xref: /minix3/external/bsd/llvm/dist/clang/lib/Sema/SemaCast.cpp (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1f4a2713aSLionel Sambuc //===--- SemaCast.cpp - Semantic Analysis for Casts -----------------------===//
2f4a2713aSLionel Sambuc //
3f4a2713aSLionel Sambuc //                     The LLVM Compiler Infrastructure
4f4a2713aSLionel Sambuc //
5f4a2713aSLionel Sambuc // This file is distributed under the University of Illinois Open Source
6f4a2713aSLionel Sambuc // License. See LICENSE.TXT for details.
7f4a2713aSLionel Sambuc //
8f4a2713aSLionel Sambuc //===----------------------------------------------------------------------===//
9f4a2713aSLionel Sambuc //
10f4a2713aSLionel Sambuc //  This file implements semantic analysis for cast expressions, including
11f4a2713aSLionel Sambuc //  1) C-style casts like '(int) x'
12f4a2713aSLionel Sambuc //  2) C++ functional casts like 'int(x)'
13f4a2713aSLionel Sambuc //  3) C++ named casts like 'static_cast<int>(x)'
14f4a2713aSLionel Sambuc //
15f4a2713aSLionel Sambuc //===----------------------------------------------------------------------===//
16f4a2713aSLionel Sambuc 
17f4a2713aSLionel Sambuc #include "clang/Sema/SemaInternal.h"
18f4a2713aSLionel Sambuc #include "clang/AST/ASTContext.h"
19f4a2713aSLionel Sambuc #include "clang/AST/CXXInheritance.h"
20f4a2713aSLionel Sambuc #include "clang/AST/ExprCXX.h"
21f4a2713aSLionel Sambuc #include "clang/AST/ExprObjC.h"
22f4a2713aSLionel Sambuc #include "clang/AST/RecordLayout.h"
23f4a2713aSLionel Sambuc #include "clang/Basic/PartialDiagnostic.h"
24*0a6a1f1dSLionel Sambuc #include "clang/Basic/TargetInfo.h"
25f4a2713aSLionel Sambuc #include "clang/Sema/Initialization.h"
26f4a2713aSLionel Sambuc #include "llvm/ADT/SmallVector.h"
27f4a2713aSLionel Sambuc #include <set>
28f4a2713aSLionel Sambuc using namespace clang;
29f4a2713aSLionel Sambuc 
30f4a2713aSLionel Sambuc 
31f4a2713aSLionel Sambuc 
32f4a2713aSLionel Sambuc enum TryCastResult {
33f4a2713aSLionel Sambuc   TC_NotApplicable, ///< The cast method is not applicable.
34f4a2713aSLionel Sambuc   TC_Success,       ///< The cast method is appropriate and successful.
35f4a2713aSLionel Sambuc   TC_Failed         ///< The cast method is appropriate, but failed. A
36f4a2713aSLionel Sambuc                     ///< diagnostic has been emitted.
37f4a2713aSLionel Sambuc };
38f4a2713aSLionel Sambuc 
39f4a2713aSLionel Sambuc enum CastType {
40f4a2713aSLionel Sambuc   CT_Const,       ///< const_cast
41f4a2713aSLionel Sambuc   CT_Static,      ///< static_cast
42f4a2713aSLionel Sambuc   CT_Reinterpret, ///< reinterpret_cast
43f4a2713aSLionel Sambuc   CT_Dynamic,     ///< dynamic_cast
44f4a2713aSLionel Sambuc   CT_CStyle,      ///< (Type)expr
45f4a2713aSLionel Sambuc   CT_Functional   ///< Type(expr)
46f4a2713aSLionel Sambuc };
47f4a2713aSLionel Sambuc 
48f4a2713aSLionel Sambuc namespace {
49f4a2713aSLionel Sambuc   struct CastOperation {
CastOperation__anon130919f30111::CastOperation50f4a2713aSLionel Sambuc     CastOperation(Sema &S, QualType destType, ExprResult src)
51f4a2713aSLionel Sambuc       : Self(S), SrcExpr(src), DestType(destType),
52f4a2713aSLionel Sambuc         ResultType(destType.getNonLValueExprType(S.Context)),
53f4a2713aSLionel Sambuc         ValueKind(Expr::getValueKindForType(destType)),
54f4a2713aSLionel Sambuc         Kind(CK_Dependent), IsARCUnbridgedCast(false) {
55f4a2713aSLionel Sambuc 
56f4a2713aSLionel Sambuc       if (const BuiltinType *placeholder =
57f4a2713aSLionel Sambuc             src.get()->getType()->getAsPlaceholderType()) {
58f4a2713aSLionel Sambuc         PlaceholderKind = placeholder->getKind();
59f4a2713aSLionel Sambuc       } else {
60f4a2713aSLionel Sambuc         PlaceholderKind = (BuiltinType::Kind) 0;
61f4a2713aSLionel Sambuc       }
62f4a2713aSLionel Sambuc     }
63f4a2713aSLionel Sambuc 
64f4a2713aSLionel Sambuc     Sema &Self;
65f4a2713aSLionel Sambuc     ExprResult SrcExpr;
66f4a2713aSLionel Sambuc     QualType DestType;
67f4a2713aSLionel Sambuc     QualType ResultType;
68f4a2713aSLionel Sambuc     ExprValueKind ValueKind;
69f4a2713aSLionel Sambuc     CastKind Kind;
70f4a2713aSLionel Sambuc     BuiltinType::Kind PlaceholderKind;
71f4a2713aSLionel Sambuc     CXXCastPath BasePath;
72f4a2713aSLionel Sambuc     bool IsARCUnbridgedCast;
73f4a2713aSLionel Sambuc 
74f4a2713aSLionel Sambuc     SourceRange OpRange;
75f4a2713aSLionel Sambuc     SourceRange DestRange;
76f4a2713aSLionel Sambuc 
77f4a2713aSLionel Sambuc     // Top-level semantics-checking routines.
78f4a2713aSLionel Sambuc     void CheckConstCast();
79f4a2713aSLionel Sambuc     void CheckReinterpretCast();
80f4a2713aSLionel Sambuc     void CheckStaticCast();
81f4a2713aSLionel Sambuc     void CheckDynamicCast();
82f4a2713aSLionel Sambuc     void CheckCXXCStyleCast(bool FunctionalCast, bool ListInitialization);
83f4a2713aSLionel Sambuc     void CheckCStyleCast();
84f4a2713aSLionel Sambuc 
85f4a2713aSLionel Sambuc     /// Complete an apparently-successful cast operation that yields
86f4a2713aSLionel Sambuc     /// the given expression.
complete__anon130919f30111::CastOperation87f4a2713aSLionel Sambuc     ExprResult complete(CastExpr *castExpr) {
88f4a2713aSLionel Sambuc       // If this is an unbridged cast, wrap the result in an implicit
89f4a2713aSLionel Sambuc       // cast that yields the unbridged-cast placeholder type.
90f4a2713aSLionel Sambuc       if (IsARCUnbridgedCast) {
91f4a2713aSLionel Sambuc         castExpr = ImplicitCastExpr::Create(Self.Context,
92f4a2713aSLionel Sambuc                                             Self.Context.ARCUnbridgedCastTy,
93*0a6a1f1dSLionel Sambuc                                             CK_Dependent, castExpr, nullptr,
94f4a2713aSLionel Sambuc                                             castExpr->getValueKind());
95f4a2713aSLionel Sambuc       }
96*0a6a1f1dSLionel Sambuc       return castExpr;
97f4a2713aSLionel Sambuc     }
98f4a2713aSLionel Sambuc 
99f4a2713aSLionel Sambuc     // Internal convenience methods.
100f4a2713aSLionel Sambuc 
101f4a2713aSLionel Sambuc     /// Try to handle the given placeholder expression kind.  Return
102f4a2713aSLionel Sambuc     /// true if the source expression has the appropriate placeholder
103f4a2713aSLionel Sambuc     /// kind.  A placeholder can only be claimed once.
claimPlaceholder__anon130919f30111::CastOperation104f4a2713aSLionel Sambuc     bool claimPlaceholder(BuiltinType::Kind K) {
105f4a2713aSLionel Sambuc       if (PlaceholderKind != K) return false;
106f4a2713aSLionel Sambuc 
107f4a2713aSLionel Sambuc       PlaceholderKind = (BuiltinType::Kind) 0;
108f4a2713aSLionel Sambuc       return true;
109f4a2713aSLionel Sambuc     }
110f4a2713aSLionel Sambuc 
isPlaceholder__anon130919f30111::CastOperation111f4a2713aSLionel Sambuc     bool isPlaceholder() const {
112f4a2713aSLionel Sambuc       return PlaceholderKind != 0;
113f4a2713aSLionel Sambuc     }
isPlaceholder__anon130919f30111::CastOperation114f4a2713aSLionel Sambuc     bool isPlaceholder(BuiltinType::Kind K) const {
115f4a2713aSLionel Sambuc       return PlaceholderKind == K;
116f4a2713aSLionel Sambuc     }
117f4a2713aSLionel Sambuc 
checkCastAlign__anon130919f30111::CastOperation118f4a2713aSLionel Sambuc     void checkCastAlign() {
119f4a2713aSLionel Sambuc       Self.CheckCastAlign(SrcExpr.get(), DestType, OpRange);
120f4a2713aSLionel Sambuc     }
121f4a2713aSLionel Sambuc 
checkObjCARCConversion__anon130919f30111::CastOperation122f4a2713aSLionel Sambuc     void checkObjCARCConversion(Sema::CheckedConversionKind CCK) {
123f4a2713aSLionel Sambuc       assert(Self.getLangOpts().ObjCAutoRefCount);
124f4a2713aSLionel Sambuc 
125f4a2713aSLionel Sambuc       Expr *src = SrcExpr.get();
126f4a2713aSLionel Sambuc       if (Self.CheckObjCARCConversion(OpRange, DestType, src, CCK) ==
127f4a2713aSLionel Sambuc             Sema::ACR_unbridged)
128f4a2713aSLionel Sambuc         IsARCUnbridgedCast = true;
129f4a2713aSLionel Sambuc       SrcExpr = src;
130f4a2713aSLionel Sambuc     }
131f4a2713aSLionel Sambuc 
132f4a2713aSLionel Sambuc     /// Check for and handle non-overload placeholder expressions.
checkNonOverloadPlaceholders__anon130919f30111::CastOperation133f4a2713aSLionel Sambuc     void checkNonOverloadPlaceholders() {
134f4a2713aSLionel Sambuc       if (!isPlaceholder() || isPlaceholder(BuiltinType::Overload))
135f4a2713aSLionel Sambuc         return;
136f4a2713aSLionel Sambuc 
137*0a6a1f1dSLionel Sambuc       SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
138f4a2713aSLionel Sambuc       if (SrcExpr.isInvalid())
139f4a2713aSLionel Sambuc         return;
140f4a2713aSLionel Sambuc       PlaceholderKind = (BuiltinType::Kind) 0;
141f4a2713aSLionel Sambuc     }
142f4a2713aSLionel Sambuc   };
143f4a2713aSLionel Sambuc }
144f4a2713aSLionel Sambuc 
145f4a2713aSLionel Sambuc // The Try functions attempt a specific way of casting. If they succeed, they
146f4a2713aSLionel Sambuc // return TC_Success. If their way of casting is not appropriate for the given
147f4a2713aSLionel Sambuc // arguments, they return TC_NotApplicable and *may* set diag to a diagnostic
148f4a2713aSLionel Sambuc // to emit if no other way succeeds. If their way of casting is appropriate but
149f4a2713aSLionel Sambuc // fails, they return TC_Failed and *must* set diag; they can set it to 0 if
150f4a2713aSLionel Sambuc // they emit a specialized diagnostic.
151f4a2713aSLionel Sambuc // All diagnostics returned by these functions must expect the same three
152f4a2713aSLionel Sambuc // arguments:
153f4a2713aSLionel Sambuc // %0: Cast Type (a value from the CastType enumeration)
154f4a2713aSLionel Sambuc // %1: Source Type
155f4a2713aSLionel Sambuc // %2: Destination Type
156f4a2713aSLionel Sambuc static TryCastResult TryLValueToRValueCast(Sema &Self, Expr *SrcExpr,
157f4a2713aSLionel Sambuc                                            QualType DestType, bool CStyle,
158f4a2713aSLionel Sambuc                                            CastKind &Kind,
159f4a2713aSLionel Sambuc                                            CXXCastPath &BasePath,
160f4a2713aSLionel Sambuc                                            unsigned &msg);
161f4a2713aSLionel Sambuc static TryCastResult TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr,
162f4a2713aSLionel Sambuc                                                QualType DestType, bool CStyle,
163f4a2713aSLionel Sambuc                                                const SourceRange &OpRange,
164f4a2713aSLionel Sambuc                                                unsigned &msg,
165f4a2713aSLionel Sambuc                                                CastKind &Kind,
166f4a2713aSLionel Sambuc                                                CXXCastPath &BasePath);
167f4a2713aSLionel Sambuc static TryCastResult TryStaticPointerDowncast(Sema &Self, QualType SrcType,
168f4a2713aSLionel Sambuc                                               QualType DestType, bool CStyle,
169f4a2713aSLionel Sambuc                                               const SourceRange &OpRange,
170f4a2713aSLionel Sambuc                                               unsigned &msg,
171f4a2713aSLionel Sambuc                                               CastKind &Kind,
172f4a2713aSLionel Sambuc                                               CXXCastPath &BasePath);
173f4a2713aSLionel Sambuc static TryCastResult TryStaticDowncast(Sema &Self, CanQualType SrcType,
174f4a2713aSLionel Sambuc                                        CanQualType DestType, bool CStyle,
175f4a2713aSLionel Sambuc                                        const SourceRange &OpRange,
176f4a2713aSLionel Sambuc                                        QualType OrigSrcType,
177f4a2713aSLionel Sambuc                                        QualType OrigDestType, unsigned &msg,
178f4a2713aSLionel Sambuc                                        CastKind &Kind,
179f4a2713aSLionel Sambuc                                        CXXCastPath &BasePath);
180f4a2713aSLionel Sambuc static TryCastResult TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr,
181f4a2713aSLionel Sambuc                                                QualType SrcType,
182f4a2713aSLionel Sambuc                                                QualType DestType,bool CStyle,
183f4a2713aSLionel Sambuc                                                const SourceRange &OpRange,
184f4a2713aSLionel Sambuc                                                unsigned &msg,
185f4a2713aSLionel Sambuc                                                CastKind &Kind,
186f4a2713aSLionel Sambuc                                                CXXCastPath &BasePath);
187f4a2713aSLionel Sambuc 
188f4a2713aSLionel Sambuc static TryCastResult TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr,
189f4a2713aSLionel Sambuc                                            QualType DestType,
190f4a2713aSLionel Sambuc                                            Sema::CheckedConversionKind CCK,
191f4a2713aSLionel Sambuc                                            const SourceRange &OpRange,
192f4a2713aSLionel Sambuc                                            unsigned &msg, CastKind &Kind,
193f4a2713aSLionel Sambuc                                            bool ListInitialization);
194f4a2713aSLionel Sambuc static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
195f4a2713aSLionel Sambuc                                    QualType DestType,
196f4a2713aSLionel Sambuc                                    Sema::CheckedConversionKind CCK,
197f4a2713aSLionel Sambuc                                    const SourceRange &OpRange,
198f4a2713aSLionel Sambuc                                    unsigned &msg, CastKind &Kind,
199f4a2713aSLionel Sambuc                                    CXXCastPath &BasePath,
200f4a2713aSLionel Sambuc                                    bool ListInitialization);
201f4a2713aSLionel Sambuc static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
202f4a2713aSLionel Sambuc                                   QualType DestType, bool CStyle,
203f4a2713aSLionel Sambuc                                   unsigned &msg);
204f4a2713aSLionel Sambuc static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
205f4a2713aSLionel Sambuc                                         QualType DestType, bool CStyle,
206f4a2713aSLionel Sambuc                                         const SourceRange &OpRange,
207f4a2713aSLionel Sambuc                                         unsigned &msg,
208f4a2713aSLionel Sambuc                                         CastKind &Kind);
209f4a2713aSLionel Sambuc 
210f4a2713aSLionel Sambuc 
211f4a2713aSLionel Sambuc /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
212f4a2713aSLionel Sambuc ExprResult
ActOnCXXNamedCast(SourceLocation OpLoc,tok::TokenKind Kind,SourceLocation LAngleBracketLoc,Declarator & D,SourceLocation RAngleBracketLoc,SourceLocation LParenLoc,Expr * E,SourceLocation RParenLoc)213f4a2713aSLionel Sambuc Sema::ActOnCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
214f4a2713aSLionel Sambuc                         SourceLocation LAngleBracketLoc, Declarator &D,
215f4a2713aSLionel Sambuc                         SourceLocation RAngleBracketLoc,
216f4a2713aSLionel Sambuc                         SourceLocation LParenLoc, Expr *E,
217f4a2713aSLionel Sambuc                         SourceLocation RParenLoc) {
218f4a2713aSLionel Sambuc 
219f4a2713aSLionel Sambuc   assert(!D.isInvalidType());
220f4a2713aSLionel Sambuc 
221f4a2713aSLionel Sambuc   TypeSourceInfo *TInfo = GetTypeForDeclaratorCast(D, E->getType());
222f4a2713aSLionel Sambuc   if (D.isInvalidType())
223f4a2713aSLionel Sambuc     return ExprError();
224f4a2713aSLionel Sambuc 
225f4a2713aSLionel Sambuc   if (getLangOpts().CPlusPlus) {
226f4a2713aSLionel Sambuc     // Check that there are no default arguments (C++ only).
