeclSpec::TQ_restrict | DeclSpec::TQ_atomic)) &&
1117               "Has CVRA quals but not C, V, R, or A?");
1118        // No diagnostic; we'll diagnose 'restrict' or '_Atomic' applied to a
1119        // function type later, in BuildQualifiedType.
1120      }
1121    }
1122
1123    // C++ [dcl.ref]p1:
1124    //   Cv-qualified references are ill-formed except when the
1125    //   cv-qualifiers are introduced through the use of a typedef
1126    //   (7.1.3) or of a template type argument (14.3), in which
1127    //   case the cv-qualifiers are ignored.
1128    // FIXME: Shouldn't we be checking SCS_typedef here?
1129    if (DS.getTypeSpecType() == DeclSpec::TST_typename &&
1130        TypeQuals && Result->isReferenceType()) {
1131      TypeQuals &= ~DeclSpec::TQ_const;
1132      TypeQuals &= ~DeclSpec::TQ_volatile;
1133      TypeQuals &= ~DeclSpec::TQ_atomic;
1134    }
1135
1136    // C90 6.5.3 constraints: "The same type qualifier shall not appear more
1137    // than once in the same specifier-list or qualifier-list, either directly
1138    // or via one or more typedefs."
1139    if (!S.getLangOpts().C99 && !S.getLangOpts().CPlusPlus
1140        && TypeQuals & Result.getCVRQualifiers()) {
1141      if (TypeQuals & DeclSpec::TQ_const && Result.isConstQualified()) {
1142        S.Diag(DS.getConstSpecLoc(), diag::ext_duplicate_declspec)
1143          << "const";
1144      }
1145
1146      if (TypeQuals & DeclSpec::TQ_volatile && Result.isVolatileQualified()) {
1147        S.Diag(DS.getVolatileSpecLoc(), diag::ext_duplicate_declspec)
1148          << "volatile";
1149      }
1150
1151      // C90 doesn't have restrict nor _Atomic, so it doesn't force us to
1152      // produce a warning in this case.
1153    }
1154
1155    QualType Qualified = S.BuildQualifiedType(Result, DeclLoc, TypeQuals, &DS);
1156
1157    // If adding qualifiers fails, just use the unqualified type.
1158    if (Qualified.isNull())
1159      declarator.setInvalidType(true);
1160    else
1161      Result = Qualified;
1162  }
1163
1164  return Result;
1165}
1166
1167static std::string getPrintableNameForEntity(DeclarationName Entity) {
1168  if (Entity)
1169    return Entity.getAsString();
1170
1171  return "type name";
1172}
1173
1174QualType Sema::BuildQualifiedType(QualType T, SourceLocation Loc,
1175                                  Qualifiers Qs, const DeclSpec *DS) {
1176  // Enforce C99 6.7.3p2: "Types other than pointer types derived from
1177  // object or incomplete types shall not be restrict-qualified."
1178  if (Qs.hasRestrict()) {
1179    unsigned DiagID = 0;
1180    QualType ProblemTy;
1181
1182    if (T->isAnyPointerType() || T->isReferenceType() ||
1183        T->isMemberPointerType()) {
1184      QualType EltTy;
1185      if (T->isObjCObjectPointerType())
1186        EltTy = T;
1187      else if (const MemberPointerType *PTy = T->getAs<MemberPointerType>())
1188        EltTy = PTy->getPointeeType();
1189      else
1190        EltTy = T->getPointeeType();
1191
1192      // If we have a pointer or reference, the pointee must have an object
1193      // incomplete type.
1194      if (!EltTy->isIncompleteOrObjectType()) {
1195        DiagID = diag::err_typecheck_invalid_restrict_invalid_pointee;
1196        ProblemTy = EltTy;
1197      }
1198    } else if (!T->isDependentType()) {
1199      DiagID = diag::err_typecheck_invalid_restrict_not_pointer;
1200      ProblemTy = T;
1201    }
1202
1203    if (DiagID) {
1204      Diag(DS ? DS->getRestrictSpecLoc() : Loc, DiagID) << ProblemTy;
1205      Qs.removeRestrict();
1206    }
1207  }
1208
1209  return Context.getQualifiedType(T, Qs);
1210}
1211
1212QualType Sema::BuildQualifiedType(QualType T, SourceLocation Loc,
1213                                  unsigned CVRA, const DeclSpec *DS) {
1214  // Convert from DeclSpec::TQ to Qualifiers::TQ by just dropping TQ_atomic.
1215  unsigned CVR = CVRA & ~DeclSpec::TQ_atomic;
1216
1217  // C11 6.7.3/5:
1218  //   If the same qualifier appears more than once in the same
1219  //   specifier-qualifier-list, either directly or via one or more typedefs,
1220  //   the behavior is the same as if it appeared only once.
1221  //
1222  // It's not specified what happens when the _Atomic qualifier is applied to
1223  // a type specified with the _Atomic specifier, but we assume that this
1224  // should be treated as if the _Atomic qualifier appeared multiple times.
1225  if (CVRA & DeclSpec::TQ_atomic && !T->isAtomicType()) {
1226    // C11 6.7.3/5:
1227    //   If other qualifiers appear along with the _Atomic qualifier in a
1228    //   specifier-qualifier-list, the resulting type is the so-qualified
1229    //   atomic type.
1230    //
1231    // Don't need to worry about array types here, since _Atomic can't be
1232    // applied to such types.
1233    SplitQualType Split = T.getSplitUnqualifiedType();
1234    T = BuildAtomicType(QualType(Split.Ty, 0),
1235                        DS ? DS->getAtomicSpecLoc() : Loc);
1236    if (T.isNull())
1237      return T;
1238    Split.Quals.addCVRQualifiers(CVR);
1239    return BuildQualifiedType(T, Loc, Split.Quals);
1240  }
1241
1242  return BuildQualifiedType(T, Loc, Qualifiers::fromCVRMask(CVR), DS);
1243}
1244
1245/// \brief Build a paren type including \p T.
1246QualType Sema::BuildParenType(QualType T) {
1247  return Context.getParenType(T);
1248}
1249
1250/// Given that we're building a pointer or reference to the given
1251static QualType inferARCLifetimeForPointee(Sema &S, QualType type,
1252                                           SourceLocation loc,
1253                                           bool isReference) {
1254  // Bail out if retention is unrequired or already specified.
1255  if (!type->isObjCLifetimeType() ||
1256      type.getObjCLifetime() != Qualifiers::OCL_None)
1257    return type;
1258
1259  Qualifiers::ObjCLifetime implicitLifetime = Qualifiers::OCL_None;
1260
1261  // If the object type is const-qualified, we can safely use
1262  // __unsafe_unretained.  This is safe (because there are no read
1263  // barriers), and it'll be safe to coerce anything but __weak* to
1264  // the resulting type.
1265  if (type.isConstQualified()) {
1266    implicitLifetime = Qualifiers::OCL_ExplicitNone;
1267
1268  // Otherwise, check whether the static type does not require
1269  // retaining.  This currently only triggers for Class (possibly
1270  // protocol-qualifed, and arrays thereof).
1271  } else if (type->isObjCARCImplicitlyUnretainedType()) {
1272    implicitLifetime = Qualifiers::OCL_ExplicitNone;
1273
1274  // If we are in an unevaluated context, like sizeof, skip adding a
1275  // qualification.
1276  } else if (S.isUnevaluatedContext()) {
1277    return type;
1278
1279  // If that failed, give an error and recover using __strong.  __strong
1280  // is the option most likely to prevent spurious second-order diagnostics,
1281  // like when binding a reference to a field.
1282  } else {
1283    // These types can show up in private ivars in system headers, so
1284    // we need this to not be an error in those cases.  Instead we
1285    // want to delay.
1286    if (S.DelayedDiagnostics.shouldDelayDiagnostics()) {
1287      S.DelayedDiagnostics.add(
1288          sema::DelayedDiagnostic::makeForbiddenType(loc,
1289              diag::err_arc_indirect_no_ownership, type, isReference));
1290    } else {
1291      S.Diag(loc, diag::err_arc_indirect_no_ownership) << type << isReference;
1292    }
1293    implicitLifetime = Qualifiers::OCL_Strong;
1294  }
1295  assert(implicitLifetime && "didn't infer any lifetime!");
1296
1297  Qualifiers qs;
1298  qs.addObjCLifetime(implicitLifetime);
1299  return S.Context.getQualifiedType(type, qs);
1300}
1301
1302/// \brief Build a pointer type.
1303///
1304/// \param T The type to which we'll be building a pointer.
1305///
1306/// \param Loc The location of the entity whose type involves this
1307/// pointer type or, if there is no such entity, the location of the
1308/// type that will have pointer type.
1309///
1310/// \param Entity The name of the entity that involves the pointer
1311/// type, if known.
1312///
1313/// \returns A suitable pointer type, if there are no
1314/// errors. Otherwise, returns a NULL type.
1315QualType Sema::BuildPointerType(QualType T,
1316                                SourceLocation Loc, DeclarationName Entity) {
1317  if (T->isReferenceType()) {
1318    // C++ 8.3.2p4: There shall be no ... pointers to references ...
1319    Diag(Loc, diag::err_illegal_decl_pointer_to_reference)
1320      << getPrintableNameForEntity(Entity) << T;
1321    return QualType();
1322  }
1323
1324  assert(!T->isObjCObjectType() && "Should build ObjCObjectPointerType");
1325
1326  // In ARC, it is forbidden to build pointers to unqualified pointers.
1327  if (getLangOpts().ObjCAutoRefCount)
1328    T = inferARCLifetimeForPointee(*this, T, Loc, /*reference*/ false);
1329
1330  // Build the pointer type.
1331  return Context.getPointerType(T);
1332}
1333
1334/// \brief Build a reference type.
1335///
1336/// \param T The type to which we'll be building a reference.
1337///
1338/// \param Loc The location of the entity whose type involves this
1339/// reference type or, if there is no such entity, the location of the
1340/// type that will have reference type.
1341///
1342/// \param Entity The name of the entity that involves the reference
1343/// type, if known.
1344///
1345/// \returns A suitable reference type, if there are no
1346/// errors. Otherwise, returns a NULL type.
1347QualType Sema::BuildReferenceType(QualType T, bool SpelledAsLValue,
1348                                  SourceLocation Loc,
1349                                  DeclarationName Entity) {
1350  assert(Context.getCanonicalType(T) != Context.OverloadTy &&
1351         "Unresolved overloaded function type");
1352
1353  // C++0x [dcl.ref]p6:
1354  //   If a typedef (7.1.3), a type template-parameter (14.3.1), or a
1355  //   decltype-specifier (7.1.6.2) denotes a type TR that is a reference to a
1356  //   type T, an attempt to create the type "lvalue reference to cv TR" creates
1357  //   the type "lvalue reference to T", while an attempt to create the type
1358  //   "rvalue reference to cv TR" creates the type TR.
1359  bool LValueRef = SpelledAsLValue || T->getAs<LValueReferenceType>();
1360
1361  // C++ [dcl.ref]p4: There shall be no references to references.
1362  //
1363  // According to C++ DR 106, references to references are only
1364  // diagnosed when they are written directly (e.g., "int & &"),
1365  // but not when they happen via a typedef:
1366  //
1367  //   typedef int& intref;
1368  //   typedef intref& intref2;
1369  //
1370  // Parser::ParseDeclaratorInternal diagnoses the case where
1371  // references are written directly; here, we handle the
1372  // collapsing of references-to-references as described in C++0x.
1373  // DR 106 and 540 introduce reference-collapsing into C++98/03.
1374
1375  // C++ [dcl.ref]p1:
1376  //   A declarator that specifies the type "reference to cv void"
1377  //   is ill-formed.
1378  if (T->isVoidType()) {
1379    Diag(Loc, diag::err_reference_to_void);
1380    return QualType();
1381  }
1382
1383  // In ARC, it is forbidden to build references to unqualified pointers.
1384  if (getLangOpts().ObjCAutoRefCount)
1385    T = inferARCLifetimeForPointee(*this, T, Loc, /*reference*/ true);
1386
1387  // Handle restrict on references.
1388  if (LValueRef)
1389    return Context.getLValueReferenceType(T, SpelledAsLValue);
1390  return Context.getRValueReferenceType(T);
1391}
1392
1393/// Check whether the specified array size makes the array type a VLA.  If so,
1394/// return true, if not, return the size of the array in SizeVal.
1395static bool isArraySizeVLA(Sema &S, Expr *ArraySize, llvm::APSInt &SizeVal) {
1396  // If the size is an ICE, it certainly isn't a VLA. If we're in a GNU mode
1397  // (like gnu99, but not c99) accept any evaluatable value as an extension.
1398  class VLADiagnoser : public Sema::VerifyICEDiagnoser {
1399  public:
1400    VLADiagnoser() : Sema::VerifyICEDiagnoser(true) {}
1401
1402    virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
1403    }
1404
1405    virtual void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR) {
1406      S.Diag(Loc, diag::ext_vla_folded_to_constant) << SR;
1407    }
1408  } Diagnoser;
1409
1410  return S.VerifyIntegerConstantExpression(ArraySize, &SizeVal, Diagnoser,
1411                                           S.LangOpts.GNUMode).isInvalid();
1412}
1413
1414
1415/// \brief Build an array type.
1416///
1417/// \param T The type of each element in the array.
1418///
1419/// \param ASM C99 array size modifier (e.g., '*', 'static').
1420///
1421/// \param ArraySize Expression describing the size of the array.
1422///
1423/// \param Brackets The range from the opening '[' to the closing ']'.
1424///
1425/// \param Entity The name of the entity that involves the array
1426/// type, if known.
1427///
1428/// \returns A suitable array type, if there are no errors. Otherwise,
1429/// returns a NULL type.
1430QualType Sema::BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
1431                              Expr *ArraySize, unsigned Quals,
1432                              SourceRange Brackets, DeclarationName Entity) {
1433
1434  SourceLocation Loc = Brackets.getBegin();
1435  if (getLangOpts().CPlusPlus) {
1436    // C++ [dcl.array]p1:
1437    //   T is called the array element type; this type shall not be a reference
1438    //   type, the (possibly cv-qualified) type void, a function type or an
1439    //   abstract class type.
1440    //
1441    // C++ [dcl.array]p3:
1442    //   When several "array of" specifications are adjacent, [...] only the
1443    //   first of the constant expressions that specify the bounds of the arrays
1444    //   may be omitted.
1445    //
1446    // Note: function types are handled in the common path with C.
1447    if (T->isReferenceType()) {
1448      Diag(Loc, diag::err_illegal_decl_array_of_references)
1449      << getPrintableNameForEntity(Entity) << T;
1450      return QualType();
1451    }
1452
1453    if (T->isVoidType() || T->isIncompleteArrayType()) {
1454      Diag(Loc, diag::err_illegal_decl_array_incomplete_type) << T;
1455      return QualType();
1456    }
1457
1458    if (RequireNonAbstractType(Brackets.getBegin(), T,
1459                               diag::err_array_of_abstract_type))
1460      return QualType();
1461
1462  } else {
1463    // C99 6.7.5.2p1: If the element type is an incomplete or function type,
1464    // reject it (e.g. void ary[7], struct foo ary[7], void ary[7]())
1465    if (RequireCompleteType(Loc, T,
1466                            diag::err_illegal_decl_array_incomplete_type))
1467      return QualType();
1468  }
1469
1470  if (T->isFunctionType()) {
1471    Diag(Loc, diag::err_illegal_decl_array_of_functions)
1472      << getPrintableNameForEntity(Entity) << T;
1473    return QualType();
1474  }
1475
1476  if (const RecordType *EltTy = T->getAs<RecordType>()) {
1477    // If the element type is a struct or union that contains a variadic
1478    // array, accept it as a GNU extension: C99 6.7.2.1p2.
1479    if (EltTy->getDecl()->hasFlexibleArrayMember())
1480      Diag(Loc, diag::ext_flexible_array_in_array) << T;
1481  } else if (T->isObjCObjectType()) {
1482    Diag(Loc, diag::err_objc_array_of_interfaces) << T;
1483    return QualType();
1484  }
1485
1486  // Do placeholder conversions on the array size expression.
1487  if (ArraySize && ArraySize->hasPlaceholderType()) {
1488    ExprResult Result = CheckPlaceholderExpr(ArraySize);
1489    if (Result.isInvalid()) return QualType();
1490    ArraySize = Result.take();
1491  }
1492
1493  // Do lvalue-to-rvalue conversions on the array size expression.
1494  if (ArraySize && !ArraySize->isRValue()) {
1495    ExprResult Result = DefaultLvalueConversion(ArraySize);
1496    if (Result.isInvalid())
1497      return QualType();
1498
1499    ArraySize = Result.take();
1500  }
1501
1502  // C99 6.7.5.2p1: The size expression shall have integer type.
1503  // C++11 allows contextual conversions to such types.
1504  if (!getLangOpts().CPlusPlus11 &&
1505      ArraySize && !ArraySize->isTypeDependent() &&
1506      !ArraySize->getType()->isIntegralOrUnscopedEnumerationType()) {
1507    Diag(ArraySize->getLocStart(), diag::err_array_size_non_int)
1508      << ArraySize->getType() << ArraySize->getSourceRange();
1509    return QualType();
1510  }
1511
1512  llvm::APSInt ConstVal(Context.getTypeSize(Context.getSizeType()));
1513  if (!ArraySize) {
1514    if (ASM == ArrayType::Star)
1515      T = Context.getVariableArrayType(T, 0, ASM, Quals, Brackets);
1516    else
1517      T = Context.getIncompleteArrayType(T, ASM, Quals);
1518  } else if (ArraySize->isTypeDependent() || ArraySize->isValueDependent()) {
1519    T = Context.getDependentSizedArrayType(T, ArraySize, ASM, Quals, Brackets);
1520  } else if ((!T->isDependentType() && !T->isIncompleteType() &&
1521              !T->isConstantSizeType()) ||
1522             isArraySizeVLA(*this, ArraySize, ConstVal)) {
1523    // Even in C++11, don't allow contextual conversions in the array bound
1524    // of a VLA.
1525    if (getLangOpts().CPlusPlus11 &&
1526        !ArraySize->getType()->isIntegralOrUnscopedEnumerationType()) {
1527      Diag(ArraySize->getLocStart(), diag::err_array_size_non_int)
1528        << ArraySize->getType() << ArraySize->getSourceRange();
1529      return QualType();
1530    }
1531
1532    // C99: an array with an element type that has a non-constant-size is a VLA.
1533    // C99: an array with a non-ICE size is a VLA.  We accept any expression
1534    // that we can fold to a non-zero positive value as an extension.
1535    T = Context.getVariableArrayType(T, ArraySize, ASM, Quals, Brackets);
1536  } else {
1537    // C99 6.7.5.2p1: If the expression is a constant expression, it shall
1538    // have a value greater than zero.
1539    if (ConstVal.isSigned() && ConstVal.isNegative()) {
1540      if (Entity)
1541        Diag(ArraySize->getLocStart(), diag::err_decl_negative_array_size)
1542          << getPrintableNameForEntity(Entity) << ArraySize->getSourceRange();
1543      else
1544        Diag(ArraySize->getLocStart(), diag::err_typecheck_negative_array_size)
1545          << ArraySize->getSourceRange();
1546      return QualType();
1547    }
1548    if (ConstVal == 0) {
1549      // GCC accepts zero sized static arrays. We allow them when
1550      // we're not in a SFINAE context.
1551      Diag(ArraySize->getLocStart(),
1552           isSFINAEContext()? diag::err_typecheck_zero_array_size
1553                            : diag::ext_typecheck_zero_array_size)
1554        << ArraySize->getSourceRange();
1555
1556      if (ASM == ArrayType::Static) {
1557        Diag(ArraySize->getLocStart(),
1558             diag::warn_typecheck_zero_static_array_size)
1559          << ArraySize->getSourceRange();
1560        ASM = ArrayType::Normal;
1561      }
1562    } else if (!T->isDependentType() && !T->isVariablyModifiedType() &&
1563               !T->isIncompleteType()) {
1564      // Is the array too large?
1565      unsigned ActiveSizeBits
1566        = ConstantArrayType::getNumAddressingBits(Context, T, ConstVal);
1567      if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
1568        Diag(ArraySize->getLocStart(), diag::err_array_too_large)
1569          << ConstVal.toString(10)
1570          << ArraySize->getSourceRange();
1571        return QualType();
1572      }
1573    }
1574
1575    T = Context.getConstantArrayType(T, ConstVal, ASM, Quals);
1576  }
1577
1578  // OpenCL v1.2 s6.9.d: variable length arrays are not supported.
1579  if (getLangOpts().OpenCL && T->isVariableArrayType()) {
1580    Diag(Loc, diag::err_opencl_vla);
1581    return QualType();
1582  }
1583  // If this is not C99, extwarn about VLA's and C99 array size modifiers.
1584  if (!getLangOpts().C99) {
1585    if (T->isVariableArrayType()) {
1586      // Prohibit the use of non-POD types in VLAs.
1587      // FIXME: C++1y allows this.
1588      QualType BaseT = Context.getBaseElementType(T);
1589      if (!T->isDependentType() &&
1590          !BaseT.isPODType(Context) &&
1591          !BaseT->isObjCLifetimeType()) {
1592        Diag(Loc, diag::err_vla_non_pod)
1593          << BaseT;
1594        return QualType();
1595      }
1596      // Prohibit the use of VLAs during template argument deduction.
1597      else if (isSFINAEContext()) {
1598        Diag(Loc, diag::err_vla_in_sfinae);
1599        return QualType();
1600      }
1601      // Just extwarn about VLAs.
1602      else
1603        Diag(Loc, getLangOpts().CPlusPlus1y
1604                      ? diag::warn_cxx11_compat_array_of_runtime_bound
1605                      : diag::ext_vla);
1606    } else if (ASM != ArrayType::Normal || Quals != 0)
1607      Diag(Loc,
1608           getLangOpts().CPlusPlus? diag::err_c99_array_usage_cxx
1609                                     : diag::ext_c99_array_usage) << ASM;
1610  }
1611
1612  if (T->isVariableArrayType()) {
1613    // Warn about VLAs for -Wvla.
1614    Diag(Loc, diag::warn_vla_used);
1615  }
1616
1617  return T;
1618}
1619
1620/// \brief Build an ext-vector type.
1621///
1622/// Run the required checks for the extended vector type.
1623QualType Sema::BuildExtVectorType(QualType T, Expr *ArraySize,
1624                                  SourceLocation AttrLoc) {
1625  // unlike gcc's vector_size attribute, we do not allow vectors to be defined
1626  // in conjunction with complex types (pointers, arrays, functions, etc.).
