SemaDeclAttr.cpp revision 7e112c08271699fbf86167bc9973cdbaa3748da9 
1//===--- SemaDeclAttr.cpp - Declaration Attribute Handling ----------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements decl-related attribute processing.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Sema/SemaInternal.h"
15#include "TargetAttributesSema.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/DeclCXX.h"
18#include "clang/AST/DeclObjC.h"
19#include "clang/AST/Expr.h"
20#include "clang/Basic/TargetInfo.h"
21#include "clang/Sema/DeclSpec.h"
22#include "clang/Sema/DelayedDiagnostic.h"
23#include "llvm/ADT/StringExtras.h"
24using namespace clang;
25using namespace sema;
26
27//===----------------------------------------------------------------------===//
28//  Helper functions
29//===----------------------------------------------------------------------===//
30
31static const FunctionType *getFunctionType(const Decl *d,
32                                           bool blocksToo = true) {
33  QualType Ty;
34  if (const ValueDecl *decl = dyn_cast<ValueDecl>(d))
35    Ty = decl->getType();
36  else if (const FieldDecl *decl = dyn_cast<FieldDecl>(d))
37    Ty = decl->getType();
38  else if (const TypedefDecl* decl = dyn_cast<TypedefDecl>(d))
39    Ty = decl->getUnderlyingType();
40  else
41    return 0;
42
43  if (Ty->isFunctionPointerType())
44    Ty = Ty->getAs<PointerType>()->getPointeeType();
45  else if (blocksToo && Ty->isBlockPointerType())
46    Ty = Ty->getAs<BlockPointerType>()->getPointeeType();
47
48  return Ty->getAs<FunctionType>();
49}
50
51// FIXME: We should provide an abstraction around a method or function
52// to provide the following bits of information.
53
54/// isFunction - Return true if the given decl has function
55/// type (function or function-typed variable).
56static bool isFunction(const Decl *d) {
57  return getFunctionType(d, false) != NULL;
58}
59
60/// isFunctionOrMethod - Return true if the given decl has function
61/// type (function or function-typed variable) or an Objective-C
62/// method.
63static bool isFunctionOrMethod(const Decl *d) {
64  return isFunction(d)|| isa<ObjCMethodDecl>(d);
65}
66
67/// isFunctionOrMethodOrBlock - Return true if the given decl has function
68/// type (function or function-typed variable) or an Objective-C
69/// method or a block.
70static bool isFunctionOrMethodOrBlock(const Decl *d) {
71  if (isFunctionOrMethod(d))
72    return true;
73  // check for block is more involved.
74  if (const VarDecl *V = dyn_cast<VarDecl>(d)) {
75    QualType Ty = V->getType();
76    return Ty->isBlockPointerType();
77  }
78  return isa<BlockDecl>(d);
79}
80
81/// hasFunctionProto - Return true if the given decl has a argument
82/// information. This decl should have already passed
83/// isFunctionOrMethod or isFunctionOrMethodOrBlock.
84static bool hasFunctionProto(const Decl *d) {
85  if (const FunctionType *FnTy = getFunctionType(d))
86    return isa<FunctionProtoType>(FnTy);
87  else {
88    assert(isa<ObjCMethodDecl>(d) || isa<BlockDecl>(d));
89    return true;
90  }
91}
92
93/// getFunctionOrMethodNumArgs - Return number of function or method
94/// arguments. It is an error to call this on a K&R function (use
95/// hasFunctionProto first).
96static unsigned getFunctionOrMethodNumArgs(const Decl *d) {
97  if (const FunctionType *FnTy = getFunctionType(d))
98    return cast<FunctionProtoType>(FnTy)->getNumArgs();
99  if (const BlockDecl *BD = dyn_cast<BlockDecl>(d))
100    return BD->getNumParams();
101  return cast<ObjCMethodDecl>(d)->param_size();
102}
103
104static QualType getFunctionOrMethodArgType(const Decl *d, unsigned Idx) {
105  if (const FunctionType *FnTy = getFunctionType(d))
106    return cast<FunctionProtoType>(FnTy)->getArgType(Idx);
107  if (const BlockDecl *BD = dyn_cast<BlockDecl>(d))
108    return BD->getParamDecl(Idx)->getType();
109
110  return cast<ObjCMethodDecl>(d)->param_begin()[Idx]->getType();
111}
112
113static QualType getFunctionOrMethodResultType(const Decl *d) {
114  if (const FunctionType *FnTy = getFunctionType(d))
115    return cast<FunctionProtoType>(FnTy)->getResultType();
116  return cast<ObjCMethodDecl>(d)->getResultType();
117}
118
119static bool isFunctionOrMethodVariadic(const Decl *d) {
120  if (const FunctionType *FnTy = getFunctionType(d)) {
121    const FunctionProtoType *proto = cast<FunctionProtoType>(FnTy);
122    return proto->isVariadic();
123  } else if (const BlockDecl *BD = dyn_cast<BlockDecl>(d))
124    return BD->isVariadic();
125  else {
126    return cast<ObjCMethodDecl>(d)->isVariadic();
127  }
128}
129
130static bool isInstanceMethod(const Decl *d) {
131  if (const CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(d))
132    return MethodDecl->isInstance();
133  return false;
134}
135
136static inline bool isNSStringType(QualType T, ASTContext &Ctx) {
137  const ObjCObjectPointerType *PT = T->getAs<ObjCObjectPointerType>();
138  if (!PT)
139    return false;
140
141  ObjCInterfaceDecl *Cls = PT->getObjectType()->getInterface();
142  if (!Cls)
143    return false;
144
145  IdentifierInfo* ClsName = Cls->getIdentifier();
146
147  // FIXME: Should we walk the chain of classes?
148  return ClsName == &Ctx.Idents.get("NSString") ||
149         ClsName == &Ctx.Idents.get("NSMutableString");
150}
151
152static inline bool isCFStringType(QualType T, ASTContext &Ctx) {
153  const PointerType *PT = T->getAs<PointerType>();
154  if (!PT)
155    return false;
156
157  const RecordType *RT = PT->getPointeeType()->getAs<RecordType>();
158  if (!RT)
159    return false;
160
161  const RecordDecl *RD = RT->getDecl();
162  if (RD->getTagKind() != TTK_Struct)
163    return false;
164
165  return RD->getIdentifier() == &Ctx.Idents.get("__CFString");
166}
167
168//===----------------------------------------------------------------------===//
169// Attribute Implementations
170//===----------------------------------------------------------------------===//
171
172// FIXME: All this manual attribute parsing code is gross. At the
173// least add some helper functions to check most argument patterns (#
174// and types of args).
175
176static void HandleExtVectorTypeAttr(Scope *scope, Decl *d,
177                                    const AttributeList &Attr, Sema &S) {
178  TypedefDecl *tDecl = dyn_cast<TypedefDecl>(d);
179  if (tDecl == 0) {
180    S.Diag(Attr.getLoc(), diag::err_typecheck_ext_vector_not_typedef);
181    return;
182  }
183
184  QualType curType = tDecl->getUnderlyingType();
185
186  Expr *sizeExpr;
187
188  // Special case where the argument is a template id.
189  if (Attr.getParameterName()) {
190    CXXScopeSpec SS;
191    UnqualifiedId id;
192    id.setIdentifier(Attr.getParameterName(), Attr.getLoc());
193    sizeExpr = S.ActOnIdExpression(scope, SS, id, false, false).takeAs<Expr>();
194  } else {
195    // check the attribute arguments.
196    if (Attr.getNumArgs() != 1) {
197      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
198      return;
199    }
200    sizeExpr = Attr.getArg(0);
201  }
202
203  // Instantiate/Install the vector type, and let Sema build the type for us.
204  // This will run the reguired checks.
205  QualType T = S.BuildExtVectorType(curType, sizeExpr, Attr.getLoc());
206  if (!T.isNull()) {
207    // FIXME: preserve the old source info.
208    tDecl->setTypeSourceInfo(S.Context.getTrivialTypeSourceInfo(T));
209
210    // Remember this typedef decl, we will need it later for diagnostics.
211    S.ExtVectorDecls.push_back(tDecl);
212  }
213}
214
215static void HandlePackedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
216  // check the attribute arguments.
217  if (Attr.getNumArgs() > 0) {
218    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
219    return;
220  }
221
222  if (TagDecl *TD = dyn_cast<TagDecl>(d))
223    TD->addAttr(::new (S.Context) PackedAttr(Attr.getLoc(), S.Context));
224  else if (FieldDecl *FD = dyn_cast<FieldDecl>(d)) {
225    // If the alignment is less than or equal to 8 bits, the packed attribute
226    // has no effect.
227    if (!FD->getType()->isIncompleteType() &&
228        S.Context.getTypeAlign(FD->getType()) <= 8)
229      S.Diag(Attr.getLoc(), diag::warn_attribute_ignored_for_field_of_type)
230        << Attr.getName() << FD->getType();
231    else
232      FD->addAttr(::new (S.Context) PackedAttr(Attr.getLoc(), S.Context));
233  } else
234    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
235}
236
237static void HandleIBAction(Decl *d, const AttributeList &Attr, Sema &S) {
238  // check the attribute arguments.
239  if (Attr.getNumArgs() > 0) {
240    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
241    return;
242  }
243
244  // The IBAction attributes only apply to instance methods.
245  if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(d))
246    if (MD->isInstanceMethod()) {
247      d->addAttr(::new (S.Context) IBActionAttr(Attr.getLoc(), S.Context));
248      return;
249    }
250
251  S.Diag(Attr.getLoc(), diag::err_attribute_ibaction) << Attr.getName();
252}
253
254static void HandleIBOutlet(Decl *d, const AttributeList &Attr, Sema &S) {
255  // check the attribute arguments.
256  if (Attr.getNumArgs() > 0) {
257    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
258    return;
259  }
260
261  // The IBOutlet attributes only apply to instance variables of
262  // Objective-C classes.
263  if (isa<ObjCIvarDecl>(d) || isa<ObjCPropertyDecl>(d)) {
264    d->addAttr(::new (S.Context) IBOutletAttr(Attr.getLoc(), S.Context));
265    return;
266  }
267
268  S.Diag(Attr.getLoc(), diag::err_attribute_iboutlet) << Attr.getName();
269}
270
271static void HandleIBOutletCollection(Decl *d, const AttributeList &Attr,
272                                     Sema &S) {
273
274  // The iboutletcollection attribute can have zero or one arguments.
275  if (Attr.getParameterName() && Attr.getNumArgs() > 0) {
276    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
277    return;
278  }
279
280  // The IBOutletCollection attributes only apply to instance variables of
281  // Objective-C classes.
282  if (!(isa<ObjCIvarDecl>(d) || isa<ObjCPropertyDecl>(d))) {
283    S.Diag(Attr.getLoc(), diag::err_attribute_iboutlet) << Attr.getName();
284    return;
285  }
286  if (const ValueDecl *VD = dyn_cast<ValueDecl>(d))
287    if (!VD->getType()->getAs<ObjCObjectPointerType>()) {
288      S.Diag(Attr.getLoc(), diag::err_iboutletcollection_object_type)
289        << VD->getType() << 0;
290      return;
291    }
292  if (const ObjCPropertyDecl *PD = dyn_cast<ObjCPropertyDecl>(d))
293    if (!PD->getType()->getAs<ObjCObjectPointerType>()) {
294      S.Diag(Attr.getLoc(), diag::err_iboutletcollection_object_type)
295        << PD->getType() << 1;
296      return;
297    }
298
299  IdentifierInfo *II = Attr.getParameterName();
300  if (!II)
301    II = &S.Context.Idents.get("id");
302
303  ParsedType TypeRep = S.getTypeName(*II, Attr.getLoc(),
304                        S.getScopeForContext(d->getDeclContext()->getParent()));
305  if (!TypeRep) {
306    S.Diag(Attr.getLoc(), diag::err_iboutletcollection_type) << II;
307    return;
308  }
309  QualType QT = TypeRep.get();
310  // Diagnose use of non-object type in iboutletcollection attribute.
311  // FIXME. Gnu attribute extension ignores use of builtin types in
312  // attributes. So, __attribute__((iboutletcollection(char))) will be
313  // treated as __attribute__((iboutletcollection())).
314  if (!QT->isObjCIdType() && !QT->isObjCClassType() &&
315      !QT->isObjCObjectType()) {
316    S.Diag(Attr.getLoc(), diag::err_iboutletcollection_type) << II;
317    return;
318  }
319  d->addAttr(::new (S.Context) IBOutletCollectionAttr(Attr.getLoc(), S.Context,
320                                                      QT));
321}
322
323static void HandleNonNullAttr(Decl *d, const AttributeList &Attr, Sema &S) {
324  // GCC ignores the nonnull attribute on K&R style function prototypes, so we
325  // ignore it as well
326  if (!isFunctionOrMethod(d) || !hasFunctionProto(d)) {
327    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
328      << Attr.getName() << 0 /*function*/;
329    return;
330  }
331
332  // In C++ the implicit 'this' function parameter also counts, and they are
333  // counted from one.
334  bool HasImplicitThisParam = isInstanceMethod(d);
335  unsigned NumArgs  = getFunctionOrMethodNumArgs(d) + HasImplicitThisParam;
336
337  // The nonnull attribute only applies to pointers.
338  llvm::SmallVector<unsigned, 10> NonNullArgs;
339
340  for (AttributeList::arg_iterator I=Attr.arg_begin(),
341                                   E=Attr.arg_end(); I!=E; ++I) {
342
343
344    // The argument must be an integer constant expression.