227f4a2713aSLionel Sambuc     CheckExtraCXXDefaultArguments(D);
228f4a2713aSLionel Sambuc   }
229f4a2713aSLionel Sambuc 
230f4a2713aSLionel Sambuc   return BuildCXXNamedCast(OpLoc, Kind, TInfo, E,
231f4a2713aSLionel Sambuc                            SourceRange(LAngleBracketLoc, RAngleBracketLoc),
232f4a2713aSLionel Sambuc                            SourceRange(LParenLoc, RParenLoc));
233f4a2713aSLionel Sambuc }
234f4a2713aSLionel Sambuc 
235f4a2713aSLionel Sambuc ExprResult
BuildCXXNamedCast(SourceLocation OpLoc,tok::TokenKind Kind,TypeSourceInfo * DestTInfo,Expr * E,SourceRange AngleBrackets,SourceRange Parens)236f4a2713aSLionel Sambuc Sema::BuildCXXNamedCast(SourceLocation OpLoc, tok::TokenKind Kind,
237f4a2713aSLionel Sambuc                         TypeSourceInfo *DestTInfo, Expr *E,
238f4a2713aSLionel Sambuc                         SourceRange AngleBrackets, SourceRange Parens) {
239*0a6a1f1dSLionel Sambuc   ExprResult Ex = E;
240f4a2713aSLionel Sambuc   QualType DestType = DestTInfo->getType();
241f4a2713aSLionel Sambuc 
242f4a2713aSLionel Sambuc   // If the type is dependent, we won't do the semantic analysis now.
243*0a6a1f1dSLionel Sambuc   bool TypeDependent =
244*0a6a1f1dSLionel Sambuc       DestType->isDependentType() || Ex.get()->isTypeDependent();
245f4a2713aSLionel Sambuc 
246f4a2713aSLionel Sambuc   CastOperation Op(*this, DestType, E);
247f4a2713aSLionel Sambuc   Op.OpRange = SourceRange(OpLoc, Parens.getEnd());
248f4a2713aSLionel Sambuc   Op.DestRange = AngleBrackets;
249f4a2713aSLionel Sambuc 
250f4a2713aSLionel Sambuc   switch (Kind) {
251f4a2713aSLionel Sambuc   default: llvm_unreachable("Unknown C++ cast!");
252f4a2713aSLionel Sambuc 
253f4a2713aSLionel Sambuc   case tok::kw_const_cast:
254f4a2713aSLionel Sambuc     if (!TypeDependent) {
255f4a2713aSLionel Sambuc       Op.CheckConstCast();
256f4a2713aSLionel Sambuc       if (Op.SrcExpr.isInvalid())
257f4a2713aSLionel Sambuc         return ExprError();
258f4a2713aSLionel Sambuc     }
259f4a2713aSLionel Sambuc     return Op.complete(CXXConstCastExpr::Create(Context, Op.ResultType,
260*0a6a1f1dSLionel Sambuc                                   Op.ValueKind, Op.SrcExpr.get(), DestTInfo,
261f4a2713aSLionel Sambuc                                                 OpLoc, Parens.getEnd(),
262f4a2713aSLionel Sambuc                                                 AngleBrackets));
263f4a2713aSLionel Sambuc 
264f4a2713aSLionel Sambuc   case tok::kw_dynamic_cast: {
265f4a2713aSLionel Sambuc     if (!TypeDependent) {
266f4a2713aSLionel Sambuc       Op.CheckDynamicCast();
267f4a2713aSLionel Sambuc       if (Op.SrcExpr.isInvalid())
268f4a2713aSLionel Sambuc         return ExprError();
269f4a2713aSLionel Sambuc     }
270f4a2713aSLionel Sambuc     return Op.complete(CXXDynamicCastExpr::Create(Context, Op.ResultType,
271*0a6a1f1dSLionel Sambuc                                     Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
272f4a2713aSLionel Sambuc                                                   &Op.BasePath, DestTInfo,
273f4a2713aSLionel Sambuc                                                   OpLoc, Parens.getEnd(),
274f4a2713aSLionel Sambuc                                                   AngleBrackets));
275f4a2713aSLionel Sambuc   }
276f4a2713aSLionel Sambuc   case tok::kw_reinterpret_cast: {
277f4a2713aSLionel Sambuc     if (!TypeDependent) {
278f4a2713aSLionel Sambuc       Op.CheckReinterpretCast();
279f4a2713aSLionel Sambuc       if (Op.SrcExpr.isInvalid())
280f4a2713aSLionel Sambuc         return ExprError();
281f4a2713aSLionel Sambuc     }
282f4a2713aSLionel Sambuc     return Op.complete(CXXReinterpretCastExpr::Create(Context, Op.ResultType,
283*0a6a1f1dSLionel Sambuc                                     Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
284*0a6a1f1dSLionel Sambuc                                                       nullptr, DestTInfo, OpLoc,
285f4a2713aSLionel Sambuc                                                       Parens.getEnd(),
286f4a2713aSLionel Sambuc                                                       AngleBrackets));
287f4a2713aSLionel Sambuc   }
288f4a2713aSLionel Sambuc   case tok::kw_static_cast: {
289f4a2713aSLionel Sambuc     if (!TypeDependent) {
290f4a2713aSLionel Sambuc       Op.CheckStaticCast();
291f4a2713aSLionel Sambuc       if (Op.SrcExpr.isInvalid())
292f4a2713aSLionel Sambuc         return ExprError();
293f4a2713aSLionel Sambuc     }
294f4a2713aSLionel Sambuc 
295f4a2713aSLionel Sambuc     return Op.complete(CXXStaticCastExpr::Create(Context, Op.ResultType,
296*0a6a1f1dSLionel Sambuc                                    Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
297f4a2713aSLionel Sambuc                                                  &Op.BasePath, DestTInfo,
298f4a2713aSLionel Sambuc                                                  OpLoc, Parens.getEnd(),
299f4a2713aSLionel Sambuc                                                  AngleBrackets));
300f4a2713aSLionel Sambuc   }
301f4a2713aSLionel Sambuc   }
302f4a2713aSLionel Sambuc }
303f4a2713aSLionel Sambuc 
304f4a2713aSLionel Sambuc /// Try to diagnose a failed overloaded cast.  Returns true if
305f4a2713aSLionel Sambuc /// diagnostics were emitted.
tryDiagnoseOverloadedCast(Sema & S,CastType CT,SourceRange range,Expr * src,QualType destType,bool listInitialization)306f4a2713aSLionel Sambuc static bool tryDiagnoseOverloadedCast(Sema &S, CastType CT,
307f4a2713aSLionel Sambuc                                       SourceRange range, Expr *src,
308f4a2713aSLionel Sambuc                                       QualType destType,
309f4a2713aSLionel Sambuc                                       bool listInitialization) {
310f4a2713aSLionel Sambuc   switch (CT) {
311f4a2713aSLionel Sambuc   // These cast kinds don't consider user-defined conversions.
312f4a2713aSLionel Sambuc   case CT_Const:
313f4a2713aSLionel Sambuc   case CT_Reinterpret:
314f4a2713aSLionel Sambuc   case CT_Dynamic:
315f4a2713aSLionel Sambuc     return false;
316f4a2713aSLionel Sambuc 
317f4a2713aSLionel Sambuc   // These do.
318f4a2713aSLionel Sambuc   case CT_Static:
319f4a2713aSLionel Sambuc   case CT_CStyle:
320f4a2713aSLionel Sambuc   case CT_Functional:
321f4a2713aSLionel Sambuc     break;
322f4a2713aSLionel Sambuc   }
323f4a2713aSLionel Sambuc 
324f4a2713aSLionel Sambuc   QualType srcType = src->getType();
325f4a2713aSLionel Sambuc   if (!destType->isRecordType() && !srcType->isRecordType())
326f4a2713aSLionel Sambuc     return false;
327f4a2713aSLionel Sambuc 
328f4a2713aSLionel Sambuc   InitializedEntity entity = InitializedEntity::InitializeTemporary(destType);
329f4a2713aSLionel Sambuc   InitializationKind initKind
330f4a2713aSLionel Sambuc     = (CT == CT_CStyle)? InitializationKind::CreateCStyleCast(range.getBegin(),
331f4a2713aSLionel Sambuc                                                       range, listInitialization)
332f4a2713aSLionel Sambuc     : (CT == CT_Functional)? InitializationKind::CreateFunctionalCast(range,
333f4a2713aSLionel Sambuc                                                              listInitialization)
334f4a2713aSLionel Sambuc     : InitializationKind::CreateCast(/*type range?*/ range);
335f4a2713aSLionel Sambuc   InitializationSequence sequence(S, entity, initKind, src);
336f4a2713aSLionel Sambuc 
337f4a2713aSLionel Sambuc   assert(sequence.Failed() && "initialization succeeded on second try?");
338f4a2713aSLionel Sambuc   switch (sequence.getFailureKind()) {
339f4a2713aSLionel Sambuc   default: return false;
340f4a2713aSLionel Sambuc 
341f4a2713aSLionel Sambuc   case InitializationSequence::FK_ConstructorOverloadFailed:
342f4a2713aSLionel Sambuc   case InitializationSequence::FK_UserConversionOverloadFailed:
343f4a2713aSLionel Sambuc     break;
344f4a2713aSLionel Sambuc   }
345f4a2713aSLionel Sambuc 
346f4a2713aSLionel Sambuc   OverloadCandidateSet &candidates = sequence.getFailedCandidateSet();
347f4a2713aSLionel Sambuc 
348f4a2713aSLionel Sambuc   unsigned msg = 0;
349f4a2713aSLionel Sambuc   OverloadCandidateDisplayKind howManyCandidates = OCD_AllCandidates;
350f4a2713aSLionel Sambuc 
351f4a2713aSLionel Sambuc   switch (sequence.getFailedOverloadResult()) {
352f4a2713aSLionel Sambuc   case OR_Success: llvm_unreachable("successful failed overload");
353f4a2713aSLionel Sambuc   case OR_No_Viable_Function:
354f4a2713aSLionel Sambuc     if (candidates.empty())
355f4a2713aSLionel Sambuc       msg = diag::err_ovl_no_conversion_in_cast;
356f4a2713aSLionel Sambuc     else
357f4a2713aSLionel Sambuc       msg = diag::err_ovl_no_viable_conversion_in_cast;
358f4a2713aSLionel Sambuc     howManyCandidates = OCD_AllCandidates;
359f4a2713aSLionel Sambuc     break;
360f4a2713aSLionel Sambuc 
361f4a2713aSLionel Sambuc   case OR_Ambiguous:
362f4a2713aSLionel Sambuc     msg = diag::err_ovl_ambiguous_conversion_in_cast;
363f4a2713aSLionel Sambuc     howManyCandidates = OCD_ViableCandidates;
364f4a2713aSLionel Sambuc     break;
365f4a2713aSLionel Sambuc 
366f4a2713aSLionel Sambuc   case OR_Deleted:
367f4a2713aSLionel Sambuc     msg = diag::err_ovl_deleted_conversion_in_cast;
368f4a2713aSLionel Sambuc     howManyCandidates = OCD_ViableCandidates;
369f4a2713aSLionel Sambuc     break;
370f4a2713aSLionel Sambuc   }
371f4a2713aSLionel Sambuc 
372f4a2713aSLionel Sambuc   S.Diag(range.getBegin(), msg)
373f4a2713aSLionel Sambuc     << CT << srcType << destType
374f4a2713aSLionel Sambuc     << range << src->getSourceRange();
375f4a2713aSLionel Sambuc 
376f4a2713aSLionel Sambuc   candidates.NoteCandidates(S, howManyCandidates, src);
377f4a2713aSLionel Sambuc 
378f4a2713aSLionel Sambuc   return true;
379f4a2713aSLionel Sambuc }
380f4a2713aSLionel Sambuc 
381f4a2713aSLionel Sambuc /// Diagnose a failed cast.
diagnoseBadCast(Sema & S,unsigned msg,CastType castType,SourceRange opRange,Expr * src,QualType destType,bool listInitialization)382f4a2713aSLionel Sambuc static void diagnoseBadCast(Sema &S, unsigned msg, CastType castType,
383f4a2713aSLionel Sambuc                             SourceRange opRange, Expr *src, QualType destType,
384f4a2713aSLionel Sambuc                             bool listInitialization) {
385f4a2713aSLionel Sambuc   if (msg == diag::err_bad_cxx_cast_generic &&
386f4a2713aSLionel Sambuc       tryDiagnoseOverloadedCast(S, castType, opRange, src, destType,
387f4a2713aSLionel Sambuc                                 listInitialization))
388f4a2713aSLionel Sambuc     return;
389f4a2713aSLionel Sambuc 
390f4a2713aSLionel Sambuc   S.Diag(opRange.getBegin(), msg) << castType
391f4a2713aSLionel Sambuc     << src->getType() << destType << opRange << src->getSourceRange();
392f4a2713aSLionel Sambuc }
393f4a2713aSLionel Sambuc 
394f4a2713aSLionel Sambuc /// UnwrapDissimilarPointerTypes - Like Sema::UnwrapSimilarPointerTypes,
395f4a2713aSLionel Sambuc /// this removes one level of indirection from both types, provided that they're
396f4a2713aSLionel Sambuc /// the same kind of pointer (plain or to-member). Unlike the Sema function,
397f4a2713aSLionel Sambuc /// this one doesn't care if the two pointers-to-member don't point into the
398f4a2713aSLionel Sambuc /// same class. This is because CastsAwayConstness doesn't care.