1627  if (!T->isDependentType() &&
1628      !T->isIntegerType() && !T->isRealFloatingType()) {
1629    Diag(AttrLoc, diag::err_attribute_invalid_vector_type) << T;
1630    return QualType();
1631  }
1632
1633  if (!ArraySize->isTypeDependent() && !ArraySize->isValueDependent()) {
1634    llvm::APSInt vecSize(32);
1635    if (!ArraySize->isIntegerConstantExpr(vecSize, Context)) {
1636      Diag(AttrLoc, diag::err_attribute_argument_not_int)
1637        << "ext_vector_type" << ArraySize->getSourceRange();
1638      return QualType();
1639    }
1640
1641    // unlike gcc's vector_size attribute, the size is specified as the
1642    // number of elements, not the number of bytes.
1643    unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue());
1644
1645    if (vectorSize == 0) {
1646      Diag(AttrLoc, diag::err_attribute_zero_size)
1647      << ArraySize->getSourceRange();
1648      return QualType();
1649    }
1650
1651    return Context.getExtVectorType(T, vectorSize);
1652  }
1653
1654  return Context.getDependentSizedExtVectorType(T, ArraySize, AttrLoc);
1655}
1656
1657QualType Sema::BuildFunctionType(QualType T,
1658                                 llvm::MutableArrayRef<QualType> ParamTypes,
1659                                 SourceLocation Loc, DeclarationName Entity,
1660                                 const FunctionProtoType::ExtProtoInfo &EPI) {
1661  if (T->isArrayType() || T->isFunctionType()) {
1662    Diag(Loc, diag::err_func_returning_array_function)
1663      << T->isFunctionType() << T;
1664    return QualType();
1665  }
1666
1667  // Functions cannot return half FP.
1668  if (T->isHalfType()) {
1669    Diag(Loc, diag::err_parameters_retval_cannot_have_fp16_type) << 1 <<
1670      FixItHint::CreateInsertion(Loc, "*");
1671    return QualType();
1672  }
1673
1674  bool Invalid = false;
1675  for (unsigned Idx = 0, Cnt = ParamTypes.size(); Idx < Cnt; ++Idx) {
1676    // FIXME: Loc is too inprecise here, should use proper locations for args.
1677    QualType ParamType = ParamTypes[Idx];
1678    if (ParamType->isVoidType()) {
1679      Diag(Loc, diag::err_param_with_void_type);
1680      Invalid = true;
1681    } else if (ParamType->isHalfType()) {
1682      // Disallow half FP arguments.
1683      Diag(Loc, diag::err_parameters_retval_cannot_have_fp16_type) << 0 <<
1684        FixItHint::CreateInsertion(Loc, "*");
1685      Invalid = true;
1686    }
1687
1688    ParamTypes[Idx] = ParamType;
1689  }
1690
1691  if (Invalid)
1692    return QualType();
1693
1694  return Context.getFunctionType(T, ParamTypes, EPI);
1695}
1696
1697/// \brief Build a member pointer type \c T Class::*.
1698///
1699/// \param T the type to which the member pointer refers.
1700/// \param Class the class type into which the member pointer points.
1701/// \param Loc the location where this type begins
1702/// \param Entity the name of the entity that will have this member pointer type
1703///
1704/// \returns a member pointer type, if successful, or a NULL type if there was
1705/// an error.
1706QualType Sema::BuildMemberPointerType(QualType T, QualType Class,
1707                                      SourceLocation Loc,
1708                                      DeclarationName Entity) {
1709  // Verify that we're not building a pointer to pointer to function with
1710  // exception specification.
1711  if (CheckDistantExceptionSpec(T)) {
1712    Diag(Loc, diag::err_distant_exception_spec);
1713
1714    // FIXME: If we're doing this as part of template instantiation,
1715    // we should return immediately.
1716
1717    // Build the type anyway, but use the canonical type so that the
1718    // exception specifiers are stripped off.
1719    T = Context.getCanonicalType(T);
1720  }
1721
1722  // C++ 8.3.3p3: A pointer to member shall not point to ... a member
1723  //   with reference type, or "cv void."
1724  if (T->isReferenceType()) {
1725    Diag(Loc, diag::err_illegal_decl_mempointer_to_reference)
1726      << (Entity? Entity.getAsString() : "type name") << T;
1727    return QualType();
1728  }
1729
1730  if (T->isVoidType()) {
1731    Diag(Loc, diag::err_illegal_decl_mempointer_to_void)
1732      << (Entity? Entity.getAsString() : "type name");
1733    return QualType();
1734  }
1735
1736  if (!Class->isDependentType() && !Class->isRecordType()) {
1737    Diag(Loc, diag::err_mempointer_in_nonclass_type) << Class;
1738    return QualType();
1739  }
1740
1741  // C++ allows the class type in a member pointer to be an incomplete type.
1742  // In the Microsoft ABI, the size of the member pointer can vary
1743  // according to the class type, which means that we really need a
1744  // complete type if possible, which means we need to instantiate templates.
1745  //
1746  // If template instantiation fails or the type is just incomplete, we have to
1747  // add an extra slot to the member pointer.  Yes, this does cause problems
1748  // when passing pointers between TUs that disagree about the size.
1749  if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1750    CXXRecordDecl *RD = Class->getAsCXXRecordDecl();
1751    if (RD && !RD->hasAttr<MSInheritanceAttr>()) {
1752      // Lock in the inheritance model on the first use of a member pointer.
1753      // Otherwise we may disagree about the size at different points in the TU.
1754      // FIXME: MSVC picks a model on the first use that needs to know the size,
1755      // rather than on the first mention of the type, e.g. typedefs.
1756      if (RequireCompleteType(Loc, Class, 0) && !RD->isBeingDefined()) {
1757        // We know it doesn't have an attribute and it's incomplete, so use the
1758        // unspecified inheritance model.  If we're in the record body, we can
1759        // figure out the inheritance model.
1760        for (CXXRecordDecl::redecl_iterator I = RD->redecls_begin(),
1761             E = RD->redecls_end(); I != E; ++I) {
1762          I->addAttr(::new (Context) UnspecifiedInheritanceAttr(
1763              RD->getSourceRange(), Context));
1764        }
1765      }
1766    }
1767  }
1768
1769  return Context.getMemberPointerType(T, Class.getTypePtr());
1770}
1771
1772/// \brief Build a block pointer type.
1773///
1774/// \param T The type to which we'll be building a block pointer.
1775///
1776/// \param Loc The source location, used for diagnostics.
1777///
1778/// \param Entity The name of the entity that involves the block pointer
1779/// type, if known.
1780///
1781/// \returns A suitable block pointer type, if there are no
1782/// errors. Otherwise, returns a NULL type.
1783QualType Sema::BuildBlockPointerType(QualType T,
1784                                     SourceLocation Loc,
1785                                     DeclarationName Entity) {
1786  if (!T->isFunctionType()) {
1787    Diag(Loc, diag::err_nonfunction_block_type);
1788    return QualType();
1789  }
1790
1791  return Context.getBlockPointerType(T);
1792}
1793
1794QualType Sema::GetTypeFromParser(ParsedType Ty, TypeSourceInfo **TInfo) {
1795  QualType QT = Ty.get();
1796  if (QT.isNull()) {
1797    if (TInfo) *TInfo = 0;
1798    return QualType();
1799  }
1800
1801  TypeSourceInfo *DI = 0;
1802  if (const LocInfoType *LIT = dyn_cast<LocInfoType>(QT)) {
1803    QT = LIT->getType();
1804    DI = LIT->getTypeSourceInfo();
1805  }
1806
1807  if (TInfo) *TInfo = DI;
1808  return QT;
1809}
1810
1811static void transferARCOwnershipToDeclaratorChunk(TypeProcessingState &state,
1812                                            Qualifiers::ObjCLifetime ownership,
1813                                            unsigned chunkIndex);
1814
1815/// Given that this is the declaration of a parameter under ARC,
1816/// attempt to infer attributes and such for pointer-to-whatever
1817/// types.
1818static void inferARCWriteback(TypeProcessingState &state,
1819                              QualType &declSpecType) {
1820  Sema &S = state.getSema();
1821  Declarator &declarator = state.getDeclarator();
1822
1823  // TODO: should we care about decl qualifiers?
1824
1825  // Check whether the declarator has the expected form.  We walk
1826  // from the inside out in order to make the block logic work.
1827  unsigned outermostPointerIndex = 0;
1828  bool isBlockPointer = false;
1829  unsigned numPointers = 0;
1830  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
1831    unsigned chunkIndex = i;
1832    DeclaratorChunk &chunk = declarator.getTypeObject(chunkIndex);
1833    switch (chunk.Kind) {
1834    case DeclaratorChunk::Paren:
1835      // Ignore parens.
1836      break;
1837
1838    case DeclaratorChunk::Reference:
1839    case DeclaratorChunk::Pointer:
1840      // Count the number of pointers.  Treat references
1841      // interchangeably as pointers; if they're mis-ordered, normal
1842      // type building will discover that.
1843      outermostPointerIndex = chunkIndex;
1844      numPointers++;
1845      break;
1846
1847    case DeclaratorChunk::BlockPointer:
1848      // If we have a pointer to block pointer, that's an acceptable
1849      // indirect reference; anything else is not an application of
1850      // the rules.
1851      if (numPointers != 1) return;
1852      numPointers++;
1853      outermostPointerIndex = chunkIndex;
1854      isBlockPointer = true;
1855
1856      // We don't care about pointer structure in return values here.
1857      goto done;
1858
1859    case DeclaratorChunk::Array: // suppress if written (id[])?
1860    case DeclaratorChunk::Function:
1861    case DeclaratorChunk::MemberPointer:
1862      return;
1863    }
1864  }
1865 done:
1866
1867  // If we have *one* pointer, then we want to throw the qualifier on
1868  // the declaration-specifiers, which means that it needs to be a
1869  // retainable object type.
1870  if (numPointers == 1) {
1871    // If it's not a retainable object type, the rule doesn't apply.
1872    if (!declSpecType->isObjCRetainableType()) return;
1873
1874    // If it already has lifetime, don't do anything.
1875    if (declSpecType.getObjCLifetime()) return;
1876
1877    // Otherwise, modify the type in-place.
1878    Qualifiers qs;
1879
1880    if (declSpecType->isObjCARCImplicitlyUnretainedType())
1881      qs.addObjCLifetime(Qualifiers::OCL_ExplicitNone);
1882    else
1883      qs.addObjCLifetime(Qualifiers::OCL_Autoreleasing);
1884    declSpecType = S.Context.getQualifiedType(declSpecType, qs);
1885
1886  // If we have *two* pointers, then we want to throw the qualifier on
1887  // the outermost pointer.
1888  } else if (numPointers == 2) {
1889    // If we don't have a block pointer, we need to check whether the
1890    // declaration-specifiers gave us something that will turn into a
1891    // retainable object pointer after we slap the first pointer on it.
1892    if (!isBlockPointer && !declSpecType->isObjCObjectType())
1893      return;
1894
1895    // Look for an explicit lifetime attribute there.
1896    DeclaratorChunk &chunk = declarator.getTypeObject(outermostPointerIndex);
1897    if (chunk.Kind != DeclaratorChunk::Pointer &&
1898        chunk.Kind != DeclaratorChunk::BlockPointer)
1899      return;
1900    for (const AttributeList *attr = chunk.getAttrs(); attr;
1901           attr = attr->getNext())
1902      if (attr->getKind() == AttributeList::AT_ObjCOwnership)
1903        return;
1904
1905    transferARCOwnershipToDeclaratorChunk(state, Qualifiers::OCL_Autoreleasing,
1906                                          outermostPointerIndex);
1907
1908  // Any other number of pointers/references does not trigger the rule.
1909  } else return;
1910
1911  // TODO: mark whether we did this inference?
1912}
1913
1914static void diagnoseIgnoredQualifiers(
1915    Sema &S, unsigned Quals,
1916    SourceLocation FallbackLoc,
1917    SourceLocation ConstQualLoc = SourceLocation(),
1918    SourceLocation VolatileQualLoc = SourceLocation(),
1919    SourceLocation RestrictQualLoc = SourceLocation(),
1920    SourceLocation AtomicQualLoc = SourceLocation()) {
1921  if (!Quals)
1922    return;
1923
1924  const SourceManager &SM = S.getSourceManager();
1925
1926  struct Qual {
1927    unsigned Mask;
1928    const char *Name;
1929    SourceLocation Loc;
1930  } const QualKinds[4] = {
1931    { DeclSpec::TQ_const, "const", ConstQualLoc },
1932    { DeclSpec::TQ_volatile, "volatile", VolatileQualLoc },
1933    { DeclSpec::TQ_restrict, "restrict", RestrictQualLoc },
1934    { DeclSpec::TQ_atomic, "_Atomic", AtomicQualLoc }
1935  };
1936
1937  llvm::SmallString<32> QualStr;
1938  unsigned NumQuals = 0;
1939  SourceLocation Loc;
1940  FixItHint FixIts[4];
1941
1942  // Build a string naming the redundant qualifiers.
1943  for (unsigned I = 0; I != 4; ++I) {
1944    if (Quals & QualKinds[I].Mask) {
1945      if (!QualStr.empty()) QualStr += ' ';
1946      QualStr += QualKinds[I].Name;
1947
1948      // If we have a location for the qualifier, offer a fixit.
1949      SourceLocation QualLoc = QualKinds[I].Loc;
1950      if (!QualLoc.isInvalid()) {
1951        FixIts[NumQuals] = FixItHint::CreateRemoval(QualLoc);
1952        if (Loc.isInvalid() || SM.isBeforeInTranslationUnit(QualLoc, Loc))
1953          Loc = QualLoc;
1954      }
1955
1956      ++NumQuals;
1957    }
1958  }
1959
1960  S.Diag(Loc.isInvalid() ? FallbackLoc : Loc, diag::warn_qual_return_type)
1961    << QualStr << NumQuals << FixIts[0] << FixIts[1] << FixIts[2] << FixIts[3];
1962}
1963
1964// Diagnose pointless type qualifiers on the return type of a function.
1965static void diagnoseIgnoredFunctionQualifiers(Sema &S, QualType RetTy,
1966                                              Declarator &D,
1967                                              unsigned FunctionChunkIndex) {
1968  if (D.getTypeObject(FunctionChunkIndex).Fun.hasTrailingReturnType()) {
1969    // FIXME: TypeSourceInfo doesn't preserve location information for
1970    // qualifiers.
1971    diagnoseIgnoredQualifiers(S, RetTy.getLocalCVRQualifiers(),
1972                              D.getIdentifierLoc());
1973    return;
1974  }
1975
1976  for (unsigned OuterChunkIndex = FunctionChunkIndex + 1,
1977                End = D.getNumTypeObjects();
1978       OuterChunkIndex != End; ++OuterChunkIndex) {
1979    DeclaratorChunk &OuterChunk = D.getTypeObject(OuterChunkIndex);
1980    switch (OuterChunk.Kind) {
1981    case DeclaratorChunk::Paren:
1982      continue;
1983
1984    case DeclaratorChunk::Pointer: {
1985      DeclaratorChunk::PointerTypeInfo &PTI = OuterChunk.Ptr;
1986      diagnoseIgnoredQualifiers(
1987          S, PTI.TypeQuals,
1988          SourceLocation(),
1989          SourceLocation::getFromRawEncoding(PTI.ConstQualLoc),
1990          SourceLocation::getFromRawEncoding(PTI.VolatileQualLoc),
1991          SourceLocation::getFromRawEncoding(PTI.RestrictQualLoc),
1992          SourceLocation::getFromRawEncoding(PTI.AtomicQualLoc));
1993      return;
1994    }
1995
1996    case DeclaratorChunk::Function:
1997    case DeclaratorChunk::BlockPointer:
1998    case DeclaratorChunk::Reference:
1999    case DeclaratorChunk::Array:
2000    case DeclaratorChunk::MemberPointer:
2001      // FIXME: We can't currently provide an accurate source location and a
2002      // fix-it hint for these.
2003      unsigned AtomicQual = RetTy->isAtomicType() ? DeclSpec::TQ_atomic : 0;
2004      diagnoseIgnoredQualifiers(S, RetTy.getCVRQualifiers() | AtomicQual,
2005                                D.getIdentifierLoc());
2006      return;
2007    }
2008
2009    llvm_unreachable("unknown declarator chunk kind");
2010  }
2011
2012  // If the qualifiers come from a conversion function type, don't diagnose
2013  // them -- they're not necessarily redundant, since such a conversion
2014  // operator can be explicitly called as "x.operator const int()".
2015  if (D.getName().getKind() == UnqualifiedId::IK_ConversionFunctionId)
2016    return;
2017
2018  // Just parens all the way out to the decl specifiers. Diagnose any qualifiers
2019  // which are present there.
2020  diagnoseIgnoredQualifiers(S, D.getDeclSpec().getTypeQualifiers(),
2021                            D.getIdentifierLoc(),
2022                            D.getDeclSpec().getConstSpecLoc(),
2023                            D.getDeclSpec().getVolatileSpecLoc(),
2024                            D.getDeclSpec().getRestrictSpecLoc(),
2025                            D.getDeclSpec().getAtomicSpecLoc());
2026}
2027
2028static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
2029                                             TypeSourceInfo *&ReturnTypeInfo) {
2030  Sema &SemaRef = state.getSema();
2031  Declarator &D = state.getDeclarator();
2032  QualType T;
2033  ReturnTypeInfo = 0;
2034
2035  // The TagDecl owned by the DeclSpec.
2036  TagDecl *OwnedTagDecl = 0;
2037
2038  bool ContainsPlaceholderType = false;
2039
2040  switch (D.getName().getKind()) {
2041  case UnqualifiedId::IK_ImplicitSelfParam:
2042  case UnqualifiedId::IK_OperatorFunctionId:
2043  case UnqualifiedId::IK_Identifier:
2044  case UnqualifiedId::IK_LiteralOperatorId:
2045  case UnqualifiedId::IK_TemplateId:
2046    T = ConvertDeclSpecToType(state);
2047    ContainsPlaceholderType = D.getDeclSpec().containsPlaceholderType();
2048
2049    if (!D.isInvalidType() && D.getDeclSpec().isTypeSpecOwned()) {
2050      OwnedTagDecl = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
2051      // Owned declaration is embedded in declarator.
2052      OwnedTagDecl->setEmbeddedInDeclarator(true);
2053    }
2054    break;
2055
2056  case UnqualifiedId::IK_ConstructorName:
2057  case UnqualifiedId::IK_ConstructorTemplateId:
2058  case UnqualifiedId::IK_DestructorName:
2059    // Constructors and destructors don't have return types. Use
2060    // "void" instead.
2061    T = SemaRef.Context.VoidTy;
2062    if (AttributeList *attrs = D.getDeclSpec().getAttributes().getList())
2063      processTypeAttrs(state, T, TAL_DeclSpec, attrs);
2064    break;
2065
2066  case UnqualifiedId::IK_ConversionFunctionId:
2067    // The result type of a conversion function is the type that it
2068    // converts to.
2069    T = SemaRef.GetTypeFromParser(D.getName().ConversionFunctionId,
2070                                  &ReturnTypeInfo);
2071    ContainsPlaceholderType = T->getContainedAutoType();
2072    break;
2073  }
2074
2075  if (D.getAttributes())
2076    distributeTypeAttrsFromDeclarator(state, T);
2077
2078  // C++11 [dcl.spec.auto]p5: reject 'auto' if it is not in an allowed context.
2079  // In C++11, a function declarator using 'auto' must have a trailing return
2080  // type (this is checked later) and we can skip this. In other languages
2081  // using auto, we need to check regardless.
2082  if (ContainsPlaceholderType &&
2083      (!SemaRef.getLangOpts().CPlusPlus11 || !D.isFunctionDeclarator())) {
2084    int Error = -1;
2085
2086    switch (D.getContext()) {
2087    case Declarator::KNRTypeListContext:
2088      llvm_unreachable("K&R type lists aren't allowed in C++");
2089    case Declarator::LambdaExprContext:
2090      llvm_unreachable("Can't specify a type specifier in lambda grammar");
2091    case Declarator::ObjCParameterContext:
2092    case Declarator::ObjCResultContext:
2093    case Declarator::PrototypeContext:
2094      Error = 0; // Function prototype
2095      break;
2096    case Declarator::MemberContext:
2097      if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_static)
2098        break;
2099      switch (cast<TagDecl>(SemaRef.CurContext)->getTagKind()) {
2100      case TTK_Enum: llvm_unreachable("unhandled tag kind");
2101      case TTK_Struct: Error = 1; /* Struct member */ break;
2102      case TTK_Union:  Error = 2; /* Union member */ break;
2103      case TTK_Class:  Error = 3; /* Class member */ break;
2104      case TTK_Interface: Error = 4; /* Interface member */ break;
2105      }
2106      break;
2107    case Declarator::CXXCatchContext:
2108    case Declarator::ObjCCatchContext:
2109      Error = 5; // Exception declaration
2110      break;
2111    case Declarator::TemplateParamContext:
2112      Error = 6; // Template parameter
2113      break;
2114    case Declarator::BlockLiteralContext:
2115      Error = 7; // Block literal
2116      break;
2117    case Declarator::TemplateTypeArgContext:
2118      Error = 8; // Template type argument
2119      break;
2120    case Declarator::AliasDeclContext:
2121    case Declarator::AliasTemplateContext:
2122      Error = 10; // Type alias
2123      break;
2124    case Declarator::TrailingReturnContext:
2125      if (!SemaRef.getLangOpts().CPlusPlus1y)
2126        Error = 11; // Function return type
2127      break;
2128    case Declarator::ConversionIdContext:
2129      if (!SemaRef.getLangOpts().CPlusPlus1y)
2130        Error = 12; // conversion-type-id
2131      break;
2132    case Declarator::TypeNameContext:
2133      Error = 13; // Generic
2134      break;
2135    case Declarator::FileContext:
2136    case Declarator::BlockContext:
2137    case Declarator::ForContext:
2138    case Declarator::ConditionContext:
2139    case Declarator::CXXNewContext:
2140      break;
2141    }
2142
2143    if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef)
2144      Error = 9;
2145
2146    // In Objective-C it is an error to use 'auto' on a function declarator.
2147    if (D.isFunctionDeclarator())
2148      Error = 11;
2149
2150    // C++11 [dcl.spec.auto]p2: 'auto' is always fine if the declarator
2151    // contains a trailing return type. That is only legal at the outermost
2152    // level. Check all declarator chunks (outermost first) anyway, to give
2153    // better diagnostics.