345    Expr *Ex = *I;
346    llvm::APSInt ArgNum(32);
347    if (Ex->isTypeDependent() || Ex->isValueDependent() ||
348        !Ex->isIntegerConstantExpr(ArgNum, S.Context)) {
349      S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
350        << "nonnull" << Ex->getSourceRange();
351      return;
352    }
353
354    unsigned x = (unsigned) ArgNum.getZExtValue();
355
356    if (x < 1 || x > NumArgs) {
357      S.Diag(Attr.getLoc(), diag::err_attribute_argument_out_of_bounds)
358       << "nonnull" << I.getArgNum() << Ex->getSourceRange();
359      return;
360    }
361
362    --x;
363    if (HasImplicitThisParam) {
364      if (x == 0) {
365        S.Diag(Attr.getLoc(),
366               diag::err_attribute_invalid_implicit_this_argument)
367          << "nonnull" << Ex->getSourceRange();
368        return;
369      }
370      --x;
371    }
372
373    // Is the function argument a pointer type?
374    QualType T = getFunctionOrMethodArgType(d, x);
375    if (!T->isAnyPointerType() && !T->isBlockPointerType()) {
376      // FIXME: Should also highlight argument in decl.
377      S.Diag(Attr.getLoc(), diag::warn_nonnull_pointers_only)
378        << "nonnull" << Ex->getSourceRange();
379      continue;
380    }
381
382    NonNullArgs.push_back(x);
383  }
384
385  // If no arguments were specified to __attribute__((nonnull)) then all pointer
386  // arguments have a nonnull attribute.
387  if (NonNullArgs.empty()) {
388    for (unsigned I = 0, E = getFunctionOrMethodNumArgs(d); I != E; ++I) {
389      QualType T = getFunctionOrMethodArgType(d, I);
390      if (T->isAnyPointerType() || T->isBlockPointerType())
391        NonNullArgs.push_back(I);
392      else if (const RecordType *UT = T->getAsUnionType()) {
393        if (UT && UT->getDecl()->hasAttr<TransparentUnionAttr>()) {
394          RecordDecl *UD = UT->getDecl();
395          for (RecordDecl::field_iterator it = UD->field_begin(),
396               itend = UD->field_end(); it != itend; ++it) {
397            T = it->getType();
398            if (T->isAnyPointerType() || T->isBlockPointerType()) {
399              NonNullArgs.push_back(I);
400              break;
401            }
402          }
403        }
404      }
405    }
406
407    // No pointer arguments?
408    if (NonNullArgs.empty()) {
409      // Warn the trivial case only if attribute is not coming from a
410      // macro instantiation.
411      if (Attr.getLoc().isFileID())
412        S.Diag(Attr.getLoc(), diag::warn_attribute_nonnull_no_pointers);
413      return;
414    }
415  }
416
417  unsigned* start = &NonNullArgs[0];
418  unsigned size = NonNullArgs.size();
419  llvm::array_pod_sort(start, start + size);
420  d->addAttr(::new (S.Context) NonNullAttr(Attr.getLoc(), S.Context, start,
421                                           size));
422}
423
424static void HandleOwnershipAttr(Decl *d, const AttributeList &AL, Sema &S) {
425  // This attribute must be applied to a function declaration.
426  // The first argument to the attribute must be a string,
427  // the name of the resource, for example "malloc".
428  // The following arguments must be argument indexes, the arguments must be
429  // of integer type for Returns, otherwise of pointer type.
430  // The difference between Holds and Takes is that a pointer may still be used
431  // after being held.  free() should be __attribute((ownership_takes)), whereas
432  // a list append function may well be __attribute((ownership_holds)).
433
434  if (!AL.getParameterName()) {
435    S.Diag(AL.getLoc(), diag::err_attribute_argument_n_not_string)
436        << AL.getName()->getName() << 1;
437    return;
438  }
439  // Figure out our Kind, and check arguments while we're at it.
440  OwnershipAttr::OwnershipKind K;
441  switch (AL.getKind()) {
442  case AttributeList::AT_ownership_takes:
443    K = OwnershipAttr::Takes;
444    if (AL.getNumArgs() < 1) {
445      S.Diag(AL.getLoc(), diag::err_attribute_wrong_number_arguments) << 2;
446      return;
447    }
448    break;
449  case AttributeList::AT_ownership_holds:
450    K = OwnershipAttr::Holds;
451    if (AL.getNumArgs() < 1) {
452      S.Diag(AL.getLoc(), diag::err_attribute_wrong_number_arguments) << 2;
453      return;
454    }
455    break;
456  case AttributeList::AT_ownership_returns:
457    K = OwnershipAttr::Returns;
458    if (AL.getNumArgs() > 1) {
459      S.Diag(AL.getLoc(), diag::err_attribute_wrong_number_arguments)
460          << AL.getNumArgs() + 1;
461      return;
462    }
463    break;
464  default:
465    // This should never happen given how we are called.
466    llvm_unreachable("Unknown ownership attribute");
467  }
468
469  if (!isFunction(d) || !hasFunctionProto(d)) {
470    S.Diag(AL.getLoc(), diag::warn_attribute_wrong_decl_type) << AL.getName()
471        << 0 /*function*/;
472    return;
473  }
474
475  // In C++ the implicit 'this' function parameter also counts, and they are
476  // counted from one.
477  bool HasImplicitThisParam = isInstanceMethod(d);
478  unsigned NumArgs  = getFunctionOrMethodNumArgs(d) + HasImplicitThisParam;
479
480  llvm::StringRef Module = AL.getParameterName()->getName();
481
482  // Normalize the argument, __foo__ becomes foo.
483  if (Module.startswith("__") && Module.endswith("__"))
484    Module = Module.substr(2, Module.size() - 4);
485
486  llvm::SmallVector<unsigned, 10> OwnershipArgs;
487
488  for (AttributeList::arg_iterator I = AL.arg_begin(), E = AL.arg_end(); I != E;
489       ++I) {
490
491    Expr *IdxExpr = *I;
492    llvm::APSInt ArgNum(32);
493    if (IdxExpr->isTypeDependent() || IdxExpr->isValueDependent()
494        || !IdxExpr->isIntegerConstantExpr(ArgNum, S.Context)) {
495      S.Diag(AL.getLoc(), diag::err_attribute_argument_not_int)
496          << AL.getName()->getName() << IdxExpr->getSourceRange();
497      continue;
498    }
499
500    unsigned x = (unsigned) ArgNum.getZExtValue();
501
502    if (x > NumArgs || x < 1) {
503      S.Diag(AL.getLoc(), diag::err_attribute_argument_out_of_bounds)
504          << AL.getName()->getName() << x << IdxExpr->getSourceRange();
505      continue;
506    }
507    --x;
508    if (HasImplicitThisParam) {
509      if (x == 0) {
510        S.Diag(AL.getLoc(), diag::err_attribute_invalid_implicit_this_argument)
511          << "ownership" << IdxExpr->getSourceRange();
512        return;
513      }
514      --x;
515    }
516
517    switch (K) {
518    case OwnershipAttr::Takes:
519    case OwnershipAttr::Holds: {
520      // Is the function argument a pointer type?
521      QualType T = getFunctionOrMethodArgType(d, x);
522      if (!T->isAnyPointerType() && !T->isBlockPointerType()) {
523        // FIXME: Should also highlight argument in decl.
524        S.Diag(AL.getLoc(), diag::err_ownership_type)
525            << ((K==OwnershipAttr::Takes)?"ownership_takes":"ownership_holds")
526            << "pointer"
527            << IdxExpr->getSourceRange();
528        continue;
529      }
530      break;
531    }
532    case OwnershipAttr::Returns: {
533      if (AL.getNumArgs() > 1) {
534          // Is the function argument an integer type?
535          Expr *IdxExpr = AL.getArg(0);
536          llvm::APSInt ArgNum(32);
537          if (IdxExpr->isTypeDependent() || IdxExpr->isValueDependent()
538              || !IdxExpr->isIntegerConstantExpr(ArgNum, S.Context)) {
539            S.Diag(AL.getLoc(), diag::err_ownership_type)
540                << "ownership_returns" << "integer"
541                << IdxExpr->getSourceRange();
542            return;
543          }
544      }
545      break;
546    }
547    default:
548      llvm_unreachable("Unknown ownership attribute");
549    } // switch
550
551    // Check we don't have a conflict with another ownership attribute.
552    for (specific_attr_iterator<OwnershipAttr>
553          i = d->specific_attr_begin<OwnershipAttr>(),
554          e = d->specific_attr_end<OwnershipAttr>();
555        i != e; ++i) {
556      if ((*i)->getOwnKind() != K) {
557        for (const unsigned *I = (*i)->args_begin(), *E = (*i)->args_end();
558             I!=E; ++I) {
559          if (x == *I) {
560            S.Diag(AL.getLoc(), diag::err_attributes_are_not_compatible)
561                << AL.getName()->getName() << "ownership_*";
562          }
563        }
564      }
565    }
566    OwnershipArgs.push_back(x);
567  }
568
569  unsigned* start = OwnershipArgs.data();
570  unsigned size = OwnershipArgs.size();
571  llvm::array_pod_sort(start, start + size);
572
573  if (K != OwnershipAttr::Returns && OwnershipArgs.empty()) {
574    S.Diag(AL.getLoc(), diag::err_attribute_wrong_number_arguments) << 2;
575    return;
576  }
577
578  d->addAttr(::new (S.Context) OwnershipAttr(AL.getLoc(), S.Context, K, Module,
579                                             start, size));
580}
581
582static bool isStaticVarOrStaticFunciton(Decl *D) {
583  if (VarDecl *VD = dyn_cast<VarDecl>(D))
584    return VD->getStorageClass() == SC_Static;
585  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
586    return FD->getStorageClass() == SC_Static;
587  return false;
588}
589
590static void HandleWeakRefAttr(Decl *d, const AttributeList &Attr, Sema &S) {
591  // Check the attribute arguments.
592  if (Attr.getNumArgs() > 1) {
593    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
594    return;
595  }
596
597  // gcc rejects
598  // class c {
599  //   static int a __attribute__((weakref ("v2")));
600  //   static int b() __attribute__((weakref ("f3")));
601  // };
602  // and ignores the attributes of
603  // void f(void) {
604  //   static int a __attribute__((weakref ("v2")));
605  // }
606  // we reject them
607  const DeclContext *Ctx = d->getDeclContext()->getRedeclContext();
608  if (!Ctx->isFileContext()) {
609    S.Diag(Attr.getLoc(), diag::err_attribute_weakref_not_global_context) <<
610        dyn_cast<NamedDecl>(d)->getNameAsString();
611    return;
612  }
613
614  // The GCC manual says
615  //
616  // At present, a declaration to which `weakref' is attached can only
617  // be `static'.
618  //
619  // It also says
620  //
621  // Without a TARGET,
622  // given as an argument to `weakref' or to `alias', `weakref' is
623  // equivalent to `weak'.
624  //
625  // gcc 4.4.1 will accept
626  // int a7 __attribute__((weakref));
627  // as
628  // int a7 __attribute__((weak));
629  // This looks like a bug in gcc. We reject that for now. We should revisit
630  // it if this behaviour is actually used.
631
632  if (!isStaticVarOrStaticFunciton(d)) {
633    S.Diag(Attr.getLoc(), diag::err_attribute_weakref_not_static) <<
634      dyn_cast<NamedDecl>(d)->getNameAsString();
635    return;
636  }
637
638  // GCC rejects
639  // static ((alias ("y"), weakref)).
640  // Should we? How to check that weakref is before or after alias?
641
642  if (Attr.getNumArgs() == 1) {
643    Expr *Arg = Attr.getArg(0);
644    Arg = Arg->IgnoreParenCasts();
645    StringLiteral *Str = dyn_cast<StringLiteral>(Arg);
646
647    if (Str == 0 || Str->isWide()) {
648      S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string)
649          << "weakref" << 1;
650      return;
651    }
652    // GCC will accept anything as the argument of weakref. Should we
653    // check for an existing decl?
654    d->addAttr(::new (S.Context) AliasAttr(Attr.getLoc(), S.Context,
655                                           Str->getString()));
656  }
657
658  d->addAttr(::new (S.Context) WeakRefAttr(Attr.getLoc(), S.Context));
659}
660
661static void HandleAliasAttr(Decl *d, const AttributeList &Attr, Sema &S) {
662  // check the attribute arguments.
663  if (Attr.getNumArgs() != 1) {
664    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
665    return;
666  }
667
668  Expr *Arg = Attr.getArg(0);
669  Arg = Arg->IgnoreParenCasts();
670  StringLiteral *Str = dyn_cast<StringLiteral>(Arg);
671
672  if (Str == 0 || Str->isWide()) {
673    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string)
674      << "alias" << 1;
675    return;
676  }
677
678  // FIXME: check if target symbol exists in current file
679
680  d->addAttr(::new (S.Context) AliasAttr(Attr.getLoc(), S.Context,
681                                         Str->getString()));
682}
683
684static void HandleNakedAttr(Decl *d, const AttributeList &Attr,
685                                   Sema &S) {
686  // Check the attribute arguments.
687  if (Attr.getNumArgs() != 0) {
688    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
689    return;
690  }
691
692  if (!isa<FunctionDecl>(d)) {
693    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
694      << Attr.getName() << 0 /*function*/;
695    return;
696  }
697
698  d->addAttr(::new (S.Context) NakedAttr(Attr.getLoc(), S.Context));
699}
700
701static void HandleAlwaysInlineAttr(Decl *d, const AttributeList &Attr,
702                                   Sema &S) {
703  // Check the attribute arguments.
704  if (Attr.getNumArgs() != 0) {
705    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
706    return;
707  }
708
709  if (!isa<FunctionDecl>(d)) {
710    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
711      << Attr.getName() << 0 /*function*/;
712    return;
713  }
714
715  d->addAttr(::new (S.Context) AlwaysInlineAttr(Attr.getLoc(), S.Context));
716}
717
718static void HandleMallocAttr(Decl *d, const AttributeList &Attr, Sema &S) {
719  // Check the attribute arguments.