UnwrapDissimilarPointerTypes(QualType & T1,QualType & T2)399f4a2713aSLionel Sambuc static bool UnwrapDissimilarPointerTypes(QualType& T1, QualType& T2) {
400f4a2713aSLionel Sambuc   const PointerType *T1PtrType = T1->getAs<PointerType>(),
401f4a2713aSLionel Sambuc                     *T2PtrType = T2->getAs<PointerType>();
402f4a2713aSLionel Sambuc   if (T1PtrType && T2PtrType) {
403f4a2713aSLionel Sambuc     T1 = T1PtrType->getPointeeType();
404f4a2713aSLionel Sambuc     T2 = T2PtrType->getPointeeType();
405f4a2713aSLionel Sambuc     return true;
406f4a2713aSLionel Sambuc   }
407f4a2713aSLionel Sambuc   const ObjCObjectPointerType *T1ObjCPtrType =
408f4a2713aSLionel Sambuc                                             T1->getAs<ObjCObjectPointerType>(),
409f4a2713aSLionel Sambuc                               *T2ObjCPtrType =
410f4a2713aSLionel Sambuc                                             T2->getAs<ObjCObjectPointerType>();
411f4a2713aSLionel Sambuc   if (T1ObjCPtrType) {
412f4a2713aSLionel Sambuc     if (T2ObjCPtrType) {
413f4a2713aSLionel Sambuc       T1 = T1ObjCPtrType->getPointeeType();
414f4a2713aSLionel Sambuc       T2 = T2ObjCPtrType->getPointeeType();
415f4a2713aSLionel Sambuc       return true;
416f4a2713aSLionel Sambuc     }
417f4a2713aSLionel Sambuc     else if (T2PtrType) {
418f4a2713aSLionel Sambuc       T1 = T1ObjCPtrType->getPointeeType();
419f4a2713aSLionel Sambuc       T2 = T2PtrType->getPointeeType();
420f4a2713aSLionel Sambuc       return true;
421f4a2713aSLionel Sambuc     }
422f4a2713aSLionel Sambuc   }
423f4a2713aSLionel Sambuc   else if (T2ObjCPtrType) {
424f4a2713aSLionel Sambuc     if (T1PtrType) {
425f4a2713aSLionel Sambuc       T2 = T2ObjCPtrType->getPointeeType();
426f4a2713aSLionel Sambuc       T1 = T1PtrType->getPointeeType();
427f4a2713aSLionel Sambuc       return true;
428f4a2713aSLionel Sambuc     }
429f4a2713aSLionel Sambuc   }
430f4a2713aSLionel Sambuc 
431f4a2713aSLionel Sambuc   const MemberPointerType *T1MPType = T1->getAs<MemberPointerType>(),
432f4a2713aSLionel Sambuc                           *T2MPType = T2->getAs<MemberPointerType>();
433f4a2713aSLionel Sambuc   if (T1MPType && T2MPType) {
434f4a2713aSLionel Sambuc     T1 = T1MPType->getPointeeType();
435f4a2713aSLionel Sambuc     T2 = T2MPType->getPointeeType();
436f4a2713aSLionel Sambuc     return true;
437f4a2713aSLionel Sambuc   }
438f4a2713aSLionel Sambuc 
439f4a2713aSLionel Sambuc   const BlockPointerType *T1BPType = T1->getAs<BlockPointerType>(),
440f4a2713aSLionel Sambuc                          *T2BPType = T2->getAs<BlockPointerType>();
441f4a2713aSLionel Sambuc   if (T1BPType && T2BPType) {
442f4a2713aSLionel Sambuc     T1 = T1BPType->getPointeeType();
443f4a2713aSLionel Sambuc     T2 = T2BPType->getPointeeType();
444f4a2713aSLionel Sambuc     return true;
445f4a2713aSLionel Sambuc   }
446f4a2713aSLionel Sambuc 
447f4a2713aSLionel Sambuc   return false;
448f4a2713aSLionel Sambuc }
449f4a2713aSLionel Sambuc 
450f4a2713aSLionel Sambuc /// CastsAwayConstness - Check if the pointer conversion from SrcType to
451f4a2713aSLionel Sambuc /// DestType casts away constness as defined in C++ 5.2.11p8ff. This is used by
452f4a2713aSLionel Sambuc /// the cast checkers.  Both arguments must denote pointer (possibly to member)
453f4a2713aSLionel Sambuc /// types.
454f4a2713aSLionel Sambuc ///
455f4a2713aSLionel Sambuc /// \param CheckCVR Whether to check for const/volatile/restrict qualifiers.
456f4a2713aSLionel Sambuc ///
457f4a2713aSLionel Sambuc /// \param CheckObjCLifetime Whether to check Objective-C lifetime qualifiers.
458f4a2713aSLionel Sambuc static bool
CastsAwayConstness(Sema & Self,QualType SrcType,QualType DestType,bool CheckCVR,bool CheckObjCLifetime,QualType * TheOffendingSrcType=nullptr,QualType * TheOffendingDestType=nullptr,Qualifiers * CastAwayQualifiers=nullptr)459f4a2713aSLionel Sambuc CastsAwayConstness(Sema &Self, QualType SrcType, QualType DestType,
460*0a6a1f1dSLionel Sambuc                    bool CheckCVR, bool CheckObjCLifetime,
461*0a6a1f1dSLionel Sambuc                    QualType *TheOffendingSrcType = nullptr,
462*0a6a1f1dSLionel Sambuc                    QualType *TheOffendingDestType = nullptr,
463*0a6a1f1dSLionel Sambuc                    Qualifiers *CastAwayQualifiers = nullptr) {
464f4a2713aSLionel Sambuc   // If the only checking we care about is for Objective-C lifetime qualifiers,
465f4a2713aSLionel Sambuc   // and we're not in ARC mode, there's nothing to check.
466f4a2713aSLionel Sambuc   if (!CheckCVR && CheckObjCLifetime &&
467f4a2713aSLionel Sambuc       !Self.Context.getLangOpts().ObjCAutoRefCount)
468f4a2713aSLionel Sambuc     return false;
469f4a2713aSLionel Sambuc 
470f4a2713aSLionel Sambuc   // Casting away constness is defined in C++ 5.2.11p8 with reference to
471f4a2713aSLionel Sambuc   // C++ 4.4. We piggyback on Sema::IsQualificationConversion for this, since
472f4a2713aSLionel Sambuc   // the rules are non-trivial. So first we construct Tcv *...cv* as described
473f4a2713aSLionel Sambuc   // in C++ 5.2.11p8.
474f4a2713aSLionel Sambuc   assert((SrcType->isAnyPointerType() || SrcType->isMemberPointerType() ||
475f4a2713aSLionel Sambuc           SrcType->isBlockPointerType()) &&
476f4a2713aSLionel Sambuc          "Source type is not pointer or pointer to member.");
477f4a2713aSLionel Sambuc   assert((DestType->isAnyPointerType() || DestType->isMemberPointerType() ||
478f4a2713aSLionel Sambuc           DestType->isBlockPointerType()) &&
479f4a2713aSLionel Sambuc          "Destination type is not pointer or pointer to member.");
480f4a2713aSLionel Sambuc 
481f4a2713aSLionel Sambuc   QualType UnwrappedSrcType = Self.Context.getCanonicalType(SrcType),
482f4a2713aSLionel Sambuc            UnwrappedDestType = Self.Context.getCanonicalType(DestType);
483f4a2713aSLionel Sambuc   SmallVector<Qualifiers, 8> cv1, cv2;
484f4a2713aSLionel Sambuc 
485f4a2713aSLionel Sambuc   // Find the qualifiers. We only care about cvr-qualifiers for the
486f4a2713aSLionel Sambuc   // purpose of this check, because other qualifiers (address spaces,
487f4a2713aSLionel Sambuc   // Objective-C GC, etc.) are part of the type's identity.
488*0a6a1f1dSLionel Sambuc   QualType PrevUnwrappedSrcType = UnwrappedSrcType;
489*0a6a1f1dSLionel Sambuc   QualType PrevUnwrappedDestType = UnwrappedDestType;
490f4a2713aSLionel Sambuc   while (UnwrapDissimilarPointerTypes(UnwrappedSrcType, UnwrappedDestType)) {
491f4a2713aSLionel Sambuc     // Determine the relevant qualifiers at this level.
492f4a2713aSLionel Sambuc     Qualifiers SrcQuals, DestQuals;
493f4a2713aSLionel Sambuc     Self.Context.getUnqualifiedArrayType(UnwrappedSrcType, SrcQuals);
494f4a2713aSLionel Sambuc     Self.Context.getUnqualifiedArrayType(UnwrappedDestType, DestQuals);
495f4a2713aSLionel Sambuc 
496f4a2713aSLionel Sambuc     Qualifiers RetainedSrcQuals, RetainedDestQuals;
497f4a2713aSLionel Sambuc     if (CheckCVR) {
498f4a2713aSLionel Sambuc       RetainedSrcQuals.setCVRQualifiers(SrcQuals.getCVRQualifiers());
499f4a2713aSLionel Sambuc       RetainedDestQuals.setCVRQualifiers(DestQuals.getCVRQualifiers());
500*0a6a1f1dSLionel Sambuc 
501*0a6a1f1dSLionel Sambuc       if (RetainedSrcQuals != RetainedDestQuals && TheOffendingSrcType &&
502*0a6a1f1dSLionel Sambuc           TheOffendingDestType && CastAwayQualifiers) {
503*0a6a1f1dSLionel Sambuc         *TheOffendingSrcType = PrevUnwrappedSrcType;
504*0a6a1f1dSLionel Sambuc         *TheOffendingDestType = PrevUnwrappedDestType;
505*0a6a1f1dSLionel Sambuc         *CastAwayQualifiers = RetainedSrcQuals - RetainedDestQuals;
506*0a6a1f1dSLionel Sambuc       }
507f4a2713aSLionel Sambuc     }
508f4a2713aSLionel Sambuc 
509f4a2713aSLionel Sambuc     if (CheckObjCLifetime &&
510f4a2713aSLionel Sambuc         !DestQuals.compatiblyIncludesObjCLifetime(SrcQuals))
511f4a2713aSLionel Sambuc       return true;
512f4a2713aSLionel Sambuc 
513f4a2713aSLionel Sambuc     cv1.push_back(RetainedSrcQuals);
514f4a2713aSLionel Sambuc     cv2.push_back(RetainedDestQuals);
515*0a6a1f1dSLionel Sambuc 
516*0a6a1f1dSLionel Sambuc     PrevUnwrappedSrcType = UnwrappedSrcType;
517*0a6a1f1dSLionel Sambuc     PrevUnwrappedDestType = UnwrappedDestType;
518f4a2713aSLionel Sambuc   }
519f4a2713aSLionel Sambuc   if (cv1.empty())
520f4a2713aSLionel Sambuc     return false;
521f4a2713aSLionel Sambuc 
522f4a2713aSLionel Sambuc   // Construct void pointers with those qualifiers (in reverse order of
523f4a2713aSLionel Sambuc   // unwrapping, of course).
524f4a2713aSLionel Sambuc   QualType SrcConstruct = Self.Context.VoidTy;
525f4a2713aSLionel Sambuc   QualType DestConstruct = Self.Context.VoidTy;
526f4a2713aSLionel Sambuc   ASTContext &Context = Self.Context;
527f4a2713aSLionel Sambuc   for (SmallVectorImpl<Qualifiers>::reverse_iterator i1 = cv1.rbegin(),
528f4a2713aSLionel Sambuc                                                      i2 = cv2.rbegin();
529f4a2713aSLionel Sambuc        i1 != cv1.rend(); ++i1, ++i2) {
530f4a2713aSLionel Sambuc     SrcConstruct
531f4a2713aSLionel Sambuc       = Context.getPointerType(Context.getQualifiedType(SrcConstruct, *i1));
532f4a2713aSLionel Sambuc     DestConstruct
533f4a2713aSLionel Sambuc       = Context.getPointerType(Context.getQualifiedType(DestConstruct, *i2));
534f4a2713aSLionel Sambuc   }
535f4a2713aSLionel Sambuc 
536f4a2713aSLionel Sambuc   // Test if they're compatible.
537f4a2713aSLionel Sambuc   bool ObjCLifetimeConversion;
538f4a2713aSLionel Sambuc   return SrcConstruct != DestConstruct &&
539f4a2713aSLionel Sambuc     !Self.IsQualificationConversion(SrcConstruct, DestConstruct, false,
540f4a2713aSLionel Sambuc                                     ObjCLifetimeConversion);
541f4a2713aSLionel Sambuc }
542f4a2713aSLionel Sambuc 
543f4a2713aSLionel Sambuc /// CheckDynamicCast - Check that a dynamic_cast\<DestType\>(SrcExpr) is valid.
544f4a2713aSLionel Sambuc /// Refer to C++ 5.2.7 for details. Dynamic casts are used mostly for runtime-
545f4a2713aSLionel Sambuc /// checked downcasts in class hierarchies.
CheckDynamicCast()546f4a2713aSLionel Sambuc void CastOperation::CheckDynamicCast() {
547f4a2713aSLionel Sambuc   if (ValueKind == VK_RValue)
548*0a6a1f1dSLionel Sambuc     SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
549f4a2713aSLionel Sambuc   else if (isPlaceholder())
550*0a6a1f1dSLionel Sambuc     SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
551f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
552f4a2713aSLionel Sambuc     return;
553f4a2713aSLionel Sambuc 
554f4a2713aSLionel Sambuc   QualType OrigSrcType = SrcExpr.get()->getType();
555f4a2713aSLionel Sambuc   QualType DestType = Self.Context.getCanonicalType(this->DestType);
556f4a2713aSLionel Sambuc 
557f4a2713aSLionel Sambuc   // C++ 5.2.7p1: T shall be a pointer or reference to a complete class type,
558f4a2713aSLionel Sambuc   //   or "pointer to cv void".
559f4a2713aSLionel Sambuc 
560f4a2713aSLionel Sambuc   QualType DestPointee;
561f4a2713aSLionel Sambuc   const PointerType *DestPointer = DestType->getAs<PointerType>();
562*0a6a1f1dSLionel Sambuc   const ReferenceType *DestReference = nullptr;
563f4a2713aSLionel Sambuc   if (DestPointer) {
564f4a2713aSLionel Sambuc     DestPointee = DestPointer->getPointeeType();
565f4a2713aSLionel Sambuc   } else if ((DestReference = DestType->getAs<ReferenceType>())) {
566f4a2713aSLionel Sambuc     DestPointee = DestReference->getPointeeType();
567f4a2713aSLionel Sambuc   } else {
568f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ref_or_ptr)
569f4a2713aSLionel Sambuc       << this->DestType << DestRange;
570f4a2713aSLionel Sambuc     SrcExpr = ExprError();
571f4a2713aSLionel Sambuc     return;
572f4a2713aSLionel Sambuc   }
573f4a2713aSLionel Sambuc 
574f4a2713aSLionel Sambuc   const RecordType *DestRecord = DestPointee->getAs<RecordType>();
575f4a2713aSLionel Sambuc   if (DestPointee->isVoidType()) {
576f4a2713aSLionel Sambuc     assert(DestPointer && "Reference to void is not possible");
577f4a2713aSLionel Sambuc   } else if (DestRecord) {
578f4a2713aSLionel Sambuc     if (Self.RequireCompleteType(OpRange.getBegin(), DestPointee,
579f4a2713aSLionel Sambuc                                  diag::err_bad_dynamic_cast_incomplete,
580f4a2713aSLionel Sambuc                                  DestRange)) {
581f4a2713aSLionel Sambuc       SrcExpr = ExprError();
582f4a2713aSLionel Sambuc       return;
583f4a2713aSLionel Sambuc     }
584f4a2713aSLionel Sambuc   } else {
585f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
586f4a2713aSLionel Sambuc       << DestPointee.getUnqualifiedType() << DestRange;
587f4a2713aSLionel Sambuc     SrcExpr = ExprError();
588f4a2713aSLionel Sambuc     return;
589f4a2713aSLionel Sambuc   }
590f4a2713aSLionel Sambuc 
591f4a2713aSLionel Sambuc   // C++0x 5.2.7p2: If T is a pointer type, v shall be an rvalue of a pointer to
592f4a2713aSLionel Sambuc   //   complete class type, [...]. If T is an lvalue reference type, v shall be
593f4a2713aSLionel Sambuc   //   an lvalue of a complete class type, [...]. If T is an rvalue reference
594f4a2713aSLionel Sambuc   //   type, v shall be an expression having a complete class type, [...]