2154    if (SemaRef.getLangOpts().CPlusPlus11 && Error != -1) {
2155      for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
2156        unsigned chunkIndex = e - i - 1;
2157        state.setCurrentChunkIndex(chunkIndex);
2158        DeclaratorChunk &DeclType = D.getTypeObject(chunkIndex);
2159        if (DeclType.Kind == DeclaratorChunk::Function) {
2160          const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
2161          if (FTI.hasTrailingReturnType()) {
2162            Error = -1;
2163            break;
2164          }
2165        }
2166      }
2167    }
2168
2169    SourceRange AutoRange = D.getDeclSpec().getTypeSpecTypeLoc();
2170    if (D.getName().getKind() == UnqualifiedId::IK_ConversionFunctionId)
2171      AutoRange = D.getName().getSourceRange();
2172
2173    if (Error != -1) {
2174      SemaRef.Diag(AutoRange.getBegin(), diag::err_auto_not_allowed)
2175        << Error << AutoRange;
2176      T = SemaRef.Context.IntTy;
2177      D.setInvalidType(true);
2178    } else
2179      SemaRef.Diag(AutoRange.getBegin(),
2180                   diag::warn_cxx98_compat_auto_type_specifier)
2181        << AutoRange;
2182  }
2183
2184  if (SemaRef.getLangOpts().CPlusPlus &&
2185      OwnedTagDecl && OwnedTagDecl->isCompleteDefinition()) {
2186    // Check the contexts where C++ forbids the declaration of a new class
2187    // or enumeration in a type-specifier-seq.
2188    switch (D.getContext()) {
2189    case Declarator::TrailingReturnContext:
2190      // Class and enumeration definitions are syntactically not allowed in
2191      // trailing return types.
2192      llvm_unreachable("parser should not have allowed this");
2193      break;
2194    case Declarator::FileContext:
2195    case Declarator::MemberContext:
2196    case Declarator::BlockContext:
2197    case Declarator::ForContext:
2198    case Declarator::BlockLiteralContext:
2199    case Declarator::LambdaExprContext:
2200      // C++11 [dcl.type]p3:
2201      //   A type-specifier-seq shall not define a class or enumeration unless
2202      //   it appears in the type-id of an alias-declaration (7.1.3) that is not
2203      //   the declaration of a template-declaration.
2204    case Declarator::AliasDeclContext:
2205      break;
2206    case Declarator::AliasTemplateContext:
2207      SemaRef.Diag(OwnedTagDecl->getLocation(),
2208             diag::err_type_defined_in_alias_template)
2209        << SemaRef.Context.getTypeDeclType(OwnedTagDecl);
2210      D.setInvalidType(true);
2211      break;
2212    case Declarator::TypeNameContext:
2213    case Declarator::ConversionIdContext:
2214    case Declarator::TemplateParamContext:
2215    case Declarator::CXXNewContext:
2216    case Declarator::CXXCatchContext:
2217    case Declarator::ObjCCatchContext:
2218    case Declarator::TemplateTypeArgContext:
2219      SemaRef.Diag(OwnedTagDecl->getLocation(),
2220             diag::err_type_defined_in_type_specifier)
2221        << SemaRef.Context.getTypeDeclType(OwnedTagDecl);
2222      D.setInvalidType(true);
2223      break;
2224    case Declarator::PrototypeContext:
2225    case Declarator::ObjCParameterContext:
2226    case Declarator::ObjCResultContext:
2227    case Declarator::KNRTypeListContext:
2228      // C++ [dcl.fct]p6:
2229      //   Types shall not be defined in return or parameter types.
2230      SemaRef.Diag(OwnedTagDecl->getLocation(),
2231                   diag::err_type_defined_in_param_type)
2232        << SemaRef.Context.getTypeDeclType(OwnedTagDecl);
2233      D.setInvalidType(true);
2234      break;
2235    case Declarator::ConditionContext:
2236      // C++ 6.4p2:
2237      // The type-specifier-seq shall not contain typedef and shall not declare
2238      // a new class or enumeration.
2239      SemaRef.Diag(OwnedTagDecl->getLocation(),
2240                   diag::err_type_defined_in_condition);
2241      D.setInvalidType(true);
2242      break;
2243    }
2244  }
2245
2246  return T;
2247}
2248
2249static std::string getFunctionQualifiersAsString(const FunctionProtoType *FnTy){
2250  std::string Quals =
2251    Qualifiers::fromCVRMask(FnTy->getTypeQuals()).getAsString();
2252
2253  switch (FnTy->getRefQualifier()) {
2254  case RQ_None:
2255    break;
2256
2257  case RQ_LValue:
2258    if (!Quals.empty())
2259      Quals += ' ';
2260    Quals += '&';
2261    break;
2262
2263  case RQ_RValue:
2264    if (!Quals.empty())
2265      Quals += ' ';
2266    Quals += "&&";
2267    break;
2268  }
2269
2270  return Quals;
2271}
2272
2273/// Check that the function type T, which has a cv-qualifier or a ref-qualifier,
2274/// can be contained within the declarator chunk DeclType, and produce an
2275/// appropriate diagnostic if not.
2276static void checkQualifiedFunction(Sema &S, QualType T,
2277                                   DeclaratorChunk &DeclType) {
2278  // C++98 [dcl.fct]p4 / C++11 [dcl.fct]p6: a function type with a
2279  // cv-qualifier or a ref-qualifier can only appear at the topmost level
2280  // of a type.
2281  int DiagKind = -1;
2282  switch (DeclType.Kind) {
2283  case DeclaratorChunk::Paren:
2284  case DeclaratorChunk::MemberPointer:
2285    // These cases are permitted.
2286    return;
2287  case DeclaratorChunk::Array:
2288  case DeclaratorChunk::Function:
2289    // These cases don't allow function types at all; no need to diagnose the
2290    // qualifiers separately.
2291    return;
2292  case DeclaratorChunk::BlockPointer:
2293    DiagKind = 0;
2294    break;
2295  case DeclaratorChunk::Pointer:
2296    DiagKind = 1;
2297    break;
2298  case DeclaratorChunk::Reference:
2299    DiagKind = 2;
2300    break;
2301  }
2302
2303  assert(DiagKind != -1);
2304  S.Diag(DeclType.Loc, diag::err_compound_qualified_function_type)
2305    << DiagKind << isa<FunctionType>(T.IgnoreParens()) << T
2306    << getFunctionQualifiersAsString(T->castAs<FunctionProtoType>());
2307}
2308
2309/// Produce an approprioate diagnostic for an ambiguity between a function
2310/// declarator and a C++ direct-initializer.
2311static void warnAboutAmbiguousFunction(Sema &S, Declarator &D,
2312                                       DeclaratorChunk &DeclType, QualType RT) {
2313  const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
2314  assert(FTI.isAmbiguous && "no direct-initializer / function ambiguity");
2315
2316  // If the return type is void there is no ambiguity.
2317  if (RT->isVoidType())
2318    return;
2319
2320  // An initializer for a non-class type can have at most one argument.
2321  if (!RT->isRecordType() && FTI.NumArgs > 1)
2322    return;
2323
2324  // An initializer for a reference must have exactly one argument.
2325  if (RT->isReferenceType() && FTI.NumArgs != 1)
2326    return;
2327
2328  // Only warn if this declarator is declaring a function at block scope, and
2329  // doesn't have a storage class (such as 'extern') specified.
2330  if (!D.isFunctionDeclarator() ||
2331      D.getFunctionDefinitionKind() != FDK_Declaration ||
2332      !S.CurContext->isFunctionOrMethod() ||
2333      D.getDeclSpec().getStorageClassSpec()
2334        != DeclSpec::SCS_unspecified)
2335    return;
2336
2337  // Inside a condition, a direct initializer is not permitted. We allow one to
2338  // be parsed in order to give better diagnostics in condition parsing.
2339  if (D.getContext() == Declarator::ConditionContext)
2340    return;
2341
2342  SourceRange ParenRange(DeclType.Loc, DeclType.EndLoc);
2343
2344  S.Diag(DeclType.Loc,
2345         FTI.NumArgs ? diag::warn_parens_disambiguated_as_function_declaration
2346                     : diag::warn_empty_parens_are_function_decl)
2347    << ParenRange;
2348
2349  // If the declaration looks like:
2350  //   T var1,
2351  //   f();
2352  // and name lookup finds a function named 'f', then the ',' was
2353  // probably intended to be a ';'.
2354  if (!D.isFirstDeclarator() && D.getIdentifier()) {
2355    FullSourceLoc Comma(D.getCommaLoc(), S.SourceMgr);
2356    FullSourceLoc Name(D.getIdentifierLoc(), S.SourceMgr);
2357    if (Comma.getFileID() != Name.getFileID() ||
2358        Comma.getSpellingLineNumber() != Name.getSpellingLineNumber()) {
2359      LookupResult Result(S, D.getIdentifier(), SourceLocation(),
2360                          Sema::LookupOrdinaryName);
2361      if (S.LookupName(Result, S.getCurScope()))
2362        S.Diag(D.getCommaLoc(), diag::note_empty_parens_function_call)
2363          << FixItHint::CreateReplacement(D.getCommaLoc(), ";")
2364          << D.getIdentifier();
2365    }
2366  }
2367
2368  if (FTI.NumArgs > 0) {
2369    // For a declaration with parameters, eg. "T var(T());", suggest adding parens
2370    // around the first parameter to turn the declaration into a variable
2371    // declaration.
2372    SourceRange Range = FTI.ArgInfo[0].Param->getSourceRange();
2373    SourceLocation B = Range.getBegin();
2374    SourceLocation E = S.PP.getLocForEndOfToken(Range.getEnd());
2375    // FIXME: Maybe we should suggest adding braces instead of parens
2376    // in C++11 for classes that don't have an initializer_list constructor.
2377    S.Diag(B, diag::note_additional_parens_for_variable_declaration)
2378      << FixItHint::CreateInsertion(B, "(")
2379      << FixItHint::CreateInsertion(E, ")");
2380  } else {
2381    // For a declaration without parameters, eg. "T var();", suggest replacing the
2382    // parens with an initializer to turn the declaration into a variable
2383    // declaration.
2384    const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
2385
2386    // Empty parens mean value-initialization, and no parens mean
2387    // default initialization. These are equivalent if the default
2388    // constructor is user-provided or if zero-initialization is a
2389    // no-op.
2390    if (RD && RD->hasDefinition() &&
2391        (RD->isEmpty() || RD->hasUserProvidedDefaultConstructor()))
2392      S.Diag(DeclType.Loc, diag::note_empty_parens_default_ctor)
2393        << FixItHint::CreateRemoval(ParenRange);
2394    else {
2395      std::string Init = S.getFixItZeroInitializerForType(RT);
2396      if (Init.empty() && S.LangOpts.CPlusPlus11)
2397        Init = "{}";
2398      if (!Init.empty())
2399        S.Diag(DeclType.Loc, diag::note_empty_parens_zero_initialize)
2400          << FixItHint::CreateReplacement(ParenRange, Init);
2401    }
2402  }
2403}
2404
2405static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
2406                                                QualType declSpecType,
2407                                                TypeSourceInfo *TInfo) {
2408
2409  QualType T = declSpecType;
2410  Declarator &D = state.getDeclarator();
2411  Sema &S = state.getSema();
2412  ASTContext &Context = S.Context;
2413  const LangOptions &LangOpts = S.getLangOpts();
2414
2415  // The name we're declaring, if any.
2416  DeclarationName Name;
2417  if (D.getIdentifier())
2418    Name = D.getIdentifier();
2419
2420  // Does this declaration declare a typedef-name?
2421  bool IsTypedefName =
2422    D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef ||
2423    D.getContext() == Declarator::AliasDeclContext ||
2424    D.getContext() == Declarator::AliasTemplateContext;
2425
2426  // Does T refer to a function type with a cv-qualifier or a ref-qualifier?
2427  bool IsQualifiedFunction = T->isFunctionProtoType() &&
2428      (T->castAs<FunctionProtoType>()->getTypeQuals() != 0 ||
2429       T->castAs<FunctionProtoType>()->getRefQualifier() != RQ_None);
2430
2431  // If T is 'decltype(auto)', the only declarators we can have are parens
2432  // and at most one function declarator if this is a function declaration.
2433  if (const AutoType *AT = T->getAs<AutoType>()) {
2434    if (AT->isDecltypeAuto()) {
2435      for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
2436        unsigned Index = E - I - 1;
2437        DeclaratorChunk &DeclChunk = D.getTypeObject(Index);
2438        unsigned DiagId = diag::err_decltype_auto_compound_type;
2439        unsigned DiagKind = 0;
2440        switch (DeclChunk.Kind) {
2441        case DeclaratorChunk::Paren:
2442          continue;
2443        case DeclaratorChunk::Function: {
2444          unsigned FnIndex;
2445          if (D.isFunctionDeclarationContext() &&
2446              D.isFunctionDeclarator(FnIndex) && FnIndex == Index)
2447            continue;
2448          DiagId = diag::err_decltype_auto_function_declarator_not_declaration;
2449          break;
2450        }
2451        case DeclaratorChunk::Pointer:
2452        case DeclaratorChunk::BlockPointer:
2453        case DeclaratorChunk::MemberPointer:
2454          DiagKind = 0;
2455          break;
2456        case DeclaratorChunk::Reference:
2457          DiagKind = 1;
2458          break;
2459        case DeclaratorChunk::Array:
2460          DiagKind = 2;
2461          break;
2462        }
2463
2464        S.Diag(DeclChunk.Loc, DiagId) << DiagKind;
2465        D.setInvalidType(true);
2466        break;
2467      }
2468    }
2469  }
2470
2471  // Walk the DeclTypeInfo, building the recursive type as we go.
2472  // DeclTypeInfos are ordered from the identifier out, which is
2473  // opposite of what we want :).
2474  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
2475    unsigned chunkIndex = e - i - 1;
2476    state.setCurrentChunkIndex(chunkIndex);
2477    DeclaratorChunk &DeclType = D.getTypeObject(chunkIndex);
2478    if (IsQualifiedFunction) {
2479      checkQualifiedFunction(S, T, DeclType);
2480      IsQualifiedFunction = DeclType.Kind == DeclaratorChunk::Paren;
2481    }
2482    switch (DeclType.Kind) {
2483    case DeclaratorChunk::Paren:
2484      T = S.BuildParenType(T);
2485      break;
2486    case DeclaratorChunk::BlockPointer:
2487      // If blocks are disabled, emit an error.
2488      if (!LangOpts.Blocks)
2489        S.Diag(DeclType.Loc, diag::err_blocks_disable);
2490
2491      T = S.BuildBlockPointerType(T, D.getIdentifierLoc(), Name);
2492      if (DeclType.Cls.TypeQuals)
2493        T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Cls.TypeQuals);
2494      break;
2495    case DeclaratorChunk::Pointer:
2496      // Verify that we're not building a pointer to pointer to function with
2497      // exception specification.
2498      if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
2499        S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
2500        D.setInvalidType(true);
2501        // Build the type anyway.
2502      }
2503      if (LangOpts.ObjC1 && T->getAs<ObjCObjectType>()) {
2504        T = Context.getObjCObjectPointerType(T);
2505        if (DeclType.Ptr.TypeQuals)
2506          T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Ptr.TypeQuals);
2507        break;
2508      }
2509      T = S.BuildPointerType(T, DeclType.Loc, Name);
2510      if (DeclType.Ptr.TypeQuals)
2511        T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Ptr.TypeQuals);
2512
2513      break;
2514    case DeclaratorChunk::Reference: {
2515      // Verify that we're not building a reference to pointer to function with
2516      // exception specification.
2517      if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
2518        S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
2519        D.setInvalidType(true);
2520        // Build the type anyway.
2521      }
2522      T = S.BuildReferenceType(T, DeclType.Ref.LValueRef, DeclType.Loc, Name);
2523
2524      Qualifiers Quals;
2525      if (DeclType.Ref.HasRestrict)
2526        T = S.BuildQualifiedType(T, DeclType.Loc, Qualifiers::Restrict);
2527      break;
2528    }
2529    case DeclaratorChunk::Array: {
2530      // Verify that we're not building an array of pointers to function with
2531      // exception specification.
2532      if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
2533        S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
2534        D.setInvalidType(true);
2535        // Build the type anyway.
2536      }
2537      DeclaratorChunk::ArrayTypeInfo &ATI = DeclType.Arr;
2538      Expr *ArraySize = static_cast<Expr*>(ATI.NumElts);
2539      ArrayType::ArraySizeModifier ASM;
2540      if (ATI.isStar)
2541        ASM = ArrayType::Star;
2542      else if (ATI.hasStatic)
2543        ASM = ArrayType::Static;
2544      else
2545        ASM = ArrayType::Normal;
2546      if (ASM == ArrayType::Star && !D.isPrototypeContext()) {
2547        // FIXME: This check isn't quite right: it allows star in prototypes
2548        // for function definitions, and disallows some edge cases detailed
2549        // in http://gcc.gnu.org/ml/gcc-patches/2009-02/msg00133.html
2550        S.Diag(DeclType.Loc, diag::err_array_star_outside_prototype);
2551        ASM = ArrayType::Normal;
2552        D.setInvalidType(true);
2553      }
2554
2555      // C99 6.7.5.2p1: The optional type qualifiers and the keyword static
2556      // shall appear only in a declaration of a function parameter with an
2557      // array type, ...
2558      if (ASM == ArrayType::Static || ATI.TypeQuals) {
2559        if (!(D.isPrototypeContext() ||
2560              D.getContext() == Declarator::KNRTypeListContext)) {
2561          S.Diag(DeclType.Loc, diag::err_array_static_outside_prototype) <<
2562              (ASM == ArrayType::Static ? "'static'" : "type qualifier");
2563          // Remove the 'static' and the type qualifiers.
2564          if (ASM == ArrayType::Static)
2565            ASM = ArrayType::Normal;
2566          ATI.TypeQuals = 0;
2567          D.setInvalidType(true);
2568        }
2569
2570        // C99 6.7.5.2p1: ... and then only in the outermost array type
2571        // derivation.
2572        unsigned x = chunkIndex;
2573        while (x != 0) {
2574          // Walk outwards along the declarator chunks.
2575          x--;
2576          const DeclaratorChunk &DC = D.getTypeObject(x);
2577          switch (DC.Kind) {
2578          case DeclaratorChunk::Paren:
2579            continue;
2580          case DeclaratorChunk::Array:
2581          case DeclaratorChunk::Pointer:
2582          case DeclaratorChunk::Reference:
2583          case DeclaratorChunk::MemberPointer:
2584            S.Diag(DeclType.Loc, diag::err_array_static_not_outermost) <<
2585              (ASM == ArrayType::Static ? "'static'" : "type qualifier");
2586            if (ASM == ArrayType::Static)
2587              ASM = ArrayType::Normal;
2588            ATI.TypeQuals = 0;
2589            D.setInvalidType(true);
2590            break;
2591          case DeclaratorChunk::Function:
2592          case DeclaratorChunk::BlockPointer:
2593            // These are invalid anyway, so just ignore.
2594            break;
2595          }
2596        }
2597      }
2598
2599      if (const AutoType *AT = T->getContainedAutoType()) {
2600        // We've already diagnosed this for decltype(auto).
2601        if (!AT->isDecltypeAuto())
2602          S.Diag(DeclType.Loc, diag::err_illegal_decl_array_of_auto)
2603            << getPrintableNameForEntity(Name) << T;
2604        T = QualType();
2605        break;
2606      }
2607
2608      T = S.BuildArrayType(T, ASM, ArraySize, ATI.TypeQuals,
2609                           SourceRange(DeclType.Loc, DeclType.EndLoc), Name);
2610      break;
2611    }
2612    case DeclaratorChunk::Function: {
2613      // If the function declarator has a prototype (i.e. it is not () and
2614      // does not have a K&R-style identifier list), then the arguments are part
2615      // of the type, otherwise the argument list is ().
2616      const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
2617      IsQualifiedFunction = FTI.TypeQuals || FTI.hasRefQualifier();
2618
2619      // Check for auto functions and trailing return type and adjust the
2620      // return type accordingly.
2621      if (!D.isInvalidType()) {
2622        // trailing-return-type is only required if we're declaring a function,
2623        // and not, for instance, a pointer to a function.
2624        if (D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_auto &&
2625            !FTI.hasTrailingReturnType() && chunkIndex == 0 &&
2626            !S.getLangOpts().CPlusPlus1y) {
2627          S.Diag(D.getDeclSpec().getTypeSpecTypeLoc(),
2628               diag::err_auto_missing_trailing_return);
2629          T = Context.IntTy;
2630          D.setInvalidType(true);
2631        } else if (FTI.hasTrailingReturnType()) {
2632          // T must be exactly 'auto' at this point. See CWG issue 681.
2633          if (isa<ParenType>(T)) {
2634            S.Diag(D.getDeclSpec().getTypeSpecTypeLoc(),
2635                 diag::err_trailing_return_in_parens)
2636              << T << D.getDeclSpec().getSourceRange();
2637            D.setInvalidType(true);
2638          } else if (D.getContext() != Declarator::LambdaExprContext &&
2639                     (T.hasQualifiers() || !isa<AutoType>(T) ||
2640                      cast<AutoType>(T)->isDecltypeAuto())) {
2641            S.Diag(D.getDeclSpec().getTypeSpecTypeLoc(),
2642                 diag::err_trailing_return_without_auto)
2643              << T << D.getDeclSpec().getSourceRange();
2644            D.setInvalidType(true);
2645          }
2646          T = S.GetTypeFromParser(FTI.getTrailingReturnType(), &TInfo);
2647          if (T.isNull()) {
2648            // An error occurred parsing the trailing return type.
2649            T = Context.IntTy;
2650            D.setInvalidType(true);
2651          }
2652        }
2653      }
2654
2655      // C99 6.7.5.3p1: The return type may not be a function or array type.
2656      // For conversion functions, we'll diagnose this particular error later.
2657      if ((T->isArrayType() || T->isFunctionType()) &&
2658          (D.getName().getKind() != UnqualifiedId::IK_ConversionFunctionId)) {
2659        unsigned diagID = diag::err_func_returning_array_function;
2660        // Last processing chunk in block context means this function chunk
2661        // represents the block.
2662        if (chunkIndex == 0 &&
2663            D.getContext() == Declarator::BlockLiteralContext)
2664          diagID = diag::err_block_returning_array_function;
2665        S.Diag(DeclType.Loc, diagID) << T->isFunctionType() << T;
2666        T = Context.IntTy;
2667        D.setInvalidType(true);
2668      }
2669
2670      // Do not allow returning half FP value.
2671      // FIXME: This really should be in BuildFunctionType.