720  if (Attr.getNumArgs() != 0) {
721    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
722    return;
723  }
724
725  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(d)) {
726    QualType RetTy = FD->getResultType();
727    if (RetTy->isAnyPointerType() || RetTy->isBlockPointerType()) {
728      d->addAttr(::new (S.Context) MallocAttr(Attr.getLoc(), S.Context));
729      return;
730    }
731  }
732
733  S.Diag(Attr.getLoc(), diag::warn_attribute_malloc_pointer_only);
734}
735
736static void HandleMayAliasAttr(Decl *d, const AttributeList &Attr, Sema &S) {
737  // check the attribute arguments.
738  if (Attr.getNumArgs() != 0) {
739    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
740    return;
741  }
742
743  d->addAttr(::new (S.Context) MayAliasAttr(Attr.getLoc(), S.Context));
744}
745
746static void HandleNoCommonAttr(Decl *d, const AttributeList &Attr, Sema &S) {
747  assert(Attr.isInvalid() == false);
748  if (isa<VarDecl>(d))
749    d->addAttr(::new (S.Context) NoCommonAttr(Attr.getLoc(), S.Context));
750  else
751    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
752      << Attr.getName() << 12 /* variable */;
753}
754
755static void HandleCommonAttr(Decl *d, const AttributeList &Attr, Sema &S) {
756  assert(Attr.isInvalid() == false);
757  if (isa<VarDecl>(d))
758    d->addAttr(::new (S.Context) CommonAttr(Attr.getLoc(), S.Context));
759  else
760    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
761      << Attr.getName() << 12 /* variable */;
762}
763
764static void HandleNoReturnAttr(Decl *d, const AttributeList &Attr, Sema &S) {
765  /* Diagnostics (if any) was emitted by Sema::ProcessFnAttr(). */
766  assert(Attr.isInvalid() == false);
767  d->addAttr(::new (S.Context) NoReturnAttr(Attr.getLoc(), S.Context));
768}
769
770static void HandleAnalyzerNoReturnAttr(Decl *d, const AttributeList &Attr,
771                                       Sema &S) {
772
773  // The checking path for 'noreturn' and 'analyzer_noreturn' are different
774  // because 'analyzer_noreturn' does not impact the type.
775
776  if (Attr.getNumArgs() != 0) {
777    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
778    return;
779  }
780
781  if (!isFunctionOrMethod(d) && !isa<BlockDecl>(d)) {
782    ValueDecl *VD = dyn_cast<ValueDecl>(d);
783    if (VD == 0 || (!VD->getType()->isBlockPointerType()
784                    && !VD->getType()->isFunctionPointerType())) {
785      S.Diag(Attr.getLoc(),
786             Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
787             : diag::warn_attribute_wrong_decl_type)
788      << Attr.getName() << 0 /*function*/;
789      return;
790    }
791  }
792
793  d->addAttr(::new (S.Context) AnalyzerNoReturnAttr(Attr.getLoc(), S.Context));
794}
795
796// PS3 PPU-specific.
797static void HandleVecReturnAttr(Decl *d, const AttributeList &Attr,
798                                       Sema &S) {
799/*
800  Returning a Vector Class in Registers
801
802  According to the PPU ABI specifications, a class with a single member of
803  vector type is returned in memory when used as the return value of a function.
804  This results in inefficient code when implementing vector classes. To return
805  the value in a single vector register, add the vecreturn attribute to the
806  class definition. This attribute is also applicable to struct types.
807
808  Example:
809
810  struct Vector
811  {
812    __vector float xyzw;
813  } __attribute__((vecreturn));
814
815  Vector Add(Vector lhs, Vector rhs)
816  {
817    Vector result;
818    result.xyzw = vec_add(lhs.xyzw, rhs.xyzw);
819    return result; // This will be returned in a register
820  }
821*/
822  if (!isa<RecordDecl>(d)) {
823    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_decl_type)
824      << Attr.getName() << 9 /*class*/;
825    return;
826  }
827
828  if (d->getAttr<VecReturnAttr>()) {
829    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "vecreturn";
830    return;
831  }
832
833  RecordDecl *record = cast<RecordDecl>(d);
834  int count = 0;
835
836  if (!isa<CXXRecordDecl>(record)) {
837    S.Diag(Attr.getLoc(), diag::err_attribute_vecreturn_only_vector_member);
838    return;
839  }
840
841  if (!cast<CXXRecordDecl>(record)->isPOD()) {
842    S.Diag(Attr.getLoc(), diag::err_attribute_vecreturn_only_pod_record);
843    return;
844  }
845
846  for (RecordDecl::field_iterator iter = record->field_begin();
847       iter != record->field_end(); iter++) {
848    if ((count == 1) || !iter->getType()->isVectorType()) {
849      S.Diag(Attr.getLoc(), diag::err_attribute_vecreturn_only_vector_member);
850      return;
851    }
852    count++;
853  }
854
855  d->addAttr(::new (S.Context) VecReturnAttr(Attr.getLoc(), S.Context));
856}
857
858static void HandleDependencyAttr(Decl *d, const AttributeList &Attr, Sema &S) {
859  if (!isFunctionOrMethod(d) && !isa<ParmVarDecl>(d)) {
860    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_decl_type)
861      << Attr.getName() << 8 /*function, method, or parameter*/;
862    return;
863  }
864  // FIXME: Actually store the attribute on the declaration
865}
866
867static void HandleUnusedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
868  // check the attribute arguments.
869  if (Attr.getNumArgs() != 0) {
870    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
871    return;
872  }
873
874  if (!isa<VarDecl>(d) && !isa<ObjCIvarDecl>(d) && !isFunctionOrMethod(d) &&
875      !isa<TypeDecl>(d)) {
876    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
877      << Attr.getName() << 2 /*variable and function*/;
878    return;
879  }
880
881  d->addAttr(::new (S.Context) UnusedAttr(Attr.getLoc(), S.Context));
882}
883
884static void HandleUsedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
885  // check the attribute arguments.
886  if (Attr.getNumArgs() != 0) {
887    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
888    return;
889  }
890
891  if (const VarDecl *VD = dyn_cast<VarDecl>(d)) {
892    if (VD->hasLocalStorage() || VD->hasExternalStorage()) {
893      S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "used";
894      return;
895    }
896  } else if (!isFunctionOrMethod(d)) {
897    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
898      << Attr.getName() << 2 /*variable and function*/;
899    return;
900  }
901
902  d->addAttr(::new (S.Context) UsedAttr(Attr.getLoc(), S.Context));
903}
904
905static void HandleConstructorAttr(Decl *d, const AttributeList &Attr, Sema &S) {
906  // check the attribute arguments.
907  if (Attr.getNumArgs() != 0 && Attr.getNumArgs() != 1) {
908    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments)
909      << "0 or 1";
910    return;
911  }
912
913  int priority = 65535; // FIXME: Do not hardcode such constants.
914  if (Attr.getNumArgs() > 0) {
915    Expr *E = Attr.getArg(0);
916    llvm::APSInt Idx(32);
917    if (E->isTypeDependent() || E->isValueDependent() ||
918        !E->isIntegerConstantExpr(Idx, S.Context)) {
919      S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
920        << "constructor" << 1 << E->getSourceRange();
921      return;
922    }
923    priority = Idx.getZExtValue();
924  }
925
926  if (!isa<FunctionDecl>(d)) {
927    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
928      << Attr.getName() << 0 /*function*/;
929    return;
930  }
931
932  d->addAttr(::new (S.Context) ConstructorAttr(Attr.getLoc(), S.Context,
933                                               priority));
934}
935
936static void HandleDestructorAttr(Decl *d, const AttributeList &Attr, Sema &S) {
937  // check the attribute arguments.
938  if (Attr.getNumArgs() != 0 && Attr.getNumArgs() != 1) {
939    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments)
940       << "0 or 1";
941    return;
942  }
943
944  int priority = 65535; // FIXME: Do not hardcode such constants.
945  if (Attr.getNumArgs() > 0) {
946    Expr *E = Attr.getArg(0);
947    llvm::APSInt Idx(32);
948    if (E->isTypeDependent() || E->isValueDependent() ||
949        !E->isIntegerConstantExpr(Idx, S.Context)) {
950      S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
951        << "destructor" << 1 << E->getSourceRange();
952      return;
953    }
954    priority = Idx.getZExtValue();
955  }
956
957  if (!isa<FunctionDecl>(d)) {
958    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
959      << Attr.getName() << 0 /*function*/;
960    return;
961  }
962
963  d->addAttr(::new (S.Context) DestructorAttr(Attr.getLoc(), S.Context,
964                                              priority));
965}
966
967static void HandleDeprecatedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
968  // check the attribute arguments.
969  int noArgs = Attr.getNumArgs();
970  if (noArgs > 1) {
971    S.Diag(Attr.getLoc(),
972           diag::err_attribute_wrong_number_arguments) << "0 or 1";
973    return;
974  }
975  // Handle the case where deprecated attribute has a text message.
976  StringLiteral *SE;
977  if (noArgs == 1) {
978    Expr *ArgExpr = Attr.getArg(0);
979    SE = dyn_cast<StringLiteral>(ArgExpr);
980    if (!SE) {
981      S.Diag(ArgExpr->getLocStart(),
982             diag::err_attribute_not_string) << "deprecated";
983      return;
984    }
985  }
986  else
987    SE = StringLiteral::CreateEmpty(S.Context, 1);
988
989  d->addAttr(::new (S.Context) DeprecatedAttr(Attr.getLoc(), S.Context,
990                                              SE->getString()));
991}
992
993static void HandleUnavailableAttr(Decl *d, const AttributeList &Attr, Sema &S) {
994  // check the attribute arguments.
995  int noArgs = Attr.getNumArgs();
996  if (noArgs > 1) {
997    S.Diag(Attr.getLoc(),
998           diag::err_attribute_wrong_number_arguments) << "0 or 1";
999    return;
1000  }
1001  // Handle the case where unavailable attribute has a text message.
1002  StringLiteral *SE;
1003  if (noArgs == 1) {
1004    Expr *ArgExpr = Attr.getArg(0);
1005    SE = dyn_cast<StringLiteral>(ArgExpr);
1006    if (!SE) {
1007      S.Diag(ArgExpr->getLocStart(),
1008             diag::err_attribute_not_string) << "unavailable";
1009      return;
1010    }
1011  }
1012  else
1013    SE = StringLiteral::CreateEmpty(S.Context, 1);
1014  d->addAttr(::new (S.Context) UnavailableAttr(Attr.getLoc(), S.Context,
1015                                               SE->getString()));
1016}
1017
1018static void HandleVisibilityAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1019  // check the attribute arguments.
1020  if (Attr.getNumArgs() != 1) {
1021    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1022    return;
1023  }
1024
1025  Expr *Arg = Attr.getArg(0);
1026  Arg = Arg->IgnoreParenCasts();
1027  StringLiteral *Str = dyn_cast<StringLiteral>(Arg);
1028
1029  if (Str == 0 || Str->isWide()) {
1030    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string)
1031      << "visibility" << 1;
1032    return;
1033  }
1034
1035  llvm::StringRef TypeStr = Str->getString();
1036  VisibilityAttr::VisibilityType type;
1037
1038  if (TypeStr == "default")
1039    type = VisibilityAttr::Default;
1040  else if (TypeStr == "hidden")
1041    type = VisibilityAttr::Hidden;
1042  else if (TypeStr == "internal")
1043    type = VisibilityAttr::Hidden; // FIXME
1044  else if (TypeStr == "protected")
1045    type = VisibilityAttr::Protected;
1046  else {
1047    S.Diag(Attr.getLoc(), diag::warn_attribute_unknown_visibility) << TypeStr;
1048    return;
1049  }
1050
1051  d->addAttr(::new (S.Context) VisibilityAttr(Attr.getLoc(), S.Context, type));
1052}
1053
1054static void HandleObjCExceptionAttr(Decl *D, const AttributeList &Attr,
1055                                    Sema &S) {
1056  if (Attr.getNumArgs() != 0) {
1057    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1058    return;
1059  }
1060
1061  ObjCInterfaceDecl *OCI = dyn_cast<ObjCInterfaceDecl>(D);
1062  if (OCI == 0) {
1063    S.Diag(Attr.getLoc(), diag::err_attribute_requires_objc_interface);
1064    return;
1065  }
1066
1067  D->addAttr(::new (S.Context) ObjCExceptionAttr(Attr.getLoc(), S.Context));
1068}
1069
1070static void HandleObjCNSObject(Decl *D, const AttributeList &Attr, Sema &S) {
1071  if (Attr.getNumArgs() != 0) {
1072    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1073    return;
1074  }
1075  if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D)) {
1076    QualType T = TD->getUnderlyingType();
1077    if (!T->isPointerType() ||
1078        !T->getAs<PointerType>()->getPointeeType()->isRecordType()) {
1079      S.Diag(TD->getLocation(), diag::err_nsobject_attribute);
1080      return;
1081    }
1082  }
1083  D->addAttr(::new (S.Context) ObjCNSObjectAttr(Attr.getLoc(), S.Context));
1084}
1085
1086static void
1087HandleOverloadableAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1088  if (Attr.getNumArgs() != 0) {
1089    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1090    return;
1091  }
1092
1093  if (!isa<FunctionDecl>(D)) {
1094    S.Diag(Attr.getLoc(), diag::err_attribute_overloadable_not_function);
1095    return;
1096  }
1097
1098  D->addAttr(::new (S.Context) OverloadableAttr(Attr.getLoc(), S.Context));
1099}
1100
1101static void HandleBlocksAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1102  if (!Attr.getParameterName()) {
1103    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string)
1104      << "blocks" << 1;
1105    return;
1106  }
1107
1108  if (Attr.getNumArgs() != 0) {
1109    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1110    return;
1111  }
1112
1113  BlocksAttr::BlockType type;
1114  if (Attr.getParameterName()->isStr("byref"))
1115    type = BlocksAttr::ByRef;
1116  else {
1117    S.Diag(Attr.getLoc(), diag::warn_attribute_type_not_supported)
1118      << "blocks" << Attr.getParameterName();
1119    return;
1120  }
1121
1122  d->addAttr(::new (S.Context) BlocksAttr(Attr.getLoc(), S.Context, type));
1123}
1124
1125static void HandleSentinelAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1126  // check the attribute arguments.