595f4a2713aSLionel Sambuc   QualType SrcType = Self.Context.getCanonicalType(OrigSrcType);
596f4a2713aSLionel Sambuc   QualType SrcPointee;
597f4a2713aSLionel Sambuc   if (DestPointer) {
598f4a2713aSLionel Sambuc     if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
599f4a2713aSLionel Sambuc       SrcPointee = SrcPointer->getPointeeType();
600f4a2713aSLionel Sambuc     } else {
601f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_ptr)
602f4a2713aSLionel Sambuc         << OrigSrcType << SrcExpr.get()->getSourceRange();
603f4a2713aSLionel Sambuc       SrcExpr = ExprError();
604f4a2713aSLionel Sambuc       return;
605f4a2713aSLionel Sambuc     }
606f4a2713aSLionel Sambuc   } else if (DestReference->isLValueReferenceType()) {
607f4a2713aSLionel Sambuc     if (!SrcExpr.get()->isLValue()) {
608f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_rvalue)
609f4a2713aSLionel Sambuc         << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
610f4a2713aSLionel Sambuc     }
611f4a2713aSLionel Sambuc     SrcPointee = SrcType;
612f4a2713aSLionel Sambuc   } else {
613*0a6a1f1dSLionel Sambuc     // If we're dynamic_casting from a prvalue to an rvalue reference, we need
614*0a6a1f1dSLionel Sambuc     // to materialize the prvalue before we bind the reference to it.
615*0a6a1f1dSLionel Sambuc     if (SrcExpr.get()->isRValue())
616*0a6a1f1dSLionel Sambuc       SrcExpr = new (Self.Context) MaterializeTemporaryExpr(
617*0a6a1f1dSLionel Sambuc           SrcType, SrcExpr.get(), /*IsLValueReference*/false);
618f4a2713aSLionel Sambuc     SrcPointee = SrcType;
619f4a2713aSLionel Sambuc   }
620f4a2713aSLionel Sambuc 
621f4a2713aSLionel Sambuc   const RecordType *SrcRecord = SrcPointee->getAs<RecordType>();
622f4a2713aSLionel Sambuc   if (SrcRecord) {
623f4a2713aSLionel Sambuc     if (Self.RequireCompleteType(OpRange.getBegin(), SrcPointee,
624f4a2713aSLionel Sambuc                                  diag::err_bad_dynamic_cast_incomplete,
625f4a2713aSLionel Sambuc                                  SrcExpr.get())) {
626f4a2713aSLionel Sambuc       SrcExpr = ExprError();
627f4a2713aSLionel Sambuc       return;
628f4a2713aSLionel Sambuc     }
629f4a2713aSLionel Sambuc   } else {
630f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_class)
631f4a2713aSLionel Sambuc       << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
632f4a2713aSLionel Sambuc     SrcExpr = ExprError();
633f4a2713aSLionel Sambuc     return;
634f4a2713aSLionel Sambuc   }
635f4a2713aSLionel Sambuc 
636f4a2713aSLionel Sambuc   assert((DestPointer || DestReference) &&
637f4a2713aSLionel Sambuc     "Bad destination non-ptr/ref slipped through.");
638f4a2713aSLionel Sambuc   assert((DestRecord || DestPointee->isVoidType()) &&
639f4a2713aSLionel Sambuc     "Bad destination pointee slipped through.");
640f4a2713aSLionel Sambuc   assert(SrcRecord && "Bad source pointee slipped through.");
641f4a2713aSLionel Sambuc 
642f4a2713aSLionel Sambuc   // C++ 5.2.7p1: The dynamic_cast operator shall not cast away constness.
643f4a2713aSLionel Sambuc   if (!DestPointee.isAtLeastAsQualifiedAs(SrcPointee)) {
644f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_bad_cxx_cast_qualifiers_away)
645f4a2713aSLionel Sambuc       << CT_Dynamic << OrigSrcType << this->DestType << OpRange;
646f4a2713aSLionel Sambuc     SrcExpr = ExprError();
647f4a2713aSLionel Sambuc     return;
648f4a2713aSLionel Sambuc   }
649f4a2713aSLionel Sambuc 
650f4a2713aSLionel Sambuc   // C++ 5.2.7p3: If the type of v is the same as the required result type,
651f4a2713aSLionel Sambuc   //   [except for cv].
652f4a2713aSLionel Sambuc   if (DestRecord == SrcRecord) {
653f4a2713aSLionel Sambuc     Kind = CK_NoOp;
654f4a2713aSLionel Sambuc     return;
655f4a2713aSLionel Sambuc   }
656f4a2713aSLionel Sambuc 
657f4a2713aSLionel Sambuc   // C++ 5.2.7p5
658f4a2713aSLionel Sambuc   // Upcasts are resolved statically.
659f4a2713aSLionel Sambuc   if (DestRecord && Self.IsDerivedFrom(SrcPointee, DestPointee)) {
660f4a2713aSLionel Sambuc     if (Self.CheckDerivedToBaseConversion(SrcPointee, DestPointee,
661f4a2713aSLionel Sambuc                                            OpRange.getBegin(), OpRange,
662f4a2713aSLionel Sambuc                                            &BasePath)) {
663f4a2713aSLionel Sambuc       SrcExpr = ExprError();
664f4a2713aSLionel Sambuc       return;
665f4a2713aSLionel Sambuc     }
666f4a2713aSLionel Sambuc 
667f4a2713aSLionel Sambuc     Kind = CK_DerivedToBase;
668f4a2713aSLionel Sambuc 
669f4a2713aSLionel Sambuc     // If we are casting to or through a virtual base class, we need a
670f4a2713aSLionel Sambuc     // vtable.
671f4a2713aSLionel Sambuc     if (Self.BasePathInvolvesVirtualBase(BasePath))
672f4a2713aSLionel Sambuc       Self.MarkVTableUsed(OpRange.getBegin(),
673f4a2713aSLionel Sambuc                           cast<CXXRecordDecl>(SrcRecord->getDecl()));
674f4a2713aSLionel Sambuc     return;
675f4a2713aSLionel Sambuc   }
676f4a2713aSLionel Sambuc 
677f4a2713aSLionel Sambuc   // C++ 5.2.7p6: Otherwise, v shall be [polymorphic].
678f4a2713aSLionel Sambuc   const RecordDecl *SrcDecl = SrcRecord->getDecl()->getDefinition();
679f4a2713aSLionel Sambuc   assert(SrcDecl && "Definition missing");
680f4a2713aSLionel Sambuc   if (!cast<CXXRecordDecl>(SrcDecl)->isPolymorphic()) {
681f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_bad_dynamic_cast_not_polymorphic)
682f4a2713aSLionel Sambuc       << SrcPointee.getUnqualifiedType() << SrcExpr.get()->getSourceRange();
683f4a2713aSLionel Sambuc     SrcExpr = ExprError();
684f4a2713aSLionel Sambuc   }
685f4a2713aSLionel Sambuc   Self.MarkVTableUsed(OpRange.getBegin(),
686f4a2713aSLionel Sambuc                       cast<CXXRecordDecl>(SrcRecord->getDecl()));
687f4a2713aSLionel Sambuc 
688f4a2713aSLionel Sambuc   // dynamic_cast is not available with -fno-rtti.
689f4a2713aSLionel Sambuc   // As an exception, dynamic_cast to void* is available because it doesn't
690f4a2713aSLionel Sambuc   // use RTTI.
691f4a2713aSLionel Sambuc   if (!Self.getLangOpts().RTTI && !DestPointee->isVoidType()) {
692f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_no_dynamic_cast_with_fno_rtti);
693f4a2713aSLionel Sambuc     SrcExpr = ExprError();
694f4a2713aSLionel Sambuc     return;
695f4a2713aSLionel Sambuc   }
696f4a2713aSLionel Sambuc 
697f4a2713aSLionel Sambuc   // Done. Everything else is run-time checks.
698f4a2713aSLionel Sambuc   Kind = CK_Dynamic;
699f4a2713aSLionel Sambuc }
700f4a2713aSLionel Sambuc 
701f4a2713aSLionel Sambuc /// CheckConstCast - Check that a const_cast\<DestType\>(SrcExpr) is valid.
702f4a2713aSLionel Sambuc /// Refer to C++ 5.2.11 for details. const_cast is typically used in code
703f4a2713aSLionel Sambuc /// like this:
704f4a2713aSLionel Sambuc /// const char *str = "literal";
705f4a2713aSLionel Sambuc /// legacy_function(const_cast\<char*\>(str));
CheckConstCast()706f4a2713aSLionel Sambuc void CastOperation::CheckConstCast() {
707f4a2713aSLionel Sambuc   if (ValueKind == VK_RValue)
708*0a6a1f1dSLionel Sambuc     SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
709f4a2713aSLionel Sambuc   else if (isPlaceholder())
710*0a6a1f1dSLionel Sambuc     SrcExpr = Self.CheckPlaceholderExpr(SrcExpr.get());
711f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
712f4a2713aSLionel Sambuc     return;
713f4a2713aSLionel Sambuc 
714f4a2713aSLionel Sambuc   unsigned msg = diag::err_bad_cxx_cast_generic;
715f4a2713aSLionel Sambuc   if (TryConstCast(Self, SrcExpr, DestType, /*CStyle*/false, msg) != TC_Success
716f4a2713aSLionel Sambuc       && msg != 0) {
717f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), msg) << CT_Const
718f4a2713aSLionel Sambuc       << SrcExpr.get()->getType() << DestType << OpRange;
719f4a2713aSLionel Sambuc     SrcExpr = ExprError();
720f4a2713aSLionel Sambuc   }
721f4a2713aSLionel Sambuc }
722f4a2713aSLionel Sambuc 
723f4a2713aSLionel Sambuc /// Check that a reinterpret_cast\<DestType\>(SrcExpr) is not used as upcast
724f4a2713aSLionel Sambuc /// or downcast between respective pointers or references.
DiagnoseReinterpretUpDownCast(Sema & Self,const Expr * SrcExpr,QualType DestType,SourceRange OpRange)725f4a2713aSLionel Sambuc static void DiagnoseReinterpretUpDownCast(Sema &Self, const Expr *SrcExpr,
726f4a2713aSLionel Sambuc                                           QualType DestType,
727f4a2713aSLionel Sambuc                                           SourceRange OpRange) {
728f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr->getType();
729f4a2713aSLionel Sambuc   // When casting from pointer or reference, get pointee type; use original
730f4a2713aSLionel Sambuc   // type otherwise.
731f4a2713aSLionel Sambuc   const CXXRecordDecl *SrcPointeeRD = SrcType->getPointeeCXXRecordDecl();
732f4a2713aSLionel Sambuc   const CXXRecordDecl *SrcRD =
733f4a2713aSLionel Sambuc     SrcPointeeRD ? SrcPointeeRD : SrcType->getAsCXXRecordDecl();
734f4a2713aSLionel Sambuc 
735f4a2713aSLionel Sambuc   // Examining subobjects for records is only possible if the complete and
736f4a2713aSLionel Sambuc   // valid definition is available.  Also, template instantiation is not
737f4a2713aSLionel Sambuc   // allowed here.
738f4a2713aSLionel Sambuc   if (!SrcRD || !SrcRD->isCompleteDefinition() || SrcRD->isInvalidDecl())
739f4a2713aSLionel Sambuc     return;
740f4a2713aSLionel Sambuc 
741f4a2713aSLionel Sambuc   const CXXRecordDecl *DestRD = DestType->getPointeeCXXRecordDecl();
742f4a2713aSLionel Sambuc 
743f4a2713aSLionel Sambuc   if (!DestRD || !DestRD->isCompleteDefinition() || DestRD->isInvalidDecl())
744f4a2713aSLionel Sambuc     return;
745f4a2713aSLionel Sambuc 
746f4a2713aSLionel Sambuc   enum {
747f4a2713aSLionel Sambuc     ReinterpretUpcast,
748f4a2713aSLionel Sambuc     ReinterpretDowncast
749f4a2713aSLionel Sambuc   } ReinterpretKind;
750f4a2713aSLionel Sambuc 
751f4a2713aSLionel Sambuc   CXXBasePaths BasePaths;
752f4a2713aSLionel Sambuc 
753f4a2713aSLionel Sambuc   if (SrcRD->isDerivedFrom(DestRD, BasePaths))
754f4a2713aSLionel Sambuc     ReinterpretKind = ReinterpretUpcast;
755f4a2713aSLionel Sambuc   else if (DestRD->isDerivedFrom(SrcRD, BasePaths))
756f4a2713aSLionel Sambuc     ReinterpretKind = ReinterpretDowncast;
757f4a2713aSLionel Sambuc   else
758f4a2713aSLionel Sambuc     return;
759f4a2713aSLionel Sambuc 
760f4a2713aSLionel Sambuc   bool VirtualBase = true;
761f4a2713aSLionel Sambuc   bool NonZeroOffset = false;
762f4a2713aSLionel Sambuc   for (CXXBasePaths::const_paths_iterator I = BasePaths.begin(),
763f4a2713aSLionel Sambuc                                           E = BasePaths.end();
764f4a2713aSLionel Sambuc        I != E; ++I) {
765f4a2713aSLionel Sambuc     const CXXBasePath &Path = *I;
766f4a2713aSLionel Sambuc     CharUnits Offset = CharUnits::Zero();
767f4a2713aSLionel Sambuc     bool IsVirtual = false;
768f4a2713aSLionel Sambuc     for (CXXBasePath::const_iterator IElem = Path.begin(), EElem = Path.end();
769f4a2713aSLionel Sambuc          IElem != EElem; ++IElem) {
770f4a2713aSLionel Sambuc       IsVirtual = IElem->Base->isVirtual();
771f4a2713aSLionel Sambuc       if (IsVirtual)
772f4a2713aSLionel Sambuc         break;
773f4a2713aSLionel Sambuc       const CXXRecordDecl *BaseRD = IElem->Base->getType()->getAsCXXRecordDecl();
774f4a2713aSLionel Sambuc       assert(BaseRD && "Base type should be a valid unqualified class type");
775f4a2713aSLionel Sambuc       // Don't check if any base has invalid declaration or has no definition
776f4a2713aSLionel Sambuc       // since it has no layout info.
