clang  9.0.0svn
SemaType.cpp
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1 //===--- SemaType.cpp - Semantic Analysis for Types -----------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements type-related semantic analysis.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "TypeLocBuilder.h"
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/DeclObjC.h"
20 #include "clang/AST/DeclTemplate.h"
21 #include "clang/AST/Expr.h"
22 #include "clang/AST/TypeLoc.h"
25 #include "clang/Basic/TargetInfo.h"
26 #include "clang/Lex/Preprocessor.h"
27 #include "clang/Sema/DeclSpec.h"
29 #include "clang/Sema/Lookup.h"
30 #include "clang/Sema/ScopeInfo.h"
32 #include "clang/Sema/Template.h"
34 #include "llvm/ADT/SmallPtrSet.h"
35 #include "llvm/ADT/SmallString.h"
36 #include "llvm/ADT/StringSwitch.h"
37 #include "llvm/Support/ErrorHandling.h"
38 
39 using namespace clang;
40 
45 };
46 
47 /// isOmittedBlockReturnType - Return true if this declarator is missing a
48 /// return type because this is a omitted return type on a block literal.
49 static bool isOmittedBlockReturnType(const Declarator &D) {
52  return false;
53 
54  if (D.getNumTypeObjects() == 0)
55  return true; // ^{ ... }
56 
57  if (D.getNumTypeObjects() == 1 &&
59  return true; // ^(int X, float Y) { ... }
60 
61  return false;
62 }
63 
64 /// diagnoseBadTypeAttribute - Diagnoses a type attribute which
65 /// doesn't apply to the given type.
66 static void diagnoseBadTypeAttribute(Sema &S, const ParsedAttr &attr,
67  QualType type) {
68  TypeDiagSelector WhichType;
69  bool useExpansionLoc = true;
70  switch (attr.getKind()) {
71  case ParsedAttr::AT_ObjCGC:
72  WhichType = TDS_Pointer;
73  break;
74  case ParsedAttr::AT_ObjCOwnership:
75  WhichType = TDS_ObjCObjOrBlock;
76  break;
77  default:
78  // Assume everything else was a function attribute.
79  WhichType = TDS_Function;
80  useExpansionLoc = false;
81  break;
82  }
83 
84  SourceLocation loc = attr.getLoc();
85  StringRef name = attr.getName()->getName();
86 
87  // The GC attributes are usually written with macros; special-case them.
88  IdentifierInfo *II = attr.isArgIdent(0) ? attr.getArgAsIdent(0)->Ident
89  : nullptr;
90  if (useExpansionLoc && loc.isMacroID() && II) {
91  if (II->isStr("strong")) {
92  if (S.findMacroSpelling(loc, "__strong")) name = "__strong";
93  } else if (II->isStr("weak")) {
94  if (S.findMacroSpelling(loc, "__weak")) name = "__weak";
95  }
96  }
97 
98  S.Diag(loc, diag::warn_type_attribute_wrong_type) << name << WhichType
99  << type;
100 }
101 
102 // objc_gc applies to Objective-C pointers or, otherwise, to the
103 // smallest available pointer type (i.e. 'void*' in 'void**').
104 #define OBJC_POINTER_TYPE_ATTRS_CASELIST \
105  case ParsedAttr::AT_ObjCGC: \
106  case ParsedAttr::AT_ObjCOwnership
107 
108 // Calling convention attributes.
109 #define CALLING_CONV_ATTRS_CASELIST \
110  case ParsedAttr::AT_CDecl: \
111  case ParsedAttr::AT_FastCall: \
112  case ParsedAttr::AT_StdCall: \
113  case ParsedAttr::AT_ThisCall: \
114  case ParsedAttr::AT_RegCall: \
115  case ParsedAttr::AT_Pascal: \
116  case ParsedAttr::AT_SwiftCall: \
117  case ParsedAttr::AT_VectorCall: \
118  case ParsedAttr::AT_AArch64VectorPcs: \
119  case ParsedAttr::AT_MSABI: \
120  case ParsedAttr::AT_SysVABI: \
121  case ParsedAttr::AT_Pcs: \
122  case ParsedAttr::AT_IntelOclBicc: \
123  case ParsedAttr::AT_PreserveMost: \
124  case ParsedAttr::AT_PreserveAll
125 
126 // Function type attributes.
127 #define FUNCTION_TYPE_ATTRS_CASELIST \
128  case ParsedAttr::AT_NSReturnsRetained: \
129  case ParsedAttr::AT_NoReturn: \
130  case ParsedAttr::AT_Regparm: \
131  case ParsedAttr::AT_AnyX86NoCallerSavedRegisters: \
132  case ParsedAttr::AT_AnyX86NoCfCheck: \
133  CALLING_CONV_ATTRS_CASELIST
134 
135 // Microsoft-specific type qualifiers.
136 #define MS_TYPE_ATTRS_CASELIST \
137  case ParsedAttr::AT_Ptr32: \
138  case ParsedAttr::AT_Ptr64: \
139  case ParsedAttr::AT_SPtr: \
140  case ParsedAttr::AT_UPtr
141 
142 // Nullability qualifiers.
143 #define NULLABILITY_TYPE_ATTRS_CASELIST \
144  case ParsedAttr::AT_TypeNonNull: \
145  case ParsedAttr::AT_TypeNullable: \
146  case ParsedAttr::AT_TypeNullUnspecified
147 
148 namespace {
149  /// An object which stores processing state for the entire
150  /// GetTypeForDeclarator process.
151  class TypeProcessingState {
152  Sema &sema;
153 
154  /// The declarator being processed.
155  Declarator &declarator;
156 
157  /// The index of the declarator chunk we're currently processing.
158  /// May be the total number of valid chunks, indicating the
159  /// DeclSpec.
160  unsigned chunkIndex;
161 
162  /// Whether there are non-trivial modifications to the decl spec.
163  bool trivial;
164 
165  /// Whether we saved the attributes in the decl spec.
166  bool hasSavedAttrs;
167 
168  /// The original set of attributes on the DeclSpec.
169  SmallVector<ParsedAttr *, 2> savedAttrs;
170 
171  /// A list of attributes to diagnose the uselessness of when the
172  /// processing is complete.
173  SmallVector<ParsedAttr *, 2> ignoredTypeAttrs;
174 
175  /// Attributes corresponding to AttributedTypeLocs that we have not yet
176  /// populated.
177  // FIXME: The two-phase mechanism by which we construct Types and fill
178  // their TypeLocs makes it hard to correctly assign these. We keep the
179  // attributes in creation order as an attempt to make them line up
180  // properly.
181  using TypeAttrPair = std::pair<const AttributedType*, const Attr*>;
182  SmallVector<TypeAttrPair, 8> AttrsForTypes;
183  bool AttrsForTypesSorted = true;
184 
185  /// Flag to indicate we parsed a noderef attribute. This is used for
186  /// validating that noderef was used on a pointer or array.
187  bool parsedNoDeref;
188 
189  public:
190  TypeProcessingState(Sema &sema, Declarator &declarator)
191  : sema(sema), declarator(declarator),
192  chunkIndex(declarator.getNumTypeObjects()), trivial(true),
193  hasSavedAttrs(false), parsedNoDeref(false) {}
194 
195  Sema &getSema() const {
196  return sema;
197  }
198 
199  Declarator &getDeclarator() const {
200  return declarator;
201  }
202 
203  bool isProcessingDeclSpec() const {
204  return chunkIndex == declarator.getNumTypeObjects();
205  }
206 
207  unsigned getCurrentChunkIndex() const {
208  return chunkIndex;
209  }
210 
211  void setCurrentChunkIndex(unsigned idx) {
212  assert(idx <= declarator.getNumTypeObjects());
213  chunkIndex = idx;
214  }
215 
216  ParsedAttributesView &getCurrentAttributes() const {
217  if (isProcessingDeclSpec())
218  return getMutableDeclSpec().getAttributes();
219  return declarator.getTypeObject(chunkIndex).getAttrs();
220  }
221 
222  /// Save the current set of attributes on the DeclSpec.
223  void saveDeclSpecAttrs() {
224  // Don't try to save them multiple times.
225  if (hasSavedAttrs) return;
226 
227  DeclSpec &spec = getMutableDeclSpec();
228  for (ParsedAttr &AL : spec.getAttributes())
229  savedAttrs.push_back(&AL);
230  trivial &= savedAttrs.empty();
231  hasSavedAttrs = true;
232  }
233 
234  /// Record that we had nowhere to put the given type attribute.
235  /// We will diagnose such attributes later.
236  void addIgnoredTypeAttr(ParsedAttr &attr) {
237  ignoredTypeAttrs.push_back(&attr);
238  }
239 
240  /// Diagnose all the ignored type attributes, given that the
241  /// declarator worked out to the given type.
242  void diagnoseIgnoredTypeAttrs(QualType type) const {
243  for (auto *Attr : ignoredTypeAttrs)
244  diagnoseBadTypeAttribute(getSema(), *Attr, type);
245  }
246 
247  /// Get an attributed type for the given attribute, and remember the Attr
248  /// object so that we can attach it to the AttributedTypeLoc.
249  QualType getAttributedType(Attr *A, QualType ModifiedType,
250  QualType EquivType) {
251  QualType T =
252  sema.Context.getAttributedType(A->getKind(), ModifiedType, EquivType);
253  AttrsForTypes.push_back({cast<AttributedType>(T.getTypePtr()), A});
254  AttrsForTypesSorted = false;
255  return T;
256  }
257 
258  /// Extract and remove the Attr* for a given attributed type.
259  const Attr *takeAttrForAttributedType(const AttributedType *AT) {
260  if (!AttrsForTypesSorted) {
261  std::stable_sort(AttrsForTypes.begin(), AttrsForTypes.end(),
262  [](const TypeAttrPair &A, const TypeAttrPair &B) {
263  return A.first < B.first;
264  });
265  AttrsForTypesSorted = true;
266  }
267 
268  // FIXME: This is quadratic if we have lots of reuses of the same
269  // attributed type.
270  for (auto It = std::partition_point(
271  AttrsForTypes.begin(), AttrsForTypes.end(),
272  [=](const TypeAttrPair &A) { return A.first < AT; });
273  It != AttrsForTypes.end() && It->first == AT; ++It) {
274  if (It->second) {
275  const Attr *Result = It->second;
276  It->second = nullptr;
277  return Result;
278  }
279  }
280 
281  llvm_unreachable("no Attr* for AttributedType*");
282  }
283 
284  void setParsedNoDeref(bool parsed) { parsedNoDeref = parsed; }
285 
286  bool didParseNoDeref() const { return parsedNoDeref; }
287 
288  ~TypeProcessingState() {
289  if (trivial) return;
290 
291  restoreDeclSpecAttrs();
292  }
293 
294  private:
295  DeclSpec &getMutableDeclSpec() const {
296  return const_cast<DeclSpec&>(declarator.getDeclSpec());
297  }
298 
299  void restoreDeclSpecAttrs() {
300  assert(hasSavedAttrs);
301 
302  getMutableDeclSpec().getAttributes().clearListOnly();
303  for (ParsedAttr *AL : savedAttrs)
304  getMutableDeclSpec().getAttributes().addAtEnd(AL);
305  }
306  };
307 } // end anonymous namespace
308 
310  ParsedAttributesView &fromList,
311  ParsedAttributesView &toList) {
312  fromList.remove(&attr);
313  toList.addAtEnd(&attr);
314 }
315 
316 /// The location of a type attribute.
318  /// The attribute is in the decl-specifier-seq.
320  /// The attribute is part of a DeclaratorChunk.
322  /// The attribute is immediately after the declaration's name.
324 };
325 
326 static void processTypeAttrs(TypeProcessingState &state, QualType &type,
328 
329 static bool handleFunctionTypeAttr(TypeProcessingState &state, ParsedAttr &attr,
330  QualType &type);
331 
332 static bool handleMSPointerTypeQualifierAttr(TypeProcessingState &state,
333  ParsedAttr &attr, QualType &type);
334 
335 static bool handleObjCGCTypeAttr(TypeProcessingState &state, ParsedAttr &attr,
336  QualType &type);
337 
338 static bool handleObjCOwnershipTypeAttr(TypeProcessingState &state,
339  ParsedAttr &attr, QualType &type);
340 
341 static bool handleObjCPointerTypeAttr(TypeProcessingState &state,
342  ParsedAttr &attr, QualType &type) {
343  if (attr.getKind() == ParsedAttr::AT_ObjCGC)
344  return handleObjCGCTypeAttr(state, attr, type);
345  assert(attr.getKind() == ParsedAttr::AT_ObjCOwnership);
346  return handleObjCOwnershipTypeAttr(state, attr, type);
347 }
348 
349 /// Given the index of a declarator chunk, check whether that chunk
350 /// directly specifies the return type of a function and, if so, find
351 /// an appropriate place for it.
352 ///
353 /// \param i - a notional index which the search will start
354 /// immediately inside
355 ///
356 /// \param onlyBlockPointers Whether we should only look into block
357 /// pointer types (vs. all pointer types).
359  unsigned i,
360  bool onlyBlockPointers) {
361  assert(i <= declarator.getNumTypeObjects());
362 
363  DeclaratorChunk *result = nullptr;
364 
365  // First, look inwards past parens for a function declarator.
366  for (; i != 0; --i) {
367  DeclaratorChunk &fnChunk = declarator.getTypeObject(i-1);
368  switch (fnChunk.Kind) {
370  continue;
371 
372  // If we find anything except a function, bail out.
379  return result;
380 
381  // If we do find a function declarator, scan inwards from that,
382  // looking for a (block-)pointer declarator.
384  for (--i; i != 0; --i) {
385  DeclaratorChunk &ptrChunk = declarator.getTypeObject(i-1);
386  switch (ptrChunk.Kind) {
392  continue;
393 
396  if (onlyBlockPointers)
397  continue;
398 
399  LLVM_FALLTHROUGH;
400 
402  result = &ptrChunk;
403  goto continue_outer;
404  }
405  llvm_unreachable("bad declarator chunk kind");
406  }
407 
408  // If we run out of declarators doing that, we're done.
409  return result;
410  }
411  llvm_unreachable("bad declarator chunk kind");
412 
413  // Okay, reconsider from our new point.
414  continue_outer: ;
415  }
416 
417  // Ran out of chunks, bail out.
418  return result;
419 }
420 
421 /// Given that an objc_gc attribute was written somewhere on a
422 /// declaration *other* than on the declarator itself (for which, use
423 /// distributeObjCPointerTypeAttrFromDeclarator), and given that it
424 /// didn't apply in whatever position it was written in, try to move
425 /// it to a more appropriate position.
426 static void distributeObjCPointerTypeAttr(TypeProcessingState &state,
427  ParsedAttr &attr, QualType type) {
428  Declarator &declarator = state.getDeclarator();
429 
430  // Move it to the outermost normal or block pointer declarator.
431  for (unsigned i = state.getCurrentChunkIndex(); i != 0; --i) {
432  DeclaratorChunk &chunk = declarator.getTypeObject(i-1);
433  switch (chunk.Kind) {
436  // But don't move an ARC ownership attribute to the return type
437  // of a block.
438  DeclaratorChunk *destChunk = nullptr;
439  if (state.isProcessingDeclSpec() &&
440  attr.getKind() == ParsedAttr::AT_ObjCOwnership)
441  destChunk = maybeMovePastReturnType(declarator, i - 1,
442  /*onlyBlockPointers=*/true);
443  if (!destChunk) destChunk = &chunk;
444 
445  moveAttrFromListToList(attr, state.getCurrentAttributes(),
446  destChunk->getAttrs());
447  return;
448  }
449 
452  continue;
453 
454  // We may be starting at the return type of a block.
456  if (state.isProcessingDeclSpec() &&
457  attr.getKind() == ParsedAttr::AT_ObjCOwnership) {
459  declarator, i,
460  /*onlyBlockPointers=*/true)) {
461  moveAttrFromListToList(attr, state.getCurrentAttributes(),
462  dest->getAttrs());
463  return;
464  }
465  }
466  goto error;
467 
468  // Don't walk through these.
472  goto error;
473  }
474  }
475  error:
476 
477  diagnoseBadTypeAttribute(state.getSema(), attr, type);
478 }
479 
480 /// Distribute an objc_gc type attribute that was written on the
481 /// declarator.
483  TypeProcessingState &state, ParsedAttr &attr, QualType &declSpecType) {
484  Declarator &declarator = state.getDeclarator();
485 
486  // objc_gc goes on the innermost pointer to something that's not a
487  // pointer.
488  unsigned innermost = -1U;
489  bool considerDeclSpec = true;
490  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
491  DeclaratorChunk &chunk = declarator.getTypeObject(i);
492  switch (chunk.Kind) {
495  innermost = i;
496  continue;
497 
503  continue;
504 
506  considerDeclSpec = false;
507  goto done;
508  }
509  }
510  done:
511 
512  // That might actually be the decl spec if we weren't blocked by
513  // anything in the declarator.
514  if (considerDeclSpec) {
515  if (handleObjCPointerTypeAttr(state, attr, declSpecType)) {
516  // Splice the attribute into the decl spec. Prevents the
517  // attribute from being applied multiple times and gives
518  // the source-location-filler something to work with.
519  state.saveDeclSpecAttrs();
520  moveAttrFromListToList(attr, declarator.getAttributes(),
521  declarator.getMutableDeclSpec().getAttributes());
522  return;
523  }
524  }
525 
526  // Otherwise, if we found an appropriate chunk, splice the attribute
527  // into it.
528  if (innermost != -1U) {
529  moveAttrFromListToList(attr, declarator.getAttributes(),
530  declarator.getTypeObject(innermost).getAttrs());
531  return;
532  }
533 
534  // Otherwise, diagnose when we're done building the type.
535  declarator.getAttributes().remove(&attr);
536  state.addIgnoredTypeAttr(attr);
537 }
538 
539 /// A function type attribute was written somewhere in a declaration
540 /// *other* than on the declarator itself or in the decl spec. Given
541 /// that it didn't apply in whatever position it was written in, try
542 /// to move it to a more appropriate position.
543 static void distributeFunctionTypeAttr(TypeProcessingState &state,
544  ParsedAttr &attr, QualType type) {
545  Declarator &declarator = state.getDeclarator();
546 
547  // Try to push the attribute from the return type of a function to
548  // the function itself.
549  for (unsigned i = state.getCurrentChunkIndex(); i != 0; --i) {
550  DeclaratorChunk &chunk = declarator.getTypeObject(i-1);
551  switch (chunk.Kind) {
553  moveAttrFromListToList(attr, state.getCurrentAttributes(),
554  chunk.getAttrs());
555  return;
556 
564  continue;
565  }
566  }
567 
568  diagnoseBadTypeAttribute(state.getSema(), attr, type);
569 }
570 
571 /// Try to distribute a function type attribute to the innermost
572 /// function chunk or type. Returns true if the attribute was
573 /// distributed, false if no location was found.
575  TypeProcessingState &state, ParsedAttr &attr,
576  ParsedAttributesView &attrList, QualType &declSpecType) {
577  Declarator &declarator = state.getDeclarator();
578 
579  // Put it on the innermost function chunk, if there is one.
580  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
581  DeclaratorChunk &chunk = declarator.getTypeObject(i);
582  if (chunk.Kind != DeclaratorChunk::Function) continue;
583 
584  moveAttrFromListToList(attr, attrList, chunk.getAttrs());
585  return true;
586  }
587 
588  return handleFunctionTypeAttr(state, attr, declSpecType);
589 }
590 
591 /// A function type attribute was written in the decl spec. Try to
592 /// apply it somewhere.
593 static void distributeFunctionTypeAttrFromDeclSpec(TypeProcessingState &state,
594  ParsedAttr &attr,
595  QualType &declSpecType) {
596  state.saveDeclSpecAttrs();
597 
598  // C++11 attributes before the decl specifiers actually appertain to
599  // the declarators. Move them straight there. We don't support the
600  // 'put them wherever you like' semantics we allow for GNU attributes.
601  if (attr.isCXX11Attribute()) {
602  moveAttrFromListToList(attr, state.getCurrentAttributes(),
603  state.getDeclarator().getAttributes());
604  return;
605  }
606 
607  // Try to distribute to the innermost.
609  state, attr, state.getCurrentAttributes(), declSpecType))
610  return;
611 
612  // If that failed, diagnose the bad attribute when the declarator is
613  // fully built.
614  state.addIgnoredTypeAttr(attr);
615 }
616 
617 /// A function type attribute was written on the declarator. Try to
618 /// apply it somewhere.
619 static void distributeFunctionTypeAttrFromDeclarator(TypeProcessingState &state,
620  ParsedAttr &attr,
621  QualType &declSpecType) {
622  Declarator &declarator = state.getDeclarator();
623 
624  // Try to distribute to the innermost.
626  state, attr, declarator.getAttributes(), declSpecType))
627  return;
628 
629  // If that failed, diagnose the bad attribute when the declarator is
630  // fully built.
631  declarator.getAttributes().remove(&attr);
632  state.addIgnoredTypeAttr(attr);
633 }
634 
635 /// Given that there are attributes written on the declarator
636 /// itself, try to distribute any type attributes to the appropriate
637 /// declarator chunk.
638 ///
639 /// These are attributes like the following:
640 /// int f ATTR;
641 /// int (f ATTR)();
642 /// but not necessarily this:
643 /// int f() ATTR;
644 static void distributeTypeAttrsFromDeclarator(TypeProcessingState &state,
645  QualType &declSpecType) {
646  // Collect all the type attributes from the declarator itself.
647  assert(!state.getDeclarator().getAttributes().empty() &&
648  "declarator has no attrs!");
649  // The called functions in this loop actually remove things from the current
650  // list, so iterating over the existing list isn't possible. Instead, make a
651  // non-owning copy and iterate over that.
652  ParsedAttributesView AttrsCopy{state.getDeclarator().getAttributes()};
653  for (ParsedAttr &attr : AttrsCopy) {
654  // Do not distribute C++11 attributes. They have strict rules for what
655  // they appertain to.
656  if (attr.isCXX11Attribute())
657  continue;
658 
659  switch (attr.getKind()) {
661  distributeObjCPointerTypeAttrFromDeclarator(state, attr, declSpecType);
662  break;
663 
665  distributeFunctionTypeAttrFromDeclarator(state, attr, declSpecType);
666  break;
667 
669  // Microsoft type attributes cannot go after the declarator-id.
670  continue;
671 
673  // Nullability specifiers cannot go after the declarator-id.
674 
675  // Objective-C __kindof does not get distributed.
676  case ParsedAttr::AT_ObjCKindOf:
677  continue;
678 
679  default:
680  break;
681  }
682  }
683 }
684 
685 /// Add a synthetic '()' to a block-literal declarator if it is
686 /// required, given the return type.
687 static void maybeSynthesizeBlockSignature(TypeProcessingState &state,
688  QualType declSpecType) {
689  Declarator &declarator = state.getDeclarator();
690 
691  // First, check whether the declarator would produce a function,
692  // i.e. whether the innermost semantic chunk is a function.
693  if (declarator.isFunctionDeclarator()) {
694  // If so, make that declarator a prototyped declarator.
695  declarator.getFunctionTypeInfo().hasPrototype = true;
696  return;
697  }
698 
699  // If there are any type objects, the type as written won't name a
700  // function, regardless of the decl spec type. This is because a
701  // block signature declarator is always an abstract-declarator, and
702  // abstract-declarators can't just be parentheses chunks. Therefore
703  // we need to build a function chunk unless there are no type
704  // objects and the decl spec type is a function.
705  if (!declarator.getNumTypeObjects() && declSpecType->isFunctionType())
706  return;
707 
708  // Note that there *are* cases with invalid declarators where
709  // declarators consist solely of parentheses. In general, these
710  // occur only in failed efforts to make function declarators, so
711  // faking up the function chunk is still the right thing to do.
712 
713  // Otherwise, we need to fake up a function declarator.
714  SourceLocation loc = declarator.getBeginLoc();
715 
716  // ...and *prepend* it to the declarator.
717  SourceLocation NoLoc;
719  /*HasProto=*/true,
720  /*IsAmbiguous=*/false,
721  /*LParenLoc=*/NoLoc,
722  /*ArgInfo=*/nullptr,
723  /*NumArgs=*/0,
724  /*EllipsisLoc=*/NoLoc,
725  /*RParenLoc=*/NoLoc,
726  /*RefQualifierIsLvalueRef=*/true,
727  /*RefQualifierLoc=*/NoLoc,
728  /*MutableLoc=*/NoLoc, EST_None,
729  /*ESpecRange=*/SourceRange(),
730  /*Exceptions=*/nullptr,
731  /*ExceptionRanges=*/nullptr,
732  /*NumExceptions=*/0,
733  /*NoexceptExpr=*/nullptr,
734  /*ExceptionSpecTokens=*/nullptr,
735  /*DeclsInPrototype=*/None, loc, loc, declarator));
736 
737  // For consistency, make sure the state still has us as processing
738  // the decl spec.
739  assert(state.getCurrentChunkIndex() == declarator.getNumTypeObjects() - 1);
740  state.setCurrentChunkIndex(declarator.getNumTypeObjects());
741 }
742 
744  unsigned &TypeQuals,
745  QualType TypeSoFar,
746  unsigned RemoveTQs,
747  unsigned DiagID) {
748  // If this occurs outside a template instantiation, warn the user about
749  // it; they probably didn't mean to specify a redundant qualifier.
750  typedef std::pair<DeclSpec::TQ, SourceLocation> QualLoc;
751  for (QualLoc Qual : {QualLoc(DeclSpec::TQ_const, DS.getConstSpecLoc()),
754  QualLoc(DeclSpec::TQ_atomic, DS.getAtomicSpecLoc())}) {
755  if (!(RemoveTQs & Qual.first))
756  continue;
757 
758  if (!S.inTemplateInstantiation()) {
759  if (TypeQuals & Qual.first)
760  S.Diag(Qual.second, DiagID)
761  << DeclSpec::getSpecifierName(Qual.first) << TypeSoFar
762  << FixItHint::CreateRemoval(Qual.second);
763  }
764 
765  TypeQuals &= ~Qual.first;
766  }
767 }
768 
769 /// Return true if this is omitted block return type. Also check type
770 /// attributes and type qualifiers when returning true.