1127  if (Attr.getNumArgs() > 2) {
1128    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments)
1129      << "0, 1 or 2";
1130    return;
1131  }
1132
1133  int sentinel = 0;
1134  if (Attr.getNumArgs() > 0) {
1135    Expr *E = Attr.getArg(0);
1136    llvm::APSInt Idx(32);
1137    if (E->isTypeDependent() || E->isValueDependent() ||
1138        !E->isIntegerConstantExpr(Idx, S.Context)) {
1139      S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
1140       << "sentinel" << 1 << E->getSourceRange();
1141      return;
1142    }
1143    sentinel = Idx.getZExtValue();
1144
1145    if (sentinel < 0) {
1146      S.Diag(Attr.getLoc(), diag::err_attribute_sentinel_less_than_zero)
1147        << E->getSourceRange();
1148      return;
1149    }
1150  }
1151
1152  int nullPos = 0;
1153  if (Attr.getNumArgs() > 1) {
1154    Expr *E = Attr.getArg(1);
1155    llvm::APSInt Idx(32);
1156    if (E->isTypeDependent() || E->isValueDependent() ||
1157        !E->isIntegerConstantExpr(Idx, S.Context)) {
1158      S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
1159        << "sentinel" << 2 << E->getSourceRange();
1160      return;
1161    }
1162    nullPos = Idx.getZExtValue();
1163
1164    if (nullPos > 1 || nullPos < 0) {
1165      // FIXME: This error message could be improved, it would be nice
1166      // to say what the bounds actually are.
1167      S.Diag(Attr.getLoc(), diag::err_attribute_sentinel_not_zero_or_one)
1168        << E->getSourceRange();
1169      return;
1170    }
1171  }
1172
1173  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(d)) {
1174    const FunctionType *FT = FD->getType()->getAs<FunctionType>();
1175    assert(FT && "FunctionDecl has non-function type?");
1176
1177    if (isa<FunctionNoProtoType>(FT)) {
1178      S.Diag(Attr.getLoc(), diag::warn_attribute_sentinel_named_arguments);
1179      return;
1180    }
1181
1182    if (!cast<FunctionProtoType>(FT)->isVariadic()) {
1183      S.Diag(Attr.getLoc(), diag::warn_attribute_sentinel_not_variadic) << 0;
1184      return;
1185    }
1186  } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(d)) {
1187    if (!MD->isVariadic()) {
1188      S.Diag(Attr.getLoc(), diag::warn_attribute_sentinel_not_variadic) << 0;
1189      return;
1190    }
1191  } else if (isa<BlockDecl>(d)) {
1192    // Note! BlockDecl is typeless. Variadic diagnostics will be issued by the
1193    // caller.
1194    ;
1195  } else if (const VarDecl *V = dyn_cast<VarDecl>(d)) {
1196    QualType Ty = V->getType();
1197    if (Ty->isBlockPointerType() || Ty->isFunctionPointerType()) {
1198      const FunctionType *FT = Ty->isFunctionPointerType() ? getFunctionType(d)
1199       : Ty->getAs<BlockPointerType>()->getPointeeType()->getAs<FunctionType>();
1200      if (!cast<FunctionProtoType>(FT)->isVariadic()) {
1201        int m = Ty->isFunctionPointerType() ? 0 : 1;
1202        S.Diag(Attr.getLoc(), diag::warn_attribute_sentinel_not_variadic) << m;
1203        return;
1204      }
1205    } else {
1206      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1207      << Attr.getName() << 6 /*function, method or block */;
1208      return;
1209    }
1210  } else {
1211    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1212      << Attr.getName() << 6 /*function, method or block */;
1213    return;
1214  }
1215  d->addAttr(::new (S.Context) SentinelAttr(Attr.getLoc(), S.Context, sentinel,
1216                                            nullPos));
1217}
1218
1219static void HandleWarnUnusedResult(Decl *D, const AttributeList &Attr, Sema &S) {
1220  // check the attribute arguments.
1221  if (Attr.getNumArgs() != 0) {
1222    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1223    return;
1224  }
1225
1226  if (!isFunction(D) && !isa<ObjCMethodDecl>(D)) {
1227    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1228      << Attr.getName() << 0 /*function*/;
1229    return;
1230  }
1231
1232  if (isFunction(D) && getFunctionType(D)->getResultType()->isVoidType()) {
1233    S.Diag(Attr.getLoc(), diag::warn_attribute_void_function_method)
1234      << Attr.getName() << 0;
1235    return;
1236  }
1237  if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
1238    if (MD->getResultType()->isVoidType()) {
1239      S.Diag(Attr.getLoc(), diag::warn_attribute_void_function_method)
1240      << Attr.getName() << 1;
1241      return;
1242    }
1243
1244  D->addAttr(::new (S.Context) WarnUnusedResultAttr(Attr.getLoc(), S.Context));
1245}
1246
1247static void HandleWeakAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1248  // check the attribute arguments.
1249  if (Attr.getNumArgs() != 0) {
1250    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1251    return;
1252  }
1253
1254  /* weak only applies to non-static declarations */
1255  if (isStaticVarOrStaticFunciton(D)) {
1256    S.Diag(Attr.getLoc(), diag::err_attribute_weak_static) <<
1257      dyn_cast<NamedDecl>(D)->getNameAsString();
1258    return;
1259  }
1260
1261  // TODO: could also be applied to methods?
1262  if (!isa<FunctionDecl>(D) && !isa<VarDecl>(D)) {
1263    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1264      << Attr.getName() << 2 /*variable and function*/;
1265    return;
1266  }
1267
1268  D->addAttr(::new (S.Context) WeakAttr(Attr.getLoc(), S.Context));
1269}
1270
1271static void HandleWeakImportAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1272  // check the attribute arguments.
1273  if (Attr.getNumArgs() != 0) {
1274    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1275    return;
1276  }
1277
1278  // weak_import only applies to variable & function declarations.
1279  bool isDef = false;
1280  if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
1281    isDef = (!VD->hasExternalStorage() || VD->getInit());
1282  } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1283    isDef = FD->hasBody();
1284  } else if (isa<ObjCPropertyDecl>(D) || isa<ObjCMethodDecl>(D)) {
1285    // We ignore weak import on properties and methods
1286    return;
1287  } else if (!(S.LangOpts.ObjCNonFragileABI && isa<ObjCInterfaceDecl>(D))) {
1288    // Don't issue the warning for darwin as target; yet, ignore the attribute.
1289    if (S.Context.Target.getTriple().getOS() != llvm::Triple::Darwin ||
1290        !isa<ObjCInterfaceDecl>(D))
1291      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1292        << Attr.getName() << 2 /*variable and function*/;
1293      return;
1294  }
1295
1296  // Merge should handle any subsequent violations.
1297  if (isDef) {
1298    S.Diag(Attr.getLoc(),
1299           diag::warn_attribute_weak_import_invalid_on_definition)
1300      << "weak_import" << 2 /*variable and function*/;
1301    return;
1302  }
1303
1304  D->addAttr(::new (S.Context) WeakImportAttr(Attr.getLoc(), S.Context));
1305}
1306
1307static void HandleReqdWorkGroupSize(Decl *D, const AttributeList &Attr,
1308                                    Sema &S) {
1309  // Attribute has 3 arguments.
1310  if (Attr.getNumArgs() != 3) {
1311    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1312    return;
1313  }
1314
1315  unsigned WGSize[3];
1316  for (unsigned i = 0; i < 3; ++i) {
1317    Expr *E = Attr.getArg(i);
1318    llvm::APSInt ArgNum(32);
1319    if (E->isTypeDependent() || E->isValueDependent() ||
1320        !E->isIntegerConstantExpr(ArgNum, S.Context)) {
1321      S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
1322        << "reqd_work_group_size" << E->getSourceRange();
1323      return;
1324    }
1325    WGSize[i] = (unsigned) ArgNum.getZExtValue();
1326  }
1327  D->addAttr(::new (S.Context) ReqdWorkGroupSizeAttr(Attr.getLoc(), S.Context,
1328                                                     WGSize[0], WGSize[1],
1329                                                     WGSize[2]));
1330}
1331
1332static void HandleSectionAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1333  // Attribute has no arguments.
1334  if (Attr.getNumArgs() != 1) {
1335    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1336    return;
1337  }
1338
1339  // Make sure that there is a string literal as the sections's single
1340  // argument.
1341  Expr *ArgExpr = Attr.getArg(0);
1342  StringLiteral *SE = dyn_cast<StringLiteral>(ArgExpr);
1343  if (!SE) {
1344    S.Diag(ArgExpr->getLocStart(), diag::err_attribute_not_string) << "section";
1345    return;
1346  }
1347
1348  // If the target wants to validate the section specifier, make it happen.
1349  std::string Error = S.Context.Target.isValidSectionSpecifier(SE->getString());
1350  if (!Error.empty()) {
1351    S.Diag(SE->getLocStart(), diag::err_attribute_section_invalid_for_target)
1352    << Error;
1353    return;
1354  }
1355
1356  // This attribute cannot be applied to local variables.
1357  if (isa<VarDecl>(D) && cast<VarDecl>(D)->hasLocalStorage()) {
1358    S.Diag(SE->getLocStart(), diag::err_attribute_section_local_variable);
1359    return;
1360  }
1361
1362  D->addAttr(::new (S.Context) SectionAttr(Attr.getLoc(), S.Context,
1363                                           SE->getString()));
1364}
1365
1366
1367static void HandleNothrowAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1368  // check the attribute arguments.
1369  if (Attr.getNumArgs() != 0) {
1370    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1371    return;
1372  }
1373
1374  d->addAttr(::new (S.Context) NoThrowAttr(Attr.getLoc(), S.Context));
1375}
1376
1377static void HandleConstAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1378  // check the attribute arguments.
1379  if (Attr.getNumArgs() != 0) {
1380    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1381    return;
1382  }
1383
1384  d->addAttr(::new (S.Context) ConstAttr(Attr.getLoc(), S.Context));
1385}
1386
1387static void HandlePureAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1388  // check the attribute arguments.
1389  if (Attr.getNumArgs() != 0) {
1390    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1391    return;
1392  }
1393
1394  d->addAttr(::new (S.Context) PureAttr(Attr.getLoc(), S.Context));
1395}
1396
1397static void HandleCleanupAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1398  if (!Attr.getParameterName()) {
1399    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1400    return;
1401  }
1402
1403  if (Attr.getNumArgs() != 0) {
1404    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1405    return;
1406  }
1407
1408  VarDecl *VD = dyn_cast<VarDecl>(d);
1409
1410  if (!VD || !VD->hasLocalStorage()) {
1411    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "cleanup";
1412    return;
1413  }
1414
1415  // Look up the function
1416  // FIXME: Lookup probably isn't looking in the right place
1417  NamedDecl *CleanupDecl
1418    = S.LookupSingleName(S.TUScope, Attr.getParameterName(),
1419                         Attr.getParameterLoc(), Sema::LookupOrdinaryName);
1420  if (!CleanupDecl) {
1421    S.Diag(Attr.getParameterLoc(), diag::err_attribute_cleanup_arg_not_found) <<
1422      Attr.getParameterName();
1423    return;
1424  }
1425
1426  FunctionDecl *FD = dyn_cast<FunctionDecl>(CleanupDecl);
1427  if (!FD) {
1428    S.Diag(Attr.getParameterLoc(),
1429           diag::err_attribute_cleanup_arg_not_function)
1430      << Attr.getParameterName();
1431    return;
1432  }
1433
1434  if (FD->getNumParams() != 1) {
1435    S.Diag(Attr.getParameterLoc(),
1436           diag::err_attribute_cleanup_func_must_take_one_arg)
1437      << Attr.getParameterName();
1438    return;
1439  }
1440
1441  // We're currently more strict than GCC about what function types we accept.
1442  // If this ever proves to be a problem it should be easy to fix.
1443  QualType Ty = S.Context.getPointerType(VD->getType());
1444  QualType ParamTy = FD->getParamDecl(0)->getType();
1445  if (S.CheckAssignmentConstraints(ParamTy, Ty) != Sema::Compatible) {
1446    S.Diag(Attr.getParameterLoc(),
1447           diag::err_attribute_cleanup_func_arg_incompatible_type) <<
1448      Attr.getParameterName() << ParamTy << Ty;
1449    return;
1450  }
1451
1452  d->addAttr(::new (S.Context) CleanupAttr(Attr.getLoc(), S.Context, FD));
1453  S.MarkDeclarationReferenced(Attr.getParameterLoc(), FD);
1454}
1455
1456/// Handle __attribute__((format_arg((idx)))) attribute based on
1457/// http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
1458static void HandleFormatArgAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1459  if (Attr.getNumArgs() != 1) {
1460    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1461    return;
1462  }
1463  if (!isFunctionOrMethod(d) || !hasFunctionProto(d)) {
1464    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1465    << Attr.getName() << 0 /*function*/;
1466    return;
1467  }
1468
1469  // In C++ the implicit 'this' function parameter also counts, and they are
1470  // counted from one.