777f4a2713aSLionel Sambuc       const CXXRecordDecl *Class = IElem->Class,
778f4a2713aSLionel Sambuc                           *ClassDefinition = Class->getDefinition();
779f4a2713aSLionel Sambuc       if (Class->isInvalidDecl() || !ClassDefinition ||
780f4a2713aSLionel Sambuc           !ClassDefinition->isCompleteDefinition())
781f4a2713aSLionel Sambuc         return;
782f4a2713aSLionel Sambuc 
783f4a2713aSLionel Sambuc       const ASTRecordLayout &DerivedLayout =
784f4a2713aSLionel Sambuc           Self.Context.getASTRecordLayout(Class);
785f4a2713aSLionel Sambuc       Offset += DerivedLayout.getBaseClassOffset(BaseRD);
786f4a2713aSLionel Sambuc     }
787f4a2713aSLionel Sambuc     if (!IsVirtual) {
788f4a2713aSLionel Sambuc       // Don't warn if any path is a non-virtually derived base at offset zero.
789f4a2713aSLionel Sambuc       if (Offset.isZero())
790f4a2713aSLionel Sambuc         return;
791f4a2713aSLionel Sambuc       // Offset makes sense only for non-virtual bases.
792f4a2713aSLionel Sambuc       else
793f4a2713aSLionel Sambuc         NonZeroOffset = true;
794f4a2713aSLionel Sambuc     }
795f4a2713aSLionel Sambuc     VirtualBase = VirtualBase && IsVirtual;
796f4a2713aSLionel Sambuc   }
797f4a2713aSLionel Sambuc 
798f4a2713aSLionel Sambuc   (void) NonZeroOffset; // Silence set but not used warning.
799f4a2713aSLionel Sambuc   assert((VirtualBase || NonZeroOffset) &&
800f4a2713aSLionel Sambuc          "Should have returned if has non-virtual base with zero offset");
801f4a2713aSLionel Sambuc 
802f4a2713aSLionel Sambuc   QualType BaseType =
803f4a2713aSLionel Sambuc       ReinterpretKind == ReinterpretUpcast? DestType : SrcType;
804f4a2713aSLionel Sambuc   QualType DerivedType =
805f4a2713aSLionel Sambuc       ReinterpretKind == ReinterpretUpcast? SrcType : DestType;
806f4a2713aSLionel Sambuc 
807f4a2713aSLionel Sambuc   SourceLocation BeginLoc = OpRange.getBegin();
808f4a2713aSLionel Sambuc   Self.Diag(BeginLoc, diag::warn_reinterpret_different_from_static)
809f4a2713aSLionel Sambuc     << DerivedType << BaseType << !VirtualBase << int(ReinterpretKind)
810f4a2713aSLionel Sambuc     << OpRange;
811f4a2713aSLionel Sambuc   Self.Diag(BeginLoc, diag::note_reinterpret_updowncast_use_static)
812f4a2713aSLionel Sambuc     << int(ReinterpretKind)
813f4a2713aSLionel Sambuc     << FixItHint::CreateReplacement(BeginLoc, "static_cast");
814f4a2713aSLionel Sambuc }
815f4a2713aSLionel Sambuc 
816f4a2713aSLionel Sambuc /// CheckReinterpretCast - Check that a reinterpret_cast\<DestType\>(SrcExpr) is
817f4a2713aSLionel Sambuc /// valid.
818f4a2713aSLionel Sambuc /// Refer to C++ 5.2.10 for details. reinterpret_cast is typically used in code
819f4a2713aSLionel Sambuc /// like this:
820f4a2713aSLionel Sambuc /// char *bytes = reinterpret_cast\<char*\>(int_ptr);
CheckReinterpretCast()821f4a2713aSLionel Sambuc void CastOperation::CheckReinterpretCast() {
822f4a2713aSLionel Sambuc   if (ValueKind == VK_RValue && !isPlaceholder(BuiltinType::Overload))
823*0a6a1f1dSLionel Sambuc     SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
824f4a2713aSLionel Sambuc   else
825f4a2713aSLionel Sambuc     checkNonOverloadPlaceholders();
826f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
827f4a2713aSLionel Sambuc     return;
828f4a2713aSLionel Sambuc 
829f4a2713aSLionel Sambuc   unsigned msg = diag::err_bad_cxx_cast_generic;
830f4a2713aSLionel Sambuc   TryCastResult tcr =
831f4a2713aSLionel Sambuc     TryReinterpretCast(Self, SrcExpr, DestType,
832f4a2713aSLionel Sambuc                        /*CStyle*/false, OpRange, msg, Kind);
833f4a2713aSLionel Sambuc   if (tcr != TC_Success && msg != 0)
834f4a2713aSLionel Sambuc   {
835f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
836f4a2713aSLionel Sambuc       return;
837f4a2713aSLionel Sambuc     if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
838f4a2713aSLionel Sambuc       //FIXME: &f<int>; is overloaded and resolvable
839f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_overload)
840f4a2713aSLionel Sambuc         << OverloadExpr::find(SrcExpr.get()).Expression->getName()
841f4a2713aSLionel Sambuc         << DestType << OpRange;
842f4a2713aSLionel Sambuc       Self.NoteAllOverloadCandidates(SrcExpr.get());
843f4a2713aSLionel Sambuc 
844f4a2713aSLionel Sambuc     } else {
845f4a2713aSLionel Sambuc       diagnoseBadCast(Self, msg, CT_Reinterpret, OpRange, SrcExpr.get(),
846f4a2713aSLionel Sambuc                       DestType, /*listInitialization=*/false);
847f4a2713aSLionel Sambuc     }
848f4a2713aSLionel Sambuc     SrcExpr = ExprError();
849f4a2713aSLionel Sambuc   } else if (tcr == TC_Success) {
850f4a2713aSLionel Sambuc     if (Self.getLangOpts().ObjCAutoRefCount)
851f4a2713aSLionel Sambuc       checkObjCARCConversion(Sema::CCK_OtherCast);
852f4a2713aSLionel Sambuc     DiagnoseReinterpretUpDownCast(Self, SrcExpr.get(), DestType, OpRange);
853f4a2713aSLionel Sambuc   }
854f4a2713aSLionel Sambuc }
855f4a2713aSLionel Sambuc 
856f4a2713aSLionel Sambuc 
857f4a2713aSLionel Sambuc /// CheckStaticCast - Check that a static_cast\<DestType\>(SrcExpr) is valid.
858f4a2713aSLionel Sambuc /// Refer to C++ 5.2.9 for details. Static casts are mostly used for making
859f4a2713aSLionel Sambuc /// implicit conversions explicit and getting rid of data loss warnings.
CheckStaticCast()860f4a2713aSLionel Sambuc void CastOperation::CheckStaticCast() {
861f4a2713aSLionel Sambuc   if (isPlaceholder()) {
862f4a2713aSLionel Sambuc     checkNonOverloadPlaceholders();
863f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
864f4a2713aSLionel Sambuc       return;
865f4a2713aSLionel Sambuc   }
866f4a2713aSLionel Sambuc 
867f4a2713aSLionel Sambuc   // This test is outside everything else because it's the only case where
868f4a2713aSLionel Sambuc   // a non-lvalue-reference target type does not lead to decay.
869f4a2713aSLionel Sambuc   // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
870f4a2713aSLionel Sambuc   if (DestType->isVoidType()) {
871f4a2713aSLionel Sambuc     Kind = CK_ToVoid;
872f4a2713aSLionel Sambuc 
873f4a2713aSLionel Sambuc     if (claimPlaceholder(BuiltinType::Overload)) {
874f4a2713aSLionel Sambuc       Self.ResolveAndFixSingleFunctionTemplateSpecialization(SrcExpr,
875f4a2713aSLionel Sambuc                 false, // Decay Function to ptr
876f4a2713aSLionel Sambuc                 true, // Complain
877f4a2713aSLionel Sambuc                 OpRange, DestType, diag::err_bad_static_cast_overload);
878f4a2713aSLionel Sambuc       if (SrcExpr.isInvalid())
879f4a2713aSLionel Sambuc         return;
880f4a2713aSLionel Sambuc     }
881f4a2713aSLionel Sambuc 
882*0a6a1f1dSLionel Sambuc     SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
883f4a2713aSLionel Sambuc     return;
884f4a2713aSLionel Sambuc   }
885f4a2713aSLionel Sambuc 
886f4a2713aSLionel Sambuc   if (ValueKind == VK_RValue && !DestType->isRecordType() &&
887f4a2713aSLionel Sambuc       !isPlaceholder(BuiltinType::Overload)) {
888*0a6a1f1dSLionel Sambuc     SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
889f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid()) // if conversion failed, don't report another error
890f4a2713aSLionel Sambuc       return;
891f4a2713aSLionel Sambuc   }
892f4a2713aSLionel Sambuc 
893f4a2713aSLionel Sambuc   unsigned msg = diag::err_bad_cxx_cast_generic;
894f4a2713aSLionel Sambuc   TryCastResult tcr
895f4a2713aSLionel Sambuc     = TryStaticCast(Self, SrcExpr, DestType, Sema::CCK_OtherCast, OpRange, msg,
896f4a2713aSLionel Sambuc                     Kind, BasePath, /*ListInitialization=*/false);
897f4a2713aSLionel Sambuc   if (tcr != TC_Success && msg != 0) {
898f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
899f4a2713aSLionel Sambuc       return;
900f4a2713aSLionel Sambuc     if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
901f4a2713aSLionel Sambuc       OverloadExpr* oe = OverloadExpr::find(SrcExpr.get()).Expression;
902f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::err_bad_static_cast_overload)
903f4a2713aSLionel Sambuc         << oe->getName() << DestType << OpRange
904f4a2713aSLionel Sambuc         << oe->getQualifierLoc().getSourceRange();
905f4a2713aSLionel Sambuc       Self.NoteAllOverloadCandidates(SrcExpr.get());
906f4a2713aSLionel Sambuc     } else {
907f4a2713aSLionel Sambuc       diagnoseBadCast(Self, msg, CT_Static, OpRange, SrcExpr.get(), DestType,
908f4a2713aSLionel Sambuc                       /*listInitialization=*/false);
909f4a2713aSLionel Sambuc     }
910f4a2713aSLionel Sambuc     SrcExpr = ExprError();
911f4a2713aSLionel Sambuc   } else if (tcr == TC_Success) {
912f4a2713aSLionel Sambuc     if (Kind == CK_BitCast)
913f4a2713aSLionel Sambuc       checkCastAlign();
914f4a2713aSLionel Sambuc     if (Self.getLangOpts().ObjCAutoRefCount)
915f4a2713aSLionel Sambuc       checkObjCARCConversion(Sema::CCK_OtherCast);
916f4a2713aSLionel Sambuc   } else if (Kind == CK_BitCast) {
917f4a2713aSLionel Sambuc     checkCastAlign();
918f4a2713aSLionel Sambuc   }
919f4a2713aSLionel Sambuc }
920f4a2713aSLionel Sambuc 
921f4a2713aSLionel Sambuc /// TryStaticCast - Check if a static cast can be performed, and do so if
922f4a2713aSLionel Sambuc /// possible. If @p CStyle, ignore access restrictions on hierarchy casting
923f4a2713aSLionel Sambuc /// and casting away constness.
TryStaticCast(Sema & Self,ExprResult & SrcExpr,QualType DestType,Sema::CheckedConversionKind CCK,const SourceRange & OpRange,unsigned & msg,CastKind & Kind,CXXCastPath & BasePath,bool ListInitialization)924f4a2713aSLionel Sambuc static TryCastResult TryStaticCast(Sema &Self, ExprResult &SrcExpr,
925f4a2713aSLionel Sambuc                                    QualType DestType,
926f4a2713aSLionel Sambuc                                    Sema::CheckedConversionKind CCK,
927f4a2713aSLionel Sambuc                                    const SourceRange &OpRange, unsigned &msg,
928f4a2713aSLionel Sambuc                                    CastKind &Kind, CXXCastPath &BasePath,
929f4a2713aSLionel Sambuc                                    bool ListInitialization) {
930f4a2713aSLionel Sambuc   // Determine whether we have the semantics of a C-style cast.
931f4a2713aSLionel Sambuc   bool CStyle
932f4a2713aSLionel Sambuc     = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
933f4a2713aSLionel Sambuc 
934f4a2713aSLionel Sambuc   // The order the tests is not entirely arbitrary. There is one conversion
935f4a2713aSLionel Sambuc   // that can be handled in two different ways. Given:
936f4a2713aSLionel Sambuc   // struct A {};
937f4a2713aSLionel Sambuc   // struct B : public A {
938f4a2713aSLionel Sambuc   //   B(); B(const A&);
939f4a2713aSLionel Sambuc   // };
940f4a2713aSLionel Sambuc   // const A &a = B();
941f4a2713aSLionel Sambuc   // the cast static_cast<const B&>(a) could be seen as either a static
942f4a2713aSLionel Sambuc   // reference downcast, or an explicit invocation of the user-defined
943f4a2713aSLionel Sambuc   // conversion using B's conversion constructor.
944f4a2713aSLionel Sambuc   // DR 427 specifies that the downcast is to be applied here.
945f4a2713aSLionel Sambuc 
946f4a2713aSLionel Sambuc   // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
947f4a2713aSLionel Sambuc   // Done outside this function.
948f4a2713aSLionel Sambuc 
949f4a2713aSLionel Sambuc   TryCastResult tcr;
950f4a2713aSLionel Sambuc 
951f4a2713aSLionel Sambuc   // C++ 5.2.9p5, reference downcast.
952f4a2713aSLionel Sambuc   // See the function for details.
953f4a2713aSLionel Sambuc   // DR 427 specifies that this is to be applied before paragraph 2.
954f4a2713aSLionel Sambuc   tcr = TryStaticReferenceDowncast(Self, SrcExpr.get(), DestType, CStyle,
955f4a2713aSLionel Sambuc                                    OpRange, msg, Kind, BasePath);
956f4a2713aSLionel Sambuc   if (tcr != TC_NotApplicable)
957f4a2713aSLionel Sambuc     return tcr;
958f4a2713aSLionel Sambuc 
959f4a2713aSLionel Sambuc   // C++0x [expr.static.cast]p3:
960f4a2713aSLionel Sambuc   //   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to cv2
961f4a2713aSLionel Sambuc   //   T2" if "cv2 T2" is reference-compatible with "cv1 T1".
962f4a2713aSLionel Sambuc   tcr = TryLValueToRValueCast(Self, SrcExpr.get(), DestType, CStyle, Kind,
963f4a2713aSLionel Sambuc                               BasePath, msg);
964f4a2713aSLionel Sambuc   if (tcr != TC_NotApplicable)
965f4a2713aSLionel Sambuc     return tcr;
966f4a2713aSLionel Sambuc 
967f4a2713aSLionel Sambuc   // C++ 5.2.9p2: An expression e can be explicitly converted to a type T
968f4a2713aSLionel Sambuc   //   [...] if the declaration "T t(e);" is well-formed, [...].
969f4a2713aSLionel Sambuc   tcr = TryStaticImplicitCast(Self, SrcExpr, DestType, CCK, OpRange, msg,
970f4a2713aSLionel Sambuc                               Kind, ListInitialization);
971f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid())
972f4a2713aSLionel Sambuc     return TC_Failed;
973f4a2713aSLionel Sambuc   if (tcr != TC_NotApplicable)
974f4a2713aSLionel Sambuc     return tcr;
975f4a2713aSLionel Sambuc 
976f4a2713aSLionel Sambuc   // C++ 5.2.9p6: May apply the reverse of any standard conversion, except
977f4a2713aSLionel Sambuc   // lvalue-to-rvalue, array-to-pointer, function-to-pointer, and boolean
978f4a2713aSLionel Sambuc   // conversions, subject to further restrictions.
979f4a2713aSLionel Sambuc   // Also, C++ 5.2.9p1 forbids casting away constness, which makes reversal
980f4a2713aSLionel Sambuc   // of qualification conversions impossible.