2672      if (T->isHalfType()) {
2673        if (S.getLangOpts().OpenCL) {
2674          if (!S.getOpenCLOptions().cl_khr_fp16) {
2675            S.Diag(D.getIdentifierLoc(), diag::err_opencl_half_return) << T;
2676            D.setInvalidType(true);
2677          }
2678        } else {
2679          S.Diag(D.getIdentifierLoc(),
2680            diag::err_parameters_retval_cannot_have_fp16_type) << 1;
2681          D.setInvalidType(true);
2682        }
2683      }
2684
2685      // cv-qualifiers on return types are pointless except when the type is a
2686      // class type in C++.
2687      if ((T.getCVRQualifiers() || T->isAtomicType()) &&
2688          !(S.getLangOpts().CPlusPlus &&
2689            (T->isDependentType() || T->isRecordType())))
2690        diagnoseIgnoredFunctionQualifiers(S, T, D, chunkIndex);
2691
2692      // Objective-C ARC ownership qualifiers are ignored on the function
2693      // return type (by type canonicalization). Complain if this attribute
2694      // was written here.
2695      if (T.getQualifiers().hasObjCLifetime()) {
2696        SourceLocation AttrLoc;
2697        if (chunkIndex + 1 < D.getNumTypeObjects()) {
2698          DeclaratorChunk ReturnTypeChunk = D.getTypeObject(chunkIndex + 1);
2699          for (const AttributeList *Attr = ReturnTypeChunk.getAttrs();
2700               Attr; Attr = Attr->getNext()) {
2701            if (Attr->getKind() == AttributeList::AT_ObjCOwnership) {
2702              AttrLoc = Attr->getLoc();
2703              break;
2704            }
2705          }
2706        }
2707        if (AttrLoc.isInvalid()) {
2708          for (const AttributeList *Attr
2709                 = D.getDeclSpec().getAttributes().getList();
2710               Attr; Attr = Attr->getNext()) {
2711            if (Attr->getKind() == AttributeList::AT_ObjCOwnership) {
2712              AttrLoc = Attr->getLoc();
2713              break;
2714            }
2715          }
2716        }
2717
2718        if (AttrLoc.isValid()) {
2719          // The ownership attributes are almost always written via
2720          // the predefined
2721          // __strong/__weak/__autoreleasing/__unsafe_unretained.
2722          if (AttrLoc.isMacroID())
2723            AttrLoc = S.SourceMgr.getImmediateExpansionRange(AttrLoc).first;
2724
2725          S.Diag(AttrLoc, diag::warn_arc_lifetime_result_type)
2726            << T.getQualifiers().getObjCLifetime();
2727        }
2728      }
2729
2730      if (LangOpts.CPlusPlus && D.getDeclSpec().isTypeSpecOwned()) {
2731        // C++ [dcl.fct]p6:
2732        //   Types shall not be defined in return or parameter types.
2733        TagDecl *Tag = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
2734        if (Tag->isCompleteDefinition())
2735          S.Diag(Tag->getLocation(), diag::err_type_defined_in_result_type)
2736            << Context.getTypeDeclType(Tag);
2737      }
2738
2739      // Exception specs are not allowed in typedefs. Complain, but add it
2740      // anyway.
2741      if (IsTypedefName && FTI.getExceptionSpecType())
2742        S.Diag(FTI.getExceptionSpecLoc(), diag::err_exception_spec_in_typedef)
2743          << (D.getContext() == Declarator::AliasDeclContext ||
2744              D.getContext() == Declarator::AliasTemplateContext);
2745
2746      // If we see "T var();" or "T var(T());" at block scope, it is probably
2747      // an attempt to initialize a variable, not a function declaration.
2748      if (FTI.isAmbiguous)
2749        warnAboutAmbiguousFunction(S, D, DeclType, T);
2750
2751      if (!FTI.NumArgs && !FTI.isVariadic && !LangOpts.CPlusPlus) {
2752        // Simple void foo(), where the incoming T is the result type.
2753        T = Context.getFunctionNoProtoType(T);
2754      } else {
2755        // We allow a zero-parameter variadic function in C if the
2756        // function is marked with the "overloadable" attribute. Scan
2757        // for this attribute now.
2758        if (!FTI.NumArgs && FTI.isVariadic && !LangOpts.CPlusPlus) {
2759          bool Overloadable = false;
2760          for (const AttributeList *Attrs = D.getAttributes();
2761               Attrs; Attrs = Attrs->getNext()) {
2762            if (Attrs->getKind() == AttributeList::AT_Overloadable) {
2763              Overloadable = true;
2764              break;
2765            }
2766          }
2767
2768          if (!Overloadable)
2769            S.Diag(FTI.getEllipsisLoc(), diag::err_ellipsis_first_arg);
2770        }
2771
2772        if (FTI.NumArgs && FTI.ArgInfo[0].Param == 0) {
2773          // C99 6.7.5.3p3: Reject int(x,y,z) when it's not a function
2774          // definition.
2775          S.Diag(FTI.ArgInfo[0].IdentLoc, diag::err_ident_list_in_fn_declaration);
2776          D.setInvalidType(true);
2777          // Recover by creating a K&R-style function type.
2778          T = Context.getFunctionNoProtoType(T);
2779          break;
2780        }
2781
2782        FunctionProtoType::ExtProtoInfo EPI;
2783        EPI.Variadic = FTI.isVariadic;
2784        EPI.HasTrailingReturn = FTI.hasTrailingReturnType();
2785        EPI.TypeQuals = FTI.TypeQuals;
2786        EPI.RefQualifier = !FTI.hasRefQualifier()? RQ_None
2787                    : FTI.RefQualifierIsLValueRef? RQ_LValue
2788                    : RQ_RValue;
2789
2790        // Otherwise, we have a function with an argument list that is
2791        // potentially variadic.
2792        SmallVector<QualType, 16> ArgTys;
2793        ArgTys.reserve(FTI.NumArgs);
2794
2795        SmallVector<bool, 16> ConsumedArguments;
2796        ConsumedArguments.reserve(FTI.NumArgs);
2797        bool HasAnyConsumedArguments = false;
2798
2799        for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) {
2800          ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param);
2801          // Get the type as written.  It will be adjusted later in
2802          // ActOnFunctionDeclarator().
2803          QualType ArgTy = Param->getTypeSourceInfo()->getType();
2804          assert(!ArgTy.isNull() && "Couldn't parse type?");
2805
2806          // Look for 'void'.  void is allowed only as a single argument to a
2807          // function with no other parameters (C99 6.7.5.3p10).  We record
2808          // int(void) as a FunctionProtoType with an empty argument list.
2809          if (ArgTy->isVoidType()) {
2810            // If this is something like 'float(int, void)', reject it.  'void'
2811            // is an incomplete type (C99 6.2.5p19) and function decls cannot
2812            // have arguments of incomplete type.
2813            if (FTI.NumArgs != 1 || FTI.isVariadic) {
2814              S.Diag(DeclType.Loc, diag::err_void_only_param);
2815              ArgTy = Context.IntTy;
2816              Param->setType(ArgTy);
2817            } else if (FTI.ArgInfo[i].Ident) {
2818              // Reject, but continue to parse 'int(void abc)'.
2819              S.Diag(FTI.ArgInfo[i].IdentLoc,
2820                   diag::err_param_with_void_type);
2821              ArgTy = Context.IntTy;
2822              Param->setType(ArgTy);
2823            } else {
2824              // Reject, but continue to parse 'float(const void)'.
2825              if (ArgTy.hasQualifiers())
2826                S.Diag(DeclType.Loc, diag::err_void_param_qualified);
2827
2828              // Do not add 'void' to the ArgTys list.
2829              break;
2830            }
2831          } else if (ArgTy->isHalfType()) {
2832            // Disallow half FP arguments.
2833            // FIXME: This really should be in BuildFunctionType.
2834            if (S.getLangOpts().OpenCL) {
2835              if (!S.getOpenCLOptions().cl_khr_fp16) {
2836                S.Diag(Param->getLocation(),
2837                  diag::err_opencl_half_argument) << ArgTy;
2838                D.setInvalidType();
2839                Param->setInvalidDecl();
2840              }
2841            } else {
2842              S.Diag(Param->getLocation(),
2843                diag::err_parameters_retval_cannot_have_fp16_type) << 0;
2844              D.setInvalidType();
2845            }
2846          } else if (!FTI.hasPrototype) {
2847            if (ArgTy->isPromotableIntegerType()) {
2848              ArgTy = Context.getPromotedIntegerType(ArgTy);
2849              Param->setKNRPromoted(true);
2850            } else if (const BuiltinType* BTy = ArgTy->getAs<BuiltinType>()) {
2851              if (BTy->getKind() == BuiltinType::Float) {
2852                ArgTy = Context.DoubleTy;
2853                Param->setKNRPromoted(true);
2854              }
2855            }
2856          }
2857
2858          if (LangOpts.ObjCAutoRefCount) {
2859            bool Consumed = Param->hasAttr<NSConsumedAttr>();
2860            ConsumedArguments.push_back(Consumed);
2861            HasAnyConsumedArguments |= Consumed;
2862          }
2863
2864          ArgTys.push_back(ArgTy);
2865        }
2866
2867        if (HasAnyConsumedArguments)
2868          EPI.ConsumedArguments = ConsumedArguments.data();
2869
2870        SmallVector<QualType, 4> Exceptions;
2871        SmallVector<ParsedType, 2> DynamicExceptions;
2872        SmallVector<SourceRange, 2> DynamicExceptionRanges;
2873        Expr *NoexceptExpr = 0;
2874
2875        if (FTI.getExceptionSpecType() == EST_Dynamic) {
2876          // FIXME: It's rather inefficient to have to split into two vectors
2877          // here.
2878          unsigned N = FTI.NumExceptions;
2879          DynamicExceptions.reserve(N);
2880          DynamicExceptionRanges.reserve(N);
2881          for (unsigned I = 0; I != N; ++I) {
2882            DynamicExceptions.push_back(FTI.Exceptions[I].Ty);
2883            DynamicExceptionRanges.push_back(FTI.Exceptions[I].Range);
2884          }
2885        } else if (FTI.getExceptionSpecType() == EST_ComputedNoexcept) {
2886          NoexceptExpr = FTI.NoexceptExpr;
2887        }
2888
2889        S.checkExceptionSpecification(FTI.getExceptionSpecType(),
2890                                      DynamicExceptions,
2891                                      DynamicExceptionRanges,
2892                                      NoexceptExpr,
2893                                      Exceptions,
2894                                      EPI);
2895
2896        T = Context.getFunctionType(T, ArgTys, EPI);
2897      }
2898
2899      break;
2900    }
2901    case DeclaratorChunk::MemberPointer:
2902      // The scope spec must refer to a class, or be dependent.
2903      CXXScopeSpec &SS = DeclType.Mem.Scope();
2904      QualType ClsType;
2905      if (SS.isInvalid()) {
2906        // Avoid emitting extra errors if we already errored on the scope.
2907        D.setInvalidType(true);
2908      } else if (S.isDependentScopeSpecifier(SS) ||
2909                 dyn_cast_or_null<CXXRecordDecl>(S.computeDeclContext(SS))) {
2910        NestedNameSpecifier *NNS
2911          = static_cast<NestedNameSpecifier*>(SS.getScopeRep());
2912        NestedNameSpecifier *NNSPrefix = NNS->getPrefix();
2913        switch (NNS->getKind()) {
2914        case NestedNameSpecifier::Identifier:
2915          ClsType = Context.getDependentNameType(ETK_None, NNSPrefix,
2916                                                 NNS->getAsIdentifier());
2917          break;
2918
2919        case NestedNameSpecifier::Namespace:
2920        case NestedNameSpecifier::NamespaceAlias:
2921        case NestedNameSpecifier::Global:
2922          llvm_unreachable("Nested-name-specifier must name a type");
2923
2924        case NestedNameSpecifier::TypeSpec:
2925        case NestedNameSpecifier::TypeSpecWithTemplate:
2926          ClsType = QualType(NNS->getAsType(), 0);
2927          // Note: if the NNS has a prefix and ClsType is a nondependent
2928          // TemplateSpecializationType, then the NNS prefix is NOT included
2929          // in ClsType; hence we wrap ClsType into an ElaboratedType.
2930          // NOTE: in particular, no wrap occurs if ClsType already is an
2931          // Elaborated, DependentName, or DependentTemplateSpecialization.
2932          if (NNSPrefix && isa<TemplateSpecializationType>(NNS->getAsType()))
2933            ClsType = Context.getElaboratedType(ETK_None, NNSPrefix, ClsType);
2934          break;
2935        }
2936      } else {
2937        S.Diag(DeclType.Mem.Scope().getBeginLoc(),
2938             diag::err_illegal_decl_mempointer_in_nonclass)
2939          << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name")
2940          << DeclType.Mem.Scope().getRange();
2941        D.setInvalidType(true);
2942      }
2943
2944      if (!ClsType.isNull())
2945        T = S.BuildMemberPointerType(T, ClsType, DeclType.Loc, D.getIdentifier());
2946      if (T.isNull()) {
2947        T = Context.IntTy;
2948        D.setInvalidType(true);
2949      } else if (DeclType.Mem.TypeQuals) {
2950        T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Mem.TypeQuals);
2951      }
2952      break;
2953    }
2954
2955    if (T.isNull()) {
2956      D.setInvalidType(true);
2957      T = Context.IntTy;
2958    }
2959
2960    // See if there are any attributes on this declarator chunk.
2961    if (AttributeList *attrs = const_cast<AttributeList*>(DeclType.getAttrs()))
2962      processTypeAttrs(state, T, TAL_DeclChunk, attrs);
2963  }
2964
2965  if (LangOpts.CPlusPlus && T->isFunctionType()) {
2966    const FunctionProtoType *FnTy = T->getAs<FunctionProtoType>();
2967    assert(FnTy && "Why oh why is there not a FunctionProtoType here?");
2968
2969    // C++ 8.3.5p4:
2970    //   A cv-qualifier-seq shall only be part of the function type
2971    //   for a nonstatic member function, the function type to which a pointer
2972    //   to member refers, or the top-level function type of a function typedef
2973    //   declaration.
2974    //
2975    // Core issue 547 also allows cv-qualifiers on function types that are
2976    // top-level template type arguments.
2977    bool FreeFunction;
2978    if (!D.getCXXScopeSpec().isSet()) {
2979      FreeFunction = ((D.getContext() != Declarator::MemberContext &&
2980                       D.getContext() != Declarator::LambdaExprContext) ||
2981                      D.getDeclSpec().isFriendSpecified());
2982    } else {
2983      DeclContext *DC = S.computeDeclContext(D.getCXXScopeSpec());
2984      FreeFunction = (DC && !DC->isRecord());
2985    }
2986
2987    // C++11 [dcl.fct]p6 (w/DR1417):
2988    // An attempt to specify a function type with a cv-qualifier-seq or a
2989    // ref-qualifier (including by typedef-name) is ill-formed unless it is:
2990    //  - the function type for a non-static member function,
2991    //  - the function type to which a pointer to member refers,
2992    //  - the top-level function type of a function typedef declaration or
2993    //    alias-declaration,
2994    //  - the type-id in the default argument of a type-parameter, or
2995    //  - the type-id of a template-argument for a type-parameter
2996    if (IsQualifiedFunction &&
2997        !(!FreeFunction &&
2998          D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) &&
2999        !IsTypedefName &&
3000        D.getContext() != Declarator::TemplateTypeArgContext) {
3001      SourceLocation Loc = D.getLocStart();
3002      SourceRange RemovalRange;
3003      unsigned I;
3004      if (D.isFunctionDeclarator(I)) {
3005        SmallVector<SourceLocation, 4> RemovalLocs;
3006        const DeclaratorChunk &Chunk = D.getTypeObject(I);
3007        assert(Chunk.Kind == DeclaratorChunk::Function);
3008        if (Chunk.Fun.hasRefQualifier())
3009          RemovalLocs.push_back(Chunk.Fun.getRefQualifierLoc());
3010        if (Chunk.Fun.TypeQuals & Qualifiers::Const)
3011          RemovalLocs.push_back(Chunk.Fun.getConstQualifierLoc());
3012        if (Chunk.Fun.TypeQuals & Qualifiers::Volatile)
3013          RemovalLocs.push_back(Chunk.Fun.getVolatileQualifierLoc());
3014        // FIXME: We do not track the location of the __restrict qualifier.
3015        //if (Chunk.Fun.TypeQuals & Qualifiers::Restrict)
3016        //  RemovalLocs.push_back(Chunk.Fun.getRestrictQualifierLoc());
3017        if (!RemovalLocs.empty()) {
3018          std::sort(RemovalLocs.begin(), RemovalLocs.end(),
3019                    BeforeThanCompare<SourceLocation>(S.getSourceManager()));
3020          RemovalRange = SourceRange(RemovalLocs.front(), RemovalLocs.back());
3021          Loc = RemovalLocs.front();
3022        }
3023      }
3024
3025      S.Diag(Loc, diag::err_invalid_qualified_function_type)
3026        << FreeFunction << D.isFunctionDeclarator() << T
3027        << getFunctionQualifiersAsString(FnTy)
3028        << FixItHint::CreateRemoval(RemovalRange);
3029
3030      // Strip the cv-qualifiers and ref-qualifiers from the type.
3031      FunctionProtoType::ExtProtoInfo EPI = FnTy->getExtProtoInfo();
3032      EPI.TypeQuals = 0;
3033      EPI.RefQualifier = RQ_None;
3034
3035      T = Context.getFunctionType(FnTy->getResultType(),
3036                                  ArrayRef<QualType>(FnTy->arg_type_begin(),
3037                                                     FnTy->getNumArgs()),
3038                                  EPI);
3039      // Rebuild any parens around the identifier in the function type.
3040      for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
3041        if (D.getTypeObject(i).Kind != DeclaratorChunk::Paren)
3042          break;
3043        T = S.BuildParenType(T);
3044      }
3045    }
3046  }
3047
3048  // Apply any undistributed attributes from the declarator.
3049  if (!T.isNull())
3050    if (AttributeList *attrs = D.getAttributes())
3051      processTypeAttrs(state, T, TAL_DeclName, attrs);
3052
3053  // Diagnose any ignored type attributes.
3054  if (!T.isNull()) state.diagnoseIgnoredTypeAttrs(T);
3055
3056  // C++0x [dcl.constexpr]p9:
3057  //  A constexpr specifier used in an object declaration declares the object
3058  //  as const.
3059  if (D.getDeclSpec().isConstexprSpecified() && T->isObjectType()) {
3060    T.addConst();
3061  }
3062
3063  // If there was an ellipsis in the declarator, the declaration declares a
3064  // parameter pack whose type may be a pack expansion type.
3065  if (D.hasEllipsis() && !T.isNull()) {
3066    // C++0x [dcl.fct]p13:
3067    //   A declarator-id or abstract-declarator containing an ellipsis shall
3068    //   only be used in a parameter-declaration. Such a parameter-declaration
3069    //   is a parameter pack (14.5.3). [...]
3070    switch (D.getContext()) {
3071    case Declarator::PrototypeContext:
3072      // C++0x [dcl.fct]p13:
3073      //   [...] When it is part of a parameter-declaration-clause, the
3074      //   parameter pack is a function parameter pack (14.5.3). The type T
3075      //   of the declarator-id of the function parameter pack shall contain
3076      //   a template parameter pack; each template parameter pack in T is
3077      //   expanded by the function parameter pack.
3078      //
3079      // We represent function parameter packs as function parameters whose
3080      // type is a pack expansion.
3081      if (!T->containsUnexpandedParameterPack()) {
3082        S.Diag(D.getEllipsisLoc(),
3083             diag::err_function_parameter_pack_without_parameter_packs)
3084          << T <<  D.getSourceRange();
3085        D.setEllipsisLoc(SourceLocation());
3086      } else {
3087        T = Context.getPackExpansionType(T, None);
3088      }
3089      break;
3090
3091    case Declarator::TemplateParamContext:
3092      // C++0x [temp.param]p15:
3093      //   If a template-parameter is a [...] is a parameter-declaration that
3094      //   declares a parameter pack (8.3.5), then the template-parameter is a
3095      //   template parameter pack (14.5.3).
3096      //
3097      // Note: core issue 778 clarifies that, if there are any unexpanded
3098      // parameter packs in the type of the non-type template parameter, then
3099      // it expands those parameter packs.
3100      if (T->containsUnexpandedParameterPack())
3101        T = Context.getPackExpansionType(T, None);
3102      else
3103        S.Diag(D.getEllipsisLoc(),
3104               LangOpts.CPlusPlus11
3105                 ? diag::warn_cxx98_compat_variadic_templates
3106                 : diag::ext_variadic_templates);
3107      break;
3108
3109    case Declarator::FileContext:
3110    case Declarator::KNRTypeListContext:
3111    case Declarator::ObjCParameterContext:  // FIXME: special diagnostic here?
3112    case Declarator::ObjCResultContext:     // FIXME: special diagnostic here?
3113    case Declarator::TypeNameContext:
3114    case Declarator::CXXNewContext:
3115    case Declarator::AliasDeclContext:
3116    case Declarator::AliasTemplateContext:
3117    case Declarator::MemberContext:
3118    case Declarator::BlockContext:
3119    case Declarator::ForContext:
3120    case Declarator::ConditionContext:
3121    case Declarator::CXXCatchContext:
3122    case Declarator::ObjCCatchContext:
3123    case Declarator::BlockLiteralContext:
3124    case Declarator::LambdaExprContext:
3125    case Declarator::ConversionIdContext:
3126    case Declarator::TrailingReturnContext:
3127    case Declarator::TemplateTypeArgContext:
3128      // FIXME: We may want to allow parameter packs in block-literal contexts
3129      // in the future.
3130      S.Diag(D.getEllipsisLoc(), diag::err_ellipsis_in_declarator_not_parameter);
3131      D.setEllipsisLoc(SourceLocation());
3132      break;
3133    }
3134  }
3135
3136  if (T.isNull())
3137    return Context.getNullTypeSourceInfo();
3138  else if (D.isInvalidType())
3139    return Context.getTrivialTypeSourceInfo(T);
3140
3141  return S.GetTypeSourceInfoForDeclarator(D, T, TInfo);
3142}
3143
3144/// GetTypeForDeclarator - Convert the type for the specified
3145/// declarator to Type instances.
3146///
3147/// The result of this call will never be null, but the associated
3148/// type may be a null type if there's an unrecoverable error.
3149TypeSourceInfo *Sema::GetTypeForDeclarator(Declarator &D, Scope *S) {
3150  // Determine the type of the declarator. Not all forms of declarator
3151  // have a type.