1471  bool HasImplicitThisParam = isInstanceMethod(d);
1472  unsigned NumArgs  = getFunctionOrMethodNumArgs(d) + HasImplicitThisParam;
1473  unsigned FirstIdx = 1;
1474
1475  // checks for the 2nd argument
1476  Expr *IdxExpr = Attr.getArg(0);
1477  llvm::APSInt Idx(32);
1478  if (IdxExpr->isTypeDependent() || IdxExpr->isValueDependent() ||
1479      !IdxExpr->isIntegerConstantExpr(Idx, S.Context)) {
1480    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
1481    << "format" << 2 << IdxExpr->getSourceRange();
1482    return;
1483  }
1484
1485  if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) {
1486    S.Diag(Attr.getLoc(), diag::err_attribute_argument_out_of_bounds)
1487    << "format" << 2 << IdxExpr->getSourceRange();
1488    return;
1489  }
1490
1491  unsigned ArgIdx = Idx.getZExtValue() - 1;
1492
1493  if (HasImplicitThisParam) {
1494    if (ArgIdx == 0) {
1495      S.Diag(Attr.getLoc(), diag::err_attribute_invalid_implicit_this_argument)
1496        << "format_arg" << IdxExpr->getSourceRange();
1497      return;
1498    }
1499    ArgIdx--;
1500  }
1501
1502  // make sure the format string is really a string
1503  QualType Ty = getFunctionOrMethodArgType(d, ArgIdx);
1504
1505  bool not_nsstring_type = !isNSStringType(Ty, S.Context);
1506  if (not_nsstring_type &&
1507      !isCFStringType(Ty, S.Context) &&
1508      (!Ty->isPointerType() ||
1509       !Ty->getAs<PointerType>()->getPointeeType()->isCharType())) {
1510    // FIXME: Should highlight the actual expression that has the wrong type.
1511    S.Diag(Attr.getLoc(), diag::err_format_attribute_not)
1512    << (not_nsstring_type ? "a string type" : "an NSString")
1513       << IdxExpr->getSourceRange();
1514    return;
1515  }
1516  Ty = getFunctionOrMethodResultType(d);
1517  if (!isNSStringType(Ty, S.Context) &&
1518      !isCFStringType(Ty, S.Context) &&
1519      (!Ty->isPointerType() ||
1520       !Ty->getAs<PointerType>()->getPointeeType()->isCharType())) {
1521    // FIXME: Should highlight the actual expression that has the wrong type.
1522    S.Diag(Attr.getLoc(), diag::err_format_attribute_result_not)
1523    << (not_nsstring_type ? "string type" : "NSString")
1524       << IdxExpr->getSourceRange();
1525    return;
1526  }
1527
1528  d->addAttr(::new (S.Context) FormatArgAttr(Attr.getLoc(), S.Context,
1529                                             Idx.getZExtValue()));
1530}
1531
1532enum FormatAttrKind {
1533  CFStringFormat,
1534  NSStringFormat,
1535  StrftimeFormat,
1536  SupportedFormat,
1537  IgnoredFormat,
1538  InvalidFormat
1539};
1540
1541/// getFormatAttrKind - Map from format attribute names to supported format
1542/// types.
1543static FormatAttrKind getFormatAttrKind(llvm::StringRef Format) {
1544  // Check for formats that get handled specially.
1545  if (Format == "NSString")
1546    return NSStringFormat;
1547  if (Format == "CFString")
1548    return CFStringFormat;
1549  if (Format == "strftime")
1550    return StrftimeFormat;
1551
1552  // Otherwise, check for supported formats.
1553  if (Format == "scanf" || Format == "printf" || Format == "printf0" ||
1554      Format == "strfmon" || Format == "cmn_err" || Format == "strftime" ||
1555      Format == "NSString" || Format == "CFString" || Format == "vcmn_err" ||
1556      Format == "zcmn_err")
1557    return SupportedFormat;
1558
1559  if (Format == "gcc_diag" || Format == "gcc_cdiag" ||
1560      Format == "gcc_cxxdiag" || Format == "gcc_tdiag")
1561    return IgnoredFormat;
1562
1563  return InvalidFormat;
1564}
1565
1566/// Handle __attribute__((init_priority(priority))) attributes based on
1567/// http://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Attributes.html
1568static void HandleInitPriorityAttr(Decl *d, const AttributeList &Attr,
1569                                   Sema &S) {
1570  if (!S.getLangOptions().CPlusPlus) {
1571    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
1572    return;
1573  }
1574
1575  if (!isa<VarDecl>(d) || S.getCurFunctionOrMethodDecl()) {
1576    S.Diag(Attr.getLoc(), diag::err_init_priority_object_attr);
1577    Attr.setInvalid();
1578    return;
1579  }
1580  QualType T = dyn_cast<VarDecl>(d)->getType();
1581  if (S.Context.getAsArrayType(T))
1582    T = S.Context.getBaseElementType(T);
1583  if (!T->getAs<RecordType>()) {
1584    S.Diag(Attr.getLoc(), diag::err_init_priority_object_attr);
1585    Attr.setInvalid();
1586    return;
1587  }
1588
1589  if (Attr.getNumArgs() != 1) {
1590    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1591    Attr.setInvalid();
1592    return;
1593  }
1594  Expr *priorityExpr = Attr.getArg(0);
1595
1596  llvm::APSInt priority(32);
1597  if (priorityExpr->isTypeDependent() || priorityExpr->isValueDependent() ||
1598      !priorityExpr->isIntegerConstantExpr(priority, S.Context)) {
1599    S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
1600    << "init_priority" << priorityExpr->getSourceRange();
1601    Attr.setInvalid();
1602    return;
1603  }
1604  unsigned prioritynum = priority.getZExtValue();
1605  if (prioritynum < 101 || prioritynum > 65535) {
1606    S.Diag(Attr.getLoc(), diag::err_attribute_argument_outof_range)
1607    <<  priorityExpr->getSourceRange();
1608    Attr.setInvalid();
1609    return;
1610  }
1611  d->addAttr(::new (S.Context) InitPriorityAttr(Attr.getLoc(), S.Context,
1612                                                prioritynum));
1613}
1614
1615/// Handle __attribute__((format(type,idx,firstarg))) attributes based on
1616/// http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html
1617static void HandleFormatAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1618
1619  if (!Attr.getParameterName()) {
1620    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_string)
1621      << "format" << 1;
1622    return;
1623  }
1624
1625  if (Attr.getNumArgs() != 2) {
1626    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 3;
1627    return;
1628  }
1629
1630  if (!isFunctionOrMethodOrBlock(d) || !hasFunctionProto(d)) {
1631    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1632      << Attr.getName() << 0 /*function*/;
1633    return;
1634  }
1635
1636  // In C++ the implicit 'this' function parameter also counts, and they are
1637  // counted from one.
1638  bool HasImplicitThisParam = isInstanceMethod(d);
1639  unsigned NumArgs  = getFunctionOrMethodNumArgs(d) + HasImplicitThisParam;
1640  unsigned FirstIdx = 1;
1641
1642  llvm::StringRef Format = Attr.getParameterName()->getName();
1643
1644  // Normalize the argument, __foo__ becomes foo.
1645  if (Format.startswith("__") && Format.endswith("__"))
1646    Format = Format.substr(2, Format.size() - 4);
1647
1648  // Check for supported formats.
1649  FormatAttrKind Kind = getFormatAttrKind(Format);
1650
1651  if (Kind == IgnoredFormat)
1652    return;
1653
1654  if (Kind == InvalidFormat) {
1655    S.Diag(Attr.getLoc(), diag::warn_attribute_type_not_supported)
1656      << "format" << Attr.getParameterName()->getName();
1657    return;
1658  }
1659
1660  // checks for the 2nd argument
1661  Expr *IdxExpr = Attr.getArg(0);
1662  llvm::APSInt Idx(32);
1663  if (IdxExpr->isTypeDependent() || IdxExpr->isValueDependent() ||
1664      !IdxExpr->isIntegerConstantExpr(Idx, S.Context)) {
1665    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
1666      << "format" << 2 << IdxExpr->getSourceRange();
1667    return;
1668  }
1669
1670  if (Idx.getZExtValue() < FirstIdx || Idx.getZExtValue() > NumArgs) {
1671    S.Diag(Attr.getLoc(), diag::err_attribute_argument_out_of_bounds)
1672      << "format" << 2 << IdxExpr->getSourceRange();
1673    return;
1674  }
1675
1676  // FIXME: Do we need to bounds check?
1677  unsigned ArgIdx = Idx.getZExtValue() - 1;
1678
1679  if (HasImplicitThisParam) {
1680    if (ArgIdx == 0) {
1681      S.Diag(Attr.getLoc(),
1682             diag::err_format_attribute_implicit_this_format_string)
1683        << IdxExpr->getSourceRange();
1684      return;
1685    }
1686    ArgIdx--;
1687  }
1688
1689  // make sure the format string is really a string
1690  QualType Ty = getFunctionOrMethodArgType(d, ArgIdx);
1691
1692  if (Kind == CFStringFormat) {
1693    if (!isCFStringType(Ty, S.Context)) {
1694      S.Diag(Attr.getLoc(), diag::err_format_attribute_not)
1695        << "a CFString" << IdxExpr->getSourceRange();
1696      return;
1697    }
1698  } else if (Kind == NSStringFormat) {
1699    // FIXME: do we need to check if the type is NSString*?  What are the
1700    // semantics?
1701    if (!isNSStringType(Ty, S.Context)) {
1702      // FIXME: Should highlight the actual expression that has the wrong type.
1703      S.Diag(Attr.getLoc(), diag::err_format_attribute_not)
1704        << "an NSString" << IdxExpr->getSourceRange();
1705      return;
1706    }
1707  } else if (!Ty->isPointerType() ||
1708             !Ty->getAs<PointerType>()->getPointeeType()->isCharType()) {
1709    // FIXME: Should highlight the actual expression that has the wrong type.
1710    S.Diag(Attr.getLoc(), diag::err_format_attribute_not)
1711      << "a string type" << IdxExpr->getSourceRange();
1712    return;
1713  }
1714
1715  // check the 3rd argument
1716  Expr *FirstArgExpr = Attr.getArg(1);
1717  llvm::APSInt FirstArg(32);
1718  if (FirstArgExpr->isTypeDependent() || FirstArgExpr->isValueDependent() ||
1719      !FirstArgExpr->isIntegerConstantExpr(FirstArg, S.Context)) {
1720    S.Diag(Attr.getLoc(), diag::err_attribute_argument_n_not_int)
1721      << "format" << 3 << FirstArgExpr->getSourceRange();
1722    return;
1723  }
1724
1725  // check if the function is variadic if the 3rd argument non-zero
1726  if (FirstArg != 0) {
1727    if (isFunctionOrMethodVariadic(d)) {
1728      ++NumArgs; // +1 for ...
1729    } else {
1730      S.Diag(d->getLocation(), diag::err_format_attribute_requires_variadic);
1731      return;
1732    }
1733  }
1734
1735  // strftime requires FirstArg to be 0 because it doesn't read from any
1736  // variable the input is just the current time + the format string.
1737  if (Kind == StrftimeFormat) {
1738    if (FirstArg != 0) {
1739      S.Diag(Attr.getLoc(), diag::err_format_strftime_third_parameter)
1740        << FirstArgExpr->getSourceRange();
1741      return;
1742    }
1743  // if 0 it disables parameter checking (to use with e.g. va_list)
1744  } else if (FirstArg != 0 && FirstArg != NumArgs) {
1745    S.Diag(Attr.getLoc(), diag::err_attribute_argument_out_of_bounds)
1746      << "format" << 3 << FirstArgExpr->getSourceRange();
1747    return;
1748  }
1749
1750  d->addAttr(::new (S.Context) FormatAttr(Attr.getLoc(), S.Context, Format,
1751                                          Idx.getZExtValue(),
1752                                          FirstArg.getZExtValue()));
1753}
1754
1755static void HandleTransparentUnionAttr(Decl *d, const AttributeList &Attr,
1756                                       Sema &S) {
1757  // check the attribute arguments.
1758  if (Attr.getNumArgs() != 0) {
1759    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1760    return;
1761  }
1762
1763  // Try to find the underlying union declaration.
1764  RecordDecl *RD = 0;
1765  TypedefDecl *TD = dyn_cast<TypedefDecl>(d);
1766  if (TD && TD->getUnderlyingType()->isUnionType())
1767    RD = TD->getUnderlyingType()->getAsUnionType()->getDecl();
1768  else
1769    RD = dyn_cast<RecordDecl>(d);
1770
1771  if (!RD || !RD->isUnion()) {
1772    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
1773      << Attr.getName() << 1 /*union*/;
1774    return;
1775  }
1776
1777  if (!RD->isDefinition()) {
1778    S.Diag(Attr.getLoc(),
1779        diag::warn_transparent_union_attribute_not_definition);
1780    return;
1781  }
1782
1783  RecordDecl::field_iterator Field = RD->field_begin(),
1784                          FieldEnd = RD->field_end();
1785  if (Field == FieldEnd) {
1786    S.Diag(Attr.getLoc(), diag::warn_transparent_union_attribute_zero_fields);
1787    return;
1788  }
1789
1790  FieldDecl *FirstField = *Field;
1791  QualType FirstType = FirstField->getType();
1792  if (FirstType->hasFloatingRepresentation() || FirstType->isVectorType()) {
1793    S.Diag(FirstField->getLocation(),
1794           diag::warn_transparent_union_attribute_floating)
1795      << FirstType->isVectorType() << FirstType;
1796    return;
1797  }
1798
1799  uint64_t FirstSize = S.Context.getTypeSize(FirstType);
1800  uint64_t FirstAlign = S.Context.getTypeAlign(FirstType);
1801  for (; Field != FieldEnd; ++Field) {
1802    QualType FieldType = Field->getType();
1803    if (S.Context.getTypeSize(FieldType) != FirstSize ||
1804        S.Context.getTypeAlign(FieldType) != FirstAlign) {
1805      // Warn if we drop the attribute.
1806      bool isSize = S.Context.getTypeSize(FieldType) != FirstSize;
1807      unsigned FieldBits = isSize? S.Context.getTypeSize(FieldType)
1808                                 : S.Context.getTypeAlign(FieldType);
1809      S.Diag(Field->getLocation(),
1810          diag::warn_transparent_union_attribute_field_size_align)
1811        << isSize << Field->getDeclName() << FieldBits;
1812      unsigned FirstBits = isSize? FirstSize : FirstAlign;
1813      S.Diag(FirstField->getLocation(),
1814             diag::note_transparent_union_first_field_size_align)
1815        << isSize << FirstBits;
1816      return;
1817    }
1818  }
1819
1820  RD->addAttr(::new (S.Context) TransparentUnionAttr(Attr.getLoc(), S.Context));
1821}
1822
1823static void HandleAnnotateAttr(Decl *d, const AttributeList &Attr, Sema &S) {
1824  // check the attribute arguments.