981f4a2713aSLionel Sambuc   // In the CStyle case, the earlier attempt to const_cast should have taken
982f4a2713aSLionel Sambuc   // care of reverse qualification conversions.
983f4a2713aSLionel Sambuc 
984f4a2713aSLionel Sambuc   QualType SrcType = Self.Context.getCanonicalType(SrcExpr.get()->getType());
985f4a2713aSLionel Sambuc 
986f4a2713aSLionel Sambuc   // C++0x 5.2.9p9: A value of a scoped enumeration type can be explicitly
987f4a2713aSLionel Sambuc   // converted to an integral type. [...] A value of a scoped enumeration type
988f4a2713aSLionel Sambuc   // can also be explicitly converted to a floating-point type [...].
989f4a2713aSLionel Sambuc   if (const EnumType *Enum = SrcType->getAs<EnumType>()) {
990f4a2713aSLionel Sambuc     if (Enum->getDecl()->isScoped()) {
991f4a2713aSLionel Sambuc       if (DestType->isBooleanType()) {
992f4a2713aSLionel Sambuc         Kind = CK_IntegralToBoolean;
993f4a2713aSLionel Sambuc         return TC_Success;
994f4a2713aSLionel Sambuc       } else if (DestType->isIntegralType(Self.Context)) {
995f4a2713aSLionel Sambuc         Kind = CK_IntegralCast;
996f4a2713aSLionel Sambuc         return TC_Success;
997f4a2713aSLionel Sambuc       } else if (DestType->isRealFloatingType()) {
998f4a2713aSLionel Sambuc         Kind = CK_IntegralToFloating;
999f4a2713aSLionel Sambuc         return TC_Success;
1000f4a2713aSLionel Sambuc       }
1001f4a2713aSLionel Sambuc     }
1002f4a2713aSLionel Sambuc   }
1003f4a2713aSLionel Sambuc 
1004f4a2713aSLionel Sambuc   // Reverse integral promotion/conversion. All such conversions are themselves
1005f4a2713aSLionel Sambuc   // again integral promotions or conversions and are thus already handled by
1006f4a2713aSLionel Sambuc   // p2 (TryDirectInitialization above).
1007f4a2713aSLionel Sambuc   // (Note: any data loss warnings should be suppressed.)
1008f4a2713aSLionel Sambuc   // The exception is the reverse of enum->integer, i.e. integer->enum (and
1009f4a2713aSLionel Sambuc   // enum->enum). See also C++ 5.2.9p7.
1010f4a2713aSLionel Sambuc   // The same goes for reverse floating point promotion/conversion and
1011f4a2713aSLionel Sambuc   // floating-integral conversions. Again, only floating->enum is relevant.
1012f4a2713aSLionel Sambuc   if (DestType->isEnumeralType()) {
1013f4a2713aSLionel Sambuc     if (SrcType->isIntegralOrEnumerationType()) {
1014f4a2713aSLionel Sambuc       Kind = CK_IntegralCast;
1015f4a2713aSLionel Sambuc       return TC_Success;
1016f4a2713aSLionel Sambuc     } else if (SrcType->isRealFloatingType())   {
1017f4a2713aSLionel Sambuc       Kind = CK_FloatingToIntegral;
1018f4a2713aSLionel Sambuc       return TC_Success;
1019f4a2713aSLionel Sambuc     }
1020f4a2713aSLionel Sambuc   }
1021f4a2713aSLionel Sambuc 
1022f4a2713aSLionel Sambuc   // Reverse pointer upcast. C++ 4.10p3 specifies pointer upcast.
1023f4a2713aSLionel Sambuc   // C++ 5.2.9p8 additionally disallows a cast path through virtual inheritance.
1024f4a2713aSLionel Sambuc   tcr = TryStaticPointerDowncast(Self, SrcType, DestType, CStyle, OpRange, msg,
1025f4a2713aSLionel Sambuc                                  Kind, BasePath);
1026f4a2713aSLionel Sambuc   if (tcr != TC_NotApplicable)
1027f4a2713aSLionel Sambuc     return tcr;
1028f4a2713aSLionel Sambuc 
1029f4a2713aSLionel Sambuc   // Reverse member pointer conversion. C++ 4.11 specifies member pointer
1030f4a2713aSLionel Sambuc   // conversion. C++ 5.2.9p9 has additional information.
1031f4a2713aSLionel Sambuc   // DR54's access restrictions apply here also.
1032f4a2713aSLionel Sambuc   tcr = TryStaticMemberPointerUpcast(Self, SrcExpr, SrcType, DestType, CStyle,
1033f4a2713aSLionel Sambuc                                      OpRange, msg, Kind, BasePath);
1034f4a2713aSLionel Sambuc   if (tcr != TC_NotApplicable)
1035f4a2713aSLionel Sambuc     return tcr;
1036f4a2713aSLionel Sambuc 
1037f4a2713aSLionel Sambuc   // Reverse pointer conversion to void*. C++ 4.10.p2 specifies conversion to
1038f4a2713aSLionel Sambuc   // void*. C++ 5.2.9p10 specifies additional restrictions, which really is
1039f4a2713aSLionel Sambuc   // just the usual constness stuff.
1040f4a2713aSLionel Sambuc   if (const PointerType *SrcPointer = SrcType->getAs<PointerType>()) {
1041f4a2713aSLionel Sambuc     QualType SrcPointee = SrcPointer->getPointeeType();
1042f4a2713aSLionel Sambuc     if (SrcPointee->isVoidType()) {
1043f4a2713aSLionel Sambuc       if (const PointerType *DestPointer = DestType->getAs<PointerType>()) {
1044f4a2713aSLionel Sambuc         QualType DestPointee = DestPointer->getPointeeType();
1045f4a2713aSLionel Sambuc         if (DestPointee->isIncompleteOrObjectType()) {
1046f4a2713aSLionel Sambuc           // This is definitely the intended conversion, but it might fail due
1047f4a2713aSLionel Sambuc           // to a qualifier violation. Note that we permit Objective-C lifetime
1048f4a2713aSLionel Sambuc           // and GC qualifier mismatches here.
1049f4a2713aSLionel Sambuc           if (!CStyle) {
1050f4a2713aSLionel Sambuc             Qualifiers DestPointeeQuals = DestPointee.getQualifiers();
1051f4a2713aSLionel Sambuc             Qualifiers SrcPointeeQuals = SrcPointee.getQualifiers();
1052f4a2713aSLionel Sambuc             DestPointeeQuals.removeObjCGCAttr();
1053f4a2713aSLionel Sambuc             DestPointeeQuals.removeObjCLifetime();
1054f4a2713aSLionel Sambuc             SrcPointeeQuals.removeObjCGCAttr();
1055f4a2713aSLionel Sambuc             SrcPointeeQuals.removeObjCLifetime();
1056f4a2713aSLionel Sambuc             if (DestPointeeQuals != SrcPointeeQuals &&
1057f4a2713aSLionel Sambuc                 !DestPointeeQuals.compatiblyIncludes(SrcPointeeQuals)) {
1058f4a2713aSLionel Sambuc               msg = diag::err_bad_cxx_cast_qualifiers_away;
1059f4a2713aSLionel Sambuc               return TC_Failed;
1060f4a2713aSLionel Sambuc             }
1061f4a2713aSLionel Sambuc           }
1062f4a2713aSLionel Sambuc           Kind = CK_BitCast;
1063f4a2713aSLionel Sambuc           return TC_Success;
1064f4a2713aSLionel Sambuc         }
1065f4a2713aSLionel Sambuc       }
1066f4a2713aSLionel Sambuc       else if (DestType->isObjCObjectPointerType()) {
1067f4a2713aSLionel Sambuc         // allow both c-style cast and static_cast of objective-c pointers as
1068f4a2713aSLionel Sambuc         // they are pervasive.
1069f4a2713aSLionel Sambuc         Kind = CK_CPointerToObjCPointerCast;
1070f4a2713aSLionel Sambuc         return TC_Success;
1071f4a2713aSLionel Sambuc       }
1072f4a2713aSLionel Sambuc       else if (CStyle && DestType->isBlockPointerType()) {
1073f4a2713aSLionel Sambuc         // allow c-style cast of void * to block pointers.
1074f4a2713aSLionel Sambuc         Kind = CK_AnyPointerToBlockPointerCast;
1075f4a2713aSLionel Sambuc         return TC_Success;
1076f4a2713aSLionel Sambuc       }
1077f4a2713aSLionel Sambuc     }
1078f4a2713aSLionel Sambuc   }
1079f4a2713aSLionel Sambuc   // Allow arbitray objective-c pointer conversion with static casts.
1080f4a2713aSLionel Sambuc   if (SrcType->isObjCObjectPointerType() &&
1081f4a2713aSLionel Sambuc       DestType->isObjCObjectPointerType()) {
1082f4a2713aSLionel Sambuc     Kind = CK_BitCast;
1083f4a2713aSLionel Sambuc     return TC_Success;
1084f4a2713aSLionel Sambuc   }
1085*0a6a1f1dSLionel Sambuc   // Allow ns-pointer to cf-pointer conversion in either direction
1086*0a6a1f1dSLionel Sambuc   // with static casts.
1087*0a6a1f1dSLionel Sambuc   if (!CStyle &&
1088*0a6a1f1dSLionel Sambuc       Self.CheckTollFreeBridgeStaticCast(DestType, SrcExpr.get(), Kind))
1089*0a6a1f1dSLionel Sambuc     return TC_Success;
1090f4a2713aSLionel Sambuc 
1091f4a2713aSLionel Sambuc   // We tried everything. Everything! Nothing works! :-(
1092f4a2713aSLionel Sambuc   return TC_NotApplicable;
1093f4a2713aSLionel Sambuc }
1094f4a2713aSLionel Sambuc 
1095f4a2713aSLionel Sambuc /// Tests whether a conversion according to N2844 is valid.
1096f4a2713aSLionel Sambuc TryCastResult
TryLValueToRValueCast(Sema & Self,Expr * SrcExpr,QualType DestType,bool CStyle,CastKind & Kind,CXXCastPath & BasePath,unsigned & msg)1097f4a2713aSLionel Sambuc TryLValueToRValueCast(Sema &Self, Expr *SrcExpr, QualType DestType,
1098f4a2713aSLionel Sambuc                       bool CStyle, CastKind &Kind, CXXCastPath &BasePath,
1099f4a2713aSLionel Sambuc                       unsigned &msg) {
1100f4a2713aSLionel Sambuc   // C++0x [expr.static.cast]p3:
1101f4a2713aSLionel Sambuc   //   A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
1102f4a2713aSLionel Sambuc   //   cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1".
1103f4a2713aSLionel Sambuc   const RValueReferenceType *R = DestType->getAs<RValueReferenceType>();
1104f4a2713aSLionel Sambuc   if (!R)
1105f4a2713aSLionel Sambuc     return TC_NotApplicable;
1106f4a2713aSLionel Sambuc 
1107f4a2713aSLionel Sambuc   if (!SrcExpr->isGLValue())
1108f4a2713aSLionel Sambuc     return TC_NotApplicable;
1109f4a2713aSLionel Sambuc 
1110f4a2713aSLionel Sambuc   // Because we try the reference downcast before this function, from now on
1111f4a2713aSLionel Sambuc   // this is the only cast possibility, so we issue an error if we fail now.
1112f4a2713aSLionel Sambuc   // FIXME: Should allow casting away constness if CStyle.
1113f4a2713aSLionel Sambuc   bool DerivedToBase;
1114f4a2713aSLionel Sambuc   bool ObjCConversion;
1115f4a2713aSLionel Sambuc   bool ObjCLifetimeConversion;
1116f4a2713aSLionel Sambuc   QualType FromType = SrcExpr->getType();
1117f4a2713aSLionel Sambuc   QualType ToType = R->getPointeeType();
1118f4a2713aSLionel Sambuc   if (CStyle) {
1119f4a2713aSLionel Sambuc     FromType = FromType.getUnqualifiedType();
1120f4a2713aSLionel Sambuc     ToType = ToType.getUnqualifiedType();
1121f4a2713aSLionel Sambuc   }
1122f4a2713aSLionel Sambuc 
1123f4a2713aSLionel Sambuc   if (Self.CompareReferenceRelationship(SrcExpr->getLocStart(),
1124f4a2713aSLionel Sambuc                                         ToType, FromType,
1125f4a2713aSLionel Sambuc                                         DerivedToBase, ObjCConversion,
1126f4a2713aSLionel Sambuc                                         ObjCLifetimeConversion)
1127f4a2713aSLionel Sambuc         < Sema::Ref_Compatible_With_Added_Qualification) {
1128f4a2713aSLionel Sambuc     msg = diag::err_bad_lvalue_to_rvalue_cast;
1129f4a2713aSLionel Sambuc     return TC_Failed;
1130f4a2713aSLionel Sambuc   }
1131f4a2713aSLionel Sambuc 
1132f4a2713aSLionel Sambuc   if (DerivedToBase) {
1133f4a2713aSLionel Sambuc     Kind = CK_DerivedToBase;
1134f4a2713aSLionel Sambuc     CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1135f4a2713aSLionel Sambuc                        /*DetectVirtual=*/true);
1136f4a2713aSLionel Sambuc     if (!Self.IsDerivedFrom(SrcExpr->getType(), R->getPointeeType(), Paths))
1137f4a2713aSLionel Sambuc       return TC_NotApplicable;
1138f4a2713aSLionel Sambuc 
1139f4a2713aSLionel Sambuc     Self.BuildBasePathArray(Paths, BasePath);
1140f4a2713aSLionel Sambuc   } else
1141f4a2713aSLionel Sambuc     Kind = CK_NoOp;
1142f4a2713aSLionel Sambuc 
1143f4a2713aSLionel Sambuc   return TC_Success;
1144f4a2713aSLionel Sambuc }
1145f4a2713aSLionel Sambuc 
1146f4a2713aSLionel Sambuc /// Tests whether a conversion according to C++ 5.2.9p5 is valid.
1147f4a2713aSLionel Sambuc TryCastResult
TryStaticReferenceDowncast(Sema & Self,Expr * SrcExpr,QualType DestType,bool CStyle,const SourceRange & OpRange,unsigned & msg,CastKind & Kind,CXXCastPath & BasePath)1148f4a2713aSLionel Sambuc TryStaticReferenceDowncast(Sema &Self, Expr *SrcExpr, QualType DestType,
1149f4a2713aSLionel Sambuc                            bool CStyle, const SourceRange &OpRange,
1150f4a2713aSLionel Sambuc                            unsigned &msg, CastKind &Kind,
1151f4a2713aSLionel Sambuc                            CXXCastPath &BasePath) {
1152f4a2713aSLionel Sambuc   // C++ 5.2.9p5: An lvalue of type "cv1 B", where B is a class type, can be
1153f4a2713aSLionel Sambuc   //   cast to type "reference to cv2 D", where D is a class derived from B,
1154f4a2713aSLionel Sambuc   //   if a valid standard conversion from "pointer to D" to "pointer to B"
1155f4a2713aSLionel Sambuc   //   exists, cv2 >= cv1, and B is not a virtual base class of D.
1156f4a2713aSLionel Sambuc   // In addition, DR54 clarifies that the base must be accessible in the
1157f4a2713aSLionel Sambuc   // current context. Although the wording of DR54 only applies to the pointer
1158f4a2713aSLionel Sambuc   // variant of this rule, the intent is clearly for it to apply to the this
1159f4a2713aSLionel Sambuc   // conversion as well.