3152
3153  TypeProcessingState state(*this, D);
3154
3155  TypeSourceInfo *ReturnTypeInfo = 0;
3156  QualType T = GetDeclSpecTypeForDeclarator(state, ReturnTypeInfo);
3157  if (T.isNull())
3158    return Context.getNullTypeSourceInfo();
3159
3160  if (D.isPrototypeContext() && getLangOpts().ObjCAutoRefCount)
3161    inferARCWriteback(state, T);
3162
3163  return GetFullTypeForDeclarator(state, T, ReturnTypeInfo);
3164}
3165
3166static void transferARCOwnershipToDeclSpec(Sema &S,
3167                                           QualType &declSpecTy,
3168                                           Qualifiers::ObjCLifetime ownership) {
3169  if (declSpecTy->isObjCRetainableType() &&
3170      declSpecTy.getObjCLifetime() == Qualifiers::OCL_None) {
3171    Qualifiers qs;
3172    qs.addObjCLifetime(ownership);
3173    declSpecTy = S.Context.getQualifiedType(declSpecTy, qs);
3174  }
3175}
3176
3177static void transferARCOwnershipToDeclaratorChunk(TypeProcessingState &state,
3178                                            Qualifiers::ObjCLifetime ownership,
3179                                            unsigned chunkIndex) {
3180  Sema &S = state.getSema();
3181  Declarator &D = state.getDeclarator();
3182
3183  // Look for an explicit lifetime attribute.
3184  DeclaratorChunk &chunk = D.getTypeObject(chunkIndex);
3185  for (const AttributeList *attr = chunk.getAttrs(); attr;
3186         attr = attr->getNext())
3187    if (attr->getKind() == AttributeList::AT_ObjCOwnership)
3188      return;
3189
3190  const char *attrStr = 0;
3191  switch (ownership) {
3192  case Qualifiers::OCL_None: llvm_unreachable("no ownership!");
3193  case Qualifiers::OCL_ExplicitNone: attrStr = "none"; break;
3194  case Qualifiers::OCL_Strong: attrStr = "strong"; break;
3195  case Qualifiers::OCL_Weak: attrStr = "weak"; break;
3196  case Qualifiers::OCL_Autoreleasing: attrStr = "autoreleasing"; break;
3197  }
3198
3199  // If there wasn't one, add one (with an invalid source location
3200  // so that we don't make an AttributedType for it).
3201  AttributeList *attr = D.getAttributePool()
3202    .create(&S.Context.Idents.get("objc_ownership"), SourceLocation(),
3203            /*scope*/ 0, SourceLocation(),
3204            &S.Context.Idents.get(attrStr), SourceLocation(),
3205            /*args*/ 0, 0, AttributeList::AS_GNU);
3206  spliceAttrIntoList(*attr, chunk.getAttrListRef());
3207
3208  // TODO: mark whether we did this inference?
3209}
3210
3211/// \brief Used for transferring ownership in casts resulting in l-values.
3212static void transferARCOwnership(TypeProcessingState &state,
3213                                 QualType &declSpecTy,
3214                                 Qualifiers::ObjCLifetime ownership) {
3215  Sema &S = state.getSema();
3216  Declarator &D = state.getDeclarator();
3217
3218  int inner = -1;
3219  bool hasIndirection = false;
3220  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
3221    DeclaratorChunk &chunk = D.getTypeObject(i);
3222    switch (chunk.Kind) {
3223    case DeclaratorChunk::Paren:
3224      // Ignore parens.
3225      break;
3226
3227    case DeclaratorChunk::Array:
3228    case DeclaratorChunk::Reference:
3229    case DeclaratorChunk::Pointer:
3230      if (inner != -1)
3231        hasIndirection = true;
3232      inner = i;
3233      break;
3234
3235    case DeclaratorChunk::BlockPointer:
3236      if (inner != -1)
3237        transferARCOwnershipToDeclaratorChunk(state, ownership, i);
3238      return;
3239
3240    case DeclaratorChunk::Function:
3241    case DeclaratorChunk::MemberPointer:
3242      return;
3243    }
3244  }
3245
3246  if (inner == -1)
3247    return;
3248
3249  DeclaratorChunk &chunk = D.getTypeObject(inner);
3250  if (chunk.Kind == DeclaratorChunk::Pointer) {
3251    if (declSpecTy->isObjCRetainableType())
3252      return transferARCOwnershipToDeclSpec(S, declSpecTy, ownership);
3253    if (declSpecTy->isObjCObjectType() && hasIndirection)
3254      return transferARCOwnershipToDeclaratorChunk(state, ownership, inner);
3255  } else {
3256    assert(chunk.Kind == DeclaratorChunk::Array ||
3257           chunk.Kind == DeclaratorChunk::Reference);
3258    return transferARCOwnershipToDeclSpec(S, declSpecTy, ownership);
3259  }
3260}
3261
3262TypeSourceInfo *Sema::GetTypeForDeclaratorCast(Declarator &D, QualType FromTy) {
3263  TypeProcessingState state(*this, D);
3264
3265  TypeSourceInfo *ReturnTypeInfo = 0;
3266  QualType declSpecTy = GetDeclSpecTypeForDeclarator(state, ReturnTypeInfo);
3267  if (declSpecTy.isNull())
3268    return Context.getNullTypeSourceInfo();
3269
3270  if (getLangOpts().ObjCAutoRefCount) {
3271    Qualifiers::ObjCLifetime ownership = Context.getInnerObjCOwnership(FromTy);
3272    if (ownership != Qualifiers::OCL_None)
3273      transferARCOwnership(state, declSpecTy, ownership);
3274  }
3275
3276  return GetFullTypeForDeclarator(state, declSpecTy, ReturnTypeInfo);
3277}
3278
3279/// Map an AttributedType::Kind to an AttributeList::Kind.
3280static AttributeList::Kind getAttrListKind(AttributedType::Kind kind) {
3281  switch (kind) {
3282  case AttributedType::attr_address_space:
3283    return AttributeList::AT_AddressSpace;
3284  case AttributedType::attr_regparm:
3285    return AttributeList::AT_Regparm;
3286  case AttributedType::attr_vector_size:
3287    return AttributeList::AT_VectorSize;
3288  case AttributedType::attr_neon_vector_type:
3289    return AttributeList::AT_NeonVectorType;
3290  case AttributedType::attr_neon_polyvector_type:
3291    return AttributeList::AT_NeonPolyVectorType;
3292  case AttributedType::attr_objc_gc:
3293    return AttributeList::AT_ObjCGC;
3294  case AttributedType::attr_objc_ownership:
3295    return AttributeList::AT_ObjCOwnership;
3296  case AttributedType::attr_noreturn:
3297    return AttributeList::AT_NoReturn;
3298  case AttributedType::attr_cdecl:
3299    return AttributeList::AT_CDecl;
3300  case AttributedType::attr_fastcall:
3301    return AttributeList::AT_FastCall;
3302  case AttributedType::attr_stdcall:
3303    return AttributeList::AT_StdCall;
3304  case AttributedType::attr_thiscall:
3305    return AttributeList::AT_ThisCall;
3306  case AttributedType::attr_pascal:
3307    return AttributeList::AT_Pascal;
3308  case AttributedType::attr_pcs:
3309    return AttributeList::AT_Pcs;
3310  case AttributedType::attr_pnaclcall:
3311    return AttributeList::AT_PnaclCall;
3312  case AttributedType::attr_inteloclbicc:
3313    return AttributeList::AT_IntelOclBicc;
3314  case AttributedType::attr_ptr32:
3315    return AttributeList::AT_Ptr32;
3316  case AttributedType::attr_ptr64:
3317    return AttributeList::AT_Ptr64;
3318  case AttributedType::attr_sptr:
3319    return AttributeList::AT_SPtr;
3320  case AttributedType::attr_uptr:
3321    return AttributeList::AT_UPtr;
3322  }
3323  llvm_unreachable("unexpected attribute kind!");
3324}
3325
3326static void fillAttributedTypeLoc(AttributedTypeLoc TL,
3327                                  const AttributeList *attrs) {
3328  AttributedType::Kind kind = TL.getAttrKind();
3329
3330  assert(attrs && "no type attributes in the expected location!");
3331  AttributeList::Kind parsedKind = getAttrListKind(kind);
3332  while (attrs->getKind() != parsedKind) {
3333    attrs = attrs->getNext();
3334    assert(attrs && "no matching attribute in expected location!");
3335  }
3336
3337  TL.setAttrNameLoc(attrs->getLoc());
3338  if (TL.hasAttrExprOperand())
3339    TL.setAttrExprOperand(attrs->getArg(0));
3340  else if (TL.hasAttrEnumOperand())
3341    TL.setAttrEnumOperandLoc(attrs->getParameterLoc());
3342
3343  // FIXME: preserve this information to here.
3344  if (TL.hasAttrOperand())
3345    TL.setAttrOperandParensRange(SourceRange());
3346}
3347
3348namespace {
3349  class TypeSpecLocFiller : public TypeLocVisitor<TypeSpecLocFiller> {
3350    ASTContext &Context;
3351    const DeclSpec &DS;
3352
3353  public:
3354    TypeSpecLocFiller(ASTContext &Context, const DeclSpec &DS)
3355      : Context(Context), DS(DS) {}
3356
3357    void VisitAttributedTypeLoc(AttributedTypeLoc TL) {
3358      fillAttributedTypeLoc(TL, DS.getAttributes().getList());
3359      Visit(TL.getModifiedLoc());
3360    }
3361    void VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
3362      Visit(TL.getUnqualifiedLoc());
3363    }
3364    void VisitTypedefTypeLoc(TypedefTypeLoc TL) {
3365      TL.setNameLoc(DS.getTypeSpecTypeLoc());
3366    }
3367    void VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
3368      TL.setNameLoc(DS.getTypeSpecTypeLoc());
3369      // FIXME. We should have DS.getTypeSpecTypeEndLoc(). But, it requires
3370      // addition field. What we have is good enough for dispay of location
3371      // of 'fixit' on interface name.
3372      TL.setNameEndLoc(DS.getLocEnd());
3373    }
3374    void VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
3375      // Handle the base type, which might not have been written explicitly.
3376      if (DS.getTypeSpecType() == DeclSpec::TST_unspecified) {
3377        TL.setHasBaseTypeAsWritten(false);
3378        TL.getBaseLoc().initialize(Context, SourceLocation());
3379      } else {
3380        TL.setHasBaseTypeAsWritten(true);
3381        Visit(TL.getBaseLoc());
3382      }
3383
3384      // Protocol qualifiers.
3385      if (DS.getProtocolQualifiers()) {
3386        assert(TL.getNumProtocols() > 0);
3387        assert(TL.getNumProtocols() == DS.getNumProtocolQualifiers());
3388        TL.setLAngleLoc(DS.getProtocolLAngleLoc());
3389        TL.setRAngleLoc(DS.getSourceRange().getEnd());
3390        for (unsigned i = 0, e = DS.getNumProtocolQualifiers(); i != e; ++i)
3391          TL.setProtocolLoc(i, DS.getProtocolLocs()[i]);
3392      } else {
3393        assert(TL.getNumProtocols() == 0);
3394        TL.setLAngleLoc(SourceLocation());
3395        TL.setRAngleLoc(SourceLocation());
3396      }
3397    }
3398    void VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
3399      TL.setStarLoc(SourceLocation());
3400      Visit(TL.getPointeeLoc());
3401    }
3402    void VisitTemplateSpecializationTypeLoc(TemplateSpecializationTypeLoc TL) {
3403      TypeSourceInfo *TInfo = 0;
3404      Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3405
3406      // If we got no declarator info from previous Sema routines,
3407      // just fill with the typespec loc.
3408      if (!TInfo) {
3409        TL.initialize(Context, DS.getTypeSpecTypeNameLoc());
3410        return;
3411      }
3412
3413      TypeLoc OldTL = TInfo->getTypeLoc();
3414      if (TInfo->getType()->getAs<ElaboratedType>()) {
3415        ElaboratedTypeLoc ElabTL = OldTL.castAs<ElaboratedTypeLoc>();
3416        TemplateSpecializationTypeLoc NamedTL = ElabTL.getNamedTypeLoc()
3417            .castAs<TemplateSpecializationTypeLoc>();
3418        TL.copy(NamedTL);
3419      } else {
3420        TL.copy(OldTL.castAs<TemplateSpecializationTypeLoc>());
3421        assert(TL.getRAngleLoc() == OldTL.castAs<TemplateSpecializationTypeLoc>().getRAngleLoc());
3422      }
3423
3424    }
3425    void VisitTypeOfExprTypeLoc(TypeOfExprTypeLoc TL) {
3426      assert(DS.getTypeSpecType() == DeclSpec::TST_typeofExpr);
3427      TL.setTypeofLoc(DS.getTypeSpecTypeLoc());
3428      TL.setParensRange(DS.getTypeofParensRange());
3429    }
3430    void VisitTypeOfTypeLoc(TypeOfTypeLoc TL) {
3431      assert(DS.getTypeSpecType() == DeclSpec::TST_typeofType);
3432      TL.setTypeofLoc(DS.getTypeSpecTypeLoc());
3433      TL.setParensRange(DS.getTypeofParensRange());
3434      assert(DS.getRepAsType());
3435      TypeSourceInfo *TInfo = 0;
3436      Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3437      TL.setUnderlyingTInfo(TInfo);
3438    }
3439    void VisitUnaryTransformTypeLoc(UnaryTransformTypeLoc TL) {
3440      // FIXME: This holds only because we only have one unary transform.
3441      assert(DS.getTypeSpecType() == DeclSpec::TST_underlyingType);
3442      TL.setKWLoc(DS.getTypeSpecTypeLoc());
3443      TL.setParensRange(DS.getTypeofParensRange());
3444      assert(DS.getRepAsType());
3445      TypeSourceInfo *TInfo = 0;
3446      Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3447      TL.setUnderlyingTInfo(TInfo);
3448    }
3449    void VisitBuiltinTypeLoc(BuiltinTypeLoc TL) {
3450      // By default, use the source location of the type specifier.
3451      TL.setBuiltinLoc(DS.getTypeSpecTypeLoc());
3452      if (TL.needsExtraLocalData()) {
3453        // Set info for the written builtin specifiers.
3454        TL.getWrittenBuiltinSpecs() = DS.getWrittenBuiltinSpecs();
3455        // Try to have a meaningful source location.
3456        if (TL.getWrittenSignSpec() != TSS_unspecified)
3457          // Sign spec loc overrides the others (e.g., 'unsigned long').
3458          TL.setBuiltinLoc(DS.getTypeSpecSignLoc());
3459        else if (TL.getWrittenWidthSpec() != TSW_unspecified)
3460          // Width spec loc overrides type spec loc (e.g., 'short int').
3461          TL.setBuiltinLoc(DS.getTypeSpecWidthLoc());
3462      }
3463    }
3464    void VisitElaboratedTypeLoc(ElaboratedTypeLoc TL) {
3465      ElaboratedTypeKeyword Keyword
3466        = TypeWithKeyword::getKeywordForTypeSpec(DS.getTypeSpecType());
3467      if (DS.getTypeSpecType() == TST_typename) {
3468        TypeSourceInfo *TInfo = 0;
3469        Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3470        if (TInfo) {
3471          TL.copy(TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>());
3472          return;
3473        }
3474      }
3475      TL.setElaboratedKeywordLoc(Keyword != ETK_None
3476                                 ? DS.getTypeSpecTypeLoc()
3477                                 : SourceLocation());
3478      const CXXScopeSpec& SS = DS.getTypeSpecScope();
3479      TL.setQualifierLoc(SS.getWithLocInContext(Context));
3480      Visit(TL.getNextTypeLoc().getUnqualifiedLoc());
3481    }
3482    void VisitDependentNameTypeLoc(DependentNameTypeLoc TL) {
3483      assert(DS.getTypeSpecType() == TST_typename);
3484      TypeSourceInfo *TInfo = 0;
3485      Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3486      assert(TInfo);
3487      TL.copy(TInfo->getTypeLoc().castAs<DependentNameTypeLoc>());
3488    }
3489    void VisitDependentTemplateSpecializationTypeLoc(
3490                                 DependentTemplateSpecializationTypeLoc TL) {
3491      assert(DS.getTypeSpecType() == TST_typename);
3492      TypeSourceInfo *TInfo = 0;
3493      Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3494      assert(TInfo);
3495      TL.copy(
3496          TInfo->getTypeLoc().castAs<DependentTemplateSpecializationTypeLoc>());
3497    }
3498    void VisitTagTypeLoc(TagTypeLoc TL) {
3499      TL.setNameLoc(DS.getTypeSpecTypeNameLoc());
3500    }
3501    void VisitAtomicTypeLoc(AtomicTypeLoc TL) {
3502      // An AtomicTypeLoc can come from either an _Atomic(...) type specifier
3503      // or an _Atomic qualifier.
3504      if (DS.getTypeSpecType() == DeclSpec::TST_atomic) {
3505        TL.setKWLoc(DS.getTypeSpecTypeLoc());
3506        TL.setParensRange(DS.getTypeofParensRange());
3507
3508        TypeSourceInfo *TInfo = 0;
3509        Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
3510        assert(TInfo);
3511        TL.getValueLoc().initializeFullCopy(TInfo->getTypeLoc());
3512      } else {
3513        TL.setKWLoc(DS.getAtomicSpecLoc());
3514        // No parens, to indicate this was spelled as an _Atomic qualifier.
3515        TL.setParensRange(SourceRange());
3516        Visit(TL.getValueLoc());
3517      }
3518    }
3519
3520    void VisitTypeLoc(TypeLoc TL) {
3521      // FIXME: add other typespec types and change this to an assert.
3522      TL.initialize(Context, DS.getTypeSpecTypeLoc());
3523    }
3524  };
3525
3526  class DeclaratorLocFiller : public TypeLocVisitor<DeclaratorLocFiller> {
3527    ASTContext &Context;
3528    const DeclaratorChunk &Chunk;
3529
3530  public:
3531    DeclaratorLocFiller(ASTContext &Context, const DeclaratorChunk &Chunk)
3532      : Context(Context), Chunk(Chunk) {}
3533
3534    void VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
3535      llvm_unreachable("qualified type locs not expected here!");
3536    }
3537
3538    void VisitAttributedTypeLoc(AttributedTypeLoc TL) {
3539      fillAttributedTypeLoc(TL, Chunk.getAttrs());
3540    }
3541    void VisitBlockPointerTypeLoc(BlockPointerTypeLoc TL) {
3542      assert(Chunk.Kind == DeclaratorChunk::BlockPointer);
3543      TL.setCaretLoc(Chunk.Loc);
3544    }
3545    void VisitPointerTypeLoc(PointerTypeLoc TL) {
3546      assert(Chunk.Kind == DeclaratorChunk::Pointer);
3547      TL.setStarLoc(Chunk.Loc);
3548    }
3549    void VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
3550      assert(Chunk.Kind == DeclaratorChunk::Pointer);
3551      TL.setStarLoc(Chunk.Loc);
3552    }
3553    void VisitMemberPointerTypeLoc(MemberPointerTypeLoc TL) {
3554      assert(Chunk.Kind == DeclaratorChunk::MemberPointer);
3555      const CXXScopeSpec& SS = Chunk.Mem.Scope();
3556      NestedNameSpecifierLoc NNSLoc = SS.getWithLocInContext(Context);
3557
3558      const Type* ClsTy = TL.getClass();
3559      QualType ClsQT = QualType(ClsTy, 0);
3560      TypeSourceInfo *ClsTInfo = Context.CreateTypeSourceInfo(ClsQT, 0);
3561      // Now copy source location info into the type loc component.
3562      TypeLoc ClsTL = ClsTInfo->getTypeLoc();
3563      switch (NNSLoc.getNestedNameSpecifier()->getKind()) {
3564      case NestedNameSpecifier::Identifier:
3565        assert(isa<DependentNameType>(ClsTy) && "Unexpected TypeLoc");
3566        {
3567          DependentNameTypeLoc DNTLoc = ClsTL.castAs<DependentNameTypeLoc>();
3568          DNTLoc.setElaboratedKeywordLoc(SourceLocation());
3569          DNTLoc.setQualifierLoc(NNSLoc.getPrefix());
3570          DNTLoc.setNameLoc(NNSLoc.getLocalBeginLoc());
3571        }
3572        break;
3573
3574      case NestedNameSpecifier::TypeSpec:
3575      case NestedNameSpecifier::TypeSpecWithTemplate:
3576        if (isa<ElaboratedType>(ClsTy)) {
3577          ElaboratedTypeLoc ETLoc = ClsTL.castAs<ElaboratedTypeLoc>();
3578          ETLoc.setElaboratedKeywordLoc(SourceLocation());
3579          ETLoc.setQualifierLoc(NNSLoc.getPrefix());
3580          TypeLoc NamedTL = ETLoc.getNamedTypeLoc();
3581          NamedTL.initializeFullCopy(NNSLoc.getTypeLoc());
3582        } else {
3583          ClsTL.initializeFullCopy(NNSLoc.getTypeLoc());
3584        }
3585        break;
3586
3587      case NestedNameSpecifier::Namespace:
3588      case NestedNameSpecifier::NamespaceAlias:
3589      case NestedNameSpecifier::Global:
3590        llvm_unreachable("Nested-name-specifier must name a type");
3591      }
3592
3593      // Finally fill in MemberPointerLocInfo fields.
3594      TL.setStarLoc(Chunk.Loc);
3595      TL.setClassTInfo(ClsTInfo);
3596    }
3597    void VisitLValueReferenceTypeLoc(LValueReferenceTypeLoc TL) {
3598      assert(Chunk.Kind == DeclaratorChunk::Reference);
3599      // 'Amp' is misleading: this might have been originally
3600      /// spelled with AmpAmp.