1825  if (Attr.getNumArgs() != 1) {
1826    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1827    return;
1828  }
1829  Expr *ArgExpr = Attr.getArg(0);
1830  StringLiteral *SE = dyn_cast<StringLiteral>(ArgExpr);
1831
1832  // Make sure that there is a string literal as the annotation's single
1833  // argument.
1834  if (!SE) {
1835    S.Diag(ArgExpr->getLocStart(), diag::err_attribute_not_string) <<"annotate";
1836    return;
1837  }
1838  d->addAttr(::new (S.Context) AnnotateAttr(Attr.getLoc(), S.Context,
1839                                            SE->getString()));
1840}
1841
1842static void HandleAlignedAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1843  // check the attribute arguments.
1844  if (Attr.getNumArgs() > 1) {
1845    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
1846    return;
1847  }
1848
1849  //FIXME: The C++0x version of this attribute has more limited applicabilty
1850  //       than GNU's, and should error out when it is used to specify a
1851  //       weaker alignment, rather than being silently ignored.
1852
1853  if (Attr.getNumArgs() == 0) {
1854    D->addAttr(::new (S.Context) AlignedAttr(Attr.getLoc(), S.Context, true, 0));
1855    return;
1856  }
1857
1858  S.AddAlignedAttr(Attr.getLoc(), D, Attr.getArg(0));
1859}
1860
1861void Sema::AddAlignedAttr(SourceLocation AttrLoc, Decl *D, Expr *E) {
1862  if (E->isTypeDependent() || E->isValueDependent()) {
1863    // Save dependent expressions in the AST to be instantiated.
1864    D->addAttr(::new (Context) AlignedAttr(AttrLoc, Context, true, E));
1865    return;
1866  }
1867
1868  // FIXME: Cache the number on the Attr object?
1869  llvm::APSInt Alignment(32);
1870  if (!E->isIntegerConstantExpr(Alignment, Context)) {
1871    Diag(AttrLoc, diag::err_attribute_argument_not_int)
1872      << "aligned" << E->getSourceRange();
1873    return;
1874  }
1875  if (!llvm::isPowerOf2_64(Alignment.getZExtValue())) {
1876    Diag(AttrLoc, diag::err_attribute_aligned_not_power_of_two)
1877      << E->getSourceRange();
1878    return;
1879  }
1880
1881  D->addAttr(::new (Context) AlignedAttr(AttrLoc, Context, true, E));
1882}
1883
1884void Sema::AddAlignedAttr(SourceLocation AttrLoc, Decl *D, TypeSourceInfo *TS) {
1885  // FIXME: Cache the number on the Attr object if non-dependent?
1886  // FIXME: Perform checking of type validity
1887  D->addAttr(::new (Context) AlignedAttr(AttrLoc, Context, false, TS));
1888  return;
1889}
1890
1891/// HandleModeAttr - This attribute modifies the width of a decl with primitive
1892/// type.
1893///
1894/// Despite what would be logical, the mode attribute is a decl attribute, not a
1895/// type attribute: 'int ** __attribute((mode(HI))) *G;' tries to make 'G' be
1896/// HImode, not an intermediate pointer.
1897static void HandleModeAttr(Decl *D, const AttributeList &Attr, Sema &S) {
1898  // This attribute isn't documented, but glibc uses it.  It changes
1899  // the width of an int or unsigned int to the specified size.
1900
1901  // Check that there aren't any arguments
1902  if (Attr.getNumArgs() != 0) {
1903    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
1904    return;
1905  }
1906
1907  IdentifierInfo *Name = Attr.getParameterName();
1908  if (!Name) {
1909    S.Diag(Attr.getLoc(), diag::err_attribute_missing_parameter_name);
1910    return;
1911  }
1912
1913  llvm::StringRef Str = Attr.getParameterName()->getName();
1914
1915  // Normalize the attribute name, __foo__ becomes foo.
1916  if (Str.startswith("__") && Str.endswith("__"))
1917    Str = Str.substr(2, Str.size() - 4);
1918
1919  unsigned DestWidth = 0;
1920  bool IntegerMode = true;
1921  bool ComplexMode = false;
1922  switch (Str.size()) {
1923  case 2:
1924    switch (Str[0]) {
1925    case 'Q': DestWidth = 8; break;
1926    case 'H': DestWidth = 16; break;
1927    case 'S': DestWidth = 32; break;
1928    case 'D': DestWidth = 64; break;
1929    case 'X': DestWidth = 96; break;
1930    case 'T': DestWidth = 128; break;
1931    }
1932    if (Str[1] == 'F') {
1933      IntegerMode = false;
1934    } else if (Str[1] == 'C') {
1935      IntegerMode = false;
1936      ComplexMode = true;
1937    } else if (Str[1] != 'I') {
1938      DestWidth = 0;
1939    }
1940    break;
1941  case 4:
1942    // FIXME: glibc uses 'word' to define register_t; this is narrower than a
1943    // pointer on PIC16 and other embedded platforms.
1944    if (Str == "word")
1945      DestWidth = S.Context.Target.getPointerWidth(0);
1946    else if (Str == "byte")
1947      DestWidth = S.Context.Target.getCharWidth();
1948    break;
1949  case 7:
1950    if (Str == "pointer")
1951      DestWidth = S.Context.Target.getPointerWidth(0);
1952    break;
1953  }
1954
1955  QualType OldTy;
1956  if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D))
1957    OldTy = TD->getUnderlyingType();
1958  else if (ValueDecl *VD = dyn_cast<ValueDecl>(D))
1959    OldTy = VD->getType();
1960  else {
1961    S.Diag(D->getLocation(), diag::err_attr_wrong_decl)
1962      << "mode" << SourceRange(Attr.getLoc(), Attr.getLoc());
1963    return;
1964  }
1965
1966  if (!OldTy->getAs<BuiltinType>() && !OldTy->isComplexType())
1967    S.Diag(Attr.getLoc(), diag::err_mode_not_primitive);
1968  else if (IntegerMode) {
1969    if (!OldTy->isIntegralOrEnumerationType())
1970      S.Diag(Attr.getLoc(), diag::err_mode_wrong_type);
1971  } else if (ComplexMode) {
1972    if (!OldTy->isComplexType())
1973      S.Diag(Attr.getLoc(), diag::err_mode_wrong_type);
1974  } else {
1975    if (!OldTy->isFloatingType())
1976      S.Diag(Attr.getLoc(), diag::err_mode_wrong_type);
1977  }
1978
1979  // FIXME: Sync this with InitializePredefinedMacros; we need to match int8_t
1980  // and friends, at least with glibc.
1981  // FIXME: Make sure 32/64-bit integers don't get defined to types of the wrong
1982  // width on unusual platforms.
1983  // FIXME: Make sure floating-point mappings are accurate
1984  // FIXME: Support XF and TF types
1985  QualType NewTy;
1986  switch (DestWidth) {
1987  case 0:
1988    S.Diag(Attr.getLoc(), diag::err_unknown_machine_mode) << Name;
1989    return;
1990  default:
1991    S.Diag(Attr.getLoc(), diag::err_unsupported_machine_mode) << Name;
1992    return;
1993  case 8:
1994    if (!IntegerMode) {
1995      S.Diag(Attr.getLoc(), diag::err_unsupported_machine_mode) << Name;
1996      return;
1997    }
1998    if (OldTy->isSignedIntegerType())
1999      NewTy = S.Context.SignedCharTy;
2000    else
2001      NewTy = S.Context.UnsignedCharTy;
2002    break;
2003  case 16:
2004    if (!IntegerMode) {
2005      S.Diag(Attr.getLoc(), diag::err_unsupported_machine_mode) << Name;
2006      return;
2007    }
2008    if (OldTy->isSignedIntegerType())
2009      NewTy = S.Context.ShortTy;
2010    else
2011      NewTy = S.Context.UnsignedShortTy;
2012    break;
2013  case 32:
2014    if (!IntegerMode)
2015      NewTy = S.Context.FloatTy;
2016    else if (OldTy->isSignedIntegerType())
2017      NewTy = S.Context.IntTy;
2018    else
2019      NewTy = S.Context.UnsignedIntTy;
2020    break;
2021  case 64:
2022    if (!IntegerMode)
2023      NewTy = S.Context.DoubleTy;
2024    else if (OldTy->isSignedIntegerType())
2025      if (S.Context.Target.getLongWidth() == 64)
2026        NewTy = S.Context.LongTy;
2027      else
2028        NewTy = S.Context.LongLongTy;
2029    else
2030      if (S.Context.Target.getLongWidth() == 64)
2031        NewTy = S.Context.UnsignedLongTy;
2032      else
2033        NewTy = S.Context.UnsignedLongLongTy;
2034    break;
2035  case 96:
2036    NewTy = S.Context.LongDoubleTy;
2037    break;
2038  case 128:
2039    if (!IntegerMode) {
2040      S.Diag(Attr.getLoc(), diag::err_unsupported_machine_mode) << Name;
2041      return;
2042    }
2043    if (OldTy->isSignedIntegerType())
2044      NewTy = S.Context.Int128Ty;
2045    else
2046      NewTy = S.Context.UnsignedInt128Ty;
2047    break;
2048  }
2049
2050  if (ComplexMode) {
2051    NewTy = S.Context.getComplexType(NewTy);
2052  }
2053
2054  // Install the new type.
2055  if (TypedefDecl *TD = dyn_cast<TypedefDecl>(D)) {
2056    // FIXME: preserve existing source info.
2057    TD->setTypeSourceInfo(S.Context.getTrivialTypeSourceInfo(NewTy));
2058  } else
2059    cast<ValueDecl>(D)->setType(NewTy);
2060}
2061
2062static void HandleNoDebugAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2063  // check the attribute arguments.
2064  if (Attr.getNumArgs() > 0) {
2065    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2066    return;
2067  }
2068
2069  if (!isFunctionOrMethod(d)) {
2070    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2071      << Attr.getName() << 0 /*function*/;
2072    return;
2073  }
2074
2075  d->addAttr(::new (S.Context) NoDebugAttr(Attr.getLoc(), S.Context));
2076}
2077
2078static void HandleNoInlineAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2079  // check the attribute arguments.
2080  if (Attr.getNumArgs() != 0) {
2081    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2082    return;
2083  }
2084
2085  if (!isa<FunctionDecl>(d)) {
2086    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2087    << Attr.getName() << 0 /*function*/;
2088    return;
2089  }
2090
2091  d->addAttr(::new (S.Context) NoInlineAttr(Attr.getLoc(), S.Context));
2092}
2093
2094static void HandleNoInstrumentFunctionAttr(Decl *d, const AttributeList &Attr,
2095                                           Sema &S) {
2096  // check the attribute arguments.
2097  if (Attr.getNumArgs() != 0) {
2098    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2099    return;
2100  }
2101
2102  if (!isa<FunctionDecl>(d)) {
2103    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2104    << Attr.getName() << 0 /*function*/;
2105    return;
2106  }
2107
2108  d->addAttr(::new (S.Context) NoInstrumentFunctionAttr(Attr.getLoc(),
2109                                                        S.Context));
2110}
2111
2112static void HandleConstantAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2113  if (S.LangOpts.CUDA) {
2114    // check the attribute arguments.
2115    if (Attr.getNumArgs() != 0) {
2116      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2117      return;
2118    }
2119
2120    if (!isa<VarDecl>(d)) {
2121      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2122        << Attr.getName() << 12 /*variable*/;
2123      return;
2124    }
2125
2126    d->addAttr(::new (S.Context) CUDAConstantAttr(Attr.getLoc(), S.Context));
2127  } else {
2128    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "constant";
2129  }
2130}
2131
2132static void HandleDeviceAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2133  if (S.LangOpts.CUDA) {
2134    // check the attribute arguments.
2135    if (Attr.getNumArgs() != 0) {
2136      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2137      return;
2138    }
2139
2140    if (!isa<FunctionDecl>(d) && !isa<VarDecl>(d)) {
2141      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2142        << Attr.getName() << 2 /*variable and function*/;
2143      return;
2144    }
2145
2146    d->addAttr(::new (S.Context) CUDADeviceAttr(Attr.getLoc(), S.Context));
2147  } else {
2148    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "device";
2149  }
2150}
2151
2152static void HandleGlobalAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2153  if (S.LangOpts.CUDA) {
2154    // check the attribute arguments.
2155    if (Attr.getNumArgs() != 0) {
2156      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2157      return;
2158    }
2159
2160    if (!isa<FunctionDecl>(d)) {
2161      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2162        << Attr.getName() << 0 /*function*/;
2163      return;
2164    }
2165
2166    d->addAttr(::new (S.Context) CUDAGlobalAttr(Attr.getLoc(), S.Context));
2167  } else {
2168    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "global";
2169  }
2170}
2171
2172static void HandleHostAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2173  if (S.LangOpts.CUDA) {
2174    // check the attribute arguments.
2175    if (Attr.getNumArgs() != 0) {
2176      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2177      return;
2178    }
2179
2180    if (!isa<FunctionDecl>(d)) {
2181      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2182        << Attr.getName() << 0 /*function*/;
2183      return;
2184    }
2185
2186    d->addAttr(::new (S.Context) CUDAHostAttr(Attr.getLoc(), S.Context));
2187  } else {
2188    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "host";
2189  }
2190}
2191
2192static void HandleSharedAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2193  if (S.LangOpts.CUDA) {
2194    // check the attribute arguments.
2195    if (Attr.getNumArgs() != 0) {
2196      S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2197      return;
2198    }
2199
2200    if (!isa<VarDecl>(d)) {
2201      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2202        << Attr.getName() << 12 /*variable*/;
2203      return;
2204    }
2205
2206    d->addAttr(::new (S.Context) CUDASharedAttr(Attr.getLoc(), S.Context));
2207  } else {
2208    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "shared";
2209  }
2210}
2211
2212static void HandleGNUInlineAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2213  // check the attribute arguments.