771 static bool checkOmittedBlockReturnType(Sema &S, Declarator &declarator,
772  QualType Result) {
773  if (!isOmittedBlockReturnType(declarator))
774  return false;
775 
776  // Warn if we see type attributes for omitted return type on a block literal.
777  SmallVector<ParsedAttr *, 2> ToBeRemoved;
778  for (ParsedAttr &AL : declarator.getMutableDeclSpec().getAttributes()) {
779  if (AL.isInvalid() || !AL.isTypeAttr())
780  continue;
781  S.Diag(AL.getLoc(),
782  diag::warn_block_literal_attributes_on_omitted_return_type)
783  << AL.getName();
784  ToBeRemoved.push_back(&AL);
785  }
786  // Remove bad attributes from the list.
787  for (ParsedAttr *AL : ToBeRemoved)
788  declarator.getMutableDeclSpec().getAttributes().remove(AL);
789 
790  // Warn if we see type qualifiers for omitted return type on a block literal.
791  const DeclSpec &DS = declarator.getDeclSpec();
792  unsigned TypeQuals = DS.getTypeQualifiers();
793  diagnoseAndRemoveTypeQualifiers(S, DS, TypeQuals, Result, (unsigned)-1,
794  diag::warn_block_literal_qualifiers_on_omitted_return_type);
796 
797  return true;
798 }
799 
800 /// Apply Objective-C type arguments to the given type.
803  SourceRange typeArgsRange,
804  bool failOnError = false) {
805  // We can only apply type arguments to an Objective-C class type.
806  const auto *objcObjectType = type->getAs<ObjCObjectType>();
807  if (!objcObjectType || !objcObjectType->getInterface()) {
808  S.Diag(loc, diag::err_objc_type_args_non_class)
809  << type
810  << typeArgsRange;
811 
812  if (failOnError)
813  return QualType();
814  return type;
815  }
816 
817  // The class type must be parameterized.
818  ObjCInterfaceDecl *objcClass = objcObjectType->getInterface();
819  ObjCTypeParamList *typeParams = objcClass->getTypeParamList();
820  if (!typeParams) {
821  S.Diag(loc, diag::err_objc_type_args_non_parameterized_class)
822  << objcClass->getDeclName()
823  << FixItHint::CreateRemoval(typeArgsRange);
824 
825  if (failOnError)
826  return QualType();
827 
828  return type;
829  }
830 
831  // The type must not already be specialized.
832  if (objcObjectType->isSpecialized()) {
833  S.Diag(loc, diag::err_objc_type_args_specialized_class)
834  << type
835  << FixItHint::CreateRemoval(typeArgsRange);
836 
837  if (failOnError)
838  return QualType();
839 
840  return type;
841  }
842 
843  // Check the type arguments.
844  SmallVector<QualType, 4> finalTypeArgs;
845  unsigned numTypeParams = typeParams->size();
846  bool anyPackExpansions = false;
847  for (unsigned i = 0, n = typeArgs.size(); i != n; ++i) {
848  TypeSourceInfo *typeArgInfo = typeArgs[i];
849  QualType typeArg = typeArgInfo->getType();
850 
851  // Type arguments cannot have explicit qualifiers or nullability.
852  // We ignore indirect sources of these, e.g. behind typedefs or
853  // template arguments.
854  if (TypeLoc qual = typeArgInfo->getTypeLoc().findExplicitQualifierLoc()) {
855  bool diagnosed = false;
856  SourceRange rangeToRemove;
857  if (auto attr = qual.getAs<AttributedTypeLoc>()) {
858  rangeToRemove = attr.getLocalSourceRange();
859  if (attr.getTypePtr()->getImmediateNullability()) {
860  typeArg = attr.getTypePtr()->getModifiedType();
861  S.Diag(attr.getBeginLoc(),
862  diag::err_objc_type_arg_explicit_nullability)
863  << typeArg << FixItHint::CreateRemoval(rangeToRemove);
864  diagnosed = true;
865  }
866  }
867 
868  if (!diagnosed) {
869  S.Diag(qual.getBeginLoc(), diag::err_objc_type_arg_qualified)
870  << typeArg << typeArg.getQualifiers().getAsString()
871  << FixItHint::CreateRemoval(rangeToRemove);
872  }
873  }
874 
875  // Remove qualifiers even if they're non-local.
876  typeArg = typeArg.getUnqualifiedType();
877 
878  finalTypeArgs.push_back(typeArg);
879 
880  if (typeArg->getAs<PackExpansionType>())
881  anyPackExpansions = true;
882 
883  // Find the corresponding type parameter, if there is one.
884  ObjCTypeParamDecl *typeParam = nullptr;
885  if (!anyPackExpansions) {
886  if (i < numTypeParams) {
887  typeParam = typeParams->begin()[i];
888  } else {
889  // Too many arguments.
890  S.Diag(loc, diag::err_objc_type_args_wrong_arity)
891  << false
892  << objcClass->getDeclName()
893  << (unsigned)typeArgs.size()
894  << numTypeParams;
895  S.Diag(objcClass->getLocation(), diag::note_previous_decl)
896  << objcClass;
897 
898  if (failOnError)
899  return QualType();
900 
901  return type;
902  }
903  }
904 
905  // Objective-C object pointer types must be substitutable for the bounds.
906  if (const auto *typeArgObjC = typeArg->getAs<ObjCObjectPointerType>()) {
907  // If we don't have a type parameter to match against, assume
908  // everything is fine. There was a prior pack expansion that
909  // means we won't be able to match anything.
910  if (!typeParam) {
911  assert(anyPackExpansions && "Too many arguments?");
912  continue;
913  }
914 
915  // Retrieve the bound.
916  QualType bound = typeParam->getUnderlyingType();
917  const auto *boundObjC = bound->getAs<ObjCObjectPointerType>();
918 
919  // Determine whether the type argument is substitutable for the bound.
920  if (typeArgObjC->isObjCIdType()) {
921  // When the type argument is 'id', the only acceptable type
922  // parameter bound is 'id'.
923  if (boundObjC->isObjCIdType())
924  continue;
925  } else if (S.Context.canAssignObjCInterfaces(boundObjC, typeArgObjC)) {
926  // Otherwise, we follow the assignability rules.
927  continue;
928  }
929 
930  // Diagnose the mismatch.
931  S.Diag(typeArgInfo->getTypeLoc().getBeginLoc(),
932  diag::err_objc_type_arg_does_not_match_bound)
933  << typeArg << bound << typeParam->getDeclName();
934  S.Diag(typeParam->getLocation(), diag::note_objc_type_param_here)
935  << typeParam->getDeclName();
936 
937  if (failOnError)
938  return QualType();
939 
940  return type;
941  }
942 
943  // Block pointer types are permitted for unqualified 'id' bounds.
944  if (typeArg->isBlockPointerType()) {
945  // If we don't have a type parameter to match against, assume
946  // everything is fine. There was a prior pack expansion that
947  // means we won't be able to match anything.
948  if (!typeParam) {
949  assert(anyPackExpansions && "Too many arguments?");
950  continue;
951  }
952 
953  // Retrieve the bound.
954  QualType bound = typeParam->getUnderlyingType();
956  continue;
957 
958  // Diagnose the mismatch.
959  S.Diag(typeArgInfo->getTypeLoc().getBeginLoc(),
960  diag::err_objc_type_arg_does_not_match_bound)
961  << typeArg << bound << typeParam->getDeclName();
962  S.Diag(typeParam->getLocation(), diag::note_objc_type_param_here)
963  << typeParam->getDeclName();
964 
965  if (failOnError)
966  return QualType();
967 
968  return type;
969  }
970 
971  // Dependent types will be checked at instantiation time.
972  if (typeArg->isDependentType()) {
973  continue;
974  }
975 
976  // Diagnose non-id-compatible type arguments.
977  S.Diag(typeArgInfo->getTypeLoc().getBeginLoc(),
978  diag::err_objc_type_arg_not_id_compatible)
979  << typeArg << typeArgInfo->getTypeLoc().getSourceRange();
980 
981  if (failOnError)
982  return QualType();
983 
984  return type;
985  }
986 
987  // Make sure we didn't have the wrong number of arguments.
988  if (!anyPackExpansions && finalTypeArgs.size() != numTypeParams) {
989  S.Diag(loc, diag::err_objc_type_args_wrong_arity)
990  << (typeArgs.size() < typeParams->size())
991  << objcClass->getDeclName()
992  << (unsigned)finalTypeArgs.size()
993  << (unsigned)numTypeParams;
994  S.Diag(objcClass->getLocation(), diag::note_previous_decl)
995  << objcClass;
996 
997  if (failOnError)
998  return QualType();
999 
1000  return type;
1001  }
1002 
1003  // Success. Form the specialized type.
1004  return S.Context.getObjCObjectType(type, finalTypeArgs, { }, false);
1005 }
1006 
1008  SourceLocation ProtocolLAngleLoc,
1009  ArrayRef<ObjCProtocolDecl *> Protocols,
1010  ArrayRef<SourceLocation> ProtocolLocs,
1011  SourceLocation ProtocolRAngleLoc,
1012  bool FailOnError) {
1013  QualType Result = QualType(Decl->getTypeForDecl(), 0);
1014  if (!Protocols.empty()) {
1015  bool HasError;
1016  Result = Context.applyObjCProtocolQualifiers(Result, Protocols,
1017  HasError);
1018  if (HasError) {
1019  Diag(SourceLocation(), diag::err_invalid_protocol_qualifiers)
1020  << SourceRange(ProtocolLAngleLoc, ProtocolRAngleLoc);
1021  if (FailOnError) Result = QualType();
1022  }
1023  if (FailOnError && Result.isNull())
1024  return QualType();
1025  }
1026 
1027  return Result;
1028 }
1029 
1031  SourceLocation Loc,
1032  SourceLocation TypeArgsLAngleLoc,
1033  ArrayRef<TypeSourceInfo *> TypeArgs,
1034  SourceLocation TypeArgsRAngleLoc,
1035  SourceLocation ProtocolLAngleLoc,
1036  ArrayRef<ObjCProtocolDecl *> Protocols,
1037  ArrayRef<SourceLocation> ProtocolLocs,
1038  SourceLocation ProtocolRAngleLoc,
1039  bool FailOnError) {
1040  QualType Result = BaseType;
1041  if (!TypeArgs.empty()) {
1042  Result = applyObjCTypeArgs(*this, Loc, Result, TypeArgs,
1043  SourceRange(TypeArgsLAngleLoc,
1044  TypeArgsRAngleLoc),
1045  FailOnError);
1046  if (FailOnError && Result.isNull())
1047  return QualType();
1048  }
1049 
1050  if (!Protocols.empty()) {
1051  bool HasError;
1052  Result = Context.applyObjCProtocolQualifiers(Result, Protocols,
1053  HasError);
1054  if (HasError) {
1055  Diag(Loc, diag::err_invalid_protocol_qualifiers)
1056  << SourceRange(ProtocolLAngleLoc, ProtocolRAngleLoc);
1057  if (FailOnError) Result = QualType();
1058  }
1059  if (FailOnError && Result.isNull())
1060  return QualType();
1061  }
1062 
1063  return Result;
1064 }
1065 
1067  SourceLocation lAngleLoc,
1068  ArrayRef<Decl *> protocols,
1069  ArrayRef<SourceLocation> protocolLocs,
1070  SourceLocation rAngleLoc) {
1071  // Form id<protocol-list>.
1072  QualType Result = Context.getObjCObjectType(
1073  Context.ObjCBuiltinIdTy, { },
1074  llvm::makeArrayRef(
1075  (ObjCProtocolDecl * const *)protocols.data(),
1076  protocols.size()),
1077  false);
1078  Result = Context.getObjCObjectPointerType(Result);
1079 
1080  TypeSourceInfo *ResultTInfo = Context.CreateTypeSourceInfo(Result);
1081  TypeLoc ResultTL = ResultTInfo->getTypeLoc();
1082 
1083  auto ObjCObjectPointerTL = ResultTL.castAs<ObjCObjectPointerTypeLoc>();
1084  ObjCObjectPointerTL.setStarLoc(SourceLocation()); // implicit
1085 
1086  auto ObjCObjectTL = ObjCObjectPointerTL.getPointeeLoc()
1087  .castAs<ObjCObjectTypeLoc>();
1088  ObjCObjectTL.setHasBaseTypeAsWritten(false);
1089  ObjCObjectTL.getBaseLoc().initialize(Context, SourceLocation());
1090 
1091  // No type arguments.
1092  ObjCObjectTL.setTypeArgsLAngleLoc(SourceLocation());
1093  ObjCObjectTL.setTypeArgsRAngleLoc(SourceLocation());
1094 
1095  // Fill in protocol qualifiers.
1096  ObjCObjectTL.setProtocolLAngleLoc(lAngleLoc);
1097  ObjCObjectTL.setProtocolRAngleLoc(rAngleLoc);
1098  for (unsigned i = 0, n = protocols.size(); i != n; ++i)
1099  ObjCObjectTL.setProtocolLoc(i, protocolLocs[i]);
1100 
1101  // We're done. Return the completed type to the parser.
1102  return CreateParsedType(Result, ResultTInfo);
1103 }
1104 
1106  Scope *S,
1107  SourceLocation Loc,
1108  ParsedType BaseType,
1109  SourceLocation TypeArgsLAngleLoc,
1110  ArrayRef<ParsedType> TypeArgs,
1111  SourceLocation TypeArgsRAngleLoc,
1112  SourceLocation ProtocolLAngleLoc,
1113  ArrayRef<Decl *> Protocols,
1114  ArrayRef<SourceLocation> ProtocolLocs,
1115  SourceLocation ProtocolRAngleLoc) {
1116  TypeSourceInfo *BaseTypeInfo = nullptr;
1117  QualType T = GetTypeFromParser(BaseType, &BaseTypeInfo);
1118  if (T.isNull())
1119  return true;
1120 
1121  // Handle missing type-source info.
1122  if (!BaseTypeInfo)
1123  BaseTypeInfo = Context.getTrivialTypeSourceInfo(T, Loc);
1124 
1125  // Extract type arguments.
1126  SmallVector<TypeSourceInfo *, 4> ActualTypeArgInfos;
1127  for (unsigned i = 0, n = TypeArgs.size(); i != n; ++i) {
1128  TypeSourceInfo *TypeArgInfo = nullptr;
1129  QualType TypeArg = GetTypeFromParser(TypeArgs[i], &TypeArgInfo);
1130  if (TypeArg.isNull()) {
1131  ActualTypeArgInfos.clear();
1132  break;
1133  }
1134 
1135  assert(TypeArgInfo && "No type source info?");
1136  ActualTypeArgInfos.push_back(TypeArgInfo);
1137  }
1138 
1139  // Build the object type.
1140  QualType Result = BuildObjCObjectType(
1141  T, BaseTypeInfo->getTypeLoc().getSourceRange().getBegin(),
1142  TypeArgsLAngleLoc, ActualTypeArgInfos, TypeArgsRAngleLoc,
1143  ProtocolLAngleLoc,
1144  llvm::makeArrayRef((ObjCProtocolDecl * const *)Protocols.data(),
1145  Protocols.size()),
1146  ProtocolLocs, ProtocolRAngleLoc,
1147  /*FailOnError=*/false);
1148 
1149  if (Result == T)
1150  return BaseType;
1151 
1152  // Create source information for this type.
1153  TypeSourceInfo *ResultTInfo = Context.CreateTypeSourceInfo(Result);
1154  TypeLoc ResultTL = ResultTInfo->getTypeLoc();
1155 
1156  // For id<Proto1, Proto2> or Class<Proto1, Proto2>, we'll have an
1157  // object pointer type. Fill in source information for it.
1158  if (auto ObjCObjectPointerTL = ResultTL.getAs<ObjCObjectPointerTypeLoc>()) {
1159  // The '*' is implicit.
1160  ObjCObjectPointerTL.setStarLoc(SourceLocation());
1161  ResultTL = ObjCObjectPointerTL.getPointeeLoc();
1162  }
1163 
1164  if (auto OTPTL = ResultTL.getAs<ObjCTypeParamTypeLoc>()) {
1165  // Protocol qualifier information.
1166  if (OTPTL.getNumProtocols() > 0) {
1167  assert(OTPTL.getNumProtocols() == Protocols.size());
1168  OTPTL.setProtocolLAngleLoc(ProtocolLAngleLoc);
1169  OTPTL.setProtocolRAngleLoc(ProtocolRAngleLoc);
1170  for (unsigned i = 0, n = Protocols.size(); i != n; ++i)
1171  OTPTL.setProtocolLoc(i, ProtocolLocs[i]);
1172  }
1173 
1174  // We're done. Return the completed type to the parser.
1175  return CreateParsedType(Result, ResultTInfo);
1176  }
1177 
1178  auto ObjCObjectTL = ResultTL.castAs<ObjCObjectTypeLoc>();
1179 
1180  // Type argument information.
1181  if (ObjCObjectTL.getNumTypeArgs() > 0) {
1182  assert(ObjCObjectTL.getNumTypeArgs() == ActualTypeArgInfos.size());
1183  ObjCObjectTL.setTypeArgsLAngleLoc(TypeArgsLAngleLoc);
1184  ObjCObjectTL.setTypeArgsRAngleLoc(TypeArgsRAngleLoc);
1185  for (unsigned i = 0, n = ActualTypeArgInfos.size(); i != n; ++i)
1186  ObjCObjectTL.setTypeArgTInfo(i, ActualTypeArgInfos[i]);
1187  } else {
1188  ObjCObjectTL.setTypeArgsLAngleLoc(SourceLocation());
1189  ObjCObjectTL.setTypeArgsRAngleLoc(SourceLocation());
1190  }
1191 
1192  // Protocol qualifier information.
1193  if (ObjCObjectTL.getNumProtocols() > 0) {
1194  assert(ObjCObjectTL.getNumProtocols() == Protocols.size());
1195  ObjCObjectTL.setProtocolLAngleLoc(ProtocolLAngleLoc);
1196  ObjCObjectTL.setProtocolRAngleLoc(ProtocolRAngleLoc);
1197  for (unsigned i = 0, n = Protocols.size(); i != n; ++i)
1198  ObjCObjectTL.setProtocolLoc(i, ProtocolLocs[i]);
1199  } else {
1200  ObjCObjectTL.setProtocolLAngleLoc(SourceLocation());
1201  ObjCObjectTL.setProtocolRAngleLoc(SourceLocation());
1202  }
1203 
1204  // Base type.
1205  ObjCObjectTL.setHasBaseTypeAsWritten(true);
1206  if (ObjCObjectTL.getType() == T)
1207  ObjCObjectTL.getBaseLoc().initializeFullCopy(BaseTypeInfo->getTypeLoc());
1208  else
1209  ObjCObjectTL.getBaseLoc().initialize(Context, Loc);
1210 
1211  // We're done. Return the completed type to the parser.
1212  return CreateParsedType(Result, ResultTInfo);
1213 }
1214 
1215 static OpenCLAccessAttr::Spelling
1217  for (const ParsedAttr &AL : Attrs)
1218  if (AL.getKind() == ParsedAttr::AT_OpenCLAccess)
1219  return static_cast<OpenCLAccessAttr::Spelling>(AL.getSemanticSpelling());
1220  return OpenCLAccessAttr::Keyword_read_only;
1221 }
1222 
1223 /// Convert the specified declspec to the appropriate type
1224 /// object.
1225 /// \param state Specifies the declarator containing the declaration specifier
1226 /// to be converted, along with other associated processing state.
1227 /// \returns The type described by the declaration specifiers. This function
1228 /// never returns null.
1229 static QualType ConvertDeclSpecToType(TypeProcessingState &state) {
1230  // FIXME: Should move the logic from DeclSpec::Finish to here for validity
1231  // checking.
1232 
1233  Sema &S = state.getSema();
1234  Declarator &declarator = state.getDeclarator();
1235  DeclSpec &DS = declarator.getMutableDeclSpec();
1236  SourceLocation DeclLoc = declarator.getIdentifierLoc();
1237  if (DeclLoc.isInvalid())
1238  DeclLoc = DS.getBeginLoc();
1239 
1240  ASTContext &Context = S.Context;
1241 
1242  QualType Result;
1243  switch (DS.getTypeSpecType()) {
1244  case DeclSpec::TST_void:
1245  Result = Context.VoidTy;
1246  break;
1247  case DeclSpec::TST_char:
1249  Result = Context.CharTy;
1250  else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed)
1251  Result = Context.SignedCharTy;
1252  else {
1253  assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned &&
1254  "Unknown TSS value");
1255  Result = Context.UnsignedCharTy;
1256  }
1257  break;
1258  case DeclSpec::TST_wchar:
1260  Result = Context.WCharTy;
1261  else if (DS.getTypeSpecSign() == DeclSpec::TSS_signed) {
1262  S.Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec)
1263  << DS.getSpecifierName(DS.getTypeSpecType(),
1264  Context.getPrintingPolicy());
1265  Result = Context.getSignedWCharType();
1266  } else {
1267  assert(DS.getTypeSpecSign() == DeclSpec::TSS_unsigned &&
1268  "Unknown TSS value");
1269  S.Diag(DS.getTypeSpecSignLoc(), diag::ext_invalid_sign_spec)
1270  << DS.getSpecifierName(DS.getTypeSpecType(),
1271  Context.getPrintingPolicy());
1272  Result = Context.getUnsignedWCharType();
1273  }
1274  break;
1275  case DeclSpec::TST_char8:
1276  assert(DS.getTypeSpecSign() == DeclSpec::TSS_unspecified &&
1277  "Unknown TSS value");
1278  Result = Context.Char8Ty;
1279  break;
1280  case DeclSpec::TST_char16:
1281  assert(DS.getTypeSpecSign() == DeclSpec::TSS_unspecified &&
1282  "Unknown TSS value");
1283  Result = Context.Char16Ty;
1284  break;
1285  case DeclSpec::TST_char32:
1286  assert(DS.getTypeSpecSign() == DeclSpec::TSS_unspecified &&
1287  "Unknown TSS value");
1288  Result = Context.Char32Ty;
1289  break;
1291  // If this is a missing declspec in a block literal return context, then it
1292  // is inferred from the return statements inside the block.
1293  // The declspec is always missing in a lambda expr context; it is either
1294  // specified with a trailing return type or inferred.
1295  if (S.getLangOpts().CPlusPlus14 &&
1297  // In C++1y, a lambda's implicit return type is 'auto'.
1298  Result = Context.getAutoDeductType();
1299  break;
1300  } else if (declarator.getContext() ==
1302  checkOmittedBlockReturnType(S, declarator,
1303  Context.DependentTy)) {
1304  Result = Context.DependentTy;
1305  break;
1306  }
1307 
1308  // Unspecified typespec defaults to int in C90. However, the C90 grammar
1309  // [C90 6.5] only allows a decl-spec if there was *some* type-specifier,
1310  // type-qualifier, or storage-class-specifier. If not, emit an extwarn.
1311  // Note that the one exception to this is function definitions, which are
1312  // allowed to be completely missing a declspec. This is handled in the
1313  // parser already though by it pretending to have seen an 'int' in this
1314  // case.
1315  if (S.getLangOpts().ImplicitInt) {
1316  // In C89 mode, we only warn if there is a completely missing declspec
1317  // when one is not allowed.
1318  if (DS.isEmpty()) {
1319  S.Diag(DeclLoc, diag::ext_missing_declspec)
1320  << DS.getSourceRange()
1321  << FixItHint::CreateInsertion(DS.getBeginLoc(), "int");
1322  }
1323  } else if (!DS.hasTypeSpecifier()) {
1324  // C99 and C++ require a type specifier. For example, C99 6.7.2p2 says:
1325  // "At least one type specifier shall be given in the declaration
1326  // specifiers in each declaration, and in the specifier-qualifier list in
1327  // each struct declaration and type name."
1328  if (S.getLangOpts().CPlusPlus) {
1329  S.Diag(DeclLoc, diag::err_missing_type_specifier)
1330  << DS.getSourceRange();
1331 
1332  // When this occurs in C++ code, often something is very broken with the
1333  // value being declared, poison it as invalid so we don't get chains of
1334  // errors.
1335  declarator.setInvalidType(true);
1336  } else if (S.getLangOpts().OpenCLVersion >= 200 && DS.isTypeSpecPipe()){
1337  S.Diag(DeclLoc, diag::err_missing_actual_pipe_type)
1338  << DS.getSourceRange();
1339  declarator.setInvalidType(true);
1340  } else {
1341  S.Diag(DeclLoc, diag::ext_missing_type_specifier)
1342  << DS.getSourceRange();
1343  }
1344  }
1345 
1346  LLVM_FALLTHROUGH;
1347  case DeclSpec::TST_int: {
1349  switch (DS.getTypeSpecWidth()) {
1350  case DeclSpec::TSW_unspecified: Result = Context.IntTy; break;
1351  case DeclSpec::TSW_short: Result = Context.ShortTy; break;
1352  case DeclSpec::TSW_long: Result = Context.LongTy; break;
1354  Result = Context.LongLongTy;
1355 
1356  // 'long long' is a C99 or C++11 feature.
1357  if (!S.getLangOpts().C99) {
1358  if (S.getLangOpts().CPlusPlus)
1359  S.Diag(DS.getTypeSpecWidthLoc(),
1360  S.getLangOpts().CPlusPlus11 ?
1361  diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
1362  else
1363  S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
1364  }
1365  break;
1366  }
1367  } else {
1368  switch (DS.getTypeSpecWidth()) {
1369  case DeclSpec::TSW_unspecified: Result = Context.UnsignedIntTy; break;
1370  case DeclSpec::TSW_short: Result = Context.UnsignedShortTy; break;
1371  case DeclSpec::TSW_long: Result = Context.UnsignedLongTy; break;
1373  Result = Context.UnsignedLongLongTy;
1374 
1375  // 'long long' is a C99 or C++11 feature.