1160f4a2713aSLionel Sambuc 
1161f4a2713aSLionel Sambuc   const ReferenceType *DestReference = DestType->getAs<ReferenceType>();
1162f4a2713aSLionel Sambuc   if (!DestReference) {
1163f4a2713aSLionel Sambuc     return TC_NotApplicable;
1164f4a2713aSLionel Sambuc   }
1165f4a2713aSLionel Sambuc   bool RValueRef = DestReference->isRValueReferenceType();
1166f4a2713aSLionel Sambuc   if (!RValueRef && !SrcExpr->isLValue()) {
1167f4a2713aSLionel Sambuc     // We know the left side is an lvalue reference, so we can suggest a reason.
1168f4a2713aSLionel Sambuc     msg = diag::err_bad_cxx_cast_rvalue;
1169f4a2713aSLionel Sambuc     return TC_NotApplicable;
1170f4a2713aSLionel Sambuc   }
1171f4a2713aSLionel Sambuc 
1172f4a2713aSLionel Sambuc   QualType DestPointee = DestReference->getPointeeType();
1173f4a2713aSLionel Sambuc 
1174*0a6a1f1dSLionel Sambuc   // FIXME: If the source is a prvalue, we should issue a warning (because the
1175*0a6a1f1dSLionel Sambuc   // cast always has undefined behavior), and for AST consistency, we should
1176*0a6a1f1dSLionel Sambuc   // materialize a temporary.
1177f4a2713aSLionel Sambuc   return TryStaticDowncast(Self,
1178f4a2713aSLionel Sambuc                            Self.Context.getCanonicalType(SrcExpr->getType()),
1179f4a2713aSLionel Sambuc                            Self.Context.getCanonicalType(DestPointee), CStyle,
1180f4a2713aSLionel Sambuc                            OpRange, SrcExpr->getType(), DestType, msg, Kind,
1181f4a2713aSLionel Sambuc                            BasePath);
1182f4a2713aSLionel Sambuc }
1183f4a2713aSLionel Sambuc 
1184f4a2713aSLionel Sambuc /// Tests whether a conversion according to C++ 5.2.9p8 is valid.
1185f4a2713aSLionel Sambuc TryCastResult
TryStaticPointerDowncast(Sema & Self,QualType SrcType,QualType DestType,bool CStyle,const SourceRange & OpRange,unsigned & msg,CastKind & Kind,CXXCastPath & BasePath)1186f4a2713aSLionel Sambuc TryStaticPointerDowncast(Sema &Self, QualType SrcType, QualType DestType,
1187f4a2713aSLionel Sambuc                          bool CStyle, const SourceRange &OpRange,
1188f4a2713aSLionel Sambuc                          unsigned &msg, CastKind &Kind,
1189f4a2713aSLionel Sambuc                          CXXCastPath &BasePath) {
1190f4a2713aSLionel Sambuc   // C++ 5.2.9p8: An rvalue of type "pointer to cv1 B", where B is a class
1191f4a2713aSLionel Sambuc   //   type, can be converted to an rvalue of type "pointer to cv2 D", where D
1192f4a2713aSLionel Sambuc   //   is a class derived from B, if a valid standard conversion from "pointer
1193f4a2713aSLionel Sambuc   //   to D" to "pointer to B" exists, cv2 >= cv1, and B is not a virtual base
1194f4a2713aSLionel Sambuc   //   class of D.
1195f4a2713aSLionel Sambuc   // In addition, DR54 clarifies that the base must be accessible in the
1196f4a2713aSLionel Sambuc   // current context.
1197f4a2713aSLionel Sambuc 
1198f4a2713aSLionel Sambuc   const PointerType *DestPointer = DestType->getAs<PointerType>();
1199f4a2713aSLionel Sambuc   if (!DestPointer) {
1200f4a2713aSLionel Sambuc     return TC_NotApplicable;
1201f4a2713aSLionel Sambuc   }
1202f4a2713aSLionel Sambuc 
1203f4a2713aSLionel Sambuc   const PointerType *SrcPointer = SrcType->getAs<PointerType>();
1204f4a2713aSLionel Sambuc   if (!SrcPointer) {
1205f4a2713aSLionel Sambuc     msg = diag::err_bad_static_cast_pointer_nonpointer;
1206f4a2713aSLionel Sambuc     return TC_NotApplicable;
1207f4a2713aSLionel Sambuc   }
1208f4a2713aSLionel Sambuc 
1209f4a2713aSLionel Sambuc   return TryStaticDowncast(Self,
1210f4a2713aSLionel Sambuc                    Self.Context.getCanonicalType(SrcPointer->getPointeeType()),
1211f4a2713aSLionel Sambuc                   Self.Context.getCanonicalType(DestPointer->getPointeeType()),
1212f4a2713aSLionel Sambuc                            CStyle, OpRange, SrcType, DestType, msg, Kind,
1213f4a2713aSLionel Sambuc                            BasePath);
1214f4a2713aSLionel Sambuc }
1215f4a2713aSLionel Sambuc 
1216f4a2713aSLionel Sambuc /// TryStaticDowncast - Common functionality of TryStaticReferenceDowncast and
1217f4a2713aSLionel Sambuc /// TryStaticPointerDowncast. Tests whether a static downcast from SrcType to
1218f4a2713aSLionel Sambuc /// DestType is possible and allowed.
1219f4a2713aSLionel Sambuc TryCastResult
TryStaticDowncast(Sema & Self,CanQualType SrcType,CanQualType DestType,bool CStyle,const SourceRange & OpRange,QualType OrigSrcType,QualType OrigDestType,unsigned & msg,CastKind & Kind,CXXCastPath & BasePath)1220f4a2713aSLionel Sambuc TryStaticDowncast(Sema &Self, CanQualType SrcType, CanQualType DestType,
1221f4a2713aSLionel Sambuc                   bool CStyle, const SourceRange &OpRange, QualType OrigSrcType,
1222f4a2713aSLionel Sambuc                   QualType OrigDestType, unsigned &msg,
1223f4a2713aSLionel Sambuc                   CastKind &Kind, CXXCastPath &BasePath) {
1224f4a2713aSLionel Sambuc   // We can only work with complete types. But don't complain if it doesn't work
1225f4a2713aSLionel Sambuc   if (Self.RequireCompleteType(OpRange.getBegin(), SrcType, 0) ||
1226f4a2713aSLionel Sambuc       Self.RequireCompleteType(OpRange.getBegin(), DestType, 0))
1227f4a2713aSLionel Sambuc     return TC_NotApplicable;
1228f4a2713aSLionel Sambuc 
1229f4a2713aSLionel Sambuc   // Downcast can only happen in class hierarchies, so we need classes.
1230f4a2713aSLionel Sambuc   if (!DestType->getAs<RecordType>() || !SrcType->getAs<RecordType>()) {
1231f4a2713aSLionel Sambuc     return TC_NotApplicable;
1232f4a2713aSLionel Sambuc   }
1233f4a2713aSLionel Sambuc 
1234f4a2713aSLionel Sambuc   CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1235f4a2713aSLionel Sambuc                      /*DetectVirtual=*/true);
1236f4a2713aSLionel Sambuc   if (!Self.IsDerivedFrom(DestType, SrcType, Paths)) {
1237f4a2713aSLionel Sambuc     return TC_NotApplicable;
1238f4a2713aSLionel Sambuc   }
1239f4a2713aSLionel Sambuc 
1240f4a2713aSLionel Sambuc   // Target type does derive from source type. Now we're serious. If an error
1241f4a2713aSLionel Sambuc   // appears now, it's not ignored.
1242f4a2713aSLionel Sambuc   // This may not be entirely in line with the standard. Take for example:
1243f4a2713aSLionel Sambuc   // struct A {};
1244f4a2713aSLionel Sambuc   // struct B : virtual A {
1245f4a2713aSLionel Sambuc   //   B(A&);
1246f4a2713aSLionel Sambuc   // };
1247f4a2713aSLionel Sambuc   //
1248f4a2713aSLionel Sambuc   // void f()
1249f4a2713aSLionel Sambuc   // {
1250f4a2713aSLionel Sambuc   //   (void)static_cast<const B&>(*((A*)0));
1251f4a2713aSLionel Sambuc   // }
1252f4a2713aSLionel Sambuc   // As far as the standard is concerned, p5 does not apply (A is virtual), so
1253f4a2713aSLionel Sambuc   // p2 should be used instead - "const B& t(*((A*)0));" is perfectly valid.
1254f4a2713aSLionel Sambuc   // However, both GCC and Comeau reject this example, and accepting it would
1255f4a2713aSLionel Sambuc   // mean more complex code if we're to preserve the nice error message.
1256f4a2713aSLionel Sambuc   // FIXME: Being 100% compliant here would be nice to have.
1257f4a2713aSLionel Sambuc 
1258f4a2713aSLionel Sambuc   // Must preserve cv, as always, unless we're in C-style mode.
1259f4a2713aSLionel Sambuc   if (!CStyle && !DestType.isAtLeastAsQualifiedAs(SrcType)) {
1260f4a2713aSLionel Sambuc     msg = diag::err_bad_cxx_cast_qualifiers_away;
1261f4a2713aSLionel Sambuc     return TC_Failed;
1262f4a2713aSLionel Sambuc   }
1263f4a2713aSLionel Sambuc 
1264f4a2713aSLionel Sambuc   if (Paths.isAmbiguous(SrcType.getUnqualifiedType())) {
1265f4a2713aSLionel Sambuc     // This code is analoguous to that in CheckDerivedToBaseConversion, except
1266f4a2713aSLionel Sambuc     // that it builds the paths in reverse order.
1267f4a2713aSLionel Sambuc     // To sum up: record all paths to the base and build a nice string from
1268f4a2713aSLionel Sambuc     // them. Use it to spice up the error message.
1269f4a2713aSLionel Sambuc     if (!Paths.isRecordingPaths()) {
1270f4a2713aSLionel Sambuc       Paths.clear();
1271f4a2713aSLionel Sambuc       Paths.setRecordingPaths(true);
1272f4a2713aSLionel Sambuc       Self.IsDerivedFrom(DestType, SrcType, Paths);
1273f4a2713aSLionel Sambuc     }
1274f4a2713aSLionel Sambuc     std::string PathDisplayStr;
1275f4a2713aSLionel Sambuc     std::set<unsigned> DisplayedPaths;
1276f4a2713aSLionel Sambuc     for (CXXBasePaths::paths_iterator PI = Paths.begin(), PE = Paths.end();
1277f4a2713aSLionel Sambuc          PI != PE; ++PI) {
1278f4a2713aSLionel Sambuc       if (DisplayedPaths.insert(PI->back().SubobjectNumber).second) {
1279f4a2713aSLionel Sambuc         // We haven't displayed a path to this particular base
1280f4a2713aSLionel Sambuc         // class subobject yet.
1281f4a2713aSLionel Sambuc         PathDisplayStr += "\n    ";
1282f4a2713aSLionel Sambuc         for (CXXBasePath::const_reverse_iterator EI = PI->rbegin(),
1283f4a2713aSLionel Sambuc                                                  EE = PI->rend();
1284f4a2713aSLionel Sambuc              EI != EE; ++EI)
1285f4a2713aSLionel Sambuc           PathDisplayStr += EI->Base->getType().getAsString() + " -> ";
1286f4a2713aSLionel Sambuc         PathDisplayStr += QualType(DestType).getAsString();
1287f4a2713aSLionel Sambuc       }
1288f4a2713aSLionel Sambuc     }
1289f4a2713aSLionel Sambuc 
1290f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_ambiguous_base_to_derived_cast)
1291f4a2713aSLionel Sambuc       << QualType(SrcType).getUnqualifiedType()
1292f4a2713aSLionel Sambuc       << QualType(DestType).getUnqualifiedType()
1293f4a2713aSLionel Sambuc       << PathDisplayStr << OpRange;
1294f4a2713aSLionel Sambuc     msg = 0;
1295f4a2713aSLionel Sambuc     return TC_Failed;
1296f4a2713aSLionel Sambuc   }
1297f4a2713aSLionel Sambuc 
1298*0a6a1f1dSLionel Sambuc   if (Paths.getDetectedVirtual() != nullptr) {
1299f4a2713aSLionel Sambuc     QualType VirtualBase(Paths.getDetectedVirtual(), 0);
1300f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_static_downcast_via_virtual)
1301f4a2713aSLionel Sambuc       << OrigSrcType << OrigDestType << VirtualBase << OpRange;
1302f4a2713aSLionel Sambuc     msg = 0;
1303f4a2713aSLionel Sambuc     return TC_Failed;
1304f4a2713aSLionel Sambuc   }
1305f4a2713aSLionel Sambuc 
1306f4a2713aSLionel Sambuc   if (!CStyle) {
1307f4a2713aSLionel Sambuc     switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1308f4a2713aSLionel Sambuc                                       SrcType, DestType,
1309f4a2713aSLionel Sambuc                                       Paths.front(),
1310f4a2713aSLionel Sambuc                                 diag::err_downcast_from_inaccessible_base)) {
1311f4a2713aSLionel Sambuc     case Sema::AR_accessible:
1312f4a2713aSLionel Sambuc     case Sema::AR_delayed:     // be optimistic
1313f4a2713aSLionel Sambuc     case Sema::AR_dependent:   // be optimistic
1314f4a2713aSLionel Sambuc       break;
1315f4a2713aSLionel Sambuc 
1316f4a2713aSLionel Sambuc     case Sema::AR_inaccessible:
1317f4a2713aSLionel Sambuc       msg = 0;
1318f4a2713aSLionel Sambuc       return TC_Failed;
1319f4a2713aSLionel Sambuc     }
1320f4a2713aSLionel Sambuc   }
1321f4a2713aSLionel Sambuc 
1322f4a2713aSLionel Sambuc   Self.BuildBasePathArray(Paths, BasePath);
1323f4a2713aSLionel Sambuc   Kind = CK_BaseToDerived;
1324f4a2713aSLionel Sambuc   return TC_Success;
1325f4a2713aSLionel Sambuc }
1326f4a2713aSLionel Sambuc 
1327f4a2713aSLionel Sambuc /// TryStaticMemberPointerUpcast - Tests whether a conversion according to
1328f4a2713aSLionel Sambuc /// C++ 5.2.9p9 is valid:
1329f4a2713aSLionel Sambuc ///
1330f4a2713aSLionel Sambuc ///   An rvalue of type "pointer to member of D of type cv1 T" can be
1331f4a2713aSLionel Sambuc ///   converted to an rvalue of type "pointer to member of B of type cv2 T",
1332f4a2713aSLionel Sambuc ///   where B is a base class of D [...].