2214  if (Attr.getNumArgs() != 0) {
2215    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2216    return;
2217  }
2218
2219  FunctionDecl *Fn = dyn_cast<FunctionDecl>(d);
2220  if (Fn == 0) {
2221    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2222      << Attr.getName() << 0 /*function*/;
2223    return;
2224  }
2225
2226  if (!Fn->isInlineSpecified()) {
2227    S.Diag(Attr.getLoc(), diag::warn_gnu_inline_attribute_requires_inline);
2228    return;
2229  }
2230
2231  d->addAttr(::new (S.Context) GNUInlineAttr(Attr.getLoc(), S.Context));
2232}
2233
2234static void HandleCallConvAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2235  // Diagnostic is emitted elsewhere: here we store the (valid) Attr
2236  // in the Decl node for syntactic reasoning, e.g., pretty-printing.
2237  assert(Attr.isInvalid() == false);
2238
2239  switch (Attr.getKind()) {
2240  case AttributeList::AT_fastcall:
2241    d->addAttr(::new (S.Context) FastCallAttr(Attr.getLoc(), S.Context));
2242    return;
2243  case AttributeList::AT_stdcall:
2244    d->addAttr(::new (S.Context) StdCallAttr(Attr.getLoc(), S.Context));
2245    return;
2246  case AttributeList::AT_thiscall:
2247    d->addAttr(::new (S.Context) ThisCallAttr(Attr.getLoc(), S.Context));
2248    return;
2249  case AttributeList::AT_cdecl:
2250    d->addAttr(::new (S.Context) CDeclAttr(Attr.getLoc(), S.Context));
2251    return;
2252  case AttributeList::AT_pascal:
2253    d->addAttr(::new (S.Context) PascalAttr(Attr.getLoc(), S.Context));
2254    return;
2255  default:
2256    llvm_unreachable("unexpected attribute kind");
2257    return;
2258  }
2259}
2260
2261static void HandleRegparmAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2262  // check the attribute arguments.
2263  if (Attr.getNumArgs() != 1) {
2264    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 1;
2265    return;
2266  }
2267
2268  if (!isFunctionOrMethod(d)) {
2269    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
2270    << Attr.getName() << 0 /*function*/;
2271    return;
2272  }
2273
2274  Expr *NumParamsExpr = Attr.getArg(0);
2275  llvm::APSInt NumParams(32);
2276  if (NumParamsExpr->isTypeDependent() || NumParamsExpr->isValueDependent() ||
2277      !NumParamsExpr->isIntegerConstantExpr(NumParams, S.Context)) {
2278    S.Diag(Attr.getLoc(), diag::err_attribute_argument_not_int)
2279      << "regparm" << NumParamsExpr->getSourceRange();
2280    return;
2281  }
2282
2283  if (S.Context.Target.getRegParmMax() == 0) {
2284    S.Diag(Attr.getLoc(), diag::err_attribute_regparm_wrong_platform)
2285      << NumParamsExpr->getSourceRange();
2286    return;
2287  }
2288
2289  if (NumParams.getLimitedValue(255) > S.Context.Target.getRegParmMax()) {
2290    S.Diag(Attr.getLoc(), diag::err_attribute_regparm_invalid_number)
2291      << S.Context.Target.getRegParmMax() << NumParamsExpr->getSourceRange();
2292    return;
2293  }
2294
2295  d->addAttr(::new (S.Context) RegparmAttr(Attr.getLoc(), S.Context,
2296                                           NumParams.getZExtValue()));
2297}
2298
2299static void HandleFinalAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2300  // check the attribute arguments.
2301  if (Attr.getNumArgs() != 0) {
2302    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2303    return;
2304  }
2305
2306  if (!isa<CXXRecordDecl>(d)
2307   && (!isa<CXXMethodDecl>(d) || !cast<CXXMethodDecl>(d)->isVirtual())) {
2308    S.Diag(Attr.getLoc(),
2309           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
2310                                   : diag::warn_attribute_wrong_decl_type)
2311      << Attr.getName() << 7 /*virtual method or class*/;
2312    return;
2313  }
2314
2315  // FIXME: Conform to C++0x redeclaration rules.
2316
2317  if (d->getAttr<FinalAttr>()) {
2318    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "final";
2319    return;
2320  }
2321
2322  d->addAttr(::new (S.Context) FinalAttr(Attr.getLoc(), S.Context));
2323}
2324
2325//===----------------------------------------------------------------------===//
2326// C++0x member checking attributes
2327//===----------------------------------------------------------------------===//
2328
2329static void HandleBaseCheckAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2330  if (Attr.getNumArgs() != 0) {
2331    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2332    return;
2333  }
2334
2335  if (!isa<CXXRecordDecl>(d)) {
2336    S.Diag(Attr.getLoc(),
2337           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
2338                                   : diag::warn_attribute_wrong_decl_type)
2339      << Attr.getName() << 9 /*class*/;
2340    return;
2341  }
2342
2343  if (d->getAttr<BaseCheckAttr>()) {
2344    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "base_check";
2345    return;
2346  }
2347
2348  d->addAttr(::new (S.Context) BaseCheckAttr(Attr.getLoc(), S.Context));
2349}
2350
2351static void HandleHidingAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2352  if (Attr.getNumArgs() != 0) {
2353    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2354    return;
2355  }
2356
2357  if (!isa<RecordDecl>(d->getDeclContext())) {
2358    // FIXME: It's not the type that's the problem
2359    S.Diag(Attr.getLoc(),
2360           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
2361                                   : diag::warn_attribute_wrong_decl_type)
2362      << Attr.getName() << 11 /*member*/;
2363    return;
2364  }
2365
2366  // FIXME: Conform to C++0x redeclaration rules.
2367
2368  if (d->getAttr<HidingAttr>()) {
2369    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "hiding";
2370    return;
2371  }
2372
2373  d->addAttr(::new (S.Context) HidingAttr(Attr.getLoc(), S.Context));
2374}
2375
2376static void HandleOverrideAttr(Decl *d, const AttributeList &Attr, Sema &S) {
2377  if (Attr.getNumArgs() != 0) {
2378    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
2379    return;
2380  }
2381
2382  if (!isa<CXXMethodDecl>(d) || !cast<CXXMethodDecl>(d)->isVirtual()) {
2383    // FIXME: It's not the type that's the problem
2384    S.Diag(Attr.getLoc(),
2385           Attr.isCXX0XAttribute() ? diag::err_attribute_wrong_decl_type
2386                                   : diag::warn_attribute_wrong_decl_type)
2387      << Attr.getName() << 10 /*virtual method*/;
2388    return;
2389  }
2390
2391  // FIXME: Conform to C++0x redeclaration rules.
2392
2393  if (d->getAttr<OverrideAttr>()) {
2394    S.Diag(Attr.getLoc(), diag::err_repeat_attribute) << "override";
2395    return;
2396  }
2397
2398  d->addAttr(::new (S.Context) OverrideAttr(Attr.getLoc(), S.Context));
2399}
2400
2401//===----------------------------------------------------------------------===//
2402// Checker-specific attribute handlers.
2403//===----------------------------------------------------------------------===//
2404
2405static void HandleNSReturnsRetainedAttr(Decl *d, const AttributeList &Attr,
2406                                        Sema &S) {
2407
2408  QualType RetTy;
2409
2410  if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(d))
2411    RetTy = MD->getResultType();
2412  else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(d))
2413    RetTy = FD->getResultType();
2414  else {
2415    SourceLocation L = Attr.getLoc();
2416    S.Diag(d->getLocStart(), diag::warn_attribute_wrong_decl_type)
2417        << SourceRange(L, L) << Attr.getName() << 3 /* function or method */;
2418    return;
2419  }
2420
2421  if (!(S.Context.isObjCNSObjectType(RetTy) || RetTy->getAs<PointerType>()
2422        || RetTy->getAs<ObjCObjectPointerType>())) {
2423    SourceLocation L = Attr.getLoc();
2424    S.Diag(d->getLocStart(), diag::warn_ns_attribute_wrong_return_type)
2425      << SourceRange(L, L) << Attr.getName();
2426    return;
2427  }
2428
2429  switch (Attr.getKind()) {
2430    default:
2431      assert(0 && "invalid ownership attribute");
2432      return;
2433    case AttributeList::AT_cf_returns_not_retained:
2434      d->addAttr(::new (S.Context) CFReturnsNotRetainedAttr(Attr.getLoc(),
2435                                                            S.Context));
2436      return;
2437    case AttributeList::AT_ns_returns_not_retained:
2438      d->addAttr(::new (S.Context) NSReturnsNotRetainedAttr(Attr.getLoc(),
2439                                                            S.Context));
2440      return;
2441    case AttributeList::AT_cf_returns_retained:
2442      d->addAttr(::new (S.Context) CFReturnsRetainedAttr(Attr.getLoc(),
2443                                                         S.Context));
2444      return;
2445    case AttributeList::AT_ns_returns_retained:
2446      d->addAttr(::new (S.Context) NSReturnsRetainedAttr(Attr.getLoc(),
2447                                                         S.Context));
2448      return;
2449  };
2450}
2451
2452static bool isKnownDeclSpecAttr(const AttributeList &Attr) {
2453  return Attr.getKind() == AttributeList::AT_dllimport ||
2454         Attr.getKind() == AttributeList::AT_dllexport;
2455}
2456
2457//===----------------------------------------------------------------------===//
2458// Top Level Sema Entry Points
2459//===----------------------------------------------------------------------===//
2460
2461/// ProcessDeclAttribute - Apply the specific attribute to the specified decl if
2462/// the attribute applies to decls.  If the attribute is a type attribute, just
2463/// silently ignore it if a GNU attribute. FIXME: Applying a C++0x attribute to
2464/// the wrong thing is illegal (C++0x [dcl.attr.grammar]/4).
2465static void ProcessDeclAttribute(Scope *scope, Decl *D,
2466                                 const AttributeList &Attr, Sema &S) {
2467  if (Attr.isInvalid())
2468    return;
2469
2470  if (Attr.isDeclspecAttribute() && !isKnownDeclSpecAttr(Attr))
2471    // FIXME: Try to deal with other __declspec attributes!
2472    return;
2473  switch (Attr.getKind()) {
2474  case AttributeList::AT_IBAction:            HandleIBAction(D, Attr, S); break;
2475    case AttributeList::AT_IBOutlet:          HandleIBOutlet(D, Attr, S); break;
2476  case AttributeList::AT_IBOutletCollection:
2477      HandleIBOutletCollection(D, Attr, S); break;
2478  case AttributeList::AT_address_space:
2479  case AttributeList::AT_objc_gc:
2480  case AttributeList::AT_vector_size:
2481  case AttributeList::AT_neon_vector_type:
2482  case AttributeList::AT_neon_polyvector_type:
2483    // Ignore these, these are type attributes, handled by
2484    // ProcessTypeAttributes.
2485    break;
2486  case AttributeList::AT_alias:       HandleAliasAttr       (D, Attr, S); break;
2487  case AttributeList::AT_aligned:     HandleAlignedAttr     (D, Attr, S); break;
2488  case AttributeList::AT_always_inline:
2489    HandleAlwaysInlineAttr  (D, Attr, S); break;
2490  case AttributeList::AT_analyzer_noreturn:
2491    HandleAnalyzerNoReturnAttr  (D, Attr, S); break;
2492  case AttributeList::AT_annotate:    HandleAnnotateAttr    (D, Attr, S); break;
2493  case AttributeList::AT_base_check:  HandleBaseCheckAttr   (D, Attr, S); break;
2494  case AttributeList::AT_carries_dependency:
2495                                      HandleDependencyAttr  (D, Attr, S); break;
2496  case AttributeList::AT_common:      HandleCommonAttr      (D, Attr, S); break;
2497  case AttributeList::AT_constant:    HandleConstantAttr    (D, Attr, S); break;
2498  case AttributeList::AT_constructor: HandleConstructorAttr (D, Attr, S); break;
2499  case AttributeList::AT_deprecated:  HandleDeprecatedAttr  (D, Attr, S); break;
2500  case AttributeList::AT_destructor:  HandleDestructorAttr  (D, Attr, S); break;
2501  case AttributeList::AT_device:      HandleDeviceAttr      (D, Attr, S); break;
2502  case AttributeList::AT_ext_vector_type:
2503    HandleExtVectorTypeAttr(scope, D, Attr, S);
2504    break;
2505  case AttributeList::AT_final:       HandleFinalAttr       (D, Attr, S); break;
2506  case AttributeList::AT_format:      HandleFormatAttr      (D, Attr, S); break;
2507  case AttributeList::AT_format_arg:  HandleFormatArgAttr   (D, Attr, S); break;
2508  case AttributeList::AT_global:      HandleGlobalAttr      (D, Attr, S); break;
2509  case AttributeList::AT_gnu_inline:  HandleGNUInlineAttr   (D, Attr, S); break;
2510  case AttributeList::AT_hiding:      HandleHidingAttr      (D, Attr, S); break;
2511  case AttributeList::AT_host:        HandleHostAttr        (D, Attr, S); break;
2512  case AttributeList::AT_mode:        HandleModeAttr        (D, Attr, S); break;
2513  case AttributeList::AT_malloc:      HandleMallocAttr      (D, Attr, S); break;
2514  case AttributeList::AT_may_alias:   HandleMayAliasAttr    (D, Attr, S); break;
2515  case AttributeList::AT_nocommon:    HandleNoCommonAttr    (D, Attr, S); break;
2516  case AttributeList::AT_nonnull:     HandleNonNullAttr     (D, Attr, S); break;
2517  case AttributeList::AT_ownership_returns:
2518  case AttributeList::AT_ownership_takes:
2519  case AttributeList::AT_ownership_holds:
2520      HandleOwnershipAttr     (D, Attr, S); break;
2521  case AttributeList::AT_naked:       HandleNakedAttr       (D, Attr, S); break;
2522  case AttributeList::AT_noreturn:    HandleNoReturnAttr    (D, Attr, S); break;
2523  case AttributeList::AT_nothrow:     HandleNothrowAttr     (D, Attr, S); break;
2524  case AttributeList::AT_override:    HandleOverrideAttr    (D, Attr, S); break;
2525  case AttributeList::AT_shared:      HandleSharedAttr      (D, Attr, S); break;
2526  case AttributeList::AT_vecreturn:   HandleVecReturnAttr   (D, Attr, S); break;
2527
2528  // Checker-specific.