1376  if (!S.getLangOpts().C99) {
1377  if (S.getLangOpts().CPlusPlus)
1378  S.Diag(DS.getTypeSpecWidthLoc(),
1379  S.getLangOpts().CPlusPlus11 ?
1380  diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
1381  else
1382  S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
1383  }
1384  break;
1385  }
1386  }
1387  break;
1388  }
1389  case DeclSpec::TST_accum: {
1390  switch (DS.getTypeSpecWidth()) {
1391  case DeclSpec::TSW_short:
1392  Result = Context.ShortAccumTy;
1393  break;
1395  Result = Context.AccumTy;
1396  break;
1397  case DeclSpec::TSW_long:
1398  Result = Context.LongAccumTy;
1399  break;
1401  llvm_unreachable("Unable to specify long long as _Accum width");
1402  }
1403 
1405  Result = Context.getCorrespondingUnsignedType(Result);
1406 
1407  if (DS.isTypeSpecSat())
1408  Result = Context.getCorrespondingSaturatedType(Result);
1409 
1410  break;
1411  }
1412  case DeclSpec::TST_fract: {
1413  switch (DS.getTypeSpecWidth()) {
1414  case DeclSpec::TSW_short:
1415  Result = Context.ShortFractTy;
1416  break;
1418  Result = Context.FractTy;
1419  break;
1420  case DeclSpec::TSW_long:
1421  Result = Context.LongFractTy;
1422  break;
1424  llvm_unreachable("Unable to specify long long as _Fract width");
1425  }
1426 
1428  Result = Context.getCorrespondingUnsignedType(Result);
1429 
1430  if (DS.isTypeSpecSat())
1431  Result = Context.getCorrespondingSaturatedType(Result);
1432 
1433  break;
1434  }
1435  case DeclSpec::TST_int128:
1436  if (!S.Context.getTargetInfo().hasInt128Type())
1437  S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_unsupported)
1438  << "__int128";
1440  Result = Context.UnsignedInt128Ty;
1441  else
1442  Result = Context.Int128Ty;
1443  break;
1444  case DeclSpec::TST_float16:
1445  // CUDA host and device may have different _Float16 support, therefore
1446  // do not diagnose _Float16 usage to avoid false alarm.
1447  // ToDo: more precise diagnostics for CUDA.
1448  if (!S.Context.getTargetInfo().hasFloat16Type() && !S.getLangOpts().CUDA)
1449  S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_unsupported)
1450  << "_Float16";
1451  Result = Context.Float16Ty;
1452  break;
1453  case DeclSpec::TST_half: Result = Context.HalfTy; break;
1454  case DeclSpec::TST_float: Result = Context.FloatTy; break;
1455  case DeclSpec::TST_double:
1457  Result = Context.LongDoubleTy;
1458  else
1459  Result = Context.DoubleTy;
1460  break;
1463  S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_unsupported)
1464  << "__float128";
1465  Result = Context.Float128Ty;
1466  break;
1467  case DeclSpec::TST_bool: Result = Context.BoolTy; break; // _Bool or bool
1468  break;
1469  case DeclSpec::TST_decimal32: // _Decimal32
1470  case DeclSpec::TST_decimal64: // _Decimal64
1471  case DeclSpec::TST_decimal128: // _Decimal128
1472  S.Diag(DS.getTypeSpecTypeLoc(), diag::err_decimal_unsupported);
1473  Result = Context.IntTy;
1474  declarator.setInvalidType(true);
1475  break;
1476  case DeclSpec::TST_class:
1477  case DeclSpec::TST_enum:
1478  case DeclSpec::TST_union:
1479  case DeclSpec::TST_struct:
1480  case DeclSpec::TST_interface: {
1481  TagDecl *D = dyn_cast_or_null<TagDecl>(DS.getRepAsDecl());
1482  if (!D) {
1483  // This can happen in C++ with ambiguous lookups.
1484  Result = Context.IntTy;
1485  declarator.setInvalidType(true);
1486  break;
1487  }
1488 
1489  // If the type is deprecated or unavailable, diagnose it.
1491 
1492  assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 &&
1493  DS.getTypeSpecSign() == 0 && "No qualifiers on tag names!");
1494 
1495  // TypeQuals handled by caller.
1496  Result = Context.getTypeDeclType(D);
1497 
1498  // In both C and C++, make an ElaboratedType.
1499  ElaboratedTypeKeyword Keyword
1501  Result = S.getElaboratedType(Keyword, DS.getTypeSpecScope(), Result,
1502  DS.isTypeSpecOwned() ? D : nullptr);
1503  break;
1504  }
1505  case DeclSpec::TST_typename: {
1506  assert(DS.getTypeSpecWidth() == 0 && DS.getTypeSpecComplex() == 0 &&
1507  DS.getTypeSpecSign() == 0 &&
1508  "Can't handle qualifiers on typedef names yet!");
1509  Result = S.GetTypeFromParser(DS.getRepAsType());
1510  if (Result.isNull()) {
1511  declarator.setInvalidType(true);
1512  }
1513 
1514  // TypeQuals handled by caller.
1515  break;
1516  }
1518  // FIXME: Preserve type source info.
1519  Result = S.GetTypeFromParser(DS.getRepAsType());
1520  assert(!Result.isNull() && "Didn't get a type for typeof?");
1521  if (!Result->isDependentType())
1522  if (const TagType *TT = Result->getAs<TagType>())
1523  S.DiagnoseUseOfDecl(TT->getDecl(), DS.getTypeSpecTypeLoc());
1524  // TypeQuals handled by caller.
1525  Result = Context.getTypeOfType(Result);
1526  break;
1527  case DeclSpec::TST_typeofExpr: {
1528  Expr *E = DS.getRepAsExpr();
1529  assert(E && "Didn't get an expression for typeof?");
1530  // TypeQuals handled by caller.
1531  Result = S.BuildTypeofExprType(E, DS.getTypeSpecTypeLoc());
1532  if (Result.isNull()) {
1533  Result = Context.IntTy;
1534  declarator.setInvalidType(true);
1535  }
1536  break;
1537  }
1538  case DeclSpec::TST_decltype: {
1539  Expr *E = DS.getRepAsExpr();
1540  assert(E && "Didn't get an expression for decltype?");
1541  // TypeQuals handled by caller.
1542  Result = S.BuildDecltypeType(E, DS.getTypeSpecTypeLoc());
1543  if (Result.isNull()) {
1544  Result = Context.IntTy;
1545  declarator.setInvalidType(true);
1546  }
1547  break;
1548  }
1550  Result = S.GetTypeFromParser(DS.getRepAsType());
1551  assert(!Result.isNull() && "Didn't get a type for __underlying_type?");
1552  Result = S.BuildUnaryTransformType(Result,
1554  DS.getTypeSpecTypeLoc());
1555  if (Result.isNull()) {
1556  Result = Context.IntTy;
1557  declarator.setInvalidType(true);
1558  }
1559  break;
1560 
1561  case DeclSpec::TST_auto:
1562  Result = Context.getAutoType(QualType(), AutoTypeKeyword::Auto, false);
1563  break;
1564 
1566  Result = Context.getAutoType(QualType(), AutoTypeKeyword::GNUAutoType, false);
1567  break;
1568 
1571  /*IsDependent*/ false);
1572  break;
1573 
1575  Result = Context.UnknownAnyTy;
1576  break;
1577 
1578  case DeclSpec::TST_atomic:
1579  Result = S.GetTypeFromParser(DS.getRepAsType());
1580  assert(!Result.isNull() && "Didn't get a type for _Atomic?");
1581  Result = S.BuildAtomicType(Result, DS.getTypeSpecTypeLoc());
1582  if (Result.isNull()) {
1583  Result = Context.IntTy;
1584  declarator.setInvalidType(true);
1585  }
1586  break;
1587 
1588 #define GENERIC_IMAGE_TYPE(ImgType, Id) \
1589  case DeclSpec::TST_##ImgType##_t: \
1590  switch (getImageAccess(DS.getAttributes())) { \
1591  case OpenCLAccessAttr::Keyword_write_only: \
1592  Result = Context.Id##WOTy; \
1593  break; \
1594  case OpenCLAccessAttr::Keyword_read_write: \
1595  Result = Context.Id##RWTy; \
1596  break; \
1597  case OpenCLAccessAttr::Keyword_read_only: \
1598  Result = Context.Id##ROTy; \
1599  break; \
1600  } \
1601  break;
1602 #include "clang/Basic/OpenCLImageTypes.def"
1603 
1604  case DeclSpec::TST_error:
1605  Result = Context.IntTy;
1606  declarator.setInvalidType(true);
1607  break;
1608  }
1609 
1610  if (S.getLangOpts().OpenCL &&
1612  declarator.setInvalidType(true);
1613 
1614  bool IsFixedPointType = DS.getTypeSpecType() == DeclSpec::TST_accum ||
1615  DS.getTypeSpecType() == DeclSpec::TST_fract;
1616 
1617  // Only fixed point types can be saturated
1618  if (DS.isTypeSpecSat() && !IsFixedPointType)
1619  S.Diag(DS.getTypeSpecSatLoc(), diag::err_invalid_saturation_spec)
1620  << DS.getSpecifierName(DS.getTypeSpecType(),
1621  Context.getPrintingPolicy());
1622 
1623  // Handle complex types.
1624  if (DS.getTypeSpecComplex() == DeclSpec::TSC_complex) {
1625  if (S.getLangOpts().Freestanding)
1626  S.Diag(DS.getTypeSpecComplexLoc(), diag::ext_freestanding_complex);
1627  Result = Context.getComplexType(Result);
1628  } else if (DS.isTypeAltiVecVector()) {
1629  unsigned typeSize = static_cast<unsigned>(Context.getTypeSize(Result));
1630  assert(typeSize > 0 && "type size for vector must be greater than 0 bits");
1632  if (DS.isTypeAltiVecPixel())
1633  VecKind = VectorType::AltiVecPixel;
1634  else if (DS.isTypeAltiVecBool())
1635  VecKind = VectorType::AltiVecBool;
1636  Result = Context.getVectorType(Result, 128/typeSize, VecKind);
1637  }
1638 
1639  // FIXME: Imaginary.
1640  if (DS.getTypeSpecComplex() == DeclSpec::TSC_imaginary)
1641  S.Diag(DS.getTypeSpecComplexLoc(), diag::err_imaginary_not_supported);
1642 
1643  // Before we process any type attributes, synthesize a block literal
1644  // function declarator if necessary.
1645  if (declarator.getContext() == DeclaratorContext::BlockLiteralContext)
1647 
1648  // Apply any type attributes from the decl spec. This may cause the
1649  // list of type attributes to be temporarily saved while the type
1650  // attributes are pushed around.
1651  // pipe attributes will be handled later ( at GetFullTypeForDeclarator )
1652  if (!DS.isTypeSpecPipe())
1653  processTypeAttrs(state, Result, TAL_DeclSpec, DS.getAttributes());
1654 
1655  // Apply const/volatile/restrict qualifiers to T.
1656  if (unsigned TypeQuals = DS.getTypeQualifiers()) {
1657  // Warn about CV qualifiers on function types.
1658  // C99 6.7.3p8:
1659  // If the specification of a function type includes any type qualifiers,
1660  // the behavior is undefined.
1661  // C++11 [dcl.fct]p7:
1662  // The effect of a cv-qualifier-seq in a function declarator is not the
1663  // same as adding cv-qualification on top of the function type. In the
1664  // latter case, the cv-qualifiers are ignored.
1665  if (TypeQuals && Result->isFunctionType()) {
1667  S, DS, TypeQuals, Result, DeclSpec::TQ_const | DeclSpec::TQ_volatile,
1668  S.getLangOpts().CPlusPlus
1669  ? diag::warn_typecheck_function_qualifiers_ignored
1670  : diag::warn_typecheck_function_qualifiers_unspecified);
1671  // No diagnostic for 'restrict' or '_Atomic' applied to a
1672  // function type; we'll diagnose those later, in BuildQualifiedType.
1673  }
1674 
1675  // C++11 [dcl.ref]p1:
1676  // Cv-qualified references are ill-formed except when the
1677  // cv-qualifiers are introduced through the use of a typedef-name
1678  // or decltype-specifier, in which case the cv-qualifiers are ignored.
1679  //
1680  // There don't appear to be any other contexts in which a cv-qualified
1681  // reference type could be formed, so the 'ill-formed' clause here appears
1682  // to never happen.
1683  if (TypeQuals && Result->isReferenceType()) {
1685  S, DS, TypeQuals, Result,
1687  diag::warn_typecheck_reference_qualifiers);
1688  }
1689 
1690  // C90 6.5.3 constraints: "The same type qualifier shall not appear more
1691  // than once in the same specifier-list or qualifier-list, either directly
1692  // or via one or more typedefs."
1693  if (!S.getLangOpts().C99 && !S.getLangOpts().CPlusPlus
1694  && TypeQuals & Result.getCVRQualifiers()) {
1695  if (TypeQuals & DeclSpec::TQ_const && Result.isConstQualified()) {
1696  S.Diag(DS.getConstSpecLoc(), diag::ext_duplicate_declspec)
1697  << "const";
1698  }
1699 
1700  if (TypeQuals & DeclSpec::TQ_volatile && Result.isVolatileQualified()) {
1701  S.Diag(DS.getVolatileSpecLoc(), diag::ext_duplicate_declspec)
1702  << "volatile";
1703  }
1704 
1705  // C90 doesn't have restrict nor _Atomic, so it doesn't force us to
1706  // produce a warning in this case.
1707  }
1708 
1709  QualType Qualified = S.BuildQualifiedType(Result, DeclLoc, TypeQuals, &DS);
1710 
1711  // If adding qualifiers fails, just use the unqualified type.
1712  if (Qualified.isNull())
1713  declarator.setInvalidType(true);
1714  else
1715  Result = Qualified;
1716  }
1717 
1718  assert(!Result.isNull() && "This function should not return a null type");
1719  return Result;
1720 }
1721 
1722 static std::string getPrintableNameForEntity(DeclarationName Entity) {
1723  if (Entity)
1724  return Entity.getAsString();
1725 
1726  return "type name";
1727 }
1728 
1730  Qualifiers Qs, const DeclSpec *DS) {
1731  if (T.isNull())
1732  return QualType();
1733 
1734  // Ignore any attempt to form a cv-qualified reference.
1735  if (T->isReferenceType()) {
1736  Qs.removeConst();
1737  Qs.removeVolatile();
1738  }
1739 
1740  // Enforce C99 6.7.3p2: "Types other than pointer types derived from
1741  // object or incomplete types shall not be restrict-qualified."
1742  if (Qs.hasRestrict()) {
1743  unsigned DiagID = 0;
1744  QualType ProblemTy;
1745 
1746  if (T->isAnyPointerType() || T->isReferenceType() ||
1747  T->isMemberPointerType()) {
1748  QualType EltTy;
1749  if (T->isObjCObjectPointerType())
1750  EltTy = T;
1751  else if (const MemberPointerType *PTy = T->getAs<MemberPointerType>())
1752  EltTy = PTy->getPointeeType();
1753  else
1754  EltTy = T->getPointeeType();
1755 
1756  // If we have a pointer or reference, the pointee must have an object
1757  // incomplete type.
1758  if (!EltTy->isIncompleteOrObjectType()) {
1759  DiagID = diag::err_typecheck_invalid_restrict_invalid_pointee;
1760  ProblemTy = EltTy;
1761  }
1762  } else if (!T->isDependentType()) {
1763  DiagID = diag::err_typecheck_invalid_restrict_not_pointer;
1764  ProblemTy = T;
1765  }
1766 
1767  if (DiagID) {
1768  Diag(DS ? DS->getRestrictSpecLoc() : Loc, DiagID) << ProblemTy;
1769  Qs.removeRestrict();
1770  }
1771  }
1772 
1773  return Context.getQualifiedType(T, Qs);
1774 }
1775 
1777  unsigned CVRAU, const DeclSpec *DS) {
1778  if (T.isNull())
1779  return QualType();
1780 
1781  // Ignore any attempt to form a cv-qualified reference.
1782  if (T->isReferenceType())
1783  CVRAU &=
1785 
1786  // Convert from DeclSpec::TQ to Qualifiers::TQ by just dropping TQ_atomic and
1787  // TQ_unaligned;
1788  unsigned CVR = CVRAU & ~(DeclSpec::TQ_atomic | DeclSpec::TQ_unaligned);
1789 
1790  // C11 6.7.3/5:
1791  // If the same qualifier appears more than once in the same
1792  // specifier-qualifier-list, either directly or via one or more typedefs,
1793  // the behavior is the same as if it appeared only once.
1794  //
1795  // It's not specified what happens when the _Atomic qualifier is applied to
1796  // a type specified with the _Atomic specifier, but we assume that this
1797  // should be treated as if the _Atomic qualifier appeared multiple times.
1798  if (CVRAU & DeclSpec::TQ_atomic && !T->isAtomicType()) {
1799  // C11 6.7.3/5:
1800  // If other qualifiers appear along with the _Atomic qualifier in a
1801  // specifier-qualifier-list, the resulting type is the so-qualified
1802  // atomic type.
1803  //
1804  // Don't need to worry about array types here, since _Atomic can't be
1805  // applied to such types.
1807  T = BuildAtomicType(QualType(Split.Ty, 0),
1808  DS ? DS->getAtomicSpecLoc() : Loc);
1809  if (T.isNull())
1810  return T;
1811  Split.Quals.addCVRQualifiers(CVR);
1812  return BuildQualifiedType(T, Loc, Split.Quals);
1813  }
1814 
1817  return BuildQualifiedType(T, Loc, Q, DS);
1818 }
1819 
1820 /// Build a paren type including \p T.
1822  return Context.getParenType(T);
1823 }
1824 
1825 /// Given that we're building a pointer or reference to the given
1827  SourceLocation loc,
1828  bool isReference) {
1829  // Bail out if retention is unrequired or already specified.
1830  if (!type->isObjCLifetimeType() ||
1832  return type;
1833 
1835 
1836  // If the object type is const-qualified, we can safely use
1837  // __unsafe_unretained. This is safe (because there are no read
1838  // barriers), and it'll be safe to coerce anything but __weak* to
1839  // the resulting type.
1840  if (type.isConstQualified()) {
1841  implicitLifetime = Qualifiers::OCL_ExplicitNone;
1842 
1843  // Otherwise, check whether the static type does not require
1844  // retaining. This currently only triggers for Class (possibly
1845  // protocol-qualifed, and arrays thereof).
1846  } else if (type->isObjCARCImplicitlyUnretainedType()) {
1847  implicitLifetime = Qualifiers::OCL_ExplicitNone;
1848 
1849  // If we are in an unevaluated context, like sizeof, skip adding a
1850  // qualification.
1851  } else if (S.isUnevaluatedContext()) {
1852  return type;
1853 
1854  // If that failed, give an error and recover using __strong. __strong
1855  // is the option most likely to prevent spurious second-order diagnostics,
1856  // like when binding a reference to a field.
1857  } else {
1858  // These types can show up in private ivars in system headers, so
1859  // we need this to not be an error in those cases. Instead we
1860  // want to delay.
1864  diag::err_arc_indirect_no_ownership, type, isReference));
1865  } else {
1866  S.Diag(loc, diag::err_arc_indirect_no_ownership) << type << isReference;
1867  }
1868  implicitLifetime = Qualifiers::OCL_Strong;
1869  }
1870  assert(implicitLifetime && "didn't infer any lifetime!");
1871 
1872  Qualifiers qs;
1873  qs.addObjCLifetime(implicitLifetime);
1874  return S.Context.getQualifiedType(type, qs);
1875 }
1876 
1877 static std::string getFunctionQualifiersAsString(const FunctionProtoType *FnTy){
1878  std::string Quals = FnTy->getMethodQuals().getAsString();
1879 
1880  switch (FnTy->getRefQualifier()) {
1881  case RQ_None:
1882  break;
1883 
1884  case RQ_LValue:
1885  if (!Quals.empty())
1886  Quals += ' ';
1887  Quals += '&';
1888  break;
1889 
1890  case RQ_RValue:
1891  if (!Quals.empty())
1892  Quals += ' ';
1893  Quals += "&&";
1894  break;
1895  }
1896 
1897  return Quals;
1898 }
1899 
1900 namespace {
1901 /// Kinds of declarator that cannot contain a qualified function type.
1902 ///
1903 /// C++98 [dcl.fct]p4 / C++11 [dcl.fct]p6:
1904 /// a function type with a cv-qualifier or a ref-qualifier can only appear
1905 /// at the topmost level of a type.
1906 ///
1907 /// Parens and member pointers are permitted. We don't diagnose array and
1908 /// function declarators, because they don't allow function types at all.
1909 ///
1910 /// The values of this enum are used in diagnostics.
1911 enum QualifiedFunctionKind { QFK_BlockPointer, QFK_Pointer, QFK_Reference };
1912 } // end anonymous namespace
1913 
1914 /// Check whether the type T is a qualified function type, and if it is,
1915 /// diagnose that it cannot be contained within the given kind of declarator.
1917  QualifiedFunctionKind QFK) {
1918  // Does T refer to a function type with a cv-qualifier or a ref-qualifier?
1919  const FunctionProtoType *FPT = T->getAs<FunctionProtoType>();
1920  if (!FPT || (FPT->getMethodQuals().empty() && FPT->getRefQualifier() == RQ_None))
1921  return false;
1922 
1923  S.Diag(Loc, diag::err_compound_qualified_function_type)
1924  << QFK << isa<FunctionType>(T.IgnoreParens()) << T
1926  return true;
1927 }
1928 
1929 /// Build a pointer type.
1930 ///
1931 /// \param T The type to which we'll be building a pointer.
1932 ///
1933 /// \param Loc The location of the entity whose type involves this
1934 /// pointer type or, if there is no such entity, the location of the
1935 /// type that will have pointer type.
1936 ///
1937 /// \param Entity The name of the entity that involves the pointer
1938 /// type, if known.
1939 ///
1940 /// \returns A suitable pointer type, if there are no
1941 /// errors. Otherwise, returns a NULL type.
1943  SourceLocation Loc, DeclarationName Entity) {
1944  if (T->isReferenceType()) {
1945  // C++ 8.3.2p4: There shall be no ... pointers to references ...
1946  Diag(Loc, diag::err_illegal_decl_pointer_to_reference)
1947  << getPrintableNameForEntity(Entity) << T;
1948  return QualType();
1949  }
1950 
1951  if (T->isFunctionType() && getLangOpts().OpenCL) {
1952  Diag(Loc, diag::err_opencl_function_pointer);
1953  return QualType();
1954  }
1955 
1956  if (checkQualifiedFunction(*this, T, Loc, QFK_Pointer))
1957  return QualType();
1958 
1959  assert(!T->isObjCObjectType() && "Should build ObjCObjectPointerType");
1960 
1961  // In ARC, it is forbidden to build pointers to unqualified pointers.
1962  if (getLangOpts().ObjCAutoRefCount)
1963  T = inferARCLifetimeForPointee(*this, T, Loc, /*reference*/ false);
1964 
1965  // Build the pointer type.
1966  return Context.getPointerType(T);
1967 }
1968 
1969 /// Build a reference type.
1970 ///
1971 /// \param T The type to which we'll be building a reference.
1972 ///
1973 /// \param Loc The location of the entity whose type involves this
1974 /// reference type or, if there is no such entity, the location of the
1975 /// type that will have reference type.
1976 ///
1977 /// \param Entity The name of the entity that involves the reference
1978 /// type, if known.
1979 ///
1980 /// \returns A suitable reference type, if there are no
1981 /// errors. Otherwise, returns a NULL type.
1983  SourceLocation Loc,
1984  DeclarationName Entity) {
1985  assert(Context.getCanonicalType(T) != Context.OverloadTy &&
1986  "Unresolved overloaded function type");
1987 
1988  // C++0x [dcl.ref]p6:
1989  // If a typedef (7.1.3), a type template-parameter (14.3.1), or a
1990  // decltype-specifier (7.1.6.2) denotes a type TR that is a reference to a
1991  // type T, an attempt to create the type "lvalue reference to cv TR" creates
1992  // the type "lvalue reference to T", while an attempt to create the type
1993  // "rvalue reference to cv TR" creates the type TR.
1994  bool LValueRef = SpelledAsLValue || T->getAs<LValueReferenceType>();
1995 
1996  // C++ [dcl.ref]p4: There shall be no references to references.
1997  //
1998  // According to C++ DR 106, references to references are only
1999  // diagnosed when they are written directly (e.g., "int & &"),
2000  // but not when they happen via a typedef:
2001  //
2002  // typedef int& intref;
2003  // typedef intref& intref2;
2004  //
2005  // Parser::ParseDeclaratorInternal diagnoses the case where
2006  // references are written directly; here, we handle the
2007  // collapsing of references-to-references as described in C++0x.
2008  // DR 106 and 540 introduce reference-collapsing into C++98/03.
2009 
2010  // C++ [dcl.ref]p1:
2011  // A declarator that specifies the type "reference to cv void"
2012  // is ill-formed.
2013  if (T->isVoidType()) {
2014  Diag(Loc, diag::err_reference_to_void);
2015  return QualType();
2016  }
2017 
2018  if (checkQualifiedFunction(*this, T, Loc, QFK_Reference))
2019  return QualType();
2020 
2021  // In ARC, it is forbidden to build references to unqualified pointers.
2022  if (getLangOpts().ObjCAutoRefCount)
2023  T = inferARCLifetimeForPointee(*this, T, Loc, /*reference*/ true);
2024 
2025  // Handle restrict on references.
2026  if (LValueRef)
2027  return Context.getLValueReferenceType(T, SpelledAsLValue);
2028  return Context.getRValueReferenceType(T);
2029 }
2030 
2031 /// Build a Read-only Pipe type.
2032 ///
2033 /// \param T The type to which we'll be building a Pipe.
2034 ///
2035 /// \param Loc We do not use it for now.
2036 ///
2037 /// \returns A suitable pipe type, if there are no errors. Otherwise, returns a
2038 /// NULL type.
2040  return Context.getReadPipeType(T);
2041 }
2042 
2043 /// Build a Write-only Pipe type.
2044 ///
2045 /// \param T The type to which we'll be building a Pipe.