3601      TL.setAmpLoc(Chunk.Loc);
3602    }
3603    void VisitRValueReferenceTypeLoc(RValueReferenceTypeLoc TL) {
3604      assert(Chunk.Kind == DeclaratorChunk::Reference);
3605      assert(!Chunk.Ref.LValueRef);
3606      TL.setAmpAmpLoc(Chunk.Loc);
3607    }
3608    void VisitArrayTypeLoc(ArrayTypeLoc TL) {
3609      assert(Chunk.Kind == DeclaratorChunk::Array);
3610      TL.setLBracketLoc(Chunk.Loc);
3611      TL.setRBracketLoc(Chunk.EndLoc);
3612      TL.setSizeExpr(static_cast<Expr*>(Chunk.Arr.NumElts));
3613    }
3614    void VisitFunctionTypeLoc(FunctionTypeLoc TL) {
3615      assert(Chunk.Kind == DeclaratorChunk::Function);
3616      TL.setLocalRangeBegin(Chunk.Loc);
3617      TL.setLocalRangeEnd(Chunk.EndLoc);
3618
3619      const DeclaratorChunk::FunctionTypeInfo &FTI = Chunk.Fun;
3620      TL.setLParenLoc(FTI.getLParenLoc());
3621      TL.setRParenLoc(FTI.getRParenLoc());
3622      for (unsigned i = 0, e = TL.getNumArgs(), tpi = 0; i != e; ++i) {
3623        ParmVarDecl *Param = cast<ParmVarDecl>(FTI.ArgInfo[i].Param);
3624        TL.setArg(tpi++, Param);
3625      }
3626      // FIXME: exception specs
3627    }
3628    void VisitParenTypeLoc(ParenTypeLoc TL) {
3629      assert(Chunk.Kind == DeclaratorChunk::Paren);
3630      TL.setLParenLoc(Chunk.Loc);
3631      TL.setRParenLoc(Chunk.EndLoc);
3632    }
3633
3634    void VisitTypeLoc(TypeLoc TL) {
3635      llvm_unreachable("unsupported TypeLoc kind in declarator!");
3636    }
3637  };
3638}
3639
3640static void fillAtomicQualLoc(AtomicTypeLoc ATL, const DeclaratorChunk &Chunk) {
3641  SourceLocation Loc;
3642  switch (Chunk.Kind) {
3643  case DeclaratorChunk::Function:
3644  case DeclaratorChunk::Array:
3645  case DeclaratorChunk::Paren:
3646    llvm_unreachable("cannot be _Atomic qualified");
3647
3648  case DeclaratorChunk::Pointer:
3649    Loc = SourceLocation::getFromRawEncoding(Chunk.Ptr.AtomicQualLoc);
3650    break;
3651
3652  case DeclaratorChunk::BlockPointer:
3653  case DeclaratorChunk::Reference:
3654  case DeclaratorChunk::MemberPointer:
3655    // FIXME: Provide a source location for the _Atomic keyword.
3656    break;
3657  }
3658
3659  ATL.setKWLoc(Loc);
3660  ATL.setParensRange(SourceRange());
3661}
3662
3663/// \brief Create and instantiate a TypeSourceInfo with type source information.
3664///
3665/// \param T QualType referring to the type as written in source code.
3666///
3667/// \param ReturnTypeInfo For declarators whose return type does not show
3668/// up in the normal place in the declaration specifiers (such as a C++
3669/// conversion function), this pointer will refer to a type source information
3670/// for that return type.
3671TypeSourceInfo *
3672Sema::GetTypeSourceInfoForDeclarator(Declarator &D, QualType T,
3673                                     TypeSourceInfo *ReturnTypeInfo) {
3674  TypeSourceInfo *TInfo = Context.CreateTypeSourceInfo(T);
3675  UnqualTypeLoc CurrTL = TInfo->getTypeLoc().getUnqualifiedLoc();
3676
3677  // Handle parameter packs whose type is a pack expansion.
3678  if (isa<PackExpansionType>(T)) {
3679    CurrTL.castAs<PackExpansionTypeLoc>().setEllipsisLoc(D.getEllipsisLoc());
3680    CurrTL = CurrTL.getNextTypeLoc().getUnqualifiedLoc();
3681  }
3682
3683  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
3684    // An AtomicTypeLoc might be produced by an atomic qualifier in this
3685    // declarator chunk.
3686    if (AtomicTypeLoc ATL = CurrTL.getAs<AtomicTypeLoc>()) {
3687      fillAtomicQualLoc(ATL, D.getTypeObject(i));
3688      CurrTL = ATL.getValueLoc().getUnqualifiedLoc();
3689    }
3690
3691    while (AttributedTypeLoc TL = CurrTL.getAs<AttributedTypeLoc>()) {
3692      fillAttributedTypeLoc(TL, D.getTypeObject(i).getAttrs());
3693      CurrTL = TL.getNextTypeLoc().getUnqualifiedLoc();
3694    }
3695
3696    DeclaratorLocFiller(Context, D.getTypeObject(i)).Visit(CurrTL);
3697    CurrTL = CurrTL.getNextTypeLoc().getUnqualifiedLoc();
3698  }
3699
3700  // If we have different source information for the return type, use
3701  // that.  This really only applies to C++ conversion functions.
3702  if (ReturnTypeInfo) {
3703    TypeLoc TL = ReturnTypeInfo->getTypeLoc();
3704    assert(TL.getFullDataSize() == CurrTL.getFullDataSize());
3705    memcpy(CurrTL.getOpaqueData(), TL.getOpaqueData(), TL.getFullDataSize());
3706  } else {
3707    TypeSpecLocFiller(Context, D.getDeclSpec()).Visit(CurrTL);
3708  }
3709
3710  return TInfo;
3711}
3712
3713/// \brief Create a LocInfoType to hold the given QualType and TypeSourceInfo.
3714ParsedType Sema::CreateParsedType(QualType T, TypeSourceInfo *TInfo) {
3715  // FIXME: LocInfoTypes are "transient", only needed for passing to/from Parser
3716  // and Sema during declaration parsing. Try deallocating/caching them when
3717  // it's appropriate, instead of allocating them and keeping them around.
3718  LocInfoType *LocT = (LocInfoType*)BumpAlloc.Allocate(sizeof(LocInfoType),
3719                                                       TypeAlignment);
3720  new (LocT) LocInfoType(T, TInfo);
3721  assert(LocT->getTypeClass() != T->getTypeClass() &&
3722         "LocInfoType's TypeClass conflicts with an existing Type class");
3723  return ParsedType::make(QualType(LocT, 0));
3724}
3725
3726void LocInfoType::getAsStringInternal(std::string &Str,
3727                                      const PrintingPolicy &Policy) const {
3728  llvm_unreachable("LocInfoType leaked into the type system; an opaque TypeTy*"
3729         " was used directly instead of getting the QualType through"
3730         " GetTypeFromParser");
3731}
3732
3733TypeResult Sema::ActOnTypeName(Scope *S, Declarator &D) {
3734  // C99 6.7.6: Type names have no identifier.  This is already validated by
3735  // the parser.
3736  assert(D.getIdentifier() == 0 && "Type name should have no identifier!");
3737
3738  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
3739  QualType T = TInfo->getType();
3740  if (D.isInvalidType())
3741    return true;
3742
3743  // Make sure there are no unused decl attributes on the declarator.
3744  // We don't want to do this for ObjC parameters because we're going
3745  // to apply them to the actual parameter declaration.
3746  // Likewise, we don't want to do this for alias declarations, because
3747  // we are actually going to build a declaration from this eventually.
3748  if (D.getContext() != Declarator::ObjCParameterContext &&
3749      D.getContext() != Declarator::AliasDeclContext &&
3750      D.getContext() != Declarator::AliasTemplateContext)
3751    checkUnusedDeclAttributes(D);
3752
3753  if (getLangOpts().CPlusPlus) {
3754    // Check that there are no default arguments (C++ only).
3755    CheckExtraCXXDefaultArguments(D);
3756  }
3757
3758  return CreateParsedType(T, TInfo);
3759}
3760
3761ParsedType Sema::ActOnObjCInstanceType(SourceLocation Loc) {
3762  QualType T = Context.getObjCInstanceType();
3763  TypeSourceInfo *TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
3764  return CreateParsedType(T, TInfo);
3765}
3766
3767
3768//===----------------------------------------------------------------------===//
3769// Type Attribute Processing
3770//===----------------------------------------------------------------------===//
3771
3772/// HandleAddressSpaceTypeAttribute - Process an address_space attribute on the
3773/// specified type.  The attribute contains 1 argument, the id of the address
3774/// space for the type.
3775static void HandleAddressSpaceTypeAttribute(QualType &Type,
3776                                            const AttributeList &Attr, Sema &S){
3777
3778  // If this type is already address space qualified, reject it.
3779  // ISO/IEC TR 18037 S5.3 (amending C99 6.7.3): "No type shall be qualified by
3780  // qualifiers for two or more different address spaces."
3781  if (Type.getAddressSpace()) {
3782    S.Diag(Attr.getLoc(), diag::err_attribute_address_multiple_qualifiers);
3783    Attr.setInvalid();
3784    return;
3785  }
3786
3787  // ISO/IEC TR 18037 S5.3 (amending C99 6.7.3): "A function type shall not be
3788  // qualified by an address-space qualifier."
3789  if (Type->isFunctionType()) {
3790    S.Diag(Attr.getLoc(), diag::err_attribute_address_function_type);
3791    Attr.setInvalid();
3792    return;
3793  }
3794
3795  // Check the attribute arguments.
3796  if (Attr.getNumArgs() != 1) {
3797    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
3798    Attr.setInvalid();
3799    return;
3800  }
3801  Expr *ASArgExpr = static_cast<Expr *>(Attr.getArg(0));
3802  llvm::APSInt addrSpace(32);
3803  if (ASArgExpr->isTypeDependent() || ASArgExpr->isValueDependent() ||
3804      !ASArgExpr->isIntegerConstantExpr(addrSpace, S.Context)) {
3805    S.Diag(Attr.getLoc(), diag::err_attribute_address_space_not_int)
3806      << ASArgExpr->getSourceRange();
3807    Attr.setInvalid();
3808    return;
3809  }
3810
3811  // Bounds checking.
3812  if (addrSpace.isSigned()) {
3813    if (addrSpace.isNegative()) {
3814      S.Diag(Attr.getLoc(), diag::err_attribute_address_space_negative)
3815        << ASArgExpr->getSourceRange();
3816      Attr.setInvalid();
3817      return;
3818    }
3819    addrSpace.setIsSigned(false);
3820  }
3821  llvm::APSInt max(addrSpace.getBitWidth());
3822  max = Qualifiers::MaxAddressSpace;
3823  if (addrSpace > max) {
3824    S.Diag(Attr.getLoc(), diag::err_attribute_address_space_too_high)
3825      << Qualifiers::MaxAddressSpace << ASArgExpr->getSourceRange();
3826    Attr.setInvalid();
3827    return;
3828  }
3829
3830  unsigned ASIdx = static_cast<unsigned>(addrSpace.getZExtValue());
3831  Type = S.Context.getAddrSpaceQualType(Type, ASIdx);
3832}
3833
3834/// Does this type have a "direct" ownership qualifier?  That is,
3835/// is it written like "__strong id", as opposed to something like
3836/// "typeof(foo)", where that happens to be strong?
3837static bool hasDirectOwnershipQualifier(QualType type) {
3838  // Fast path: no qualifier at all.
3839  assert(type.getQualifiers().hasObjCLifetime());
3840
3841  while (true) {
3842    // __strong id
3843    if (const AttributedType *attr = dyn_cast<AttributedType>(type)) {
3844      if (attr->getAttrKind() == AttributedType::attr_objc_ownership)
3845        return true;
3846
3847      type = attr->getModifiedType();
3848
3849    // X *__strong (...)
3850    } else if (const ParenType *paren = dyn_cast<ParenType>(type)) {
3851      type = paren->getInnerType();
3852
3853    // That's it for things we want to complain about.  In particular,
3854    // we do not want to look through typedefs, typeof(expr),
3855    // typeof(type), or any other way that the type is somehow
3856    // abstracted.
3857    } else {
3858
3859      return false;
3860    }
3861  }
3862}
3863
3864/// handleObjCOwnershipTypeAttr - Process an objc_ownership
3865/// attribute on the specified type.
3866///
3867/// Returns 'true' if the attribute was handled.
3868static bool handleObjCOwnershipTypeAttr(TypeProcessingState &state,
3869                                       AttributeList &attr,
3870                                       QualType &type) {
3871  bool NonObjCPointer = false;
3872
3873  if (!type->isDependentType() && !type->isUndeducedType()) {
3874    if (const PointerType *ptr = type->getAs<PointerType>()) {
3875      QualType pointee = ptr->getPointeeType();
3876      if (pointee->isObjCRetainableType() || pointee->isPointerType())
3877        return false;
3878      // It is important not to lose the source info that there was an attribute
3879      // applied to non-objc pointer. We will create an attributed type but
3880      // its type will be the same as the original type.
3881      NonObjCPointer = true;
3882    } else if (!type->isObjCRetainableType()) {
3883      return false;
3884    }
3885
3886    // Don't accept an ownership attribute in the declspec if it would
3887    // just be the return type of a block pointer.
3888    if (state.isProcessingDeclSpec()) {
3889      Declarator &D = state.getDeclarator();
3890      if (maybeMovePastReturnType(D, D.getNumTypeObjects()))
3891        return false;
3892    }
3893  }
3894
3895  Sema &S = state.getSema();
3896  SourceLocation AttrLoc = attr.getLoc();
3897  if (AttrLoc.isMacroID())
3898    AttrLoc = S.getSourceManager().getImmediateExpansionRange(AttrLoc).first;
3899
3900  if (!attr.getParameterName()) {
3901    S.Diag(AttrLoc, diag::err_attribute_argument_n_not_string)
3902      << "objc_ownership" << 1;
3903    attr.setInvalid();
3904    return true;
3905  }
3906
3907  // Consume lifetime attributes without further comment outside of
3908  // ARC mode.
3909  if (!S.getLangOpts().ObjCAutoRefCount)
3910    return true;
3911
3912  Qualifiers::ObjCLifetime lifetime;
3913  if (attr.getParameterName()->isStr("none"))
3914    lifetime = Qualifiers::OCL_ExplicitNone;
3915  else if (attr.getParameterName()->isStr("strong"))
3916    lifetime = Qualifiers::OCL_Strong;
3917  else if (attr.getParameterName()->isStr("weak"))
3918    lifetime = Qualifiers::OCL_Weak;
3919  else if (attr.getParameterName()->isStr("autoreleasing"))
3920    lifetime = Qualifiers::OCL_Autoreleasing;
3921  else {
3922    S.Diag(AttrLoc, diag::warn_attribute_type_not_supported)
3923      << "objc_ownership" << attr.getParameterName();
3924    attr.setInvalid();
3925    return true;
3926  }
3927
3928  SplitQualType underlyingType = type.split();
3929
3930  // Check for redundant/conflicting ownership qualifiers.
3931  if (Qualifiers::ObjCLifetime previousLifetime
3932        = type.getQualifiers().getObjCLifetime()) {
3933    // If it's written directly, that's an error.
3934    if (hasDirectOwnershipQualifier(type)) {
3935      S.Diag(AttrLoc, diag::err_attr_objc_ownership_redundant)
3936        << type;
3937      return true;
3938    }
3939
3940    // Otherwise, if the qualifiers actually conflict, pull sugar off
3941    // until we reach a type that is directly qualified.
3942    if (previousLifetime != lifetime) {
3943      // This should always terminate: the canonical type is
3944      // qualified, so some bit of sugar must be hiding it.
3945      while (!underlyingType.Quals.hasObjCLifetime()) {
3946        underlyingType = underlyingType.getSingleStepDesugaredType();
3947      }
3948      underlyingType.Quals.removeObjCLifetime();
3949    }
3950  }
3951
3952  underlyingType.Quals.addObjCLifetime(lifetime);
3953
3954  if (NonObjCPointer) {
3955    StringRef name = attr.getName()->getName();
3956    switch (lifetime) {
3957    case Qualifiers::OCL_None:
3958    case Qualifiers::OCL_ExplicitNone:
3959      break;
3960    case Qualifiers::OCL_Strong: name = "__strong"; break;
3961    case Qualifiers::OCL_Weak: name = "__weak"; break;
3962    case Qualifiers::OCL_Autoreleasing: name = "__autoreleasing"; break;
3963    }
3964    S.Diag(AttrLoc, diag::warn_objc_object_attribute_wrong_type)
3965      << name << type;
3966  }
3967
3968  QualType origType = type;
3969  if (!NonObjCPointer)
3970    type = S.Context.getQualifiedType(underlyingType);
3971
3972  // If we have a valid source location for the attribute, use an
3973  // AttributedType instead.
3974  if (AttrLoc.isValid())
3975    type = S.Context.getAttributedType(AttributedType::attr_objc_ownership,
3976                                       origType, type);
3977
3978  // Forbid __weak if the runtime doesn't support it.
3979  if (lifetime == Qualifiers::OCL_Weak &&
3980      !S.getLangOpts().ObjCARCWeak && !NonObjCPointer) {
3981
3982    // Actually, delay this until we know what we're parsing.
3983    if (S.DelayedDiagnostics.shouldDelayDiagnostics()) {
3984      S.DelayedDiagnostics.add(
3985          sema::DelayedDiagnostic::makeForbiddenType(
3986              S.getSourceManager().getExpansionLoc(AttrLoc),
3987              diag::err_arc_weak_no_runtime, type, /*ignored*/ 0));
3988    } else {
3989      S.Diag(AttrLoc, diag::err_arc_weak_no_runtime);
3990    }
3991
3992    attr.setInvalid();
3993    return true;
3994  }
3995
3996  // Forbid __weak for class objects marked as
3997  // objc_arc_weak_reference_unavailable
3998  if (lifetime == Qualifiers::OCL_Weak) {
3999    if (const ObjCObjectPointerType *ObjT =
4000          type->getAs<ObjCObjectPointerType>()) {
4001      if (ObjCInterfaceDecl *Class = ObjT->getInterfaceDecl()) {
4002        if (Class->isArcWeakrefUnavailable()) {
4003            S.Diag(AttrLoc, diag::err_arc_unsupported_weak_class);
4004            S.Diag(ObjT->getInterfaceDecl()->getLocation(),
4005                   diag::note_class_declared);
4006        }
4007      }
4008    }
4009  }
4010
4011  return true;
4012}
4013
4014/// handleObjCGCTypeAttr - Process the __attribute__((objc_gc)) type
4015/// attribute on the specified type.  Returns true to indicate that
4016/// the attribute was handled, false to indicate that the type does
4017/// not permit the attribute.
4018static bool handleObjCGCTypeAttr(TypeProcessingState &state,
4019                                 AttributeList &attr,
4020                                 QualType &type) {
4021  Sema &S = state.getSema();
4022
4023  // Delay if this isn't some kind of pointer.
4024  if (!type->isPointerType() &&
4025      !type->isObjCObjectPointerType() &&
4026      !type->isBlockPointerType())
4027    return false;
4028
4029  if (type.getObjCGCAttr() != Qualifiers::GCNone) {
4030    S.Diag(attr.getLoc(), diag::err_attribute_multiple_objc_gc);
4031    attr.setInvalid();
4032    return true;
4033  }
4034
4035  // Check the attribute arguments.
4036  if (!attr.getParameterName()) {
4037    S.Diag(attr.getLoc(), diag::err_attribute_argument_n_not_string)
4038      << "objc_gc" << 1;
4039    attr.setInvalid();
4040    return true;
4041  }
4042  Qualifiers::GC GCAttr;
4043  if (attr.getNumArgs() != 0) {
4044    S.Diag(attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
4045    attr.setInvalid();
4046    return true;
4047  }
4048  if (attr.getParameterName()->isStr("weak"))
4049    GCAttr = Qualifiers::Weak;
4050  else if (attr.getParameterName()->isStr("strong"))
4051    GCAttr = Qualifiers::Strong;
4052  else {
4053    S.Diag(attr.getLoc(), diag::warn_attribute_type_not_supported)
4054      << "objc_gc" << attr.getParameterName();
4055    attr.setInvalid();
4056    return true;
4057  }
4058
4059  QualType origType = type;
4060  type = S.Context.getObjCGCQualType(origType, GCAttr);
4061
4062  // Make an attributed type to preserve the source information.
4063  if (attr.getLoc().isValid())
4064    type = S.Context.getAttributedType(AttributedType::attr_objc_gc,
4065                                       origType, type);
4066
4067  return true;
4068}
4069
4070namespace {
4071  /// A helper class to unwrap a type down to a function for the
4072  /// purposes of applying attributes there.
4073  ///
4074  /// Use:
4075  ///   FunctionTypeUnwrapper unwrapped(SemaRef, T);
4076  ///   if (unwrapped.isFunctionType()) {
4077  ///     const FunctionType *fn = unwrapped.get();
4078  ///     // change fn somehow
4079  ///     T = unwrapped.wrap(fn);
4080  ///   }
4081  struct FunctionTypeUnwrapper {
4082    enum WrapKind {
4083      Desugar,
4084      Parens,
4085      Pointer,
4086      BlockPointer,
4087      Reference,
4088      MemberPointer
4089    };
4090
4091    QualType Original;
4092    const FunctionType *Fn;
4093    SmallVector<unsigned char /*WrapKind*/, 8> Stack;
4094
4095    FunctionTypeUnwrapper(Sema &S, QualType T) : Original(T) {
4096      while (true) {
4097        const Type *Ty = T.getTypePtr();
4098        if (isa<FunctionType>(Ty)) {
4099          Fn = cast<FunctionType>(Ty);
4100          return;
4101        } else if (isa<ParenType>(Ty)) {
4102          T = cast<ParenType>(Ty)->getInnerType();
4103          Stack.push_back(Parens);
4104        } else if (isa<PointerType>(Ty)) {
4105          T = cast<PointerType>(Ty)->getPointeeType();
4106          Stack.push_back(Pointer);
4107        } else if (isa<BlockPointerType>(Ty)) {
4108          T = cast<BlockPointerType>(Ty)->getPointeeType();
4109          Stack.push_back(BlockPointer);
4110        } else if (isa<MemberPointerType>(Ty)) {
4111          T = cast<MemberPointerType>(Ty)->getPointeeType();
4112          Stack.push_back(MemberPointer);
4113        } else if (isa<ReferenceType>(Ty)) {
4114          T = cast<ReferenceType>(Ty)->getPointeeType();
4115          Stack.push_back(Reference);
4116        } else {
4117          const Type *DTy = Ty->getUnqualifiedDesugaredType();
4118          if (Ty == DTy) {
4119            Fn = 0;
4120            return;
4121          }
4122
4123          T = QualType(DTy, 0);
4124          Stack.push_back(Desugar);
4125        }
4126      }
4127    }
4128
4129    bool isFunctionType() const { return (Fn != 0); }
4130    const FunctionType *get() const { return Fn; }
4131
4132    QualType wrap(Sema &S, const FunctionType *New) {
4133      // If T wasn't modified from the unwrapped type, do nothing.
4134      if (New == get()) return Original;
4135
4136      Fn = New;
4137      return wrap(S.Context, Original, 0);
4138    }
4139
4140  private:
4141    QualType wrap(ASTContext &C, QualType Old, unsigned I) {
4142      if (I == Stack.size())
4143        return C.getQualifiedType(Fn, Old.getQualifiers());
4144
4145      // Build up the inner type, applying the qualifiers from the old
4146      // type to the new type.