2529  case AttributeList::AT_ns_returns_not_retained:
2530  case AttributeList::AT_cf_returns_not_retained:
2531  case AttributeList::AT_ns_returns_retained:
2532  case AttributeList::AT_cf_returns_retained:
2533    HandleNSReturnsRetainedAttr(D, Attr, S); break;
2534
2535  case AttributeList::AT_reqd_wg_size:
2536    HandleReqdWorkGroupSize(D, Attr, S); break;
2537
2538  case AttributeList::AT_init_priority:
2539      HandleInitPriorityAttr(D, Attr, S); break;
2540
2541  case AttributeList::AT_packed:      HandlePackedAttr      (D, Attr, S); break;
2542  case AttributeList::AT_section:     HandleSectionAttr     (D, Attr, S); break;
2543  case AttributeList::AT_unavailable: HandleUnavailableAttr (D, Attr, S); break;
2544  case AttributeList::AT_unused:      HandleUnusedAttr      (D, Attr, S); break;
2545  case AttributeList::AT_used:        HandleUsedAttr        (D, Attr, S); break;
2546  case AttributeList::AT_visibility:  HandleVisibilityAttr  (D, Attr, S); break;
2547  case AttributeList::AT_warn_unused_result: HandleWarnUnusedResult(D,Attr,S);
2548    break;
2549  case AttributeList::AT_weak:        HandleWeakAttr        (D, Attr, S); break;
2550  case AttributeList::AT_weakref:     HandleWeakRefAttr     (D, Attr, S); break;
2551  case AttributeList::AT_weak_import: HandleWeakImportAttr  (D, Attr, S); break;
2552  case AttributeList::AT_transparent_union:
2553    HandleTransparentUnionAttr(D, Attr, S);
2554    break;
2555  case AttributeList::AT_objc_exception:
2556    HandleObjCExceptionAttr(D, Attr, S);
2557    break;
2558  case AttributeList::AT_overloadable:HandleOverloadableAttr(D, Attr, S); break;
2559  case AttributeList::AT_nsobject:    HandleObjCNSObject    (D, Attr, S); break;
2560  case AttributeList::AT_blocks:      HandleBlocksAttr      (D, Attr, S); break;
2561  case AttributeList::AT_sentinel:    HandleSentinelAttr    (D, Attr, S); break;
2562  case AttributeList::AT_const:       HandleConstAttr       (D, Attr, S); break;
2563  case AttributeList::AT_pure:        HandlePureAttr        (D, Attr, S); break;
2564  case AttributeList::AT_cleanup:     HandleCleanupAttr     (D, Attr, S); break;
2565  case AttributeList::AT_nodebug:     HandleNoDebugAttr     (D, Attr, S); break;
2566  case AttributeList::AT_noinline:    HandleNoInlineAttr    (D, Attr, S); break;
2567  case AttributeList::AT_regparm:     HandleRegparmAttr     (D, Attr, S); break;
2568  case AttributeList::IgnoredAttribute:
2569    // Just ignore
2570    break;
2571  case AttributeList::AT_no_instrument_function:  // Interacts with -pg.
2572    HandleNoInstrumentFunctionAttr(D, Attr, S);
2573    break;
2574  case AttributeList::AT_stdcall:
2575  case AttributeList::AT_cdecl:
2576  case AttributeList::AT_fastcall:
2577  case AttributeList::AT_thiscall:
2578  case AttributeList::AT_pascal:
2579    HandleCallConvAttr(D, Attr, S);
2580    break;
2581  default:
2582    // Ask target about the attribute.
2583    const TargetAttributesSema &TargetAttrs = S.getTargetAttributesSema();
2584    if (!TargetAttrs.ProcessDeclAttribute(scope, D, Attr, S))
2585      S.Diag(Attr.getLoc(), diag::warn_unknown_attribute_ignored)
2586        << Attr.getName();
2587    break;
2588  }
2589}
2590
2591/// ProcessDeclAttributeList - Apply all the decl attributes in the specified
2592/// attribute list to the specified decl, ignoring any type attributes.
2593void Sema::ProcessDeclAttributeList(Scope *S, Decl *D,
2594                                    const AttributeList *AttrList) {
2595  for (const AttributeList* l = AttrList; l; l = l->getNext()) {
2596    ProcessDeclAttribute(S, D, *l, *this);
2597  }
2598
2599  // GCC accepts
2600  // static int a9 __attribute__((weakref));
2601  // but that looks really pointless. We reject it.
2602  if (D->hasAttr<WeakRefAttr>() && !D->hasAttr<AliasAttr>()) {
2603    Diag(AttrList->getLoc(), diag::err_attribute_weakref_without_alias) <<
2604    dyn_cast<NamedDecl>(D)->getNameAsString();
2605    return;
2606  }
2607}
2608
2609/// DeclClonePragmaWeak - clone existing decl (maybe definition),
2610/// #pragma weak needs a non-definition decl and source may not have one
2611NamedDecl * Sema::DeclClonePragmaWeak(NamedDecl *ND, IdentifierInfo *II) {
2612  assert(isa<FunctionDecl>(ND) || isa<VarDecl>(ND));
2613  NamedDecl *NewD = 0;
2614  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(ND)) {
2615    NewD = FunctionDecl::Create(FD->getASTContext(), FD->getDeclContext(),
2616                                FD->getLocation(), DeclarationName(II),
2617                                FD->getType(), FD->getTypeSourceInfo());
2618    if (FD->getQualifier()) {
2619      FunctionDecl *NewFD = cast<FunctionDecl>(NewD);
2620      NewFD->setQualifierInfo(FD->getQualifier(), FD->getQualifierRange());
2621    }
2622  } else if (VarDecl *VD = dyn_cast<VarDecl>(ND)) {
2623    NewD = VarDecl::Create(VD->getASTContext(), VD->getDeclContext(),
2624                           VD->getLocation(), II,
2625                           VD->getType(), VD->getTypeSourceInfo(),
2626                           VD->getStorageClass(),
2627                           VD->getStorageClassAsWritten());
2628    if (VD->getQualifier()) {
2629      VarDecl *NewVD = cast<VarDecl>(NewD);
2630      NewVD->setQualifierInfo(VD->getQualifier(), VD->getQualifierRange());
2631    }
2632  }
2633  return NewD;
2634}
2635
2636/// DeclApplyPragmaWeak - A declaration (maybe definition) needs #pragma weak
2637/// applied to it, possibly with an alias.
2638void Sema::DeclApplyPragmaWeak(Scope *S, NamedDecl *ND, WeakInfo &W) {
2639  if (W.getUsed()) return; // only do this once
2640  W.setUsed(true);
2641  if (W.getAlias()) { // clone decl, impersonate __attribute(weak,alias(...))
2642    IdentifierInfo *NDId = ND->getIdentifier();
2643    NamedDecl *NewD = DeclClonePragmaWeak(ND, W.getAlias());
2644    NewD->addAttr(::new (Context) AliasAttr(W.getLocation(), Context,
2645                                            NDId->getName()));
2646    NewD->addAttr(::new (Context) WeakAttr(W.getLocation(), Context));
2647    WeakTopLevelDecl.push_back(NewD);
2648    // FIXME: "hideous" code from Sema::LazilyCreateBuiltin
2649    // to insert Decl at TU scope, sorry.
2650    DeclContext *SavedContext = CurContext;
2651    CurContext = Context.getTranslationUnitDecl();
2652    PushOnScopeChains(NewD, S);
2653    CurContext = SavedContext;
2654  } else { // just add weak to existing
2655    ND->addAttr(::new (Context) WeakAttr(W.getLocation(), Context));
2656  }
2657}
2658
2659/// ProcessDeclAttributes - Given a declarator (PD) with attributes indicated in
2660/// it, apply them to D.  This is a bit tricky because PD can have attributes
2661/// specified in many different places, and we need to find and apply them all.
2662void Sema::ProcessDeclAttributes(Scope *S, Decl *D, const Declarator &PD) {
2663  // It's valid to "forward-declare" #pragma weak, in which case we
2664  // have to do this.
2665  if (!WeakUndeclaredIdentifiers.empty()) {
2666    if (NamedDecl *ND = dyn_cast<NamedDecl>(D)) {
2667      if (IdentifierInfo *Id = ND->getIdentifier()) {
2668        llvm::DenseMap<IdentifierInfo*,WeakInfo>::iterator I
2669          = WeakUndeclaredIdentifiers.find(Id);
2670        if (I != WeakUndeclaredIdentifiers.end() && ND->hasLinkage()) {
2671          WeakInfo W = I->second;
2672          DeclApplyPragmaWeak(S, ND, W);
2673          WeakUndeclaredIdentifiers[Id] = W;
2674        }
2675      }
2676    }
2677  }
2678
2679  // Apply decl attributes from the DeclSpec if present.
2680  if (const AttributeList *Attrs = PD.getDeclSpec().getAttributes())
2681    ProcessDeclAttributeList(S, D, Attrs);
2682
2683  // Walk the declarator structure, applying decl attributes that were in a type
2684  // position to the decl itself.  This handles cases like:
2685  //   int *__attr__(x)** D;
2686  // when X is a decl attribute.
2687  for (unsigned i = 0, e = PD.getNumTypeObjects(); i != e; ++i)
2688    if (const AttributeList *Attrs = PD.getTypeObject(i).getAttrs())
2689      ProcessDeclAttributeList(S, D, Attrs);
2690
2691  // Finally, apply any attributes on the decl itself.
2692  if (const AttributeList *Attrs = PD.getAttributes())
2693    ProcessDeclAttributeList(S, D, Attrs);
2694}
2695
2696/// PushParsingDeclaration - Enter a new "scope" of deprecation
2697/// warnings.
2698///
2699/// The state token we use is the start index of this scope
2700/// on the warning stack.
2701Sema::ParsingDeclStackState Sema::PushParsingDeclaration() {
2702  ParsingDeclDepth++;
2703  return (ParsingDeclStackState) DelayedDiagnostics.size();
2704}
2705
2706void Sema::PopParsingDeclaration(ParsingDeclStackState S, Decl *D) {
2707  assert(ParsingDeclDepth > 0 && "empty ParsingDeclaration stack");
2708  ParsingDeclDepth--;
2709
2710  if (DelayedDiagnostics.empty())
2711    return;
2712
2713  unsigned SavedIndex = (unsigned) S;
2714  assert(SavedIndex <= DelayedDiagnostics.size() &&
2715         "saved index is out of bounds");
2716
2717  unsigned E = DelayedDiagnostics.size();
2718
2719  // We only want to actually emit delayed diagnostics when we
2720  // successfully parsed a decl.
2721  if (D) {
2722    // We really do want to start with 0 here.  We get one push for a
2723    // decl spec and another for each declarator;  in a decl group like:
2724    //   deprecated_typedef foo, *bar, baz();
2725    // only the declarator pops will be passed decls.  This is correct;
2726    // we really do need to consider delayed diagnostics from the decl spec
2727    // for each of the different declarations.
2728    for (unsigned I = 0; I != E; ++I) {
2729      if (DelayedDiagnostics[I].Triggered)
2730        continue;
2731
2732      switch (DelayedDiagnostics[I].Kind) {
2733      case DelayedDiagnostic::Deprecation:
2734        HandleDelayedDeprecationCheck(DelayedDiagnostics[I], D);
2735        break;
2736
2737      case DelayedDiagnostic::Access:
2738        HandleDelayedAccessCheck(DelayedDiagnostics[I], D);
2739        break;
2740      }
2741    }
2742  }
2743
2744  // Destroy all the delayed diagnostics we're about to pop off.
2745  for (unsigned I = SavedIndex; I != E; ++I)
2746    DelayedDiagnostics[I].destroy();
2747
2748  DelayedDiagnostics.set_size(SavedIndex);
2749}
2750
2751static bool isDeclDeprecated(Decl *D) {
2752  do {
2753    if (D->hasAttr<DeprecatedAttr>())
2754      return true;
2755  } while ((D = cast_or_null<Decl>(D->getDeclContext())));
2756  return false;
2757}
2758
2759void Sema::HandleDelayedDeprecationCheck(DelayedDiagnostic &DD,
2760                                         Decl *Ctx) {
2761  if (isDeclDeprecated(Ctx))
2762    return;
2763
2764  DD.Triggered = true;
2765  if (!DD.getDeprecationMessage().empty())
2766    Diag(DD.Loc, diag::warn_deprecated_message)
2767      << DD.getDeprecationDecl()->getDeclName()
2768      << DD.getDeprecationMessage();
2769  else
2770    Diag(DD.Loc, diag::warn_deprecated)
2771      << DD.getDeprecationDecl()->getDeclName();
2772}
2773
2774void Sema::EmitDeprecationWarning(NamedDecl *D, llvm::StringRef Message,
2775                                  SourceLocation Loc) {
2776  // Delay if we're currently parsing a declaration.
2777  if (ParsingDeclDepth) {
2778    DelayedDiagnostics.push_back(DelayedDiagnostic::makeDeprecation(Loc, D,
2779                                                                    Message));
2780    return;
2781  }
2782
2783  // Otherwise, don't warn if our current context is deprecated.
2784  if (isDeclDeprecated(cast<Decl>(CurContext)))
2785    return;
2786  if (!Message.empty())
2787    Diag(Loc, diag::warn_deprecated_message) << D->getDeclName()
2788                                             << Message;
2789  else
2790    Diag(Loc, diag::warn_deprecated) << D->getDeclName();
2791}
2792