2046 ///
2047 /// \param Loc We do not use it for now.
2048 ///
2049 /// \returns A suitable pipe type, if there are no errors. Otherwise, returns a
2050 /// NULL type.
2052  return Context.getWritePipeType(T);
2053 }
2054 
2055 /// Check whether the specified array size makes the array type a VLA. If so,
2056 /// return true, if not, return the size of the array in SizeVal.
2057 static bool isArraySizeVLA(Sema &S, Expr *ArraySize, llvm::APSInt &SizeVal) {
2058  // If the size is an ICE, it certainly isn't a VLA. If we're in a GNU mode
2059  // (like gnu99, but not c99) accept any evaluatable value as an extension.
2060  class VLADiagnoser : public Sema::VerifyICEDiagnoser {
2061  public:
2062  VLADiagnoser() : Sema::VerifyICEDiagnoser(true) {}
2063 
2064  void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
2065  }
2066 
2067  void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR) override {
2068  S.Diag(Loc, diag::ext_vla_folded_to_constant) << SR;
2069  }
2070  } Diagnoser;
2071 
2072  return S.VerifyIntegerConstantExpression(ArraySize, &SizeVal, Diagnoser,
2073  S.LangOpts.GNUMode ||
2074  S.LangOpts.OpenCL).isInvalid();
2075 }
2076 
2077 /// Build an array type.
2078 ///
2079 /// \param T The type of each element in the array.
2080 ///
2081 /// \param ASM C99 array size modifier (e.g., '*', 'static').
2082 ///
2083 /// \param ArraySize Expression describing the size of the array.
2084 ///
2085 /// \param Brackets The range from the opening '[' to the closing ']'.
2086 ///
2087 /// \param Entity The name of the entity that involves the array
2088 /// type, if known.
2089 ///
2090 /// \returns A suitable array type, if there are no errors. Otherwise,
2091 /// returns a NULL type.
2093  Expr *ArraySize, unsigned Quals,
2094  SourceRange Brackets, DeclarationName Entity) {
2095 
2096  SourceLocation Loc = Brackets.getBegin();
2097  if (getLangOpts().CPlusPlus) {
2098  // C++ [dcl.array]p1:
2099  // T is called the array element type; this type shall not be a reference
2100  // type, the (possibly cv-qualified) type void, a function type or an
2101  // abstract class type.
2102  //
2103  // C++ [dcl.array]p3:
2104  // When several "array of" specifications are adjacent, [...] only the
2105  // first of the constant expressions that specify the bounds of the arrays
2106  // may be omitted.
2107  //
2108  // Note: function types are handled in the common path with C.
2109  if (T->isReferenceType()) {
2110  Diag(Loc, diag::err_illegal_decl_array_of_references)
2111  << getPrintableNameForEntity(Entity) << T;
2112  return QualType();
2113  }
2114 
2115  if (T->isVoidType() || T->isIncompleteArrayType()) {
2116  Diag(Loc, diag::err_illegal_decl_array_incomplete_type) << T;
2117  return QualType();
2118  }
2119 
2120  if (RequireNonAbstractType(Brackets.getBegin(), T,
2121  diag::err_array_of_abstract_type))
2122  return QualType();
2123 
2124  // Mentioning a member pointer type for an array type causes us to lock in
2125  // an inheritance model, even if it's inside an unused typedef.
2126  if (Context.getTargetInfo().getCXXABI().isMicrosoft())
2127  if (const MemberPointerType *MPTy = T->getAs<MemberPointerType>())
2128  if (!MPTy->getClass()->isDependentType())
2129  (void)isCompleteType(Loc, T);
2130 
2131  } else {
2132  // C99 6.7.5.2p1: If the element type is an incomplete or function type,
2133  // reject it (e.g. void ary[7], struct foo ary[7], void ary[7]())
2134  if (RequireCompleteType(Loc, T,
2135  diag::err_illegal_decl_array_incomplete_type))
2136  return QualType();
2137  }
2138 
2139  if (T->isFunctionType()) {
2140  Diag(Loc, diag::err_illegal_decl_array_of_functions)
2141  << getPrintableNameForEntity(Entity) << T;
2142  return QualType();
2143  }
2144 
2145  if (const RecordType *EltTy = T->getAs<RecordType>()) {
2146  // If the element type is a struct or union that contains a variadic
2147  // array, accept it as a GNU extension: C99 6.7.2.1p2.
2148  if (EltTy->getDecl()->hasFlexibleArrayMember())
2149  Diag(Loc, diag::ext_flexible_array_in_array) << T;
2150  } else if (T->isObjCObjectType()) {
2151  Diag(Loc, diag::err_objc_array_of_interfaces) << T;
2152  return QualType();
2153  }
2154 
2155  // Do placeholder conversions on the array size expression.
2156  if (ArraySize && ArraySize->hasPlaceholderType()) {
2157  ExprResult Result = CheckPlaceholderExpr(ArraySize);
2158  if (Result.isInvalid()) return QualType();
2159  ArraySize = Result.get();
2160  }
2161 
2162  // Do lvalue-to-rvalue conversions on the array size expression.
2163  if (ArraySize && !ArraySize->isRValue()) {
2164  ExprResult Result = DefaultLvalueConversion(ArraySize);
2165  if (Result.isInvalid())
2166  return QualType();
2167 
2168  ArraySize = Result.get();
2169  }
2170 
2171  // C99 6.7.5.2p1: The size expression shall have integer type.
2172  // C++11 allows contextual conversions to such types.
2173  if (!getLangOpts().CPlusPlus11 &&
2174  ArraySize && !ArraySize->isTypeDependent() &&
2175  !ArraySize->getType()->isIntegralOrUnscopedEnumerationType()) {
2176  Diag(ArraySize->getBeginLoc(), diag::err_array_size_non_int)
2177  << ArraySize->getType() << ArraySize->getSourceRange();
2178  return QualType();
2179  }
2180 
2181  llvm::APSInt ConstVal(Context.getTypeSize(Context.getSizeType()));
2182  if (!ArraySize) {
2183  if (ASM == ArrayType::Star)
2184  T = Context.getVariableArrayType(T, nullptr, ASM, Quals, Brackets);
2185  else
2186  T = Context.getIncompleteArrayType(T, ASM, Quals);
2187  } else if (ArraySize->isTypeDependent() || ArraySize->isValueDependent()) {
2188  T = Context.getDependentSizedArrayType(T, ArraySize, ASM, Quals, Brackets);
2189  } else if ((!T->isDependentType() && !T->isIncompleteType() &&
2190  !T->isConstantSizeType()) ||
2191  isArraySizeVLA(*this, ArraySize, ConstVal)) {
2192  // Even in C++11, don't allow contextual conversions in the array bound
2193  // of a VLA.
2194  if (getLangOpts().CPlusPlus11 &&
2195  !ArraySize->getType()->isIntegralOrUnscopedEnumerationType()) {
2196  Diag(ArraySize->getBeginLoc(), diag::err_array_size_non_int)
2197  << ArraySize->getType() << ArraySize->getSourceRange();
2198  return QualType();
2199  }
2200 
2201  // C99: an array with an element type that has a non-constant-size is a VLA.
2202  // C99: an array with a non-ICE size is a VLA. We accept any expression
2203  // that we can fold to a non-zero positive value as an extension.
2204  T = Context.getVariableArrayType(T, ArraySize, ASM, Quals, Brackets);
2205  } else {
2206  // C99 6.7.5.2p1: If the expression is a constant expression, it shall
2207  // have a value greater than zero.
2208  if (ConstVal.isSigned() && ConstVal.isNegative()) {
2209  if (Entity)
2210  Diag(ArraySize->getBeginLoc(), diag::err_decl_negative_array_size)
2211  << getPrintableNameForEntity(Entity) << ArraySize->getSourceRange();
2212  else
2213  Diag(ArraySize->getBeginLoc(), diag::err_typecheck_negative_array_size)
2214  << ArraySize->getSourceRange();
2215  return QualType();
2216  }
2217  if (ConstVal == 0) {
2218  // GCC accepts zero sized static arrays. We allow them when
2219  // we're not in a SFINAE context.
2220  Diag(ArraySize->getBeginLoc(), isSFINAEContext()
2221  ? diag::err_typecheck_zero_array_size
2222  : diag::ext_typecheck_zero_array_size)
2223  << ArraySize->getSourceRange();
2224 
2225  if (ASM == ArrayType::Static) {
2226  Diag(ArraySize->getBeginLoc(),
2227  diag::warn_typecheck_zero_static_array_size)
2228  << ArraySize->getSourceRange();
2229  ASM = ArrayType::Normal;
2230  }
2231  } else if (!T->isDependentType() && !T->isVariablyModifiedType() &&
2232  !T->isIncompleteType() && !T->isUndeducedType()) {
2233  // Is the array too large?
2234  unsigned ActiveSizeBits
2235  = ConstantArrayType::getNumAddressingBits(Context, T, ConstVal);
2236  if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
2237  Diag(ArraySize->getBeginLoc(), diag::err_array_too_large)
2238  << ConstVal.toString(10) << ArraySize->getSourceRange();
2239  return QualType();
2240  }
2241  }
2242 
2243  T = Context.getConstantArrayType(T, ConstVal, ASM, Quals);
2244  }
2245 
2246  // OpenCL v1.2 s6.9.d: variable length arrays are not supported.
2247  if (getLangOpts().OpenCL && T->isVariableArrayType()) {
2248  Diag(Loc, diag::err_opencl_vla);
2249  return QualType();
2250  }
2251 
2252  if (T->isVariableArrayType() && !Context.getTargetInfo().isVLASupported()) {
2253  if (getLangOpts().CUDA) {
2254  // CUDA device code doesn't support VLAs.
2255  CUDADiagIfDeviceCode(Loc, diag::err_cuda_vla) << CurrentCUDATarget();
2256  } else if (!getLangOpts().OpenMP ||
2257  shouldDiagnoseTargetSupportFromOpenMP()) {
2258  // Some targets don't support VLAs.
2259  Diag(Loc, diag::err_vla_unsupported);
2260  return QualType();
2261  }
2262  }
2263 
2264  // If this is not C99, extwarn about VLA's and C99 array size modifiers.
2265  if (!getLangOpts().C99) {
2266  if (T->isVariableArrayType()) {
2267  // Prohibit the use of VLAs during template argument deduction.
2268  if (isSFINAEContext()) {
2269  Diag(Loc, diag::err_vla_in_sfinae);
2270  return QualType();
2271  }
2272  // Just extwarn about VLAs.
2273  else
2274  Diag(Loc, diag::ext_vla);
2275  } else if (ASM != ArrayType::Normal || Quals != 0)
2276  Diag(Loc,
2277  getLangOpts().CPlusPlus? diag::err_c99_array_usage_cxx
2278  : diag::ext_c99_array_usage) << ASM;
2279  }
2280 
2281  if (T->isVariableArrayType()) {
2282  // Warn about VLAs for -Wvla.
2283  Diag(Loc, diag::warn_vla_used);
2284  }
2285 
2286  // OpenCL v2.0 s6.12.5 - Arrays of blocks are not supported.
2287  // OpenCL v2.0 s6.16.13.1 - Arrays of pipe type are not supported.
2288  // OpenCL v2.0 s6.9.b - Arrays of image/sampler type are not supported.
2289  if (getLangOpts().OpenCL) {
2290  const QualType ArrType = Context.getBaseElementType(T);
2291  if (ArrType->isBlockPointerType() || ArrType->isPipeType() ||
2292  ArrType->isSamplerT() || ArrType->isImageType()) {
2293  Diag(Loc, diag::err_opencl_invalid_type_array) << ArrType;
2294  return QualType();
2295  }
2296  }
2297 
2298  return T;
2299 }
2300 
2302  SourceLocation AttrLoc) {
2303  // The base type must be integer (not Boolean or enumeration) or float, and
2304  // can't already be a vector.
2305  if (!CurType->isDependentType() &&
2306  (!CurType->isBuiltinType() || CurType->isBooleanType() ||
2307  (!CurType->isIntegerType() && !CurType->isRealFloatingType()))) {
2308  Diag(AttrLoc, diag::err_attribute_invalid_vector_type) << CurType;
2309  return QualType();
2310  }
2311 
2312  if (SizeExpr->isTypeDependent() || SizeExpr->isValueDependent())
2313  return Context.getDependentVectorType(CurType, SizeExpr, AttrLoc,
2315 
2316  llvm::APSInt VecSize(32);
2317  if (!SizeExpr->isIntegerConstantExpr(VecSize, Context)) {
2318  Diag(AttrLoc, diag::err_attribute_argument_type)
2319  << "vector_size" << AANT_ArgumentIntegerConstant
2320  << SizeExpr->getSourceRange();
2321  return QualType();
2322  }
2323 
2324  if (CurType->isDependentType())
2325  return Context.getDependentVectorType(CurType, SizeExpr, AttrLoc,
2327 
2328  unsigned VectorSize = static_cast<unsigned>(VecSize.getZExtValue() * 8);
2329  unsigned TypeSize = static_cast<unsigned>(Context.getTypeSize(CurType));
2330 
2331  if (VectorSize == 0) {
2332  Diag(AttrLoc, diag::err_attribute_zero_size) << SizeExpr->getSourceRange();
2333  return QualType();
2334  }
2335 
2336  // vecSize is specified in bytes - convert to bits.
2337  if (VectorSize % TypeSize) {
2338  Diag(AttrLoc, diag::err_attribute_invalid_size)
2339  << SizeExpr->getSourceRange();
2340  return QualType();
2341  }
2342 
2343  if (VectorType::isVectorSizeTooLarge(VectorSize / TypeSize)) {
2344  Diag(AttrLoc, diag::err_attribute_size_too_large)
2345  << SizeExpr->getSourceRange();
2346  return QualType();
2347  }
2348 
2349  return Context.getVectorType(CurType, VectorSize / TypeSize,
2351 }
2352 
2353 /// Build an ext-vector type.
2354 ///
2355 /// Run the required checks for the extended vector type.
2357  SourceLocation AttrLoc) {
2358  // Unlike gcc's vector_size attribute, we do not allow vectors to be defined
2359  // in conjunction with complex types (pointers, arrays, functions, etc.).
2360  //
2361  // Additionally, OpenCL prohibits vectors of booleans (they're considered a
2362  // reserved data type under OpenCL v2.0 s6.1.4), we don't support selects
2363  // on bitvectors, and we have no well-defined ABI for bitvectors, so vectors
2364  // of bool aren't allowed.
2365  if ((!T->isDependentType() && !T->isIntegerType() &&
2366  !T->isRealFloatingType()) ||
2367  T->isBooleanType()) {
2368  Diag(AttrLoc, diag::err_attribute_invalid_vector_type) << T;
2369  return QualType();
2370  }
2371 
2372  if (!ArraySize->isTypeDependent() && !ArraySize->isValueDependent()) {
2373  llvm::APSInt vecSize(32);
2374  if (!ArraySize->isIntegerConstantExpr(vecSize, Context)) {
2375  Diag(AttrLoc, diag::err_attribute_argument_type)
2376  << "ext_vector_type" << AANT_ArgumentIntegerConstant
2377  << ArraySize->getSourceRange();
2378  return QualType();
2379  }
2380 
2381  // Unlike gcc's vector_size attribute, the size is specified as the
2382  // number of elements, not the number of bytes.
2383  unsigned vectorSize = static_cast<unsigned>(vecSize.getZExtValue());
2384 
2385  if (vectorSize == 0) {
2386  Diag(AttrLoc, diag::err_attribute_zero_size)
2387  << ArraySize->getSourceRange();
2388  return QualType();
2389  }
2390 
2391  if (VectorType::isVectorSizeTooLarge(vectorSize)) {
2392  Diag(AttrLoc, diag::err_attribute_size_too_large)
2393  << ArraySize->getSourceRange();
2394  return QualType();
2395  }
2396 
2397  return Context.getExtVectorType(T, vectorSize);
2398  }
2399 
2400  return Context.getDependentSizedExtVectorType(T, ArraySize, AttrLoc);
2401 }
2402 
2404  if (T->isArrayType() || T->isFunctionType()) {
2405  Diag(Loc, diag::err_func_returning_array_function)
2406  << T->isFunctionType() << T;
2407  return true;
2408  }
2409 
2410  // Functions cannot return half FP.
2411  if (T->isHalfType() && !getLangOpts().HalfArgsAndReturns) {
2412  Diag(Loc, diag::err_parameters_retval_cannot_have_fp16_type) << 1 <<
2413  FixItHint::CreateInsertion(Loc, "*");
2414  return true;
2415  }
2416 
2417  // Methods cannot return interface types. All ObjC objects are
2418  // passed by reference.
2419  if (T->isObjCObjectType()) {
2420  Diag(Loc, diag::err_object_cannot_be_passed_returned_by_value)
2421  << 0 << T << FixItHint::CreateInsertion(Loc, "*");
2422  return true;
2423  }
2424 
2425  return false;
2426 }
2427 
2428 /// Check the extended parameter information. Most of the necessary
2429 /// checking should occur when applying the parameter attribute; the
2430 /// only other checks required are positional restrictions.
2433  llvm::function_ref<SourceLocation(unsigned)> getParamLoc) {
2434  assert(EPI.ExtParameterInfos && "shouldn't get here without param infos");
2435 
2436  bool hasCheckedSwiftCall = false;
2437  auto checkForSwiftCC = [&](unsigned paramIndex) {
2438  // Only do this once.
2439  if (hasCheckedSwiftCall) return;
2440  hasCheckedSwiftCall = true;
2441  if (EPI.ExtInfo.getCC() == CC_Swift) return;
2442  S.Diag(getParamLoc(paramIndex), diag::err_swift_param_attr_not_swiftcall)
2443  << getParameterABISpelling(EPI.ExtParameterInfos[paramIndex].getABI());
2444  };
2445 
2446  for (size_t paramIndex = 0, numParams = paramTypes.size();
2447  paramIndex != numParams; ++paramIndex) {
2448  switch (EPI.ExtParameterInfos[paramIndex].getABI()) {
2449  // Nothing interesting to check for orindary-ABI parameters.
2451  continue;
2452 
2453  // swift_indirect_result parameters must be a prefix of the function
2454  // arguments.
2456  checkForSwiftCC(paramIndex);
2457  if (paramIndex != 0 &&
2458  EPI.ExtParameterInfos[paramIndex - 1].getABI()
2460  S.Diag(getParamLoc(paramIndex),
2461  diag::err_swift_indirect_result_not_first);
2462  }
2463  continue;
2464 
2466  checkForSwiftCC(paramIndex);
2467  continue;
2468 
2469  // swift_error parameters must be preceded by a swift_context parameter.
2471  checkForSwiftCC(paramIndex);
2472  if (paramIndex == 0 ||
2473  EPI.ExtParameterInfos[paramIndex - 1].getABI() !=
2475  S.Diag(getParamLoc(paramIndex),
2476  diag::err_swift_error_result_not_after_swift_context);
2477  }
2478  continue;
2479  }
2480  llvm_unreachable("bad ABI kind");
2481  }
2482 }
2483 
2485  MutableArrayRef<QualType> ParamTypes,
2486  SourceLocation Loc, DeclarationName Entity,
2487  const FunctionProtoType::ExtProtoInfo &EPI) {
2488  bool Invalid = false;
2489 
2490  Invalid |= CheckFunctionReturnType(T, Loc);
2491 
2492  for (unsigned Idx = 0, Cnt = ParamTypes.size(); Idx < Cnt; ++Idx) {
2493  // FIXME: Loc is too inprecise here, should use proper locations for args.
2494  QualType ParamType = Context.getAdjustedParameterType(ParamTypes[Idx]);
2495  if (ParamType->isVoidType()) {
2496  Diag(Loc, diag::err_param_with_void_type);
2497  Invalid = true;
2498  } else if (ParamType->isHalfType() && !getLangOpts().HalfArgsAndReturns) {
2499  // Disallow half FP arguments.
2500  Diag(Loc, diag::err_parameters_retval_cannot_have_fp16_type) << 0 <<
2501  FixItHint::CreateInsertion(Loc, "*");
2502  Invalid = true;
2503  }
2504 
2505  ParamTypes[Idx] = ParamType;
2506  }
2507 
2508  if (EPI.ExtParameterInfos) {
2509  checkExtParameterInfos(*this, ParamTypes, EPI,
2510  [=](unsigned i) { return Loc; });
2511  }
2512 
2513  if (EPI.ExtInfo.getProducesResult()) {
2514  // This is just a warning, so we can't fail to build if we see it.
2515  checkNSReturnsRetainedReturnType(Loc, T);
2516  }
2517 
2518  if (Invalid)
2519  return QualType();
2520 
2521  return Context.getFunctionType(T, ParamTypes, EPI);
2522 }
2523 
2524 /// Build a member pointer type \c T Class::*.
2525 ///
2526 /// \param T the type to which the member pointer refers.
2527 /// \param Class the class type into which the member pointer points.
2528 /// \param Loc the location where this type begins
2529 /// \param Entity the name of the entity that will have this member pointer type
2530 ///
2531 /// \returns a member pointer type, if successful, or a NULL type if there was
2532 /// an error.
2534  SourceLocation Loc,
2535  DeclarationName Entity) {
2536  // Verify that we're not building a pointer to pointer to function with
2537  // exception specification.
2538  if (CheckDistantExceptionSpec(T)) {
2539  Diag(Loc, diag::err_distant_exception_spec);
2540  return QualType();
2541  }
2542 
2543  // C++ 8.3.3p3: A pointer to member shall not point to ... a member
2544  // with reference type, or "cv void."
2545  if (T->isReferenceType()) {
2546  Diag(Loc, diag::err_illegal_decl_mempointer_to_reference)
2547  << getPrintableNameForEntity(Entity) << T;
2548  return QualType();
2549  }
2550 
2551  if (T->isVoidType()) {
2552  Diag(Loc, diag::err_illegal_decl_mempointer_to_void)
2553  << getPrintableNameForEntity(Entity);
2554  return QualType();
2555  }
2556 
2557  if (!Class->isDependentType() && !Class->isRecordType()) {
2558  Diag(Loc, diag::err_mempointer_in_nonclass_type) << Class;
2559  return QualType();
2560  }
2561 
2562  // Adjust the default free function calling convention to the default method
2563  // calling convention.
2564  bool IsCtorOrDtor =
2567  if (T->isFunctionType())
2568  adjustMemberFunctionCC(T, /*IsStatic=*/false, IsCtorOrDtor, Loc);
2569 
2570  return Context.getMemberPointerType(T, Class.getTypePtr());
2571 }
2572 
2573 /// Build a block pointer type.
2574 ///
2575 /// \param T The type to which we'll be building a block pointer.
2576 ///
2577 /// \param Loc The source location, used for diagnostics.
2578 ///
2579 /// \param Entity The name of the entity that involves the block pointer
2580 /// type, if known.
2581 ///
2582 /// \returns A suitable block pointer type, if there are no
2583 /// errors. Otherwise, returns a NULL type.
2585  SourceLocation Loc,
2586  DeclarationName Entity) {
2587  if (!T->isFunctionType()) {
2588  Diag(Loc, diag::err_nonfunction_block_type);
2589  return QualType();
2590  }
2591 
2592  if (checkQualifiedFunction(*this, T, Loc, QFK_BlockPointer))
2593  return QualType();
2594 
2595  return Context.getBlockPointerType(T);
2596 }
2597 
2599  QualType QT = Ty.get();
2600  if (QT.isNull()) {
2601  if (TInfo) *TInfo = nullptr;
2602  return QualType();
2603  }
2604 
2605  TypeSourceInfo *DI = nullptr;
2606  if (const LocInfoType *LIT = dyn_cast<LocInfoType>(QT)) {
2607  QT = LIT->getType();
2608  DI = LIT->getTypeSourceInfo();
2609  }
2610 
2611  if (TInfo) *TInfo = DI;
2612  return QT;
2613 }
2614 
2615 static void transferARCOwnershipToDeclaratorChunk(TypeProcessingState &state,
2616  Qualifiers::ObjCLifetime ownership,
2617  unsigned chunkIndex);
2618 
2619 /// Given that this is the declaration of a parameter under ARC,
2620 /// attempt to infer attributes and such for pointer-to-whatever
2621 /// types.
2622 static void inferARCWriteback(TypeProcessingState &state,
2623  QualType &declSpecType) {
2624  Sema &S = state.getSema();
2625  Declarator &declarator = state.getDeclarator();
2626 
2627  // TODO: should we care about decl qualifiers?
2628 
2629  // Check whether the declarator has the expected form. We walk
2630  // from the inside out in order to make the block logic work.
2631  unsigned outermostPointerIndex = 0;
2632  bool isBlockPointer = false;
2633  unsigned numPointers = 0;
2634  for (unsigned i = 0, e = declarator.getNumTypeObjects(); i != e; ++i) {
2635  unsigned chunkIndex = i;
2636  DeclaratorChunk &chunk = declarator.getTypeObject(chunkIndex);
2637  switch (chunk.Kind) {
2639  // Ignore parens.
2640  break;
2641 
2644  // Count the number of pointers. Treat references
2645  // interchangeably as pointers; if they're mis-ordered, normal
2646  // type building will discover that.
2647  outermostPointerIndex = chunkIndex;
2648  numPointers++;
2649  break;
2650 
2652  // If we have a pointer to block pointer, that's an acceptable
2653  // indirect reference; anything else is not an application of
2654  // the rules.
2655  if (numPointers != 1) return;
2656  numPointers++;
2657  outermostPointerIndex = chunkIndex;
2658  isBlockPointer = true;
2659 
2660  // We don't care about pointer structure in return values here.
2661  goto done;
2662 
2663  case DeclaratorChunk::Array: // suppress if written (id[])?
2666  case DeclaratorChunk::Pipe:
2667  return;
2668  }
2669  }
2670  done:
2671 
2672  // If we have *one* pointer, then we want to throw the qualifier on
2673  // the declaration-specifiers, which means that it needs to be a
2674  // retainable object type.
2675  if (numPointers == 1) {
2676  // If it's not a retainable object type, the rule doesn't apply.
2677  if (!declSpecType->isObjCRetainableType()) return;
2678 
2679  // If it already has lifetime, don't do anything.