4147      SplitQualType SplitOld = Old.split();
4148
4149      // As a special case, tail-recurse if there are no qualifiers.
4150      if (SplitOld.Quals.empty())
4151        return wrap(C, SplitOld.Ty, I);
4152      return C.getQualifiedType(wrap(C, SplitOld.Ty, I), SplitOld.Quals);
4153    }
4154
4155    QualType wrap(ASTContext &C, const Type *Old, unsigned I) {
4156      if (I == Stack.size()) return QualType(Fn, 0);
4157
4158      switch (static_cast<WrapKind>(Stack[I++])) {
4159      case Desugar:
4160        // This is the point at which we potentially lose source
4161        // information.
4162        return wrap(C, Old->getUnqualifiedDesugaredType(), I);
4163
4164      case Parens: {
4165        QualType New = wrap(C, cast<ParenType>(Old)->getInnerType(), I);
4166        return C.getParenType(New);
4167      }
4168
4169      case Pointer: {
4170        QualType New = wrap(C, cast<PointerType>(Old)->getPointeeType(), I);
4171        return C.getPointerType(New);
4172      }
4173
4174      case BlockPointer: {
4175        QualType New = wrap(C, cast<BlockPointerType>(Old)->getPointeeType(),I);
4176        return C.getBlockPointerType(New);
4177      }
4178
4179      case MemberPointer: {
4180        const MemberPointerType *OldMPT = cast<MemberPointerType>(Old);
4181        QualType New = wrap(C, OldMPT->getPointeeType(), I);
4182        return C.getMemberPointerType(New, OldMPT->getClass());
4183      }
4184
4185      case Reference: {
4186        const ReferenceType *OldRef = cast<ReferenceType>(Old);
4187        QualType New = wrap(C, OldRef->getPointeeType(), I);
4188        if (isa<LValueReferenceType>(OldRef))
4189          return C.getLValueReferenceType(New, OldRef->isSpelledAsLValue());
4190        else
4191          return C.getRValueReferenceType(New);
4192      }
4193      }
4194
4195      llvm_unreachable("unknown wrapping kind");
4196    }
4197  };
4198}
4199
4200static bool handleMSPointerTypeQualifierAttr(TypeProcessingState &State,
4201                                             AttributeList &Attr,
4202                                             QualType &Type) {
4203  Sema &S = State.getSema();
4204
4205  AttributeList::Kind Kind = Attr.getKind();
4206  QualType Desugared = Type;
4207  const AttributedType *AT = dyn_cast<AttributedType>(Type);
4208  while (AT) {
4209    AttributedType::Kind CurAttrKind = AT->getAttrKind();
4210
4211    // You cannot specify duplicate type attributes, so if the attribute has
4212    // already been applied, flag it.
4213    if (getAttrListKind(CurAttrKind) == Kind) {
4214      S.Diag(Attr.getLoc(), diag::warn_duplicate_attribute_exact)
4215        << Attr.getName();
4216      return true;
4217    }
4218
4219    // You cannot have both __sptr and __uptr on the same type, nor can you
4220    // have __ptr32 and __ptr64.
4221    if ((CurAttrKind == AttributedType::attr_ptr32 &&
4222         Kind == AttributeList::AT_Ptr64) ||
4223        (CurAttrKind == AttributedType::attr_ptr64 &&
4224         Kind == AttributeList::AT_Ptr32)) {
4225      S.Diag(Attr.getLoc(), diag::err_attributes_are_not_compatible)
4226        << "'__ptr32'" << "'__ptr64'";
4227      return true;
4228    } else if ((CurAttrKind == AttributedType::attr_sptr &&
4229                Kind == AttributeList::AT_UPtr) ||
4230               (CurAttrKind == AttributedType::attr_uptr &&
4231                Kind == AttributeList::AT_SPtr)) {
4232      S.Diag(Attr.getLoc(), diag::err_attributes_are_not_compatible)
4233        << "'__sptr'" << "'__uptr'";
4234      return true;
4235    }
4236
4237    Desugared = AT->getEquivalentType();
4238    AT = dyn_cast<AttributedType>(Desugared);
4239  }
4240
4241  // Pointer type qualifiers can only operate on pointer types, but not
4242  // pointer-to-member types.
4243  if (!isa<PointerType>(Desugared)) {
4244    S.Diag(Attr.getLoc(), Type->isMemberPointerType() ?
4245                          diag::err_attribute_no_member_pointers :
4246                          diag::err_attribute_pointers_only) << Attr.getName();
4247    return true;
4248  }
4249
4250  AttributedType::Kind TAK;
4251  switch (Kind) {
4252  default: llvm_unreachable("Unknown attribute kind");
4253  case AttributeList::AT_Ptr32: TAK = AttributedType::attr_ptr32; break;
4254  case AttributeList::AT_Ptr64: TAK = AttributedType::attr_ptr64; break;
4255  case AttributeList::AT_SPtr: TAK = AttributedType::attr_sptr; break;
4256  case AttributeList::AT_UPtr: TAK = AttributedType::attr_uptr; break;
4257  }
4258
4259  Type = S.Context.getAttributedType(TAK, Type, Type);
4260  return false;
4261}
4262
4263/// Process an individual function attribute.  Returns true to
4264/// indicate that the attribute was handled, false if it wasn't.
4265static bool handleFunctionTypeAttr(TypeProcessingState &state,
4266                                   AttributeList &attr,
4267                                   QualType &type) {
4268  Sema &S = state.getSema();
4269
4270  FunctionTypeUnwrapper unwrapped(S, type);
4271
4272  if (attr.getKind() == AttributeList::AT_NoReturn) {
4273    if (S.CheckNoReturnAttr(attr))
4274      return true;
4275
4276    // Delay if this is not a function type.
4277    if (!unwrapped.isFunctionType())
4278      return false;
4279
4280    // Otherwise we can process right away.
4281    FunctionType::ExtInfo EI = unwrapped.get()->getExtInfo().withNoReturn(true);
4282    type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
4283    return true;
4284  }
4285
4286  // ns_returns_retained is not always a type attribute, but if we got
4287  // here, we're treating it as one right now.
4288  if (attr.getKind() == AttributeList::AT_NSReturnsRetained) {
4289    assert(S.getLangOpts().ObjCAutoRefCount &&
4290           "ns_returns_retained treated as type attribute in non-ARC");
4291    if (attr.getNumArgs()) return true;
4292
4293    // Delay if this is not a function type.
4294    if (!unwrapped.isFunctionType())
4295      return false;
4296
4297    FunctionType::ExtInfo EI
4298      = unwrapped.get()->getExtInfo().withProducesResult(true);
4299    type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
4300    return true;
4301  }
4302
4303  if (attr.getKind() == AttributeList::AT_Regparm) {
4304    unsigned value;
4305    if (S.CheckRegparmAttr(attr, value))
4306      return true;
4307
4308    // Delay if this is not a function type.
4309    if (!unwrapped.isFunctionType())
4310      return false;
4311
4312    // Diagnose regparm with fastcall.
4313    const FunctionType *fn = unwrapped.get();
4314    CallingConv CC = fn->getCallConv();
4315    if (CC == CC_X86FastCall) {
4316      S.Diag(attr.getLoc(), diag::err_attributes_are_not_compatible)
4317        << FunctionType::getNameForCallConv(CC)
4318        << "regparm";
4319      attr.setInvalid();
4320      return true;
4321    }
4322
4323    FunctionType::ExtInfo EI =
4324      unwrapped.get()->getExtInfo().withRegParm(value);
4325    type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
4326    return true;
4327  }
4328
4329  // Delay if the type didn't work out to a function.
4330  if (!unwrapped.isFunctionType()) return false;
4331
4332  // Otherwise, a calling convention.
4333  CallingConv CC;
4334  if (S.CheckCallingConvAttr(attr, CC))
4335    return true;
4336
4337  const FunctionType *fn = unwrapped.get();
4338  CallingConv CCOld = fn->getCallConv();
4339  if (S.Context.getCanonicalCallConv(CC) ==
4340      S.Context.getCanonicalCallConv(CCOld)) {
4341    FunctionType::ExtInfo EI= unwrapped.get()->getExtInfo().withCallingConv(CC);
4342    type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
4343    return true;
4344  }
4345
4346  if (CCOld != (S.LangOpts.MRTD ? CC_X86StdCall : CC_Default)) {
4347    // Should we diagnose reapplications of the same convention?
4348    S.Diag(attr.getLoc(), diag::err_attributes_are_not_compatible)
4349      << FunctionType::getNameForCallConv(CC)
4350      << FunctionType::getNameForCallConv(CCOld);
4351    attr.setInvalid();
4352    return true;
4353  }
4354
4355  // Diagnose the use of X86 fastcall on varargs or unprototyped functions.
4356  if (CC == CC_X86FastCall) {
4357    if (isa<FunctionNoProtoType>(fn)) {
4358      S.Diag(attr.getLoc(), diag::err_cconv_knr)
4359        << FunctionType::getNameForCallConv(CC);
4360      attr.setInvalid();
4361      return true;
4362    }
4363
4364    const FunctionProtoType *FnP = cast<FunctionProtoType>(fn);
4365    if (FnP->isVariadic()) {
4366      S.Diag(attr.getLoc(), diag::err_cconv_varargs)
4367        << FunctionType::getNameForCallConv(CC);
4368      attr.setInvalid();
4369      return true;
4370    }
4371
4372    // Also diagnose fastcall with regparm.
4373    if (fn->getHasRegParm()) {
4374      S.Diag(attr.getLoc(), diag::err_attributes_are_not_compatible)
4375        << "regparm"
4376        << FunctionType::getNameForCallConv(CC);
4377      attr.setInvalid();
4378      return true;
4379    }
4380  }
4381
4382  FunctionType::ExtInfo EI = unwrapped.get()->getExtInfo().withCallingConv(CC);
4383  type = unwrapped.wrap(S, S.Context.adjustFunctionType(unwrapped.get(), EI));
4384  return true;
4385}
4386
4387/// Handle OpenCL image access qualifiers: read_only, write_only, read_write
4388static void HandleOpenCLImageAccessAttribute(QualType& CurType,
4389                                             const AttributeList &Attr,
4390                                             Sema &S) {
4391  // Check the attribute arguments.
4392  if (Attr.getNumArgs() != 1) {
4393    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
4394    Attr.setInvalid();
4395    return;
4396  }
4397  Expr *sizeExpr = static_cast<Expr *>(Attr.getArg(0));
4398  llvm::APSInt arg(32);
4399  if (sizeExpr->isTypeDependent() || sizeExpr->isValueDependent() ||
4400      !sizeExpr->isIntegerConstantExpr(arg, S.Context)) {
4401    S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
4402      << "opencl_image_access" << sizeExpr->getSourceRange();
4403    Attr.setInvalid();
4404    return;
4405  }
4406  unsigned iarg = static_cast<unsigned>(arg.getZExtValue());
4407  switch (iarg) {
4408  case CLIA_read_only:
4409  case CLIA_write_only:
4410  case CLIA_read_write:
4411    // Implemented in a separate patch
4412    break;
4413  default:
4414    // Implemented in a separate patch
4415    S.Diag(Attr.getLoc(), diag::err_attribute_invalid_size)
4416      << sizeExpr->getSourceRange();
4417    Attr.setInvalid();
4418    break;
4419  }
4420}
4421
4422/// HandleVectorSizeAttribute - this attribute is only applicable to integral
4423/// and float scalars, although arrays, pointers, and function return values are
4424/// allowed in conjunction with this construct. Aggregates with this attribute
4425/// are invalid, even if they are of the same size as a corresponding scalar.
4426/// The raw attribute should contain precisely 1 argument, the vector size for
4427/// the variable, measured in bytes. If curType and rawAttr are well formed,
4428/// this routine will return a new vector type.
4429static void HandleVectorSizeAttr(QualType& CurType, const AttributeList &Attr,
4430                                 Sema &S) {
4431  // Check the attribute arguments.
4432  if (Attr.getNumArgs() != 1) {
4433    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
4434    Attr.setInvalid();
4435    return;
4436  }
4437  Expr *sizeExpr = static_cast<Expr *>(Attr.getArg(0));
4438  llvm::APSInt vecSize(32);
4439  if (sizeExpr->isTypeDependent() || sizeExpr->isValueDependent() ||
4440      !sizeExpr->isIntegerConstantExpr(vecSize, S.Context)) {
4441    S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
4442      << "vector_size" << sizeExpr->getSourceRange();
4443    Attr.setInvalid();
4444    return;
4445  }
4446  // the base type must be integer or float, and can't already be a vector.
4447  if (!CurType->isIntegerType() && !CurType->isRealFloatingType()) {
4448    S.Diag(Attr.getLoc(), diag::err_attribute_invalid_vector_type) << CurType;
4449    Attr.setInvalid();
4450    return;
4451  }
4452  unsigned typeSize = static_cast<unsigned>(S.Context.getTypeSize(CurType));
4453  // vecSize is specified in bytes - convert to bits.
4454  unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue() * 8);
4455
4456  // the vector size needs to be an integral multiple of the type size.
4457  if (vectorSize % typeSize) {
4458    S.Diag(Attr.getLoc(), diag::err_attribute_invalid_size)
4459      << sizeExpr->getSourceRange();
4460    Attr.setInvalid();
4461    return;
4462  }
4463  if (vectorSize == 0) {
4464    S.Diag(Attr.getLoc(), diag::err_attribute_zero_size)
4465      << sizeExpr->getSourceRange();
4466    Attr.setInvalid();
4467    return;
4468  }
4469
4470  // Success! Instantiate the vector type, the number of elements is > 0, and
4471  // not required to be a power of 2, unlike GCC.
4472  CurType = S.Context.getVectorType(CurType, vectorSize/typeSize,
4473                                    VectorType::GenericVector);
4474}
4475
4476/// \brief Process the OpenCL-like ext_vector_type attribute when it occurs on
4477/// a type.
4478static void HandleExtVectorTypeAttr(QualType &CurType,
4479                                    const AttributeList &Attr,
4480                                    Sema &S) {
4481  Expr *sizeExpr;
4482
4483  // Special case where the argument is a template id.
4484  if (Attr.getParameterName()) {
4485    CXXScopeSpec SS;
4486    SourceLocation TemplateKWLoc;
4487    UnqualifiedId id;
4488    id.setIdentifier(Attr.getParameterName(), Attr.getLoc());
4489
4490    ExprResult Size = S.ActOnIdExpression(S.getCurScope(), SS, TemplateKWLoc,
4491                                          id, false, false);
4492    if (Size.isInvalid())
4493      return;
4494
4495    sizeExpr = Size.get();
4496  } else {
4497    // check the attribute arguments.
4498    if (Attr.getNumArgs() != 1) {
4499      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
4500      return;
4501    }
4502    sizeExpr = Attr.getArg(0);
4503  }
4504
4505  // Create the vector type.
4506  QualType T = S.BuildExtVectorType(CurType, sizeExpr, Attr.getLoc());
4507  if (!T.isNull())
4508    CurType = T;
4509}
4510
4511/// HandleNeonVectorTypeAttr - The "neon_vector_type" and
4512/// "neon_polyvector_type" attributes are used to create vector types that
4513/// are mangled according to ARM's ABI.  Otherwise, these types are identical
4514/// to those created with the "vector_size" attribute.  Unlike "vector_size"
4515/// the argument to these Neon attributes is the number of vector elements,
4516/// not the vector size in bytes.  The vector width and element type must
4517/// match one of the standard Neon vector types.
4518static void HandleNeonVectorTypeAttr(QualType& CurType,
4519                                     const AttributeList &Attr, Sema &S,
4520                                     VectorType::VectorKind VecKind,
4521                                     const char *AttrName) {
4522  // Check the attribute arguments.
4523  if (Attr.getNumArgs() != 1) {
4524    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
4525    Attr.setInvalid();
4526    return;
4527  }
4528  // The number of elements must be an ICE.
4529  Expr *numEltsExpr = static_cast<Expr *>(Attr.getArg(0));
4530  llvm::APSInt numEltsInt(32);
4531  if (numEltsExpr->isTypeDependent() || numEltsExpr->isValueDependent() ||
4532      !numEltsExpr->isIntegerConstantExpr(numEltsInt, S.Context)) {
4533    S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
4534      << AttrName << numEltsExpr->getSourceRange();
4535    Attr.setInvalid();
4536    return;
4537  }
4538  // Only certain element types are supported for Neon vectors.
4539  const BuiltinType* BTy = CurType->getAs<BuiltinType>();
4540  if (!BTy ||
4541      (VecKind == VectorType::NeonPolyVector &&
4542       BTy->getKind() != BuiltinType::SChar &&
4543       BTy->getKind() != BuiltinType::Short) ||
4544      (BTy->getKind() != BuiltinType::SChar &&
4545       BTy->getKind() != BuiltinType::UChar &&
4546       BTy->getKind() != BuiltinType::Short &&
4547       BTy->getKind() != BuiltinType::UShort &&
4548       BTy->getKind() != BuiltinType::Int &&
4549       BTy->getKind() != BuiltinType::UInt &&
4550       BTy->getKind() != BuiltinType::LongLong &&
4551       BTy->getKind() != BuiltinType::ULongLong &&
4552       BTy->getKind() != BuiltinType::Float)) {
4553    S.Diag(Attr.getLoc(), diag::err_attribute_invalid_vector_type) <<CurType;
4554    Attr.setInvalid();
4555    return;
4556  }
4557  // The total size of the vector must be 64 or 128 bits.
4558  unsigned typeSize = static_cast<unsigned>(S.Context.getTypeSize(CurType));
4559  unsigned numElts = static_cast<unsigned>(numEltsInt.getZExtValue());
4560  unsigned vecSize = typeSize * numElts;
4561  if (vecSize != 64 && vecSize != 128) {
4562    S.Diag(Attr.getLoc(), diag::err_attribute_bad_neon_vector_size) << CurType;
4563    Attr.setInvalid();
4564    return;
4565  }
4566
4567  CurType = S.Context.getVectorType(CurType, numElts, VecKind);
4568}
4569
4570static void processTypeAttrs(TypeProcessingState &state, QualType &type,
4571                             TypeAttrLocation TAL, AttributeList *attrs) {
4572  // Scan through and apply attributes to this type where it makes sense.  Some
4573  // attributes (such as __address_space__, __vector_size__, etc) apply to the
4574  // type, but others can be present in the type specifiers even though they
4575  // apply to the decl.  Here we apply type attributes and ignore the rest.
4576
4577  AttributeList *next;
4578  do {
4579    AttributeList &attr = *attrs;
4580    next = attr.getNext();
4581
4582    // Skip attributes that were marked to be invalid.
4583    if (attr.isInvalid())
4584      continue;
4585
4586    if (attr.isCXX11Attribute()) {
4587      // [[gnu::...]] attributes are treated as declaration attributes, so may
4588      // not appertain to a DeclaratorChunk, even if we handle them as type
4589      // attributes.
4590      if (attr.getScopeName() && attr.getScopeName()->isStr("gnu")) {
4591        if (TAL == TAL_DeclChunk) {
4592          state.getSema().Diag(attr.getLoc(),
4593                               diag::warn_cxx11_gnu_attribute_on_type)
4594              << attr.getName();
4595          continue;
4596        }
4597      } else if (TAL != TAL_DeclChunk) {
4598        // Otherwise, only consider type processing for a C++11 attribute if
4599        // it's actually been applied to a type.
4600        continue;
4601      }
4602    }
4603
4604    // If this is an attribute we can handle, do so now,
4605    // otherwise, add it to the FnAttrs list for rechaining.
4606    switch (attr.getKind()) {
4607    default:
4608      // A C++11 attribute on a declarator chunk must appertain to a type.
4609      if (attr.isCXX11Attribute() && TAL == TAL_DeclChunk) {
4610        state.getSema().Diag(attr.getLoc(), diag::err_attribute_not_type_attr)
4611          << attr.getName();
4612        attr.setUsedAsTypeAttr();
4613      }
4614      break;
4615
4616    case AttributeList::UnknownAttribute:
4617      if (attr.isCXX11Attribute() && TAL == TAL_DeclChunk)
4618        state.getSema().Diag(attr.getLoc(),
4619                             diag::warn_unknown_attribute_ignored)
4620          << attr.getName();
4621      break;
4622
4623    case AttributeList::IgnoredAttribute:
4624      break;
4625
4626    case AttributeList::AT_MayAlias:
4627      // FIXME: This attribute needs to actually be handled, but if we ignore
4628      // it it breaks large amounts of Linux software.
4629      attr.setUsedAsTypeAttr();
4630      break;
4631    case AttributeList::AT_AddressSpace:
4632      HandleAddressSpaceTypeAttribute(type, attr, state.getSema());
4633      attr.setUsedAsTypeAttr();
4634      break;
4635    OBJC_POINTER_TYPE_ATTRS_CASELIST:
4636      if (!handleObjCPointerTypeAttr(state, attr, type))
4637        distributeObjCPointerTypeAttr(state, attr, type);
4638      attr.setUsedAsTypeAttr();
4639      break;
4640    case AttributeList::AT_VectorSize:
4641      HandleVectorSizeAttr(type, attr, state.getSema());
4642      attr.setUsedAsTypeAttr();
4643      break;
4644    case AttributeList::AT_ExtVectorType:
4645      HandleExtVectorTypeAttr(type, attr, state.getSema());
4646      attr.setUsedAsTypeAttr();
4647      break;
4648    case AttributeList::AT_NeonVectorType:
4649      HandleNeonVectorTypeAttr(type, attr, state.getSema(),
4650                               VectorType::NeonVector, "neon_vector_type");
4651      attr.setUsedAsTypeAttr();
4652      break;
4653    case AttributeList::AT_NeonPolyVectorType:
4654      HandleNeonVectorTypeAttr(type, attr, state.getSema(),
4655                               VectorType::NeonPolyVector,
4656                               "neon_polyvector_type");
4657      attr.setUsedAsTypeAttr();
4658      break;
4659    case AttributeList::AT_OpenCLImageAccess:
4660      HandleOpenCLImageAccessAttribute(type, attr, state.getSema());
4661      attr.setUsedAsTypeAttr();
4662      break;
4663
4664    case AttributeList::AT_Win64:
4665      attr.setUsedAsTypeAttr();
4666      break;
4667    MS_TYPE_ATTRS_CASELIST:
4668      if (!handleMSPointerTypeQualifierAttr(state, attr, type))
4669        attr.setUsedAsTypeAttr();
4670      break;
4671
4672    case AttributeList::AT_NSReturnsRetained:
4673      if (!state.getSema().getLangOpts().ObjCAutoRefCount)
4674        break;
4675      // fallthrough into the function attrs
4676
4677    FUNCTION_TYPE_ATTRS_CASELIST:
4678      attr.setUsedAsTypeAttr();
4679
4680      // Never process function type attributes as part of the
4681      // declaration-specifiers.