2680  if (declSpecType.getObjCLifetime()) return;
2681 
2682  // Otherwise, modify the type in-place.
2683  Qualifiers qs;
2684 
2685  if (declSpecType->isObjCARCImplicitlyUnretainedType())
2687  else
2689  declSpecType = S.Context.getQualifiedType(declSpecType, qs);
2690 
2691  // If we have *two* pointers, then we want to throw the qualifier on
2692  // the outermost pointer.
2693  } else if (numPointers == 2) {
2694  // If we don't have a block pointer, we need to check whether the
2695  // declaration-specifiers gave us something that will turn into a
2696  // retainable object pointer after we slap the first pointer on it.
2697  if (!isBlockPointer && !declSpecType->isObjCObjectType())
2698  return;
2699 
2700  // Look for an explicit lifetime attribute there.
2701  DeclaratorChunk &chunk = declarator.getTypeObject(outermostPointerIndex);
2702  if (chunk.Kind != DeclaratorChunk::Pointer &&
2704  return;
2705  for (const ParsedAttr &AL : chunk.getAttrs())
2706  if (AL.getKind() == ParsedAttr::AT_ObjCOwnership)
2707  return;
2708 
2710  outermostPointerIndex);
2711 
2712  // Any other number of pointers/references does not trigger the rule.
2713  } else return;
2714 
2715  // TODO: mark whether we did this inference?
2716 }
2717 
2718 void Sema::diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
2719  SourceLocation FallbackLoc,
2720  SourceLocation ConstQualLoc,
2721  SourceLocation VolatileQualLoc,
2722  SourceLocation RestrictQualLoc,
2723  SourceLocation AtomicQualLoc,
2724  SourceLocation UnalignedQualLoc) {
2725  if (!Quals)
2726  return;
2727 
2728  struct Qual {
2729  const char *Name;
2730  unsigned Mask;
2731  SourceLocation Loc;
2732  } const QualKinds[5] = {
2733  { "const", DeclSpec::TQ_const, ConstQualLoc },
2734  { "volatile", DeclSpec::TQ_volatile, VolatileQualLoc },
2735  { "restrict", DeclSpec::TQ_restrict, RestrictQualLoc },
2736  { "__unaligned", DeclSpec::TQ_unaligned, UnalignedQualLoc },
2737  { "_Atomic", DeclSpec::TQ_atomic, AtomicQualLoc }
2738  };
2739 
2740  SmallString<32> QualStr;
2741  unsigned NumQuals = 0;
2742  SourceLocation Loc;
2743  FixItHint FixIts[5];
2744 
2745  // Build a string naming the redundant qualifiers.
2746  for (auto &E : QualKinds) {
2747  if (Quals & E.Mask) {
2748  if (!QualStr.empty()) QualStr += ' ';
2749  QualStr += E.Name;
2750 
2751  // If we have a location for the qualifier, offer a fixit.
2752  SourceLocation QualLoc = E.Loc;
2753  if (QualLoc.isValid()) {
2754  FixIts[NumQuals] = FixItHint::CreateRemoval(QualLoc);
2755  if (Loc.isInvalid() ||
2756  getSourceManager().isBeforeInTranslationUnit(QualLoc, Loc))
2757  Loc = QualLoc;
2758  }
2759 
2760  ++NumQuals;
2761  }
2762  }
2763 
2764  Diag(Loc.isInvalid() ? FallbackLoc : Loc, DiagID)
2765  << QualStr << NumQuals << FixIts[0] << FixIts[1] << FixIts[2] << FixIts[3];
2766 }
2767 
2768 // Diagnose pointless type qualifiers on the return type of a function.
2770  Declarator &D,
2771  unsigned FunctionChunkIndex) {
2772  if (D.getTypeObject(FunctionChunkIndex).Fun.hasTrailingReturnType()) {
2773  // FIXME: TypeSourceInfo doesn't preserve location information for
2774  // qualifiers.
2775  S.diagnoseIgnoredQualifiers(diag::warn_qual_return_type,
2776  RetTy.getLocalCVRQualifiers(),
2777  D.getIdentifierLoc());
2778  return;
2779  }
2780 
2781  for (unsigned OuterChunkIndex = FunctionChunkIndex + 1,
2782  End = D.getNumTypeObjects();
2783  OuterChunkIndex != End; ++OuterChunkIndex) {
2784  DeclaratorChunk &OuterChunk = D.getTypeObject(OuterChunkIndex);
2785  switch (OuterChunk.Kind) {
2787  continue;
2788 
2789  case DeclaratorChunk::Pointer: {
2790  DeclaratorChunk::PointerTypeInfo &PTI = OuterChunk.Ptr;
2792  diag::warn_qual_return_type,
2793  PTI.TypeQuals,
2794  SourceLocation(),
2800  return;
2801  }
2802 
2808  case DeclaratorChunk::Pipe:
2809  // FIXME: We can't currently provide an accurate source location and a
2810  // fix-it hint for these.
2811  unsigned AtomicQual = RetTy->isAtomicType() ? DeclSpec::TQ_atomic : 0;
2812  S.diagnoseIgnoredQualifiers(diag::warn_qual_return_type,
2813  RetTy.getCVRQualifiers() | AtomicQual,
2814  D.getIdentifierLoc());
2815  return;
2816  }
2817 
2818  llvm_unreachable("unknown declarator chunk kind");
2819  }
2820 
2821  // If the qualifiers come from a conversion function type, don't diagnose
2822  // them -- they're not necessarily redundant, since such a conversion
2823  // operator can be explicitly called as "x.operator const int()".
2825  return;
2826 
2827  // Just parens all the way out to the decl specifiers. Diagnose any qualifiers
2828  // which are present there.
2829  S.diagnoseIgnoredQualifiers(diag::warn_qual_return_type,
2831  D.getIdentifierLoc(),
2837 }
2838 
2839 static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
2840  TypeSourceInfo *&ReturnTypeInfo) {
2841  Sema &SemaRef = state.getSema();
2842  Declarator &D = state.getDeclarator();
2843  QualType T;
2844  ReturnTypeInfo = nullptr;
2845 
2846  // The TagDecl owned by the DeclSpec.
2847  TagDecl *OwnedTagDecl = nullptr;
2848 
2849  switch (D.getName().getKind()) {
2855  T = ConvertDeclSpecToType(state);
2856 
2857  if (!D.isInvalidType() && D.getDeclSpec().isTypeSpecOwned()) {
2858  OwnedTagDecl = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
2859  // Owned declaration is embedded in declarator.
2860  OwnedTagDecl->setEmbeddedInDeclarator(true);
2861  }
2862  break;
2863 
2867  // Constructors and destructors don't have return types. Use
2868  // "void" instead.
2869  T = SemaRef.Context.VoidTy;
2870  processTypeAttrs(state, T, TAL_DeclSpec,
2872  break;
2873 
2875  // Deduction guides have a trailing return type and no type in their
2876  // decl-specifier sequence. Use a placeholder return type for now.
2877  T = SemaRef.Context.DependentTy;
2878  break;
2879 
2881  // The result type of a conversion function is the type that it
2882  // converts to.
2884  &ReturnTypeInfo);
2885  break;
2886  }
2887 
2888  if (!D.getAttributes().empty())
2890 
2891  // C++11 [dcl.spec.auto]p5: reject 'auto' if it is not in an allowed context.
2892  if (DeducedType *Deduced = T->getContainedDeducedType()) {
2893  AutoType *Auto = dyn_cast<AutoType>(Deduced);
2894  int Error = -1;
2895 
2896  // Is this a 'auto' or 'decltype(auto)' type (as opposed to __auto_type or
2897  // class template argument deduction)?
2898  bool IsCXXAutoType =
2899  (Auto && Auto->getKeyword() != AutoTypeKeyword::GNUAutoType);
2900  bool IsDeducedReturnType = false;
2901 
2902  switch (D.getContext()) {
2904  // Declared return type of a lambda-declarator is implicit and is always
2905  // 'auto'.
2906  break;
2910  Error = 0;
2911  break;
2913  // In C++14, generic lambdas allow 'auto' in their parameters.
2914  if (!SemaRef.getLangOpts().CPlusPlus14 ||
2915  !Auto || Auto->getKeyword() != AutoTypeKeyword::Auto)
2916  Error = 16;
2917  else {
2918  // If auto is mentioned in a lambda parameter context, convert it to a
2919  // template parameter type.
2920  sema::LambdaScopeInfo *LSI = SemaRef.getCurLambda();
2921  assert(LSI && "No LambdaScopeInfo on the stack!");
2922  const unsigned TemplateParameterDepth = LSI->AutoTemplateParameterDepth;
2923  const unsigned AutoParameterPosition = LSI->AutoTemplateParams.size();
2924  const bool IsParameterPack = D.hasEllipsis();
2925 
2926  // Create the TemplateTypeParmDecl here to retrieve the corresponding
2927  // template parameter type. Template parameters are temporarily added
2928  // to the TU until the associated TemplateDecl is created.
2929  TemplateTypeParmDecl *CorrespondingTemplateParam =
2931  SemaRef.Context, SemaRef.Context.getTranslationUnitDecl(),
2932  /*KeyLoc*/ SourceLocation(), /*NameLoc*/ D.getBeginLoc(),
2933  TemplateParameterDepth, AutoParameterPosition,
2934  /*Identifier*/ nullptr, false, IsParameterPack);
2935  LSI->AutoTemplateParams.push_back(CorrespondingTemplateParam);
2936  // Replace the 'auto' in the function parameter with this invented
2937  // template type parameter.
2938  // FIXME: Retain some type sugar to indicate that this was written
2939  // as 'auto'.
2940  T = SemaRef.ReplaceAutoType(
2941  T, QualType(CorrespondingTemplateParam->getTypeForDecl(), 0));
2942  }
2943  break;
2947  break;
2948  bool Cxx = SemaRef.getLangOpts().CPlusPlus;
2949  switch (cast<TagDecl>(SemaRef.CurContext)->getTagKind()) {
2950  case TTK_Enum: llvm_unreachable("unhandled tag kind");
2951  case TTK_Struct: Error = Cxx ? 1 : 2; /* Struct member */ break;
2952  case TTK_Union: Error = Cxx ? 3 : 4; /* Union member */ break;
2953  case TTK_Class: Error = 5; /* Class member */ break;
2954  case TTK_Interface: Error = 6; /* Interface member */ break;
2955  }
2956  if (D.getDeclSpec().isFriendSpecified())
2957  Error = 20; // Friend type
2958  break;
2959  }
2962  Error = 7; // Exception declaration
2963  break;
2965  if (isa<DeducedTemplateSpecializationType>(Deduced))
2966  Error = 19; // Template parameter
2967  else if (!SemaRef.getLangOpts().CPlusPlus17)
2968  Error = 8; // Template parameter (until C++17)
2969  break;
2971  Error = 9; // Block literal
2972  break;
2974  // Within a template argument list, a deduced template specialization
2975  // type will be reinterpreted as a template template argument.
2976  if (isa<DeducedTemplateSpecializationType>(Deduced) &&
2977  !D.getNumTypeObjects() &&
2979  break;
2980  LLVM_FALLTHROUGH;
2982  Error = 10; // Template type argument
2983  break;
2986  Error = 12; // Type alias
2987  break;
2990  if (!SemaRef.getLangOpts().CPlusPlus14 || !IsCXXAutoType)
2991  Error = 13; // Function return type
2992  IsDeducedReturnType = true;
2993  break;
2995  if (!SemaRef.getLangOpts().CPlusPlus14 || !IsCXXAutoType)
2996  Error = 14; // conversion-type-id
2997  IsDeducedReturnType = true;
2998  break;
3000  if (isa<DeducedTemplateSpecializationType>(Deduced))
3001  break;
3002  LLVM_FALLTHROUGH;
3004  Error = 15; // Generic
3005  break;
3011  // FIXME: P0091R3 (erroneously) does not permit class template argument
3012  // deduction in conditions, for-init-statements, and other declarations
3013  // that are not simple-declarations.
3014  break;
3016  // FIXME: P0091R3 does not permit class template argument deduction here,
3017  // but we follow GCC and allow it anyway.
3018  if (!IsCXXAutoType && !isa<DeducedTemplateSpecializationType>(Deduced))
3019  Error = 17; // 'new' type
3020  break;
3022  Error = 18; // K&R function parameter
3023  break;
3024  }
3025 
3027  Error = 11;
3028 
3029  // In Objective-C it is an error to use 'auto' on a function declarator
3030  // (and everywhere for '__auto_type').
3031  if (D.isFunctionDeclarator() &&
3032  (!SemaRef.getLangOpts().CPlusPlus11 || !IsCXXAutoType))
3033  Error = 13;
3034 
3035  bool HaveTrailing = false;
3036 
3037  // C++11 [dcl.spec.auto]p2: 'auto' is always fine if the declarator
3038  // contains a trailing return type. That is only legal at the outermost
3039  // level. Check all declarator chunks (outermost first) anyway, to give
3040  // better diagnostics.
3041  // We don't support '__auto_type' with trailing return types.
3042  // FIXME: Should we only do this for 'auto' and not 'decltype(auto)'?
3043  if (SemaRef.getLangOpts().CPlusPlus11 && IsCXXAutoType &&
3044  D.hasTrailingReturnType()) {
3045  HaveTrailing = true;
3046  Error = -1;
3047  }
3048 
3049  SourceRange AutoRange = D.getDeclSpec().getTypeSpecTypeLoc();
3051  AutoRange = D.getName().getSourceRange();
3052 
3053  if (Error != -1) {
3054  unsigned Kind;
3055  if (Auto) {
3056  switch (Auto->getKeyword()) {
3057  case AutoTypeKeyword::Auto: Kind = 0; break;
3058  case AutoTypeKeyword::DecltypeAuto: Kind = 1; break;
3059  case AutoTypeKeyword::GNUAutoType: Kind = 2; break;
3060  }
3061  } else {
3062  assert(isa<DeducedTemplateSpecializationType>(Deduced) &&
3063  "unknown auto type");
3064  Kind = 3;
3065  }
3066 
3067  auto *DTST = dyn_cast<DeducedTemplateSpecializationType>(Deduced);
3068  TemplateName TN = DTST ? DTST->getTemplateName() : TemplateName();
3069 
3070  SemaRef.Diag(AutoRange.getBegin(), diag::err_auto_not_allowed)
3071  << Kind << Error << (int)SemaRef.getTemplateNameKindForDiagnostics(TN)
3072  << QualType(Deduced, 0) << AutoRange;
3073  if (auto *TD = TN.getAsTemplateDecl())
3074  SemaRef.Diag(TD->getLocation(), diag::note_template_decl_here);
3075 
3076  T = SemaRef.Context.IntTy;
3077  D.setInvalidType(true);
3078  } else if (!HaveTrailing &&
3080  // If there was a trailing return type, we already got
3081  // warn_cxx98_compat_trailing_return_type in the parser.
3082  SemaRef.Diag(AutoRange.getBegin(),
3083  D.getContext() ==
3085  ? diag::warn_cxx11_compat_generic_lambda
3086  : IsDeducedReturnType
3087  ? diag::warn_cxx11_compat_deduced_return_type
3088  : diag::warn_cxx98_compat_auto_type_specifier)
3089  << AutoRange;
3090  }
3091  }
3092 
3093  if (SemaRef.getLangOpts().CPlusPlus &&
3094  OwnedTagDecl && OwnedTagDecl->isCompleteDefinition()) {
3095  // Check the contexts where C++ forbids the declaration of a new class
3096  // or enumeration in a type-specifier-seq.
3097  unsigned DiagID = 0;
3098  switch (D.getContext()) {
3101  // Class and enumeration definitions are syntactically not allowed in
3102  // trailing return types.
3103  llvm_unreachable("parser should not have allowed this");
3104  break;
3112  // C++11 [dcl.type]p3:
3113  // A type-specifier-seq shall not define a class or enumeration unless
3114  // it appears in the type-id of an alias-declaration (7.1.3) that is not
3115  // the declaration of a template-declaration.
3117  break;
3119  DiagID = diag::err_type_defined_in_alias_template;
3120  break;
3130  DiagID = diag::err_type_defined_in_type_specifier;
3131  break;
3137  // C++ [dcl.fct]p6:
3138  // Types shall not be defined in return or parameter types.
3139  DiagID = diag::err_type_defined_in_param_type;
3140  break;
3142  // C++ 6.4p2:
3143  // The type-specifier-seq shall not contain typedef and shall not declare
3144  // a new class or enumeration.
3145  DiagID = diag::err_type_defined_in_condition;
3146  break;
3147  }
3148 
3149  if (DiagID != 0) {
3150  SemaRef.Diag(OwnedTagDecl->getLocation(), DiagID)
3151  << SemaRef.Context.getTypeDeclType(OwnedTagDecl);
3152  D.setInvalidType(true);
3153  }
3154  }
3155 
3156  assert(!T.isNull() && "This function should not return a null type");
3157  return T;
3158 }
3159 
3160 /// Produce an appropriate diagnostic for an ambiguity between a function
3161 /// declarator and a C++ direct-initializer.
3163  DeclaratorChunk &DeclType, QualType RT) {
3164  const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
3165  assert(FTI.isAmbiguous && "no direct-initializer / function ambiguity");
3166 
3167  // If the return type is void there is no ambiguity.
3168  if (RT->isVoidType())
3169  return;
3170 
3171  // An initializer for a non-class type can have at most one argument.
3172  if (!RT->isRecordType() && FTI.NumParams > 1)
3173  return;
3174 
3175  // An initializer for a reference must have exactly one argument.
3176  if (RT->isReferenceType() && FTI.NumParams != 1)
3177  return;
3178 
3179  // Only warn if this declarator is declaring a function at block scope, and
3180  // doesn't have a storage class (such as 'extern') specified.
3181  if (!D.isFunctionDeclarator() ||
3186  return;
3187 
3188  // Inside a condition, a direct initializer is not permitted. We allow one to
3189  // be parsed in order to give better diagnostics in condition parsing.
3191  return;
3192 
3193  SourceRange ParenRange(DeclType.Loc, DeclType.EndLoc);
3194 
3195  S.Diag(DeclType.Loc,
3196  FTI.NumParams ? diag::warn_parens_disambiguated_as_function_declaration
3197  : diag::warn_empty_parens_are_function_decl)
3198  << ParenRange;
3199 
3200  // If the declaration looks like:
3201  // T var1,
3202  // f();
3203  // and name lookup finds a function named 'f', then the ',' was
3204  // probably intended to be a ';'.
3205  if (!D.isFirstDeclarator() && D.getIdentifier()) {
3208  if (Comma.getFileID() != Name.getFileID() ||
3209  Comma.getSpellingLineNumber() != Name.getSpellingLineNumber()) {
3212  if (S.LookupName(Result, S.getCurScope()))
3213  S.Diag(D.getCommaLoc(), diag::note_empty_parens_function_call)
3215  << D.getIdentifier();
3216  Result.suppressDiagnostics();
3217  }
3218  }
3219 
3220  if (FTI.NumParams > 0) {
3221  // For a declaration with parameters, eg. "T var(T());", suggest adding
3222  // parens around the first parameter to turn the declaration into a
3223  // variable declaration.
3224  SourceRange Range = FTI.Params[0].Param->getSourceRange();
3225  SourceLocation B = Range.getBegin();
3226  SourceLocation E = S.getLocForEndOfToken(Range.getEnd());
3227  // FIXME: Maybe we should suggest adding braces instead of parens
3228  // in C++11 for classes that don't have an initializer_list constructor.
3229  S.Diag(B, diag::note_additional_parens_for_variable_declaration)
3230  << FixItHint::CreateInsertion(B, "(")
3231  << FixItHint::CreateInsertion(E, ")");
3232  } else {
3233  // For a declaration without parameters, eg. "T var();", suggest replacing
3234  // the parens with an initializer to turn the declaration into a variable
3235  // declaration.
3236  const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
3237 
3238  // Empty parens mean value-initialization, and no parens mean
3239  // default initialization. These are equivalent if the default
3240  // constructor is user-provided or if zero-initialization is a
3241  // no-op.
3242  if (RD && RD->hasDefinition() &&
3243  (RD->isEmpty() || RD->hasUserProvidedDefaultConstructor()))
3244  S.Diag(DeclType.Loc, diag::note_empty_parens_default_ctor)
3245  << FixItHint::CreateRemoval(ParenRange);
3246  else {
3247  std::string Init =
3248  S.getFixItZeroInitializerForType(RT, ParenRange.getBegin());
3249  if (Init.empty() && S.LangOpts.CPlusPlus11)
3250  Init = "{}";
3251  if (!Init.empty())
3252  S.Diag(DeclType.Loc, diag::note_empty_parens_zero_initialize)
3253  << FixItHint::CreateReplacement(ParenRange, Init);
3254  }
3255  }
3256 }
3257 
3258 /// Produce an appropriate diagnostic for a declarator with top-level
3259 /// parentheses.
3262  assert(Paren.Kind == DeclaratorChunk::Paren &&
3263  "do not have redundant top-level parentheses");
3264 
3265  // This is a syntactic check; we're not interested in cases that arise
3266  // during template instantiation.
3267  if (S.inTemplateInstantiation())
3268  return;
3269 
3270  // Check whether this could be intended to be a construction of a temporary
3271  // object in C++ via a function-style cast.
3272  bool CouldBeTemporaryObject =
3273  S.getLangOpts().CPlusPlus && D.isExpressionContext() &&
3274  !D.isInvalidType() && D.getIdentifier() &&
3276  (T->isRecordType() || T->isDependentType()) &&
3278 
3279  bool StartsWithDeclaratorId = true;
3280  for (auto &C : D.type_objects()) {
3281  switch (C.Kind) {
3283  if (&C == &Paren)
3284  continue;
3285  LLVM_FALLTHROUGH;
3287  StartsWithDeclaratorId = false;
3288  continue;
3289 
3291  if (!C.Arr.NumElts)
3292  CouldBeTemporaryObject = false;
3293  continue;
3294 
3296  // FIXME: Suppress the warning here if there is no initializer; we're
3297  // going to give an error anyway.
3298  // We assume that something like 'T (&x) = y;' is highly likely to not
3299  // be intended to be a temporary object.
3300  CouldBeTemporaryObject = false;
3301  StartsWithDeclaratorId = false;
3302  continue;
3303 
3305  // In a new-type-id, function chunks require parentheses.
3307  return;
3308  // FIXME: "A(f())" deserves a vexing-parse warning, not just a
3309  // redundant-parens warning, but we don't know whether the function
3310  // chunk was syntactically valid as an expression here.
3311  CouldBeTemporaryObject = false;
3312  continue;
3313 
3316  case DeclaratorChunk::Pipe:
3317  // These cannot appear in expressions.
3318  CouldBeTemporaryObject = false;
3319  StartsWithDeclaratorId = false;
3320  continue;
3321  }
3322  }
3323 
3324  // FIXME: If there is an initializer, assume that this is not intended to be
3325  // a construction of a temporary object.
3326 
3327  // Check whether the name has already been declared; if not, this is not a
3328  // function-style cast.
3329  if (CouldBeTemporaryObject) {
3332  if (!S.LookupName(Result, S.getCurScope()))
3333  CouldBeTemporaryObject = false;
3334  Result.suppressDiagnostics();
3335  }
3336 
3337  SourceRange ParenRange(Paren.Loc, Paren.EndLoc);
3338 
3339  if (!CouldBeTemporaryObject) {
3340  // If we have A (::B), the parentheses affect the meaning of the program.
3341  // Suppress the warning in that case. Don't bother looking at the DeclSpec
3342  // here: even (e.g.) "int ::x" is visually ambiguous even though it's
3343  // formally unambiguous.
3344  if (StartsWithDeclaratorId && D.getCXXScopeSpec().isValid()) {
3345  for (NestedNameSpecifier *NNS = D.getCXXScopeSpec().getScopeRep(); NNS;
3346  NNS = NNS->getPrefix()) {
3347  if (NNS->getKind() == NestedNameSpecifier::Global)
3348  return;
3349  }
3350  }
3351 
3352  S.Diag(Paren.Loc, diag::warn_redundant_parens_around_declarator)
3353  << ParenRange << FixItHint::CreateRemoval(Paren.Loc)
3354  << FixItHint::CreateRemoval(Paren.EndLoc);
3355  return;
3356  }
3357 
3358  S.Diag(Paren.Loc, diag::warn_parens_disambiguated_as_variable_declaration)
3359  << ParenRange << D.getIdentifier();
3360  auto *RD = T->getAsCXXRecordDecl();
3361  if (!RD || !RD->hasDefinition() || RD->hasNonTrivialDestructor())
3362  S.Diag(Paren.Loc, diag::note_raii_guard_add_name)
3363  << FixItHint::CreateInsertion(Paren.Loc, " varname") << T
3364  << D.getIdentifier();
3365  // FIXME: A cast to void is probably a better suggestion in cases where it's
3366  // valid (when there is no initializer and we're not in a condition).
3367  S.Diag(D.getBeginLoc(), diag::note_function_style_cast_add_parentheses)
3370  S.Diag(Paren.Loc, diag::note_remove_parens_for_variable_declaration)
3371  << FixItHint::CreateRemoval(Paren.Loc)
3372  << FixItHint::CreateRemoval(Paren.EndLoc);
3373 }
3374 
3375 /// Helper for figuring out the default CC for a function declarator type. If
3376 /// this is the outermost chunk, then we can determine the CC from the
3377 /// declarator context. If not, then this could be either a member function
3378 /// type or normal function type.
3380  Sema &S, Declarator &D, const ParsedAttributesView &AttrList,
3381  const DeclaratorChunk::FunctionTypeInfo &FTI, unsigned ChunkIndex) {
3382  assert(D.getTypeObject(ChunkIndex).Kind == DeclaratorChunk::Function);
3383 
3384  // Check for an explicit CC attribute.
3385  for (const ParsedAttr &AL : AttrList) {
3386  switch (AL.getKind()) {
3388  // Ignore attributes that don't validate or can't apply to the
3389  // function type. We'll diagnose the failure to apply them in
3390  // handleFunctionTypeAttr.
3391  CallingConv CC;
3392  if (!S.CheckCallingConvAttr(AL, CC) &&
3393  (!FTI.isVariadic || supportsVariadicCall(CC))) {
3394  return CC;
3395  }
3396  break;
3397  }
3398 
3399  default:
3400  break;
3401  }
3402  }
3403 
3404  bool IsCXXInstanceMethod = false;
3405 
3406  if (S.getLangOpts().CPlusPlus) {
3407  // Look inwards through parentheses to see if this chunk will form a
3408  // member pointer type or if we're the declarator. Any type attributes
3409  // between here and there will override the CC we choose here.
3410  unsigned I = ChunkIndex;
3411  bool FoundNonParen = false;
3412  while (I && !FoundNonParen) {
3413  --I;
3415  FoundNonParen = true;
3416  }
3417 
3418  if (FoundNonParen) {
3419  // If we're not the declarator, we're a regular function type unless we're
3420  // in a member pointer.
3421  IsCXXInstanceMethod =
3424  // This can only be a call operator for a lambda, which is an instance
3425  // method.
3426  IsCXXInstanceMethod = true;
3427  } else {
3428  // We're the innermost decl chunk, so must be a function declarator.
3429  assert(D.isFunctionDeclarator());
3430 
3431  // If we're inside a record, we're declaring a method, but it could be
3432  // explicitly or implicitly static.
3433  IsCXXInstanceMethod =
3436  !D.isStaticMember();
3437  }
3438  }
3439 
3441  IsCXXInstanceMethod);
3442 
3443  // Attribute AT_OpenCLKernel affects the calling convention for SPIR
3444  // and AMDGPU targets, hence it cannot be treated as a calling
3445  // convention attribute. This is the simplest place to infer
3446  // calling convention for OpenCL kernels.
3447  if (S.getLangOpts().OpenCL) {
3448  for (const ParsedAttr &AL : D.getDeclSpec().getAttributes()) {
3449  if (AL.getKind() == ParsedAttr::AT_OpenCLKernel) {
3450  CC = CC_OpenCLKernel;
3451  break;
3452  }
3453  }
3454  }
3455 
3456  return CC;
3457 }
3458 
3459 namespace {
3460  /// A simple notion of pointer kinds, which matches up with the various
3461  /// pointer declarators.
3462  enum class SimplePointerKind {
3463  Pointer,
3464  BlockPointer,
3465  MemberPointer,
3466  Array,
3467  };
3468 } // end anonymous namespace
3469 
3471  switch (nullability) {
3473  if (!Ident__Nonnull)
3474  Ident__Nonnull = PP.getIdentifierInfo("_Nonnull");
3475  return Ident__Nonnull;
3476 
3478  if (!Ident__Nullable)
3479  Ident__Nullable = PP.getIdentifierInfo("_Nullable");
3480  return Ident__Nullable;
3481 
3483  if (!Ident__Null_unspecified)
3484  Ident__Null_unspecified = PP.getIdentifierInfo("_Null_unspecified");
3485  return Ident__Null_unspecified;
3486  }
3487  llvm_unreachable("Unknown nullability kind.");
3488 }
3489 
3490 /// Retrieve the identifier "NSError".
3492  if (!Ident_NSError)
3493  Ident_NSError = PP.getIdentifierInfo("NSError");
3494 
3495  return Ident_NSError;
3496 }
3497 
3498 /// Check whether there is a nullability attribute of any kind in the given
3499 /// attribute list.
3500 static bool hasNullabilityAttr(const ParsedAttributesView &attrs) {
3501  for (const ParsedAttr &AL : attrs) {
3502  if (AL.getKind() == ParsedAttr::AT_TypeNonNull ||
3503  AL.getKind() == ParsedAttr::AT_TypeNullable ||
3504  AL.getKind() == ParsedAttr::AT_TypeNullUnspecified)
3505  return true;
3506  }
3507 
3508  return false;
3509 }
3510 
3511 namespace {
3512  /// Describes the kind of a pointer a declarator describes.
3514  // Not a pointer.
3515  NonPointer,
3516  // Single-level pointer.
3517  SingleLevelPointer,
3518  // Multi-level pointer (of any pointer kind).
3519  MultiLevelPointer,
3520  // CFFooRef*
3521  MaybePointerToCFRef,
3522  // CFErrorRef*
3523  CFErrorRefPointer,
3524  // NSError**
3525  NSErrorPointerPointer,
3526  };
3527 
3528  /// Describes a declarator chunk wrapping a pointer that marks inference as
3529  /// unexpected.
3530  // These values must be kept in sync with diagnostics.
3532  /// Pointer is top-level.
3533  None = -1,
3534  /// Pointer is an array element.
3535  Array = 0,
3536  /// Pointer is the referent type of a C++ reference.
3537  Reference = 1
3538  };
3539 } // end anonymous namespace
3540 
3541 /// Classify the given declarator, whose type-specified is \c type, based on
3542 /// what kind of pointer it refers to.
3543 ///
3544 /// This is used to determine the default nullability.
3545 static PointerDeclaratorKind
3547  PointerWrappingDeclaratorKind &wrappingKind) {
3548  unsigned numNormalPointers = 0;
3549 
3550  // For any dependent type, we consider it a non-pointer.
3551  if (type->isDependentType())
3552  return PointerDeclaratorKind::NonPointer;
3553 
3554  // Look through the declarator chunks to identify pointers.
3555  for (unsigned i = 0, n = declarator.getNumTypeObjects(); i != n; ++i) {
3556  DeclaratorChunk &chunk = declarator.getTypeObject(i);
3557  switch (chunk.Kind) {
3559  if (numNormalPointers == 0)
3560  wrappingKind = PointerWrappingDeclaratorKind::Array;
3561  break;
3562 
3564  case DeclaratorChunk::Pipe:
3565  break;
3566 
3569  return numNormalPointers > 0 ? PointerDeclaratorKind::MultiLevelPointer
3570  : PointerDeclaratorKind::SingleLevelPointer;
3571 
3573  break;
3574 
3576  if (numNormalPointers == 0)
3577  wrappingKind = PointerWrappingDeclaratorKind::Reference;
3578  break;
3579 
3581  ++numNormalPointers;
3582  if (numNormalPointers > 2)
3583  return PointerDeclaratorKind::MultiLevelPointer;
3584  break;
3585  }
3586  }
3587 
3588  // Then, dig into the type specifier itself.
3589  unsigned numTypeSpecifierPointers = 0;
3590  do {
3591  // Decompose normal pointers.
3592  if (auto ptrType = type->getAs<PointerType>()) {
3593  ++numNormalPointers;
3594 
3595  if (numNormalPointers > 2)
3596  return PointerDeclaratorKind::MultiLevelPointer;
3597 
3598  type = ptrType->getPointeeType();
3599  ++numTypeSpecifierPointers;
3600  continue;
3601  }
3602 
3603  // Decompose block pointers.
3604  if (type->getAs<BlockPointerType>()) {
3605  return numNormalPointers > 0 ? PointerDeclaratorKind::MultiLevelPointer
3606  : PointerDeclaratorKind::SingleLevelPointer;
3607  }
3608 
3609  // Decompose member pointers.
3610  if (type->getAs<MemberPointerType>()) {
3611  return numNormalPointers > 0 ? PointerDeclaratorKind::MultiLevelPointer
3612  : PointerDeclaratorKind::SingleLevelPointer;
3613  }
3614 
3615  // Look at Objective-C object pointers.
3616  if (auto objcObjectPtr = type->getAs<ObjCObjectPointerType>()) {
3617  ++numNormalPointers;
3618  ++numTypeSpecifierPointers;
3619 
3620  // If this is NSError**, report that.
3621  if (auto objcClassDecl = objcObjectPtr->getInterfaceDecl()) {
3622  if (objcClassDecl->getIdentifier() == S.getNSErrorIdent() &&
3623  numNormalPointers == 2 && numTypeSpecifierPointers < 2) {
3624  return PointerDeclaratorKind::NSErrorPointerPointer;
3625  }
3626  }
3627 
3628  break;
3629  }
3630 
3631  // Look at Objective-C class types.
3632  if (auto objcClass = type->getAs<ObjCInterfaceType>()) {
3633  if (objcClass->getInterface()->getIdentifier() == S.getNSErrorIdent()) {
3634  if (numNormalPointers == 2 && numTypeSpecifierPointers < 2)
3635  return PointerDeclaratorKind::NSErrorPointerPointer;
3636  }
3637 
3638  break;
3639  }
3640 
3641  // If at this point we haven't seen a pointer, we won't see one.
3642  if (numNormalPointers == 0)
3643  return PointerDeclaratorKind::NonPointer;
3644 
3645  if (auto recordType = type->getAs<RecordType>()) {
3646  RecordDecl *recordDecl = recordType->getDecl();
3647 
3648  bool isCFError = false;
3649  if (S.CFError) {
3650  // If we already know about CFError, test it directly.
3651  isCFError = (S.CFError == recordDecl);
3652  } else {
3653  // Check whether this is CFError, which we identify based on its bridge
3654  // to NSError. CFErrorRef used to be declared with "objc_bridge" but is
3655  // now declared with "objc_bridge_mutable", so look for either one of
3656  // the two attributes.
3657  if (recordDecl->getTagKind() == TTK_Struct && numNormalPointers > 0) {
3658  IdentifierInfo *bridgedType = nullptr;
3659  if (auto bridgeAttr = recordDecl->getAttr<ObjCBridgeAttr>())
3660  bridgedType = bridgeAttr->getBridgedType();
3661  else if (auto bridgeAttr =
3662  recordDecl->getAttr<ObjCBridgeMutableAttr>())
3663  bridgedType = bridgeAttr->getBridgedType();
3664 
3665  if (bridgedType == S.getNSErrorIdent()) {
3666  S.CFError = recordDecl;
3667  isCFError = true;
3668  }
3669  }
3670  }
3671 
3672  // If this is CFErrorRef*, report it as such.
3673  if (isCFError && numNormalPointers == 2 && numTypeSpecifierPointers < 2) {
3674  return PointerDeclaratorKind::CFErrorRefPointer;
3675  }
3676  break;
3677  }
3678 
3679  break;
3680  } while (true);
3681 
3682  switch (numNormalPointers) {
3683  case 0:
3684  return PointerDeclaratorKind::NonPointer;
3685 
3686  case 1:
3687  return PointerDeclaratorKind::SingleLevelPointer;
3688 
3689  case 2:
3690  return PointerDeclaratorKind::MaybePointerToCFRef;
3691 
3692  default:
3693  return PointerDeclaratorKind::MultiLevelPointer;
3694  }
3695 }
3696 
3698  SourceLocation loc) {
3699  // If we're anywhere in a function, method, or closure context, don't perform
3700  // completeness checks.
3701  for (DeclContext *ctx = S.CurContext; ctx; ctx = ctx->getParent()) {
3702  if (ctx->isFunctionOrMethod())
3703  return FileID();
3704 
3705  if (ctx->isFileContext())
3706  break;
3707  }
3708 
3709  // We only care about the expansion location.
3710  loc = S.SourceMgr.getExpansionLoc(loc);
3711  FileID file = S.SourceMgr.getFileID(loc);
3712  if (file.isInvalid())
3713  return FileID();
3714 
3715  // Retrieve file information.
3716  bool invalid = false;
3717  const SrcMgr::SLocEntry &sloc = S.SourceMgr.getSLocEntry(file, &invalid);
3718  if (invalid || !sloc.isFile())
3719  return FileID();
3720 
3721  // We don't want to perform completeness checks on the main file or in
3722  // system headers.
3723  const SrcMgr::FileInfo &fileInfo = sloc.getFile();
3724  if (fileInfo.getIncludeLoc().isInvalid())
3725  return FileID();
3726  if (fileInfo.getFileCharacteristic() != SrcMgr::C_User &&
3728  return FileID();
3729  }
3730 
3731  return file;
3732 }
3733 
3734 /// Creates a fix-it to insert a C-style nullability keyword at \p pointerLoc,
3735 /// taking into account whitespace before and after.
3737  SourceLocation PointerLoc,
3739  assert(PointerLoc.isValid());
3740  if (PointerLoc.isMacroID())
3741  return;
3742 
3743  SourceLocation FixItLoc = S.getLocForEndOfToken(PointerLoc);
3744  if (!FixItLoc.isValid() || FixItLoc == PointerLoc)
3745  return;
3746 
3747  const char *NextChar = S.SourceMgr.getCharacterData(FixItLoc);
3748  if (!NextChar)
3749  return;
3750 
3751  SmallString<32> InsertionTextBuf{" "};
3752  InsertionTextBuf += getNullabilitySpelling(Nullability);
3753  InsertionTextBuf += " ";
3754  StringRef InsertionText = InsertionTextBuf.str();
3755 
3756  if (isWhitespace(*NextChar)) {
3757  InsertionText = InsertionText.drop_back();
3758  } else if (NextChar[-1] == '[') {
3759  if (NextChar[0] == ']')
3760  InsertionText = InsertionText.drop_back().drop_front();
3761  else
3762  InsertionText = InsertionText.drop_front();
3763  } else if (!isIdentifierBody(NextChar[0], /*allow dollar*/true) &&
3764  !isIdentifierBody(NextChar[-1], /*allow dollar*/true)) {
3765  InsertionText = InsertionText.drop_back().drop_front();
3766  }
3767 
3768  Diag << FixItHint::CreateInsertion(FixItLoc, InsertionText);
3769 }
3770 
3772  SimplePointerKind PointerKind,
3773  SourceLocation PointerLoc,
3774  SourceLocation PointerEndLoc) {
3775  assert(PointerLoc.isValid());
3776 
3777  if (PointerKind == SimplePointerKind::Array) {
3778  S.Diag(PointerLoc, diag::warn_nullability_missing_array);
3779  } else {
3780  S.Diag(PointerLoc, diag::warn_nullability_missing)
3781  << static_cast<unsigned>(PointerKind);
3782  }
3783 
3784  auto FixItLoc = PointerEndLoc.isValid() ? PointerEndLoc : PointerLoc;
3785  if (FixItLoc.isMacroID())
3786  return;
3787 
3788  auto addFixIt = [&](NullabilityKind Nullability) {
3789  auto Diag = S.Diag(FixItLoc, diag::note_nullability_fix_it);
3790  Diag << static_cast<unsigned>(Nullability);
3791  Diag << static_cast<unsigned>(PointerKind);
3792  fixItNullability(S, Diag, FixItLoc, Nullability);
3793  };
3794  addFixIt(NullabilityKind::Nullable);
3795  addFixIt(NullabilityKind::NonNull);
3796 }
3797 
3798 /// Complains about missing nullability if the file containing \p pointerLoc
3799 /// has other uses of nullability (either the keywords or the \c assume_nonnull
3800 /// pragma).
3801 ///
3802 /// If the file has \e not seen other uses of nullability, this particular
3803 /// pointer is saved for possible later diagnosis. See recordNullabilitySeen().
3804 static void
3806  SourceLocation pointerLoc,
3807  SourceLocation pointerEndLoc = SourceLocation()) {
3808  // Determine which file we're performing consistency checking for.
3809  FileID file = getNullabilityCompletenessCheckFileID(S, pointerLoc);
3810  if (file.isInvalid())
3811  return;
3812 
3813  // If we haven't seen any type nullability in this file, we won't warn now
3814  // about anything.
3815  FileNullability &fileNullability = S.NullabilityMap[file];
3816  if (!fileNullability.SawTypeNullability) {
3817  // If this is the first pointer declarator in the file, and the appropriate
3818  // warning is on, record it in case we need to diagnose it retroactively.
3819  diag::kind diagKind;
3820  if (pointerKind == SimplePointerKind::Array)
3821  diagKind = diag::warn_nullability_missing_array;
3822  else
3823  diagKind = diag::warn_nullability_missing;
3824 
3825  if (fileNullability.PointerLoc.isInvalid() &&
3826  !S.Context.getDiagnostics().isIgnored(diagKind, pointerLoc)) {
3827  fileNullability.PointerLoc = pointerLoc;
3828  fileNullability.PointerEndLoc = pointerEndLoc;
3829  fileNullability.PointerKind = static_cast<unsigned>(pointerKind);
3830  }
3831 
3832  return;
3833  }
3834 
3835  // Complain about missing nullability.
3836  emitNullabilityConsistencyWarning(S, pointerKind, pointerLoc, pointerEndLoc);
3837 }
3838 
3839 /// Marks that a nullability feature has been used in the file containing
3840 /// \p loc.
3841 ///
3842 /// If this file already had pointer types in it that were missing nullability,
3843 /// the first such instance is retroactively diagnosed.
3844 ///
3845 /// \sa checkNullabilityConsistency
3848  if (file.isInvalid())
3849  return;
3850 
3851  FileNullability &fileNullability = S.NullabilityMap[file];
3852  if (fileNullability.SawTypeNullability)
3853  return;
3854  fileNullability.SawTypeNullability = true;
3855 
3856  // If we haven't seen any type nullability before, now we have. Retroactively
3857  // diagnose the first unannotated pointer, if there was one.
3858  if (fileNullability.PointerLoc.isInvalid())
3859  return;
3860 
3861  auto kind = static_cast<SimplePointerKind>(fileNullability.PointerKind);
3863  fileNullability.PointerEndLoc);
3864 }
3865 
3866 /// Returns true if any of the declarator chunks before \p endIndex include a
3867 /// level of indirection: array, pointer, reference, or pointer-to-member.
3868 ///
3869 /// Because declarator chunks are stored in outer-to-inner order, testing
3870 /// every chunk before \p endIndex is testing all chunks that embed the current
3871 /// chunk as part of their type.
3872 ///
3873 /// It is legal to pass the result of Declarator::getNumTypeObjects() as the
3874 /// end index, in which case all chunks are tested.
3875 static bool hasOuterPointerLikeChunk(const Declarator &D, unsigned endIndex) {
3876  unsigned i = endIndex;
3877  while (i != 0) {
3878  // Walk outwards along the declarator chunks.
3879  --i;
3880  const DeclaratorChunk &DC = D.getTypeObject(i);
3881  switch (DC.Kind) {
3883  break;
3888  return true;
3891  case DeclaratorChunk::Pipe:
3892  // These are invalid anyway, so just ignore.
3893  break;
3894  }
3895  }
3896  return false;
3897 }
3898 
3900  return (Chunk.Kind == DeclaratorChunk::Pointer ||
3901  Chunk.Kind == DeclaratorChunk::Array);
3902 }
3903 
3904 template<typename AttrT>
3906  Attr.setUsedAsTypeAttr();
3907  return ::new (Ctx)
3908  AttrT(Attr.getRange(), Ctx, Attr.getAttributeSpellingListIndex());
3909 }
3910 
3912  NullabilityKind NK) {
3913  switch (NK) {
3915  return createSimpleAttr<TypeNonNullAttr>(Ctx, Attr);
3916 
3918  return createSimpleAttr<TypeNullableAttr>(Ctx, Attr);
3919 
3921  return createSimpleAttr<TypeNullUnspecifiedAttr>(Ctx, Attr);
3922  }
3923  llvm_unreachable("unknown NullabilityKind");
3924 }
3925 
3926 // Diagnose whether this is a case with the multiple addr spaces.
3927 // Returns true if this is an invalid case.
3928 // ISO/IEC TR 18037 S5.3 (amending C99 6.7.3): "No type shall be qualified
3929 // by qualifiers for two or more different address spaces."
3931  LangAS ASNew,
3932  SourceLocation AttrLoc) {
3933  if (ASOld != LangAS::Default) {
3934  if (ASOld != ASNew) {
3935  S.Diag(AttrLoc, diag::err_attribute_address_multiple_qualifiers);
3936  return true;
3937  }
3938  // Emit a warning if they are identical; it's likely unintended.
3939  S.Diag(AttrLoc,
3940  diag::warn_attribute_address_multiple_identical_qualifiers);
3941  }
3942  return false;
3943 }
3944 
3945 static TypeSourceInfo *
3946 GetTypeSourceInfoForDeclarator(TypeProcessingState &State,
3947  QualType T, TypeSourceInfo *ReturnTypeInfo);
3948 
3949 static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
3950  QualType declSpecType,
3951  TypeSourceInfo *TInfo) {
3952  // The TypeSourceInfo that this function returns will not be a null type.
3953  // If there is an error, this function will fill in a dummy type as fallback.
3954  QualType T = declSpecType;
3955  Declarator &D = state.getDeclarator();
3956  Sema &S = state.getSema();
3957  ASTContext &Context = S.Context;
3958  const LangOptions &LangOpts = S.getLangOpts();
3959 
3960  // The name we're declaring, if any.
3961  DeclarationName Name;
3962  if (D.getIdentifier())
3963  Name = D.getIdentifier();
3964 
3965  // Does this declaration declare a typedef-name?
3966  bool IsTypedefName =
3970 
3971  // Does T refer to a function type with a cv-qualifier or a ref-qualifier?
3972  bool IsQualifiedFunction = T->isFunctionProtoType() &&
3973  (!T->castAs<FunctionProtoType>()->getMethodQuals().empty() ||
3974  T->castAs<FunctionProtoType>()->getRefQualifier() != RQ_None);
3975 
3976  // If T is 'decltype(auto)', the only declarators we can have are parens
3977  // and at most one function declarator if this is a function declaration.
3978  // If T is a deduced class template specialization type, we can have no
3979  // declarator chunks at all.
3980  if (auto *DT = T->getAs<DeducedType>()) {
3981  const AutoType *AT = T->getAs<AutoType>();
3982  bool IsClassTemplateDeduction = isa<DeducedTemplateSpecializationType>(DT);
3983  if ((AT && AT->isDecltypeAuto()) || IsClassTemplateDeduction) {
3984  for (unsigned I = 0, E = D.getNumTypeObjects(); I != E; ++I) {
3985  unsigned Index = E - I - 1;
3986  DeclaratorChunk &DeclChunk = D.getTypeObject(Index);
3987  unsigned DiagId = IsClassTemplateDeduction
3988  ? diag::err_deduced_class_template_compound_type
3989  : diag::err_decltype_auto_compound_type;
3990  unsigned DiagKind = 0;
3991  switch (DeclChunk.Kind) {
3993  // FIXME: Rejecting this is a little silly.
3994  if (IsClassTemplateDeduction) {
3995  DiagKind = 4;
3996  break;
3997  }
3998  continue;
4000  if (IsClassTemplateDeduction) {
4001  DiagKind = 3;
4002  break;
4003  }
4004  unsigned FnIndex;
4005  if (D.isFunctionDeclarationContext() &&
4006  D.isFunctionDeclarator(FnIndex) && FnIndex == Index)
4007  continue;
4008  DiagId = diag::err_decltype_auto_function_declarator_not_declaration;
4009  break;
4010  }
4014  DiagKind = 0;
4015  break;
4017  DiagKind = 1;
4018  break;
4020  DiagKind = 2;
4021  break;
4022  case DeclaratorChunk::Pipe:
4023  break;
4024  }
4025 
4026  S.Diag(DeclChunk.Loc, DiagId) << DiagKind;
4027  D.setInvalidType(true);
4028  break;
4029  }
4030  }
4031  }
4032 
4033  // Determine whether we should infer _Nonnull on pointer types.
4034  Optional<NullabilityKind> inferNullability;
4035  bool inferNullabilityCS = false;
4036  bool inferNullabilityInnerOnly = false;
4037  bool inferNullabilityInnerOnlyComplete = false;
4038 
4039  // Are we in an assume-nonnull region?
4040  bool inAssumeNonNullRegion = false;
4041  SourceLocation assumeNonNullLoc = S.PP.getPragmaAssumeNonNullLoc();
4042  if (assumeNonNullLoc.isValid()) {
4043  inAssumeNonNullRegion = true;
4044  recordNullabilitySeen(S, assumeNonNullLoc);
4045  }
4046 
4047  // Whether to complain about missing nullability specifiers or not.
4048  enum {
4049  /// Never complain.
4050  CAMN_No,
4051  /// Complain on the inner pointers (but not the outermost
4052  /// pointer).
4053  CAMN_InnerPointers,
4054  /// Complain about any pointers that don't have nullability
4055  /// specified or inferred.
4056  CAMN_Yes
4057  } complainAboutMissingNullability = CAMN_No;
4058  unsigned NumPointersRemaining = 0;
4059  auto complainAboutInferringWithinChunk = PointerWrappingDeclaratorKind::None;
4060 
4061  if (IsTypedefName) {
4062  // For typedefs, we do not infer any nullability (the default),
4063  // and we only complain about missing nullability specifiers on
4064  // inner pointers.
4065  complainAboutMissingNullability = CAMN_InnerPointers;
4066 
4067  if (T->canHaveNullability(/*ResultIfUnknown*/false) &&
4068  !T->getNullability(S.Context)) {
4069  // Note that we allow but don't require nullability on dependent types.
4070  ++NumPointersRemaining;
4071  }
4072 
4073  for (unsigned i = 0, n = D.getNumTypeObjects(); i != n; ++i) {
4074  DeclaratorChunk &chunk = D.getTypeObject(i);
4075  switch (chunk.Kind) {
4078  case DeclaratorChunk::Pipe:
4079  break;
4080 
4083  ++NumPointersRemaining;
4084  break;
4085 
4088  continue;
4089 
4091  ++NumPointersRemaining;
4092  continue;
4093  }
4094  }
4095  } else {
4096  bool isFunctionOrMethod = false;
4097  switch (auto context = state.getDeclarator().getContext()) {
4103  isFunctionOrMethod = true;
4104  LLVM_FALLTHROUGH;
4105 
4107  if (state.getDeclarator().isObjCIvar() && !isFunctionOrMethod) {
4108  complainAboutMissingNullability = CAMN_No;
4109  break;
4110  }
4111 
4112  // Weak properties are inferred to be nullable.
4113  if (state.getDeclarator().isObjCWeakProperty() && inAssumeNonNullRegion) {
4114  inferNullability = NullabilityKind::Nullable;
4115  break;
4116  }
4117 
4118  LLVM_FALLTHROUGH;
4119 
4122  complainAboutMissingNullability = CAMN_Yes;
4123 
4124  // Nullability inference depends on the type and declarator.