4682      if (TAL == TAL_DeclSpec)
4683        distributeFunctionTypeAttrFromDeclSpec(state, attr, type);
4684
4685      // Otherwise, handle the possible delays.
4686      else if (!handleFunctionTypeAttr(state, attr, type))
4687        distributeFunctionTypeAttr(state, attr, type);
4688      break;
4689    }
4690  } while ((attrs = next));
4691}
4692
4693/// \brief Ensure that the type of the given expression is complete.
4694///
4695/// This routine checks whether the expression \p E has a complete type. If the
4696/// expression refers to an instantiable construct, that instantiation is
4697/// performed as needed to complete its type. Furthermore
4698/// Sema::RequireCompleteType is called for the expression's type (or in the
4699/// case of a reference type, the referred-to type).
4700///
4701/// \param E The expression whose type is required to be complete.
4702/// \param Diagnoser The object that will emit a diagnostic if the type is
4703/// incomplete.
4704///
4705/// \returns \c true if the type of \p E is incomplete and diagnosed, \c false
4706/// otherwise.
4707bool Sema::RequireCompleteExprType(Expr *E, TypeDiagnoser &Diagnoser){
4708  QualType T = E->getType();
4709
4710  // Fast path the case where the type is already complete.
4711  if (!T->isIncompleteType())
4712    return false;
4713
4714  // Incomplete array types may be completed by the initializer attached to
4715  // their definitions. For static data members of class templates we need to
4716  // instantiate the definition to get this initializer and complete the type.
4717  if (T->isIncompleteArrayType()) {
4718    if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParens())) {
4719      if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
4720        if (Var->isStaticDataMember() &&
4721            Var->getInstantiatedFromStaticDataMember()) {
4722
4723          MemberSpecializationInfo *MSInfo = Var->getMemberSpecializationInfo();
4724          assert(MSInfo && "Missing member specialization information?");
4725          if (MSInfo->getTemplateSpecializationKind()
4726                != TSK_ExplicitSpecialization) {
4727            // If we don't already have a point of instantiation, this is it.
4728            if (MSInfo->getPointOfInstantiation().isInvalid()) {
4729              MSInfo->setPointOfInstantiation(E->getLocStart());
4730
4731              // This is a modification of an existing AST node. Notify
4732              // listeners.
4733              if (ASTMutationListener *L = getASTMutationListener())
4734                L->StaticDataMemberInstantiated(Var);
4735            }
4736
4737            InstantiateStaticDataMemberDefinition(E->getExprLoc(), Var);
4738
4739            // Update the type to the newly instantiated definition's type both
4740            // here and within the expression.
4741            if (VarDecl *Def = Var->getDefinition()) {
4742              DRE->setDecl(Def);
4743              T = Def->getType();
4744              DRE->setType(T);
4745              E->setType(T);
4746            }
4747          }
4748
4749          // We still go on to try to complete the type independently, as it
4750          // may also require instantiations or diagnostics if it remains
4751          // incomplete.
4752        }
4753      }
4754    }
4755  }
4756
4757  // FIXME: Are there other cases which require instantiating something other
4758  // than the type to complete the type of an expression?
4759
4760  // Look through reference types and complete the referred type.
4761  if (const ReferenceType *Ref = T->getAs<ReferenceType>())
4762    T = Ref->getPointeeType();
4763
4764  return RequireCompleteType(E->getExprLoc(), T, Diagnoser);
4765}
4766
4767namespace {
4768  struct TypeDiagnoserDiag : Sema::TypeDiagnoser {
4769    unsigned DiagID;
4770
4771    TypeDiagnoserDiag(unsigned DiagID)
4772      : Sema::TypeDiagnoser(DiagID == 0), DiagID(DiagID) {}
4773
4774    virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) {
4775      if (Suppressed) return;
4776      S.Diag(Loc, DiagID) << T;
4777    }
4778  };
4779}
4780
4781bool Sema::RequireCompleteExprType(Expr *E, unsigned DiagID) {
4782  TypeDiagnoserDiag Diagnoser(DiagID);
4783  return RequireCompleteExprType(E, Diagnoser);
4784}
4785
4786/// @brief Ensure that the type T is a complete type.
4787///
4788/// This routine checks whether the type @p T is complete in any
4789/// context where a complete type is required. If @p T is a complete
4790/// type, returns false. If @p T is a class template specialization,
4791/// this routine then attempts to perform class template
4792/// instantiation. If instantiation fails, or if @p T is incomplete
4793/// and cannot be completed, issues the diagnostic @p diag (giving it
4794/// the type @p T) and returns true.
4795///
4796/// @param Loc  The location in the source that the incomplete type
4797/// diagnostic should refer to.
4798///
4799/// @param T  The type that this routine is examining for completeness.
4800///
4801/// @returns @c true if @p T is incomplete and a diagnostic was emitted,
4802/// @c false otherwise.
4803bool Sema::RequireCompleteType(SourceLocation Loc, QualType T,
4804                               TypeDiagnoser &Diagnoser) {
4805  // FIXME: Add this assertion to make sure we always get instantiation points.
4806  //  assert(!Loc.isInvalid() && "Invalid location in RequireCompleteType");
4807  // FIXME: Add this assertion to help us flush out problems with
4808  // checking for dependent types and type-dependent expressions.
4809  //
4810  //  assert(!T->isDependentType() &&
4811  //         "Can't ask whether a dependent type is complete");
4812
4813  // If we have a complete type, we're done.
4814  NamedDecl *Def = 0;
4815  if (!T->isIncompleteType(&Def)) {
4816    // If we know about the definition but it is not visible, complain.
4817    if (!Diagnoser.Suppressed && Def && !LookupResult::isVisible(Def)) {
4818      // Suppress this error outside of a SFINAE context if we've already
4819      // emitted the error once for this type. There's no usefulness in
4820      // repeating the diagnostic.
4821      // FIXME: Add a Fix-It that imports the corresponding module or includes
4822      // the header.
4823      Module *Owner = Def->getOwningModule();
4824      Diag(Loc, diag::err_module_private_definition)
4825        << T << Owner->getFullModuleName();
4826      Diag(Def->getLocation(), diag::note_previous_definition);
4827
4828      if (!isSFINAEContext()) {
4829        // Recover by implicitly importing this module.
4830        createImplicitModuleImport(Loc, Owner);
4831      }
4832    }
4833
4834    return false;
4835  }
4836
4837  const TagType *Tag = T->getAs<TagType>();
4838  const ObjCInterfaceType *IFace = 0;
4839
4840  if (Tag) {
4841    // Avoid diagnosing invalid decls as incomplete.
4842    if (Tag->getDecl()->isInvalidDecl())
4843      return true;
4844
4845    // Give the external AST source a chance to complete the type.
4846    if (Tag->getDecl()->hasExternalLexicalStorage()) {
4847      Context.getExternalSource()->CompleteType(Tag->getDecl());
4848      if (!Tag->isIncompleteType())
4849        return false;
4850    }
4851  }
4852  else if ((IFace = T->getAs<ObjCInterfaceType>())) {
4853    // Avoid diagnosing invalid decls as incomplete.
4854    if (IFace->getDecl()->isInvalidDecl())
4855      return true;
4856
4857    // Give the external AST source a chance to complete the type.
4858    if (IFace->getDecl()->hasExternalLexicalStorage()) {
4859      Context.getExternalSource()->CompleteType(IFace->getDecl());
4860      if (!IFace->isIncompleteType())
4861        return false;
4862    }
4863  }
4864
4865  // If we have a class template specialization or a class member of a
4866  // class template specialization, or an array with known size of such,
4867  // try to instantiate it.
4868  QualType MaybeTemplate = T;
4869  while (const ConstantArrayType *Array
4870           = Context.getAsConstantArrayType(MaybeTemplate))
4871    MaybeTemplate = Array->getElementType();
4872  if (const RecordType *Record = MaybeTemplate->getAs<RecordType>()) {
4873    if (ClassTemplateSpecializationDecl *ClassTemplateSpec
4874          = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
4875      if (ClassTemplateSpec->getSpecializationKind() == TSK_Undeclared)
4876        return InstantiateClassTemplateSpecialization(Loc, ClassTemplateSpec,
4877                                                      TSK_ImplicitInstantiation,
4878                                            /*Complain=*/!Diagnoser.Suppressed);
4879    } else if (CXXRecordDecl *Rec
4880                 = dyn_cast<CXXRecordDecl>(Record->getDecl())) {
4881      CXXRecordDecl *Pattern = Rec->getInstantiatedFromMemberClass();
4882      if (!Rec->isBeingDefined() && Pattern) {
4883        MemberSpecializationInfo *MSI = Rec->getMemberSpecializationInfo();
4884        assert(MSI && "Missing member specialization information?");
4885        // This record was instantiated from a class within a template.
4886        if (MSI->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
4887          return InstantiateClass(Loc, Rec, Pattern,
4888                                  getTemplateInstantiationArgs(Rec),
4889                                  TSK_ImplicitInstantiation,
4890                                  /*Complain=*/!Diagnoser.Suppressed);
4891      }
4892    }
4893  }
4894
4895  if (Diagnoser.Suppressed)
4896    return true;
4897
4898  // We have an incomplete type. Produce a diagnostic.
4899  Diagnoser.diagnose(*this, Loc, T);
4900
4901  // If the type was a forward declaration of a class/struct/union
4902  // type, produce a note.
4903  if (Tag && !Tag->getDecl()->isInvalidDecl())
4904    Diag(Tag->getDecl()->getLocation(),
4905         Tag->isBeingDefined() ? diag::note_type_being_defined
4906                               : diag::note_forward_declaration)
4907      << QualType(Tag, 0);
4908
4909  // If the Objective-C class was a forward declaration, produce a note.
4910  if (IFace && !IFace->getDecl()->isInvalidDecl())
4911    Diag(IFace->getDecl()->getLocation(), diag::note_forward_class);
4912
4913  return true;
4914}
4915
4916bool Sema::RequireCompleteType(SourceLocation Loc, QualType T,
4917                               unsigned DiagID) {
4918  TypeDiagnoserDiag Diagnoser(DiagID);
4919  return RequireCompleteType(Loc, T, Diagnoser);
4920}
4921
4922/// \brief Get diagnostic %select index for tag kind for
4923/// literal type diagnostic message.
4924/// WARNING: Indexes apply to particular diagnostics only!
4925///
4926/// \returns diagnostic %select index.
4927static unsigned getLiteralDiagFromTagKind(TagTypeKind Tag) {
4928  switch (Tag) {
4929  case TTK_Struct: return 0;
4930  case TTK_Interface: return 1;
4931  case TTK_Class:  return 2;
4932  default: llvm_unreachable("Invalid tag kind for literal type diagnostic!");
4933  }
4934}
4935
4936/// @brief Ensure that the type T is a literal type.
4937///
4938/// This routine checks whether the type @p T is a literal type. If @p T is an
4939/// incomplete type, an attempt is made to complete it. If @p T is a literal
4940/// type, or @p AllowIncompleteType is true and @p T is an incomplete type,
4941/// returns false. Otherwise, this routine issues the diagnostic @p PD (giving
4942/// it the type @p T), along with notes explaining why the type is not a
4943/// literal type, and returns true.
4944///
4945/// @param Loc  The location in the source that the non-literal type
4946/// diagnostic should refer to.
4947///
4948/// @param T  The type that this routine is examining for literalness.
4949///
4950/// @param Diagnoser Emits a diagnostic if T is not a literal type.
4951///
4952/// @returns @c true if @p T is not a literal type and a diagnostic was emitted,
4953/// @c false otherwise.
4954bool Sema::RequireLiteralType(SourceLocation Loc, QualType T,
4955                              TypeDiagnoser &Diagnoser) {
4956  assert(!T->isDependentType() && "type should not be dependent");
4957
4958  QualType ElemType = Context.getBaseElementType(T);
4959  RequireCompleteType(Loc, ElemType, 0);
4960
4961  if (T->isLiteralType(Context))
4962    return false;
4963
4964  if (Diagnoser.Suppressed)
4965    return true;
4966
4967  Diagnoser.diagnose(*this, Loc, T);
4968
4969  if (T->isVariableArrayType())
4970    return true;
4971
4972  const RecordType *RT = ElemType->getAs<RecordType>();
4973  if (!RT)
4974    return true;
4975
4976  const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4977
4978  // A partially-defined class type can't be a literal type, because a literal
4979  // class type must have a trivial destructor (which can't be checked until
4980  // the class definition is complete).
4981  if (!RD->isCompleteDefinition()) {
4982    RequireCompleteType(Loc, ElemType, diag::note_non_literal_incomplete, T);
4983    return true;
4984  }
4985
4986  // If the class has virtual base classes, then it's not an aggregate, and
4987  // cannot have any constexpr constructors or a trivial default constructor,
4988  // so is non-literal. This is better to diagnose than the resulting absence
4989  // of constexpr constructors.
4990  if (RD->getNumVBases()) {
4991    Diag(RD->getLocation(), diag::note_non_literal_virtual_base)
4992      << getLiteralDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
4993    for (CXXRecordDecl::base_class_const_iterator I = RD->vbases_begin(),
4994           E = RD->vbases_end(); I != E; ++I)
4995      Diag(I->getLocStart(),
4996           diag::note_constexpr_virtual_base_here) << I->getSourceRange();
4997  } else if (!RD->isAggregate() && !RD->hasConstexprNonCopyMoveConstructor() &&
4998             !RD->hasTrivialDefaultConstructor()) {
4999    Diag(RD->getLocation(), diag::note_non_literal_no_constexpr_ctors) << RD;
5000  } else if (RD->hasNonLiteralTypeFieldsOrBases()) {
5001    for (CXXRecordDecl::base_class_const_iterator I = RD->bases_begin(),
5002         E = RD->bases_end(); I != E; ++I) {
5003      if (!I->getType()->isLiteralType(Context)) {
5004        Diag(I->getLocStart(),
5005             diag::note_non_literal_base_class)
5006          << RD << I->getType() << I->getSourceRange();
5007        return true;
5008      }
5009    }
5010    for (CXXRecordDecl::field_iterator I = RD->field_begin(),
5011         E = RD->field_end(); I != E; ++I) {
5012      if (!I->getType()->isLiteralType(Context) ||
5013          I->getType().isVolatileQualified()) {
5014        Diag(I->getLocation(), diag::note_non_literal_field)
5015          << RD << *I << I->getType()
5016          << I->getType().isVolatileQualified();
5017        return true;
5018      }
5019    }
5020  } else if (!RD->hasTrivialDestructor()) {
5021    // All fields and bases are of literal types, so have trivial destructors.
5022    // If this class's destructor is non-trivial it must be user-declared.
5023    CXXDestructorDecl *Dtor = RD->getDestructor();
5024    assert(Dtor && "class has literal fields and bases but no dtor?");
5025    if (!Dtor)
5026      return true;
5027
5028    Diag(Dtor->getLocation(), Dtor->isUserProvided() ?
5029         diag::note_non_literal_user_provided_dtor :
5030         diag::note_non_literal_nontrivial_dtor) << RD;
5031    if (!Dtor->isUserProvided())
5032      SpecialMemberIsTrivial(Dtor, CXXDestructor, /*Diagnose*/true);
5033  }
5034
5035  return true;
5036}
5037
5038bool Sema::RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID) {
5039  TypeDiagnoserDiag Diagnoser(DiagID);
5040  return RequireLiteralType(Loc, T, Diagnoser);
5041}
5042
5043/// \brief Retrieve a version of the type 'T' that is elaborated by Keyword
5044/// and qualified by the nested-name-specifier contained in SS.
5045QualType Sema::getElaboratedType(ElaboratedTypeKeyword Keyword,
5046                                 const CXXScopeSpec &SS, QualType T) {
5047  if (T.isNull())
5048    return T;
5049  NestedNameSpecifier *NNS;
5050  if (SS.isValid())
5051    NNS = static_cast<NestedNameSpecifier *>(SS.getScopeRep());
5052  else {
5053    if (Keyword == ETK_None)
5054      return T;
5055    NNS = 0;
5056  }
5057  return Context.getElaboratedType(Keyword, NNS, T);
5058}
5059
5060QualType Sema::BuildTypeofExprType(Expr *E, SourceLocation Loc) {
5061  ExprResult ER = CheckPlaceholderExpr(E);
5062  if (ER.isInvalid()) return QualType();
5063  E = ER.take();
5064
5065  if (!E->isTypeDependent()) {
5066    QualType T = E->getType();
5067    if (const TagType *TT = T->getAs<TagType>())
5068      DiagnoseUseOfDecl(TT->getDecl(), E->getExprLoc());
5069  }
5070  return Context.getTypeOfExprType(E);
5071}
5072
5073/// getDecltypeForExpr - Given an expr, will return the decltype for
5074/// that expression, according to the rules in C++11
5075/// [dcl.type.simple]p4 and C++11 [expr.lambda.prim]p18.
5076static QualType getDecltypeForExpr(Sema &S, Expr *E) {
5077  if (E->isTypeDependent())
5078    return S.Context.DependentTy;
5079
5080  // C++11 [dcl.type.simple]p4:
5081  //   The type denoted by decltype(e) is defined as follows:
5082  //
5083  //     - if e is an unparenthesized id-expression or an unparenthesized class
5084  //       member access (5.2.5), decltype(e) is the type of the entity named
5085  //       by e. If there is no such entity, or if e names a set of overloaded
5086  //       functions, the program is ill-formed;
5087  //
5088  // We apply the same rules for Objective-C ivar and property references.
5089  if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
5090    if (const ValueDecl *VD = dyn_cast<ValueDecl>(DRE->getDecl()))
5091      return VD->getType();
5092  } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
5093    if (const FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
5094      return FD->getType();
5095  } else if (const ObjCIvarRefExpr *IR = dyn_cast<ObjCIvarRefExpr>(E)) {
5096    return IR->getDecl()->getType();
5097  } else if (const ObjCPropertyRefExpr *PR = dyn_cast<ObjCPropertyRefExpr>(E)) {
5098    if (PR->isExplicitProperty())
5099      return PR->getExplicitProperty()->getType();
5100  }
5101
5102  // C++11 [expr.lambda.prim]p18:
5103  //   Every occurrence of decltype((x)) where x is a possibly
5104  //   parenthesized id-expression that names an entity of automatic
5105  //   storage duration is treated as if x were transformed into an
5106  //   access to a corresponding data member of the closure type that
5107  //   would have been declared if x were an odr-use of the denoted
5108  //   entity.
5109  using namespace sema;
5110  if (S.getCurLambda()) {
5111    if (isa<ParenExpr>(E)) {
5112      if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParens())) {
5113        if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
5114          QualType T = S.getCapturedDeclRefType(Var, DRE->getLocation());
5115          if (!T.isNull())
5116            return S.Context.getLValueReferenceType(T);
5117        }
5118      }
5119    }
5120  }
5121
5122
5123  // C++11 [dcl.type.simple]p4:
5124  //   [...]
5125  QualType T = E->getType();
5126  switch (E->getValueKind()) {
5127  //     - otherwise, if e is an xvalue, decltype(e) is T&&, where T is the
5128  //       type of e;
5129  case VK_XValue: T = S.Context.getRValueReferenceType(T); break;
5130  //     - otherwise, if e is an lvalue, decltype(e) is T&, where T is the
5131  //       type of e;
5132  case VK_LValue: T = S.Context.getLValueReferenceType(T); break;
5133  //  - otherwise, decltype(e) is the type of e.
5134  case VK_RValue: break;
5135  }
5136
5137  return T;
5138}
5139
5140QualType Sema::BuildDecltypeType(Expr *E, SourceLocation Loc) {
5141  ExprResult ER = CheckPlaceholderExpr(E);
5142  if (ER.isInvalid()) return QualType();
5143  E = ER.take();
5144
5145  return Context.getDecltypeType(E, getDecltypeForExpr(*this, E));
5146}
5147
5148QualType Sema::BuildUnaryTransformType(QualType BaseType,
5149                                       UnaryTransformType::UTTKind UKind,
5150                                       SourceLocation Loc) {
5151  switch (UKind) {
5152  case UnaryTransformType::EnumUnderlyingType:
5153    if (!BaseType->isDependentType() && !BaseType->isEnumeralType()) {
5154      Diag(Loc, diag::err_only_enums_have_underlying_types);
5155      return QualType();
5156    } else {
5157      QualType Underlying = BaseType;
5158      if (!BaseType->isDependentType()) {
5159        EnumDecl *ED = BaseType->getAs<EnumType>()->getDecl();
5160        assert(ED && "EnumType has no EnumDecl");
5161        DiagnoseUseOfDecl(ED, Loc);
5162        Underlying = ED->getIntegerType();
5163      }
5164      assert(!Underlying.isNull());
5165      return Context.getUnaryTransformType(BaseType, Underlying,
5166                                        UnaryTransformType::EnumUnderlyingType);
5167    }
5168  }
5169  llvm_unreachable("unknown unary transform type");
5170}
5171
5172QualType Sema::BuildAtomicType(QualType T, SourceLocation Loc) {
5173  if (!T->isDependentType()) {
5174    // FIXME: It isn't entirely clear whether incomplete atomic types
5175    // are allowed or not; for simplicity, ban them for the moment.
5176    if (RequireCompleteType(Loc, T, diag::err_atomic_specifier_bad_type, 0))
5177      return QualType();
5178
5179    int DisallowedKind = -1;
5180    if (T->isArrayType())
5181      DisallowedKind = 1;
5182    else if (T->isFunctionType())
5183      DisallowedKind = 2;
5184    else if (T->isReferenceType())
5185      DisallowedKind = 3;
5186    else if (T->isAtomicType())
5187      DisallowedKind = 4;
5188    else if (T.hasQualifiers())
5189      DisallowedKind = 5;
5190    else if (!T.isTriviallyCopyableType(Context))
5191      // Some other non-trivially-copyable type (probably a C++ class)
5192      DisallowedKind = 6;
5193
5194    if (DisallowedKind != -1) {
5195      Diag(Loc, diag::err_atomic_specifier_bad_type) << DisallowedKind << T;
5196      return QualType();
5197    }
5198
5199    // FIXME: Do we need any handling for ARC here?
5200  }
5201
5202  // Build the pointer type.
5203  return Context.getAtomicType(T);
5204}
5205