4125  auto wrappingKind = PointerWrappingDeclaratorKind::None;
4126  switch (classifyPointerDeclarator(S, T, D, wrappingKind)) {
4127  case PointerDeclaratorKind::NonPointer:
4128  case PointerDeclaratorKind::MultiLevelPointer:
4129  // Cannot infer nullability.
4130  break;
4131 
4132  case PointerDeclaratorKind::SingleLevelPointer:
4133  // Infer _Nonnull if we are in an assumes-nonnull region.
4134  if (inAssumeNonNullRegion) {
4135  complainAboutInferringWithinChunk = wrappingKind;
4136  inferNullability = NullabilityKind::NonNull;
4137  inferNullabilityCS =
4140  }
4141  break;
4142 
4143  case PointerDeclaratorKind::CFErrorRefPointer:
4144  case PointerDeclaratorKind::NSErrorPointerPointer:
4145  // Within a function or method signature, infer _Nullable at both
4146  // levels.
4147  if (isFunctionOrMethod && inAssumeNonNullRegion)
4148  inferNullability = NullabilityKind::Nullable;
4149  break;
4150 
4151  case PointerDeclaratorKind::MaybePointerToCFRef:
4152  if (isFunctionOrMethod) {
4153  // On pointer-to-pointer parameters marked cf_returns_retained or
4154  // cf_returns_not_retained, if the outer pointer is explicit then
4155  // infer the inner pointer as _Nullable.
4156  auto hasCFReturnsAttr =
4157  [](const ParsedAttributesView &AttrList) -> bool {
4158  return AttrList.hasAttribute(ParsedAttr::AT_CFReturnsRetained) ||
4159  AttrList.hasAttribute(ParsedAttr::AT_CFReturnsNotRetained);
4160  };
4161  if (const auto *InnermostChunk = D.getInnermostNonParenChunk()) {
4162  if (hasCFReturnsAttr(D.getAttributes()) ||
4163  hasCFReturnsAttr(InnermostChunk->getAttrs()) ||
4164  hasCFReturnsAttr(D.getDeclSpec().getAttributes())) {
4165  inferNullability = NullabilityKind::Nullable;
4166  inferNullabilityInnerOnly = true;
4167  }
4168  }
4169  }
4170  break;
4171  }
4172  break;
4173  }
4174 
4176  complainAboutMissingNullability = CAMN_Yes;
4177  break;
4178 
4196  // Don't infer in these contexts.
4197  break;
4198  }
4199  }
4200 
4201  // Local function that returns true if its argument looks like a va_list.
4202  auto isVaList = [&S](QualType T) -> bool {
4203  auto *typedefTy = T->getAs<TypedefType>();
4204  if (!typedefTy)
4205  return false;
4206  TypedefDecl *vaListTypedef = S.Context.getBuiltinVaListDecl();
4207  do {
4208  if (typedefTy->getDecl() == vaListTypedef)
4209  return true;
4210  if (auto *name = typedefTy->getDecl()->getIdentifier())
4211  if (name->isStr("va_list"))
4212  return true;
4213  typedefTy = typedefTy->desugar()->getAs<TypedefType>();
4214  } while (typedefTy);
4215  return false;
4216  };
4217 
4218  // Local function that checks the nullability for a given pointer declarator.
4219  // Returns true if _Nonnull was inferred.
4220  auto inferPointerNullability =
4221  [&](SimplePointerKind pointerKind, SourceLocation pointerLoc,
4222  SourceLocation pointerEndLoc,
4223  ParsedAttributesView &attrs) -> ParsedAttr * {
4224  // We've seen a pointer.
4225  if (NumPointersRemaining > 0)
4226  --NumPointersRemaining;
4227 
4228  // If a nullability attribute is present, there's nothing to do.
4229  if (hasNullabilityAttr(attrs))
4230  return nullptr;
4231 
4232  // If we're supposed to infer nullability, do so now.
4233  if (inferNullability && !inferNullabilityInnerOnlyComplete) {
4234  ParsedAttr::Syntax syntax = inferNullabilityCS
4237  ParsedAttr *nullabilityAttr =
4238  state.getDeclarator().getAttributePool().create(
4239  S.getNullabilityKeyword(*inferNullability),
4240  SourceRange(pointerLoc), nullptr, SourceLocation(), nullptr, 0,
4241  syntax);
4242 
4243  attrs.addAtEnd(nullabilityAttr);
4244 
4245  if (inferNullabilityCS) {
4246  state.getDeclarator().getMutableDeclSpec().getObjCQualifiers()
4247  ->setObjCDeclQualifier(ObjCDeclSpec::DQ_CSNullability);
4248  }
4249 
4250  if (pointerLoc.isValid() &&
4251  complainAboutInferringWithinChunk !=
4253  auto Diag =
4254  S.Diag(pointerLoc, diag::warn_nullability_inferred_on_nested_type);
4255  Diag << static_cast<int>(complainAboutInferringWithinChunk);
4257  }
4258 
4259  if (inferNullabilityInnerOnly)
4260  inferNullabilityInnerOnlyComplete = true;
4261  return nullabilityAttr;
4262  }
4263 
4264  // If we're supposed to complain about missing nullability, do so
4265  // now if it's truly missing.
4266  switch (complainAboutMissingNullability) {
4267  case CAMN_No:
4268  break;
4269 
4270  case CAMN_InnerPointers:
4271  if (NumPointersRemaining == 0)
4272  break;
4273  LLVM_FALLTHROUGH;
4274 
4275  case CAMN_Yes:
4276  checkNullabilityConsistency(S, pointerKind, pointerLoc, pointerEndLoc);
4277  }
4278  return nullptr;
4279  };
4280 
4281  // If the type itself could have nullability but does not, infer pointer
4282  // nullability and perform consistency checking.
4283  if (S.CodeSynthesisContexts.empty()) {
4284  if (T->canHaveNullability(/*ResultIfUnknown*/false) &&
4285  !T->getNullability(S.Context)) {
4286  if (isVaList(T)) {
4287  // Record that we've seen a pointer, but do nothing else.
4288  if (NumPointersRemaining > 0)
4289  --NumPointersRemaining;
4290  } else {
4291  SimplePointerKind pointerKind = SimplePointerKind::Pointer;
4292  if (T->isBlockPointerType())
4293  pointerKind = SimplePointerKind::BlockPointer;
4294  else if (T->isMemberPointerType())
4295  pointerKind = SimplePointerKind::MemberPointer;
4296 
4297  if (auto *attr = inferPointerNullability(
4298  pointerKind, D.getDeclSpec().getTypeSpecTypeLoc(),
4299  D.getDeclSpec().getEndLoc(),
4301  T = state.getAttributedType(
4302  createNullabilityAttr(Context, *attr, *inferNullability), T, T);
4303  }
4304  }
4305  }
4306 
4307  if (complainAboutMissingNullability == CAMN_Yes &&
4308  T->isArrayType() && !T->getNullability(S.Context) && !isVaList(T) &&
4309  D.isPrototypeContext() &&
4311  checkNullabilityConsistency(S, SimplePointerKind::Array,
4313  }
4314  }
4315 
4316  bool ExpectNoDerefChunk =
4317  state.getCurrentAttributes().hasAttribute(ParsedAttr::AT_NoDeref);
4318 
4319  // Walk the DeclTypeInfo, building the recursive type as we go.
4320  // DeclTypeInfos are ordered from the identifier out, which is
4321  // opposite of what we want :).
4322  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
4323  unsigned chunkIndex = e - i - 1;
4324  state.setCurrentChunkIndex(chunkIndex);
4325  DeclaratorChunk &DeclType = D.getTypeObject(chunkIndex);
4326  IsQualifiedFunction &= DeclType.Kind == DeclaratorChunk::Paren;
4327  switch (DeclType.Kind) {
4329  if (i == 0)
4330  warnAboutRedundantParens(S, D, T);
4331  T = S.BuildParenType(T);
4332  break;
4334  // If blocks are disabled, emit an error.
4335  if (!LangOpts.Blocks)
4336  S.Diag(DeclType.Loc, diag::err_blocks_disable) << LangOpts.OpenCL;
4337 
4338  // Handle pointer nullability.
4339  inferPointerNullability(SimplePointerKind::BlockPointer, DeclType.Loc,
4340  DeclType.EndLoc, DeclType.getAttrs());
4341 
4342  T = S.BuildBlockPointerType(T, D.getIdentifierLoc(), Name);
4343  if (DeclType.Cls.TypeQuals || LangOpts.OpenCL) {
4344  // OpenCL v2.0, s6.12.5 - Block variable declarations are implicitly
4345  // qualified with const.
4346  if (LangOpts.OpenCL)
4347  DeclType.Cls.TypeQuals |= DeclSpec::TQ_const;
4348  T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Cls.TypeQuals);
4349  }
4350  break;
4352  // Verify that we're not building a pointer to pointer to function with
4353  // exception specification.
4354  if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
4355  S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
4356  D.setInvalidType(true);
4357  // Build the type anyway.
4358  }
4359 
4360  // Handle pointer nullability
4361  inferPointerNullability(SimplePointerKind::Pointer, DeclType.Loc,
4362  DeclType.EndLoc, DeclType.getAttrs());
4363 
4364  if (LangOpts.ObjC && T->getAs<ObjCObjectType>()) {
4365  T = Context.getObjCObjectPointerType(T);
4366  if (DeclType.Ptr.TypeQuals)
4367  T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Ptr.TypeQuals);
4368  break;
4369  }
4370 
4371  // OpenCL v2.0 s6.9b - Pointer to image/sampler cannot be used.
4372  // OpenCL v2.0 s6.13.16.1 - Pointer to pipe cannot be used.
4373  // OpenCL v2.0 s6.12.5 - Pointers to Blocks are not allowed.
4374  if (LangOpts.OpenCL) {
4375  if (T->isImageType() || T->isSamplerT() || T->isPipeType() ||
4376  T->isBlockPointerType()) {
4377  S.Diag(D.getIdentifierLoc(), diag::err_opencl_pointer_to_type) << T;
4378  D.setInvalidType(true);
4379  }
4380  }
4381 
4382  T = S.BuildPointerType(T, DeclType.Loc, Name);
4383  if (DeclType.Ptr.TypeQuals)
4384  T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Ptr.TypeQuals);
4385  break;
4387  // Verify that we're not building a reference to pointer to function with
4388  // exception specification.
4389  if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
4390  S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
4391  D.setInvalidType(true);
4392  // Build the type anyway.
4393  }
4394  T = S.BuildReferenceType(T, DeclType.Ref.LValueRef, DeclType.Loc, Name);
4395 
4396  if (DeclType.Ref.HasRestrict)
4397  T = S.BuildQualifiedType(T, DeclType.Loc, Qualifiers::Restrict);
4398  break;
4399  }
4400  case DeclaratorChunk::Array: {
4401  // Verify that we're not building an array of pointers to function with
4402  // exception specification.
4403  if (LangOpts.CPlusPlus && S.CheckDistantExceptionSpec(T)) {
4404  S.Diag(D.getIdentifierLoc(), diag::err_distant_exception_spec);
4405  D.setInvalidType(true);
4406  // Build the type anyway.
4407  }
4408  DeclaratorChunk::ArrayTypeInfo &ATI = DeclType.Arr;
4409  Expr *ArraySize = static_cast<Expr*>(ATI.NumElts);
4411  if (ATI.isStar)
4412  ASM = ArrayType::Star;
4413  else if (ATI.hasStatic)
4414  ASM = ArrayType::Static;
4415  else
4416  ASM = ArrayType::Normal;
4417  if (ASM == ArrayType::Star && !D.isPrototypeContext()) {
4418  // FIXME: This check isn't quite right: it allows star in prototypes
4419  // for function definitions, and disallows some edge cases detailed
4420  // in http://gcc.gnu.org/ml/gcc-patches/2009-02/msg00133.html
4421  S.Diag(DeclType.Loc, diag::err_array_star_outside_prototype);
4422  ASM = ArrayType::Normal;
4423  D.setInvalidType(true);
4424  }
4425 
4426  // C99 6.7.5.2p1: The optional type qualifiers and the keyword static
4427  // shall appear only in a declaration of a function parameter with an
4428  // array type, ...
4429  if (ASM == ArrayType::Static || ATI.TypeQuals) {
4430  if (!(D.isPrototypeContext() ||
4432  S.Diag(DeclType.Loc, diag::err_array_static_outside_prototype) <<
4433  (ASM == ArrayType::Static ? "'static'" : "type qualifier");
4434  // Remove the 'static' and the type qualifiers.
4435  if (ASM == ArrayType::Static)
4436  ASM = ArrayType::Normal;
4437  ATI.TypeQuals = 0;
4438  D.setInvalidType(true);
4439  }
4440 
4441  // C99 6.7.5.2p1: ... and then only in the outermost array type
4442  // derivation.
4443  if (hasOuterPointerLikeChunk(D, chunkIndex)) {
4444  S.Diag(DeclType.Loc, diag::err_array_static_not_outermost) <<
4445  (ASM == ArrayType::Static ? "'static'" : "type qualifier");
4446  if (ASM == ArrayType::Static)
4447  ASM = ArrayType::Normal;
4448  ATI.TypeQuals = 0;
4449  D.setInvalidType(true);
4450  }
4451  }
4452  const AutoType *AT = T->getContainedAutoType();
4453  // Allow arrays of auto if we are a generic lambda parameter.
4454  // i.e. [](auto (&array)[5]) { return array[0]; }; OK
4455  if (AT &&
4457  // We've already diagnosed this for decltype(auto).
4458  if (!AT->isDecltypeAuto())
4459  S.Diag(DeclType.Loc, diag::err_illegal_decl_array_of_auto)
4460  << getPrintableNameForEntity(Name) << T;
4461  T = QualType();
4462  break;
4463  }
4464 
4465  // Array parameters can be marked nullable as well, although it's not
4466  // necessary if they're marked 'static'.
4467  if (complainAboutMissingNullability == CAMN_Yes &&
4468  !hasNullabilityAttr(DeclType.getAttrs()) &&
4469  ASM != ArrayType::Static &&
4470  D.isPrototypeContext() &&
4471  !hasOuterPointerLikeChunk(D, chunkIndex)) {
4472  checkNullabilityConsistency(S, SimplePointerKind::Array, DeclType.Loc);
4473  }
4474 
4475  T = S.BuildArrayType(T, ASM, ArraySize, ATI.TypeQuals,
4476  SourceRange(DeclType.Loc, DeclType.EndLoc), Name);
4477  break;
4478  }
4480  // If the function declarator has a prototype (i.e. it is not () and
4481  // does not have a K&R-style identifier list), then the arguments are part
4482  // of the type, otherwise the argument list is ().
4483  const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
4484  IsQualifiedFunction =
4486 
4487  // Check for auto functions and trailing return type and adjust the
4488  // return type accordingly.
4489  if (!D.isInvalidType()) {
4490  // trailing-return-type is only required if we're declaring a function,
4491  // and not, for instance, a pointer to a function.
4492  if (D.getDeclSpec().hasAutoTypeSpec() &&
4493  !FTI.hasTrailingReturnType() && chunkIndex == 0) {
4494  if (!S.getLangOpts().CPlusPlus14) {
4497  ? diag::err_auto_missing_trailing_return
4498  : diag::err_deduced_return_type);
4499  T = Context.IntTy;
4500  D.setInvalidType(true);
4501  } else {
4503  diag::warn_cxx11_compat_deduced_return_type);
4504  }
4505  } else if (FTI.hasTrailingReturnType()) {
4506  // T must be exactly 'auto' at this point. See CWG issue 681.
4507  if (isa<ParenType>(T)) {
4508  S.Diag(D.getBeginLoc(), diag::err_trailing_return_in_parens)
4509  << T << D.getSourceRange();
4510  D.setInvalidType(true);
4511  } else if (D.getName().getKind() ==
4513  if (T != Context.DependentTy) {
4514  S.Diag(D.getDeclSpec().getBeginLoc(),
4515  diag::err_deduction_guide_with_complex_decl)
4516  << D.getSourceRange();
4517  D.setInvalidType(true);
4518  }
4520  (T.hasQualifiers() || !isa<AutoType>(T) ||
4521  cast<AutoType>(T)->getKeyword() !=
4524  diag::err_trailing_return_without_auto)
4525  << T << D.getDeclSpec().getSourceRange();
4526  D.setInvalidType(true);
4527  }
4528  T = S.GetTypeFromParser(FTI.getTrailingReturnType(), &TInfo);
4529  if (T.isNull()) {
4530  // An error occurred parsing the trailing return type.
4531  T = Context.IntTy;
4532  D.setInvalidType(true);
4533  }
4534  } else {
4535  // This function type is not the type of the entity being declared,
4536  // so checking the 'auto' is not the responsibility of this chunk.
4537  }
4538  }
4539 
4540  // C99 6.7.5.3p1: The return type may not be a function or array type.
4541  // For conversion functions, we'll diagnose this particular error later.
4542  if (!D.isInvalidType() && (T->isArrayType() || T->isFunctionType()) &&
4543  (D.getName().getKind() !=
4545  unsigned diagID = diag::err_func_returning_array_function;
4546  // Last processing chunk in block context means this function chunk
4547  // represents the block.
4548  if (chunkIndex == 0 &&
4550  diagID = diag::err_block_returning_array_function;
4551  S.Diag(DeclType.Loc, diagID) << T->isFunctionType() << T;
4552  T = Context.IntTy;
4553  D.setInvalidType(true);
4554  }
4555 
4556  // Do not allow returning half FP value.
4557  // FIXME: This really should be in BuildFunctionType.
4558  if (T->isHalfType()) {
4559  if (S.getLangOpts().OpenCL) {
4560  if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
4561  S.Diag(D.getIdentifierLoc(), diag::err_opencl_invalid_return)
4562  << T << 0 /*pointer hint*/;
4563  D.setInvalidType(true);
4564  }
4565  } else if (!S.getLangOpts().HalfArgsAndReturns) {
4566  S.Diag(D.getIdentifierLoc(),
4567  diag::err_parameters_retval_cannot_have_fp16_type) << 1;
4568  D.setInvalidType(true);
4569  }
4570  }
4571 
4572  if (LangOpts.OpenCL) {
4573  // OpenCL v2.0 s6.12.5 - A block cannot be the return value of a
4574  // function.
4575  if (T->isBlockPointerType() || T->isImageType() || T->isSamplerT() ||
4576  T->isPipeType()) {
4577  S.Diag(D.getIdentifierLoc(), diag::err_opencl_invalid_return)
4578  << T << 1 /*hint off*/;
4579  D.setInvalidType(true);
4580  }
4581  // OpenCL doesn't support variadic functions and blocks
4582  // (s6.9.e and s6.12.5 OpenCL v2.0) except for printf.
4583  // We also allow here any toolchain reserved identifiers.
4584  if (FTI.isVariadic &&
4585  !(D.getIdentifier() &&
4586  ((D.getIdentifier()->getName() == "printf" &&
4587  LangOpts.OpenCLVersion >= 120) ||
4588  D.getIdentifier()->getName().startswith("__")))) {
4589  S.Diag(D.getIdentifierLoc(), diag::err_opencl_variadic_function);
4590  D.setInvalidType(true);
4591  }
4592  }
4593 
4594  // Methods cannot return interface types. All ObjC objects are
4595  // passed by reference.
4596  if (T->isObjCObjectType()) {
4597  SourceLocation DiagLoc, FixitLoc;
4598  if (TInfo) {
4599  DiagLoc = TInfo->getTypeLoc().getBeginLoc();
4600  FixitLoc = S.getLocForEndOfToken(TInfo->getTypeLoc().getEndLoc());
4601  } else {
4602  DiagLoc = D.getDeclSpec().getTypeSpecTypeLoc();
4603  FixitLoc = S.getLocForEndOfToken(D.getDeclSpec().getEndLoc());
4604  }
4605  S.Diag(DiagLoc, diag::err_object_cannot_be_passed_returned_by_value)
4606  << 0 << T
4607  << FixItHint::CreateInsertion(FixitLoc, "*");
4608 
4609  T = Context.getObjCObjectPointerType(T);
4610  if (TInfo) {
4611  TypeLocBuilder TLB;
4612  TLB.pushFullCopy(TInfo->getTypeLoc());
4614  TLoc.setStarLoc(FixitLoc);
4615  TInfo = TLB.getTypeSourceInfo(Context, T);
4616  }
4617 
4618  D.setInvalidType(true);
4619  }
4620 
4621  // cv-qualifiers on return types are pointless except when the type is a
4622  // class type in C++.
4623  if ((T.getCVRQualifiers() || T->isAtomicType()) &&
4624  !(S.getLangOpts().CPlusPlus &&
4625  (T->isDependentType() || T->isRecordType()))) {
4626  if (T->isVoidType() && !S.getLangOpts().CPlusPlus &&
4628  // [6.9.1/3] qualified void return is invalid on a C
4629  // function definition. Apparently ok on declarations and
4630  // in C++ though (!)
4631  S.Diag(DeclType.Loc, diag::err_func_returning_qualified_void) << T;
4632  } else
4633  diagnoseRedundantReturnTypeQualifiers(S, T, D, chunkIndex);
4634  }
4635 
4636  // Objective-C ARC ownership qualifiers are ignored on the function
4637  // return type (by type canonicalization). Complain if this attribute
4638  // was written here.
4639  if (T.getQualifiers().hasObjCLifetime()) {
4640  SourceLocation AttrLoc;
4641  if (chunkIndex + 1 < D.getNumTypeObjects()) {
4642  DeclaratorChunk ReturnTypeChunk = D.getTypeObject(chunkIndex + 1);
4643  for (const ParsedAttr &AL : ReturnTypeChunk.getAttrs()) {
4644  if (AL.getKind() == ParsedAttr::AT_ObjCOwnership) {
4645  AttrLoc = AL.getLoc();
4646  break;
4647  }
4648  }
4649  }
4650  if (AttrLoc.isInvalid()) {
4651  for (const ParsedAttr &AL : D.getDeclSpec().getAttributes()) {
4652  if (AL.getKind() == ParsedAttr::AT_ObjCOwnership) {
4653  AttrLoc = AL.getLoc();
4654  break;
4655  }
4656  }
4657  }
4658 
4659  if (AttrLoc.isValid()) {
4660  // The ownership attributes are almost always written via
4661  // the predefined
4662  // __strong/__weak/__autoreleasing/__unsafe_unretained.
4663  if (AttrLoc.isMacroID())
4664  AttrLoc =
4666 
4667  S.Diag(AttrLoc, diag::warn_arc_lifetime_result_type)
4668  << T.getQualifiers().getObjCLifetime();
4669  }
4670  }
4671 
4672  if (LangOpts.CPlusPlus && D.getDeclSpec().hasTagDefinition()) {
4673  // C++ [dcl.fct]p6:
4674  // Types shall not be defined in return or parameter types.
4675  TagDecl *Tag = cast<TagDecl>(D.getDeclSpec().getRepAsDecl());
4676  S.Diag(Tag->getLocation(), diag::err_type_defined_in_result_type)
4677  << Context.getTypeDeclType(Tag);
4678  }
4679 
4680  // Exception specs are not allowed in typedefs. Complain, but add it
4681  // anyway.
4682  if (IsTypedefName && FTI.getExceptionSpecType() && !LangOpts.CPlusPlus17)
4683  S.Diag(FTI.getExceptionSpecLocBeg(),
4684  diag::err_exception_spec_in_typedef)
4687 
4688  // If we see "T var();" or "T var(T());" at block scope, it is probably
4689  // an attempt to initialize a variable, not a function declaration.
4690  if (FTI.isAmbiguous)
4691  warnAboutAmbiguousFunction(S, D, DeclType, T);
4692 
4694  getCCForDeclaratorChunk(S, D, DeclType.getAttrs(), FTI, chunkIndex));
4695 
4696  if (!FTI.NumParams && !FTI.isVariadic && !LangOpts.CPlusPlus
4697  && !LangOpts.OpenCL) {
4698  // Simple void foo(), where the incoming T is the result type.
4699  T = Context.getFunctionNoProtoType(T, EI);
4700  } else {
4701  // We allow a zero-parameter variadic function in C if the
4702  // function is marked with the "overloadable" attribute. Scan
4703  // for this attribute now.
4704  if (!FTI.NumParams && FTI.isVariadic && !LangOpts.CPlusPlus)
4705  if (!D.getAttributes().hasAttribute(ParsedAttr::AT_Overloadable))
4706  S.Diag(FTI.getEllipsisLoc(), diag::err_ellipsis_first_param);
4707 
4708  if (FTI.NumParams && FTI.Params[0].Param == nullptr) {
4709  // C99 6.7.5.3p3: Reject int(x,y,z) when it's not a function
4710  // definition.
4711  S.Diag(FTI.Params[0].IdentLoc,
4712  diag::err_ident_list_in_fn_declaration);
4713  D.setInvalidType(true);
4714  // Recover by creating a K&R-style function type.
4715  T = Context.getFunctionNoProtoType(T, EI);
4716  break;
4717  }
4718 
4720  EPI.ExtInfo = EI;
4721  EPI.Variadic = FTI.isVariadic;
4725  : 0);
4726  EPI.RefQualifier = !FTI.hasRefQualifier()? RQ_None
4728  : RQ_RValue;
4729 
4730  // Otherwise, we have a function with a parameter list that is
4731  // potentially variadic.
4732  SmallVector<QualType, 16> ParamTys;
4733  ParamTys.reserve(FTI.NumParams);
4734 
4736  ExtParameterInfos(FTI.NumParams);
4737  bool HasAnyInterestingExtParameterInfos = false;
4738 
4739  for (unsigned i = 0, e = FTI.NumParams; i != e; ++i) {
4740  ParmVarDecl *Param = cast<ParmVarDecl>(FTI.Params[i].Param);
4741  QualType ParamTy = Param->getType();
4742  assert(!ParamTy.isNull() && "Couldn't parse type?");
4743 
4744  // Look for 'void'. void is allowed only as a single parameter to a
4745  // function with no other parameters (C99 6.7.5.3p10). We record
4746  // int(void) as a FunctionProtoType with an empty parameter list.
4747  if (ParamTy->isVoidType()) {
4748  // If this is something like 'float(int, void)', reject it. 'void'
4749  // is an incomplete type (C99 6.2.5p19) and function decls cannot
4750  // have parameters of incomplete type.
4751  if (FTI.NumParams != 1 || FTI.isVariadic) {
4752  S.Diag(DeclType.Loc, diag::err_void_only_param);
4753  ParamTy = Context.IntTy;
4754  Param->setType(ParamTy);
4755  } else if (FTI.Params[i].Ident) {
4756  // Reject, but continue to parse 'int(void abc)'.
4757  S.Diag(FTI.Params[i].IdentLoc, diag::err_param_with_void_type);
4758  ParamTy = Context.IntTy;
4759  Param->setType(ParamTy);
4760  } else {
4761  // Reject, but continue to parse 'float(const void)'.
4762  if (ParamTy.hasQualifiers())
4763  S.Diag(DeclType.Loc, diag::err_void_param_qualified);
4764 
4765  // Do not add 'void' to the list.
4766  break;
4767  }
4768  } else if (ParamTy->isHalfType()) {
4769  // Disallow half FP parameters.
4770  // FIXME: This really should be in BuildFunctionType.
4771  if (S.getLangOpts().OpenCL) {
4772  if (!S.getOpenCLOptions().isEnabled("cl_khr_fp16")) {
4773  S.Diag(Param->getLocation(),
4774  diag::err_opencl_half_param) << ParamTy;
4775  D.setInvalidType();
4776  Param->setInvalidDecl();
4777  }
4778  } else if (!S.getLangOpts().HalfArgsAndReturns) {
4779  S.Diag(Param->getLocation(),
4780  diag::err_parameters_retval_cannot_have_fp16_type) << 0;
4781  D.setInvalidType();
4782  }
4783  } else if (!FTI.hasPrototype) {
4784  if (ParamTy->isPromotableIntegerType()) {
4785  ParamTy = Context.getPromotedIntegerType(ParamTy);
4786  Param->setKNRPromoted(true);
4787  } else if (const BuiltinType* BTy = ParamTy->getAs<BuiltinType>()) {
4788  if (BTy->getKind() == BuiltinType::Float) {
4789  ParamTy = Context.DoubleTy;
4790  Param->setKNRPromoted(true);
4791  }
4792  }
4793  }
4794 
4795  if (LangOpts.ObjCAutoRefCount && Param->hasAttr<NSConsumedAttr>()) {
4796  ExtParameterInfos[i] = ExtParameterInfos[i].withIsConsumed(true);
4797  HasAnyInterestingExtParameterInfos = true;
4798  }
4799 
4800  if (auto attr = Param->getAttr<ParameterABIAttr>()) {
4801  ExtParameterInfos[i] =
4802  ExtParameterInfos[i].withABI(attr->getABI());
4803  HasAnyInterestingExtParameterInfos = true;
4804  }
4805 
4806  if (Param->hasAttr<PassObjectSizeAttr>()) {
4807  ExtParameterInfos[i] = ExtParameterInfos[i].withHasPassObjectSize();
4808  HasAnyInterestingExtParameterInfos = true;
4809  }
4810 
4811  if (Param->hasAttr<NoEscapeAttr>()) {
4812  ExtParameterInfos[i] = ExtParameterInfos[i].withIsNoEscape(true);
4813  HasAnyInterestingExtParameterInfos = true;
4814  }
4815 
4816  ParamTys.push_back(ParamTy);
4817  }
4818 
4819  if (HasAnyInterestingExtParameterInfos) {
4820  EPI.ExtParameterInfos = ExtParameterInfos.data();
4821  checkExtParameterInfos(S, ParamTys, EPI,
4822  [&](unsigned i) { return FTI.Params[i].Param->getLocation(); });
4823  }
4824 
4825  SmallVector<QualType, 4> Exceptions;
4826  SmallVector<ParsedType, 2> DynamicExceptions;
4827  SmallVector<SourceRange, 2> DynamicExceptionRanges;
4828  Expr *NoexceptExpr = nullptr;
4829 
4830  if (FTI.getExceptionSpecType() == EST_Dynamic) {
4831  // FIXME: It's rather inefficient to have to split into two vectors
4832  // here.
4833  unsigned N = FTI.getNumExceptions();
4834  DynamicExceptions.reserve(N);
4835  DynamicExceptionRanges.reserve(N);
4836  for (unsigned I = 0; I != N; ++I) {
4837  DynamicExceptions.push_back(FTI.Exceptions[I].Ty);
4838  DynamicExceptionRanges.push_back(FTI.Exceptions[I].Range);
4839  }
4840  } else if (isComputedNoexcept(FTI.getExceptionSpecType())) {
4841  NoexceptExpr = FTI.NoexceptExpr;
4842  }
4843 
4845  FTI.getExceptionSpecType(),
4846  DynamicExceptions,
4847  DynamicExceptionRanges,
4848  NoexceptExpr,
4849  Exceptions,
4850  EPI.ExceptionSpec);
4851 
4852  // FIXME: Set address space from attrs for C++ mode here.
4853  // OpenCLCPlusPlus: A class member function has an address space.
4854  auto IsClassMember = [&]() {
4855  return (!state.getDeclarator().getCXXScopeSpec().isEmpty() &&
4856  state.getDeclarator()
4857  .getCXXScopeSpec()
4858  .getScopeRep()
4859  ->getKind() == NestedNameSpecifier::TypeSpec) ||
4860  state.getDeclarator().getContext() ==
4862  };
4863 
4864  if (state.getSema().getLangOpts().OpenCLCPlusPlus && IsClassMember()) {
4865  LangAS ASIdx = LangAS::Default;
4866  // Take address space attr if any and mark as invalid to avoid adding
4867  // them later while creating QualType.
4868  if (FTI.MethodQualifiers)
4869  for (ParsedAttr &attr : FTI.MethodQualifiers->getAttributes()) {
4870  LangAS ASIdxNew = attr.asOpenCLLangAS();
4871  if (DiagnoseMultipleAddrSpaceAttributes(S, ASIdx, ASIdxNew,
4872  attr.getLoc()))
4873  D.setInvalidType(true);
4874  else
4875  ASIdx = ASIdxNew;
4876  }
4877  // If a class member function's address space is not set, set it to
4878  // __generic.
4879  LangAS AS =
4880  (ASIdx == LangAS::Default ? LangAS::opencl_generic : ASIdx);
4881  EPI.TypeQuals.addAddressSpace(AS);
4882  }
4883  T = Context.getFunctionType(T, ParamTys, EPI);
4884  }
4885  break;
4886  }
4888  // The scope spec must refer to a class, or be dependent.
4889  CXXScopeSpec &SS = DeclType.Mem.Scope();
4890  QualType ClsType;
4891 
4892  // Handle pointer nullability.
4893  inferPointerNullability(SimplePointerKind::MemberPointer, DeclType.Loc,
4894  DeclType.EndLoc, DeclType.getAttrs());
4895 
4896  if (SS.isInvalid()) {
4897  // Avoid emitting extra errors if we already errored on the scope.
4898  D.setInvalidType(true);
4899  } else if (S.isDependentScopeSpecifier(SS) ||
4900  dyn_cast_or_null<CXXRecordDecl>(S.computeDeclContext(SS))) {
4901  NestedNameSpecifier *NNS = SS.getScopeRep();
4902  NestedNameSpecifier *NNSPrefix = NNS->getPrefix();
4903  switch (NNS->getKind()) {
4905  ClsType = Context.getDependentNameType(ETK_None, NNSPrefix,
4906  NNS->getAsIdentifier());
4907  break;
4908 
4913  llvm_unreachable("Nested-name-specifier must name a type");
4914 
4917  ClsType = QualType(NNS->getAsType(), 0);
4918  // Note: if the NNS has a prefix and ClsType is a nondependent
4919  // TemplateSpecializationType, then the NNS prefix is NOT included
4920  // in ClsType; hence we wrap ClsType into an ElaboratedType.
4921  // NOTE: in particular, no wrap occurs if ClsType already is an
4922  // Elaborated, DependentName, or DependentTemplateSpecialization.
4923  if (NNSPrefix && isa<TemplateSpecializationType>(NNS->getAsType()))
4924  ClsType = Context.getElaboratedType(ETK_None, NNSPrefix, ClsType);
4925  break;
4926  }
4927  } else {
4928  S.Diag(DeclType.Mem.Scope().getBeginLoc(),
4929  diag::err_illegal_decl_mempointer_in_nonclass)
4930  << (D.getIdentifier() ? D.getIdentifier()->getName() : "type name")
4931  << DeclType.Mem.Scope().getRange();
4932  D.setInvalidType(true);
4933  }
4934 
4935  if (!ClsType.isNull())
4936  T = S.BuildMemberPointerType(T, ClsType, DeclType.Loc,
4937  D.getIdentifier());
4938  if (T.isNull()) {
4939  T = Context.IntTy;
4940  D.setInvalidType(true);
4941  } else if (DeclType.Mem.TypeQuals) {
4942  T = S.BuildQualifiedType(T, DeclType.Loc, DeclType.Mem.TypeQuals);
4943  }
4944  break;
4945  }
4946 
4947  case DeclaratorChunk::Pipe: {
4948  T = S.BuildReadPipeType(T, DeclType.Loc);
4949  processTypeAttrs(state, T, TAL_DeclSpec,
4951  break;
4952  }
4953  }
4954 
4955  if (T.isNull()) {
4956  D.setInvalidType(true);
4957  T = Context.IntTy;
4958  }
4959 
4960  // See if there are any attributes on this declarator chunk.
4961  processTypeAttrs(state, T, TAL_DeclChunk, DeclType.getAttrs());
4962 
4963  if (DeclType.Kind != DeclaratorChunk::Paren) {
4964  if (ExpectNoDerefChunk) {
4965  if (!IsNoDerefableChunk(DeclType))
4966  S.Diag(DeclType.Loc, diag::warn_noderef_on_non_pointer_or_array);
4967  ExpectNoDerefChunk = false;
4968  }
4969 
4970  ExpectNoDerefChunk = state.didParseNoDeref();
4971  }
4972  }
4973 
4974  if (ExpectNoDerefChunk)
4975  S.Diag(state.getDeclarator().getBeginLoc(),
4976  diag::warn_noderef_on_non_pointer_or_array);
4977 
4978  // GNU warning -Wstrict-prototypes
4979  // Warn if a function declaration is without a prototype.
4980  // This warning is issued for all kinds of unprototyped function
4981  // declarations (i.e. function type typedef, function pointer etc.)
4982  // C99 6.7.5.3p14:
4983  // The empty list in a function declarator that is not part of a definition
4984  // of that function specifies that no information about the number or types
4985  // of the parameters is supplied.
4986  if (!LangOpts.CPlusPlus && D.getFunctionDefinitionKind() == FDK_Declaration) {
4987  bool IsBlock = false;
4988  for (const DeclaratorChunk &DeclType : D.type_objects()) {
4989  switch (DeclType.Kind) {
4991  IsBlock = true;
4992  break;
4994  const DeclaratorChunk::FunctionTypeInfo &FTI = DeclType.Fun;
4995  if (FTI.NumParams == 0 && !FTI.isVariadic)
4996  S.Diag(DeclType.Loc, diag::warn_strict_prototypes)
4997  << IsBlock
4998  << FixItHint::CreateInsertion(FTI.getRParenLoc(), "void");
4999  IsBlock = false;
5000  break;
5001  }
5002  default:
5003  break;
5004  }
5005  }
5006  }
5007 
5008  assert(!T.isNull() && "T must not be null after this point");
5009 
5010  if (LangOpts.CPlusPlus && T->isFunctionType()) {
5011  const FunctionProtoType *FnTy = T->getAs<FunctionProtoType>();
5012  assert(FnTy && "Why oh why is there not a FunctionProtoType here?");
5013 
5014  // C++ 8.3.5p4:
5015  // A cv-qualifier-seq shall only be part of the function type
5016  // for a nonstatic member function, the function type to which a pointer
5017  // to member refers, or the top-level function type of a function typedef
5018  // declaration.
5019  //
5020  // Core issue 547 also allows cv-qualifiers on function types that are
5021  // top-level template type arguments.
5022  enum { NonMember, Member, DeductionGuide } Kind = NonMember;
5024  Kind = DeductionGuide;
5025  else if (!D.getCXXScopeSpec().isSet()) {
5029  Kind = Member;
5030  } else {
5032  if (!DC || DC->isRecord())
5033  Kind = Member;
5034  }
5035 
5036  // C++11 [dcl.fct]p6 (w/DR1417):
5037  // An attempt to specify a function type with a cv-qualifier-seq or a
5038  // ref-qualifier (including by typedef-name) is ill-formed unless it is:
5039  // - the function type for a non-static member function,
5040  // - the function type to which a pointer to member refers,
5041  // - the top-level function type of a function typedef declaration or
5042  // alias-declaration,
5043  // - the type-id in the default argument of a type-parameter, or
5044  // - the type-id of a template-argument for a type-parameter
5045  //
5046  // FIXME: Checking this here is insufficient. We accept-invalid on:
5047  //
5048  // template<typename T> struct S { void f(T); };
5049  // S<int() const> s;
5050  //
5051  // ... for instance.
5052  if (IsQualifiedFunction &&
5053  !(Kind == Member &&
5055  !IsTypedefName &&
5058  SourceLocation Loc = D.getBeginLoc();
5059  SourceRange RemovalRange;
5060  unsigned I;
5061  if (D.isFunctionDeclarator(I)) {
5062  SmallVector<SourceLocation, 4> RemovalLocs;
5063  const DeclaratorChunk &Chunk = D.getTypeObject(I);
5064  assert(Chunk.Kind == DeclaratorChunk::Function);
5065 
5066  if (Chunk.Fun.hasRefQualifier())
5067  RemovalLocs.push_back(Chunk.Fun.getRefQualifierLoc());
5068 
5069  if (Chunk.Fun.hasMethodTypeQualifiers())
5071  [&](DeclSpec::TQ TypeQual, StringRef QualName,
5072  SourceLocation SL) { RemovalLocs.push_back(SL); });
5073 
5074  if (!RemovalLocs.empty()) {
5075  llvm::sort(RemovalLocs,
5077  RemovalRange = SourceRange(RemovalLocs.front(), RemovalLocs.back());
5078  Loc = RemovalLocs.front();
5079  }
5080  }
5081 
5082  S.Diag(Loc, diag::err_invalid_qualified_function_type)
5083  << Kind << D.isFunctionDeclarator() << T
5085  << FixItHint::CreateRemoval(RemovalRange);
5086 
5087  // Strip the cv-qualifiers and ref-qualifiers from the type.
5090  EPI.RefQualifier = RQ_None;
5091 
5092  T = Context.getFunctionType(FnTy->getReturnType(), FnTy->getParamTypes(),
5093  EPI);
5094  // Rebuild any parens around the identifier in the function type.
5095  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
5097  break;
5098  T = S.BuildParenType(T);
5099  }
5100  }
5101  }
5102 
5103  // Apply any undistributed attributes from the declarator.
5105 
5106  // Diagnose any ignored type attributes.
5107  state.diagnoseIgnoredTypeAttrs(T);
5108 
5109  // C++0x [dcl.constexpr]p9:
5110  // A constexpr specifier used in an object declaration declares the object
5111  // as const.
5112  if (D.getDeclSpec().isConstexprSpecified() && T->isObjectType()) {
5113  T.addConst();
5114  }
5115 
5116  // If there was an ellipsis in the declarator, the declaration declares a
5117  // parameter pack whose type may be a pack expansion type.
5118  if (D.hasEllipsis()) {
5119  // C++0x [dcl.fct]p13:
5120  // A declarator-id or abstract-declarator containing an ellipsis shall
5121  // only be used in a parameter-declaration. Such a parameter-declaration
5122  // is a parameter pack (14.5.3). [...]
5123  switch (D.getContext()) {
5126  // C++0x [dcl.fct]p13:
5127  // [...] When it is part of a parameter-declaration-clause, the
5128  // parameter pack is a function parameter pack (14.5.3). The type T
5129  // of the declarator-id of the function parameter pack shall contain
5130  // a template parameter pack; each template parameter pack in T is
5131  // expanded by the function parameter pack.
5132  //
5133  // We represent function parameter packs as function parameters whose
5134  // type is a pack expansion.
5135  if (!T->containsUnexpandedParameterPack()) {
5136  S.Diag(D.getEllipsisLoc(),
5137  diag::err_function_parameter_pack_without_parameter_packs)
5138  << T << D.getSourceRange();
5140  } else {
5141  T = Context.getPackExpansionType(T, None);
5142  }
5143  break;
5145  // C++0x [temp.param]p15:
5146  // If a template-parameter is a [...] is a parameter-declaration that
5147  // declares a parameter pack (8.3.5), then the template-parameter is a
5148  // template parameter pack (14.5.3).
5149  //
5150  // Note: core issue 778 clarifies that, if there are any unexpanded
5151  // parameter packs in the type of the non-type template parameter, then
5152  // it expands those parameter packs.
5154  T = Context.getPackExpansionType(T, None);
5155  else
5156  S.Diag(D.getEllipsisLoc(),
5157  LangOpts.CPlusPlus11
5158  ? diag::warn_cxx98_compat_variadic_templates
5159  : diag::ext_variadic_templates);
5160  break;
5161 
5164  case DeclaratorContext::ObjCParameterContext: // FIXME: special diagnostic
5165  // here?
5166  case DeclaratorContext::ObjCResultContext: // FIXME: special diagnostic
5167  // here?
5187  // FIXME: We may want to allow parameter packs in block-literal contexts
5188  // in the future.
5189  S.Diag(D.getEllipsisLoc(),
5190  diag::err_ellipsis_in_declarator_not_parameter);
5192  break;
5193  }
5194  }
5195 
5196  assert(!T.isNull() && "T must not be null at the end of this function");
5197  if (D.isInvalidType())
5198  return Context.getTrivialTypeSourceInfo(T);
5199 
5200  return GetTypeSourceInfoForDeclarator(state, T, TInfo);
5201 }
5202 
5203 /// GetTypeForDeclarator - Convert the type for the specified
5204 /// declarator to Type instances.
5205 ///
5206 /// The result of this call will never be null, but the associated
5207 /// type may be a null type if there's an unrecoverable error.
5209  // Determine the type of the declarator. Not all forms of declarator
5210  // have a type.
5211 
5212  TypeProcessingState state(*this, D);
5213 
5214  TypeSourceInfo *ReturnTypeInfo = nullptr;
5215  QualType T = GetDeclSpecTypeForDeclarator(state, ReturnTypeInfo);
5216  if (D.isPrototypeContext() && getLangOpts().ObjCAutoRefCount)
5217  inferARCWriteback(state, T);
5218 
5219  return GetFullTypeForDeclarator(state, T, ReturnTypeInfo);
5220 }
5221 
5223  QualType &declSpecTy,
5224  Qualifiers::ObjCLifetime ownership) {
5225  if (declSpecTy->isObjCRetainableType() &&
5226  declSpecTy.getObjCLifetime() == Qualifiers::OCL_None) {
5227  Qualifiers qs;
5228  qs.addObjCLifetime(ownership);
5229  declSpecTy = S.Context.getQualifiedType(declSpecTy, qs);
5230  }
5231 }
5232 
5233 static void transferARCOwnershipToDeclaratorChunk(TypeProcessingState &state,
5234  Qualifiers::ObjCLifetime ownership,
5235  unsigned chunkIndex) {
5236  Sema &S = state.getSema();
5237  Declarator &D = state.getDeclarator();
5238 
5239  // Look for an explicit lifetime attribute.
5240  DeclaratorChunk &chunk = D.getTypeObject(chunkIndex);
5241  if (chunk.getAttrs().hasAttribute(ParsedAttr::AT_ObjCOwnership))
5242  return;
5243 
5244  const char *attrStr = nullptr;
5245  switch (ownership) {
5246  case Qualifiers::OCL_None: llvm_unreachable("no ownership!");
5247  case Qualifiers::OCL_ExplicitNone: attrStr = "none"; break;
5248  case Qualifiers::OCL_Strong: attrStr = "strong"; break;
5249  case Qualifiers::OCL_Weak: attrStr = "weak"; break;
5250  case Qualifiers::OCL_Autoreleasing: attrStr = "autoreleasing"; break;
5251  }
5252 
5253  IdentifierLoc *Arg = new (S.Context) IdentifierLoc;
5254  Arg->Ident = &S.Context.Idents.get(attrStr);
5255  Arg->Loc = SourceLocation();
5256 
5257  ArgsUnion Args(Arg);
5258 
5259  // If there wasn't one, add one (with an invalid source location
5260  // so that we don't make an AttributedType for it).
5261  ParsedAttr *attr = D.getAttributePool().create(
5262  &S.Context.Idents.get("objc_ownership"), SourceLocation(),
5263  /*scope*/ nullptr, SourceLocation(),
5264  /*args*/ &Args, 1, ParsedAttr::AS_GNU);
5265  chunk.getAttrs().addAtEnd(attr);
5266  // TODO: mark whether we did this inference?
5267 }
5268 
5269 /// Used for transferring ownership in casts resulting in l-values.
5270 static void transferARCOwnership(TypeProcessingState &state,
5271  QualType &declSpecTy,
5272  Qualifiers::ObjCLifetime ownership) {
5273  Sema &S = state.getSema();
5274  Declarator &D = state.getDeclarator();
5275 
5276  int inner = -1;
5277  bool hasIndirection = false;
5278  for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
5279  DeclaratorChunk &chunk = D.getTypeObject(i);
5280  switch (chunk.Kind) {
5282  // Ignore parens.
5283  break;
5284 
5288  if (inner != -1)
5289  hasIndirection = true;
5290  inner = i;
5291  break;
5292 
5294  if (inner != -1)
5295  transferARCOwnershipToDeclaratorChunk(state, ownership, i);
5296  return;
5297 
5300  case DeclaratorChunk::Pipe:
5301  return;
5302  }
5303  }
5304 
5305  if (inner == -1)
5306  return;
5307 
5308  DeclaratorChunk &chunk = D.getTypeObject(inner);
5309  if (chunk.Kind == DeclaratorChunk::Pointer) {
5310  if (declSpecTy->isObjCRetainableType())
5311  return transferARCOwnershipToDeclSpec(S, declSpecTy, ownership);
5312  if (declSpecTy->isObjCObjectType() && hasIndirection)
5313  return transferARCOwnershipToDeclaratorChunk(state, ownership, inner);
5314  } else {
5315  assert(chunk.Kind == DeclaratorChunk::Array ||
5316  chunk.Kind == DeclaratorChunk::Reference);
5317  return transferARCOwnershipToDeclSpec(S, declSpecTy, ownership);
5318  }
5319 }
5320 
5322  TypeProcessingState state(*this, D);
5323 
5324  TypeSourceInfo *ReturnTypeInfo = nullptr;
5325  QualType declSpecTy = GetDeclSpecTypeForDeclarator(state, ReturnTypeInfo);
5326 
5327  if (getLangOpts().ObjC) {
5328  Qualifiers::ObjCLifetime ownership = Context.getInnerObjCOwnership(FromTy);
5329  if (ownership != Qualifiers::OCL_None)
5330  transferARCOwnership(state, declSpecTy, ownership);
5331  }
5332 
5333  return GetFullTypeForDeclarator(state, declSpecTy, ReturnTypeInfo);
5334 }
5335 
5337  TypeProcessingState &State) {
5338  TL.setAttr(State.takeAttrForAttributedType(TL.getTypePtr()));
5339 }
5340 
5341 namespace {
5342  class TypeSpecLocFiller : public TypeLocVisitor<TypeSpecLocFiller> {
5343  ASTContext &Context;
5344  TypeProcessingState &State;
5345  const DeclSpec &DS;
5346 
5347  public:
5348  TypeSpecLocFiller(ASTContext &Context, TypeProcessingState &State,
5349  const DeclSpec &DS)
5350  : Context(Context), State(State), DS(DS) {}
5351 
5352  void VisitAttributedTypeLoc(AttributedTypeLoc TL) {
5353  Visit(TL.getModifiedLoc());
5354  fillAttributedTypeLoc(TL, State);
5355  }
5356  void VisitQualifiedTypeLoc(QualifiedTypeLoc TL) {
5357  Visit(TL.getUnqualifiedLoc());
5358  }
5359  void VisitTypedefTypeLoc(TypedefTypeLoc TL) {
5360  TL.setNameLoc(DS.getTypeSpecTypeLoc());
5361  }
5362  void VisitObjCInterfaceTypeLoc(ObjCInterfaceTypeLoc TL) {
5363  TL.setNameLoc(DS.getTypeSpecTypeLoc());
5364  // FIXME. We should have DS.getTypeSpecTypeEndLoc(). But, it requires
5365  // addition field. What we have is good enough for dispay of location
5366  // of 'fixit' on interface name.
5367  TL.setNameEndLoc(DS.getEndLoc());
5368  }
5369  void VisitObjCObjectTypeLoc(ObjCObjectTypeLoc TL) {
5370  TypeSourceInfo *RepTInfo = nullptr;
5371  Sema::GetTypeFromParser(DS.getRepAsType(), &RepTInfo);
5372  TL.copy(RepTInfo->getTypeLoc());
5373  }
5374  void VisitObjCObjectPointerTypeLoc(ObjCObjectPointerTypeLoc TL) {
5375  TypeSourceInfo *RepTInfo = nullptr;
5376  Sema::GetTypeFromParser(DS.getRepAsType(), &RepTInfo);
5377  TL.copy(RepTInfo->getTypeLoc());
5378  }
5379  void VisitTemplateSpecializationTypeLoc(TemplateSpecializationTypeLoc TL) {
5380  TypeSourceInfo *TInfo = nullptr;
5381  Sema::GetTypeFromParser(DS.getRepAsType(), &TInfo);
5382 
5383  // If we got no declarator info from previous Sema routines,
5384  // just fill with the typespec loc.
5385  if (!TInfo) {
5386  TL.initialize(Context, DS.getTypeSpecTypeNameLoc());
5387  return;
5388  }
5389 
5390  TypeLo