1333f4a2713aSLionel Sambuc ///
1334f4a2713aSLionel Sambuc TryCastResult
TryStaticMemberPointerUpcast(Sema & Self,ExprResult & SrcExpr,QualType SrcType,QualType DestType,bool CStyle,const SourceRange & OpRange,unsigned & msg,CastKind & Kind,CXXCastPath & BasePath)1335f4a2713aSLionel Sambuc TryStaticMemberPointerUpcast(Sema &Self, ExprResult &SrcExpr, QualType SrcType,
1336f4a2713aSLionel Sambuc                              QualType DestType, bool CStyle,
1337f4a2713aSLionel Sambuc                              const SourceRange &OpRange,
1338f4a2713aSLionel Sambuc                              unsigned &msg, CastKind &Kind,
1339f4a2713aSLionel Sambuc                              CXXCastPath &BasePath) {
1340f4a2713aSLionel Sambuc   const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>();
1341f4a2713aSLionel Sambuc   if (!DestMemPtr)
1342f4a2713aSLionel Sambuc     return TC_NotApplicable;
1343f4a2713aSLionel Sambuc 
1344f4a2713aSLionel Sambuc   bool WasOverloadedFunction = false;
1345f4a2713aSLionel Sambuc   DeclAccessPair FoundOverload;
1346f4a2713aSLionel Sambuc   if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
1347f4a2713aSLionel Sambuc     if (FunctionDecl *Fn
1348f4a2713aSLionel Sambuc           = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(), DestType, false,
1349f4a2713aSLionel Sambuc                                                     FoundOverload)) {
1350f4a2713aSLionel Sambuc       CXXMethodDecl *M = cast<CXXMethodDecl>(Fn);
1351f4a2713aSLionel Sambuc       SrcType = Self.Context.getMemberPointerType(Fn->getType(),
1352f4a2713aSLionel Sambuc                       Self.Context.getTypeDeclType(M->getParent()).getTypePtr());
1353f4a2713aSLionel Sambuc       WasOverloadedFunction = true;
1354f4a2713aSLionel Sambuc     }
1355f4a2713aSLionel Sambuc   }
1356f4a2713aSLionel Sambuc 
1357f4a2713aSLionel Sambuc   const MemberPointerType *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1358f4a2713aSLionel Sambuc   if (!SrcMemPtr) {
1359f4a2713aSLionel Sambuc     msg = diag::err_bad_static_cast_member_pointer_nonmp;
1360f4a2713aSLionel Sambuc     return TC_NotApplicable;
1361f4a2713aSLionel Sambuc   }
1362f4a2713aSLionel Sambuc 
1363f4a2713aSLionel Sambuc   // T == T, modulo cv
1364f4a2713aSLionel Sambuc   if (!Self.Context.hasSameUnqualifiedType(SrcMemPtr->getPointeeType(),
1365f4a2713aSLionel Sambuc                                            DestMemPtr->getPointeeType()))
1366f4a2713aSLionel Sambuc     return TC_NotApplicable;
1367f4a2713aSLionel Sambuc 
1368f4a2713aSLionel Sambuc   // B base of D
1369f4a2713aSLionel Sambuc   QualType SrcClass(SrcMemPtr->getClass(), 0);
1370f4a2713aSLionel Sambuc   QualType DestClass(DestMemPtr->getClass(), 0);
1371f4a2713aSLionel Sambuc   CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
1372f4a2713aSLionel Sambuc                   /*DetectVirtual=*/true);
1373*0a6a1f1dSLionel Sambuc   if (Self.RequireCompleteType(OpRange.getBegin(), SrcClass, 0) ||
1374*0a6a1f1dSLionel Sambuc       !Self.IsDerivedFrom(SrcClass, DestClass, Paths)) {
1375f4a2713aSLionel Sambuc     return TC_NotApplicable;
1376f4a2713aSLionel Sambuc   }
1377f4a2713aSLionel Sambuc 
1378f4a2713aSLionel Sambuc   // B is a base of D. But is it an allowed base? If not, it's a hard error.
1379f4a2713aSLionel Sambuc   if (Paths.isAmbiguous(Self.Context.getCanonicalType(DestClass))) {
1380f4a2713aSLionel Sambuc     Paths.clear();
1381f4a2713aSLionel Sambuc     Paths.setRecordingPaths(true);
1382f4a2713aSLionel Sambuc     bool StillOkay = Self.IsDerivedFrom(SrcClass, DestClass, Paths);
1383f4a2713aSLionel Sambuc     assert(StillOkay);
1384f4a2713aSLionel Sambuc     (void)StillOkay;
1385f4a2713aSLionel Sambuc     std::string PathDisplayStr = Self.getAmbiguousPathsDisplayString(Paths);
1386f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_ambiguous_memptr_conv)
1387f4a2713aSLionel Sambuc       << 1 << SrcClass << DestClass << PathDisplayStr << OpRange;
1388f4a2713aSLionel Sambuc     msg = 0;
1389f4a2713aSLionel Sambuc     return TC_Failed;
1390f4a2713aSLionel Sambuc   }
1391f4a2713aSLionel Sambuc 
1392f4a2713aSLionel Sambuc   if (const RecordType *VBase = Paths.getDetectedVirtual()) {
1393f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_memptr_conv_via_virtual)
1394f4a2713aSLionel Sambuc       << SrcClass << DestClass << QualType(VBase, 0) << OpRange;
1395f4a2713aSLionel Sambuc     msg = 0;
1396f4a2713aSLionel Sambuc     return TC_Failed;
1397f4a2713aSLionel Sambuc   }
1398f4a2713aSLionel Sambuc 
1399f4a2713aSLionel Sambuc   if (!CStyle) {
1400f4a2713aSLionel Sambuc     switch (Self.CheckBaseClassAccess(OpRange.getBegin(),
1401f4a2713aSLionel Sambuc                                       DestClass, SrcClass,
1402f4a2713aSLionel Sambuc                                       Paths.front(),
1403f4a2713aSLionel Sambuc                                       diag::err_upcast_to_inaccessible_base)) {
1404f4a2713aSLionel Sambuc     case Sema::AR_accessible:
1405f4a2713aSLionel Sambuc     case Sema::AR_delayed:
1406f4a2713aSLionel Sambuc     case Sema::AR_dependent:
1407f4a2713aSLionel Sambuc       // Optimistically assume that the delayed and dependent cases
1408f4a2713aSLionel Sambuc       // will work out.
1409f4a2713aSLionel Sambuc       break;
1410f4a2713aSLionel Sambuc 
1411f4a2713aSLionel Sambuc     case Sema::AR_inaccessible:
1412f4a2713aSLionel Sambuc       msg = 0;
1413f4a2713aSLionel Sambuc       return TC_Failed;
1414f4a2713aSLionel Sambuc     }
1415f4a2713aSLionel Sambuc   }
1416f4a2713aSLionel Sambuc 
1417f4a2713aSLionel Sambuc   if (WasOverloadedFunction) {
1418f4a2713aSLionel Sambuc     // Resolve the address of the overloaded function again, this time
1419f4a2713aSLionel Sambuc     // allowing complaints if something goes wrong.
1420f4a2713aSLionel Sambuc     FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
1421f4a2713aSLionel Sambuc                                                                DestType,
1422f4a2713aSLionel Sambuc                                                                true,
1423f4a2713aSLionel Sambuc                                                                FoundOverload);
1424f4a2713aSLionel Sambuc     if (!Fn) {
1425f4a2713aSLionel Sambuc       msg = 0;
1426f4a2713aSLionel Sambuc       return TC_Failed;
1427f4a2713aSLionel Sambuc     }
1428f4a2713aSLionel Sambuc 
1429f4a2713aSLionel Sambuc     SrcExpr = Self.FixOverloadedFunctionReference(SrcExpr, FoundOverload, Fn);
1430f4a2713aSLionel Sambuc     if (!SrcExpr.isUsable()) {
1431f4a2713aSLionel Sambuc       msg = 0;
1432f4a2713aSLionel Sambuc       return TC_Failed;
1433f4a2713aSLionel Sambuc     }
1434f4a2713aSLionel Sambuc   }
1435f4a2713aSLionel Sambuc 
1436f4a2713aSLionel Sambuc   Self.BuildBasePathArray(Paths, BasePath);
1437f4a2713aSLionel Sambuc   Kind = CK_DerivedToBaseMemberPointer;
1438f4a2713aSLionel Sambuc   return TC_Success;
1439f4a2713aSLionel Sambuc }
1440f4a2713aSLionel Sambuc 
1441f4a2713aSLionel Sambuc /// TryStaticImplicitCast - Tests whether a conversion according to C++ 5.2.9p2
1442f4a2713aSLionel Sambuc /// is valid:
1443f4a2713aSLionel Sambuc ///
1444f4a2713aSLionel Sambuc ///   An expression e can be explicitly converted to a type T using a
1445f4a2713aSLionel Sambuc ///   @c static_cast if the declaration "T t(e);" is well-formed [...].
1446f4a2713aSLionel Sambuc TryCastResult
TryStaticImplicitCast(Sema & Self,ExprResult & SrcExpr,QualType DestType,Sema::CheckedConversionKind CCK,const SourceRange & OpRange,unsigned & msg,CastKind & Kind,bool ListInitialization)1447f4a2713aSLionel Sambuc TryStaticImplicitCast(Sema &Self, ExprResult &SrcExpr, QualType DestType,
1448f4a2713aSLionel Sambuc                       Sema::CheckedConversionKind CCK,
1449f4a2713aSLionel Sambuc                       const SourceRange &OpRange, unsigned &msg,
1450f4a2713aSLionel Sambuc                       CastKind &Kind, bool ListInitialization) {
1451f4a2713aSLionel Sambuc   if (DestType->isRecordType()) {
1452f4a2713aSLionel Sambuc     if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
1453f4a2713aSLionel Sambuc                                  diag::err_bad_dynamic_cast_incomplete) ||
1454f4a2713aSLionel Sambuc         Self.RequireNonAbstractType(OpRange.getBegin(), DestType,
1455f4a2713aSLionel Sambuc                                     diag::err_allocation_of_abstract_type)) {
1456f4a2713aSLionel Sambuc       msg = 0;
1457f4a2713aSLionel Sambuc       return TC_Failed;
1458f4a2713aSLionel Sambuc     }
1459*0a6a1f1dSLionel Sambuc   } else if (DestType->isMemberPointerType()) {
1460*0a6a1f1dSLionel Sambuc     if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1461*0a6a1f1dSLionel Sambuc       Self.RequireCompleteType(OpRange.getBegin(), DestType, 0);
1462*0a6a1f1dSLionel Sambuc     }
1463f4a2713aSLionel Sambuc   }
1464f4a2713aSLionel Sambuc 
1465f4a2713aSLionel Sambuc   InitializedEntity Entity = InitializedEntity::InitializeTemporary(DestType);
1466f4a2713aSLionel Sambuc   InitializationKind InitKind
1467f4a2713aSLionel Sambuc     = (CCK == Sema::CCK_CStyleCast)
1468f4a2713aSLionel Sambuc         ? InitializationKind::CreateCStyleCast(OpRange.getBegin(), OpRange,
1469f4a2713aSLionel Sambuc                                                ListInitialization)
1470f4a2713aSLionel Sambuc     : (CCK == Sema::CCK_FunctionalCast)
1471f4a2713aSLionel Sambuc         ? InitializationKind::CreateFunctionalCast(OpRange, ListInitialization)
1472f4a2713aSLionel Sambuc     : InitializationKind::CreateCast(OpRange);
1473f4a2713aSLionel Sambuc   Expr *SrcExprRaw = SrcExpr.get();
1474f4a2713aSLionel Sambuc   InitializationSequence InitSeq(Self, Entity, InitKind, SrcExprRaw);
1475f4a2713aSLionel Sambuc 
1476f4a2713aSLionel Sambuc   // At this point of CheckStaticCast, if the destination is a reference,
1477f4a2713aSLionel Sambuc   // or the expression is an overload expression this has to work.
1478f4a2713aSLionel Sambuc   // There is no other way that works.
1479f4a2713aSLionel Sambuc   // On the other hand, if we're checking a C-style cast, we've still got
1480f4a2713aSLionel Sambuc   // the reinterpret_cast way.
1481f4a2713aSLionel Sambuc   bool CStyle
1482f4a2713aSLionel Sambuc     = (CCK == Sema::CCK_CStyleCast || CCK == Sema::CCK_FunctionalCast);
1483f4a2713aSLionel Sambuc   if (InitSeq.Failed() && (CStyle || !DestType->isReferenceType()))
1484f4a2713aSLionel Sambuc     return TC_NotApplicable;
1485f4a2713aSLionel Sambuc 
1486f4a2713aSLionel Sambuc   ExprResult Result = InitSeq.Perform(Self, Entity, InitKind, SrcExprRaw);
1487f4a2713aSLionel Sambuc   if (Result.isInvalid()) {
1488f4a2713aSLionel Sambuc     msg = 0;
1489f4a2713aSLionel Sambuc     return TC_Failed;
1490f4a2713aSLionel Sambuc   }
1491f4a2713aSLionel Sambuc 
1492f4a2713aSLionel Sambuc   if (InitSeq.isConstructorInitialization())
1493f4a2713aSLionel Sambuc     Kind = CK_ConstructorConversion;
1494f4a2713aSLionel Sambuc   else
1495f4a2713aSLionel Sambuc     Kind = CK_NoOp;
1496f4a2713aSLionel Sambuc 
1497f4a2713aSLionel Sambuc   SrcExpr = Result;
1498f4a2713aSLionel Sambuc   return TC_Success;
1499f4a2713aSLionel Sambuc }
1500f4a2713aSLionel Sambuc 
1501f4a2713aSLionel Sambuc /// TryConstCast - See if a const_cast from source to destination is allowed,
1502f4a2713aSLionel Sambuc /// and perform it if it is.
TryConstCast(Sema & Self,ExprResult & SrcExpr,QualType DestType,bool CStyle,unsigned & msg)1503f4a2713aSLionel Sambuc static TryCastResult TryConstCast(Sema &Self, ExprResult &SrcExpr,
1504f4a2713aSLionel Sambuc                                   QualType DestType, bool CStyle,
1505f4a2713aSLionel Sambuc                                   unsigned &msg) {
1506f4a2713aSLionel Sambuc   DestType = Self.Context.getCanonicalType(DestType);
1507f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr.get()->getType();
1508f4a2713aSLionel Sambuc   bool NeedToMaterializeTemporary = false;
1509f4a2713aSLionel Sambuc 
1510f4a2713aSLionel Sambuc   if (const ReferenceType *DestTypeTmp =DestType->getAs<ReferenceType>()) {
1511f4a2713aSLionel Sambuc     // C++11 5.2.11p4:
1512f4a2713aSLionel Sambuc     //   if a pointer to T1 can be explicitly converted to the type "pointer to
1513f4a2713aSLionel Sambuc     //   T2" using a const_cast, then the following conversions can also be
1514f4a2713aSLionel Sambuc     //   made:
1515f4a2713aSLionel Sambuc     //    -- an lvalue of type T1 can be explicitly converted to an lvalue of
1516f4a2713aSLionel Sambuc     //       type T2 using the cast const_cast<T2&>;
1517f4a2713aSLionel Sambuc     //    -- a glvalue of type T1 can be explicitly converted to an xvalue of
1518f4a2713aSLionel Sambuc     //       type T2 using the cast const_cast<T2&&>; and
1519f4a2713aSLionel Sambuc     //    -- if T1 is a class type, a prvalue of type T1 can be explicitly
1520f4a2713aSLionel Sambuc     //       converted to an xvalue of type T2 using the cast const_cast<T2&&>.
1521f4a2713aSLionel Sambuc 
1522f4a2713aSLionel Sambuc     if (isa<LValueReferenceType>(DestTypeTmp) && !SrcExpr.get()->isLValue()) {
1523f4a2713aSLionel Sambuc       // Cannot const_cast non-lvalue to lvalue reference type. But if this
1524f4a2713aSLionel Sambuc       // is C-style, static_cast might find a way, so we simply suggest a
1525f4a2713aSLionel Sambuc       // message and tell the parent to keep searching.
1526f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_rvalue;
1527f4a2713aSLionel Sambuc       return TC_NotApplicable;
1528f4a2713aSLionel Sambuc     }
1529f4a2713aSLionel Sambuc 
1530f4a2713aSLionel Sambuc     if (isa<RValueReferenceType>(DestTypeTmp) && SrcExpr.get()->isRValue()) {
1531f4a2713aSLionel Sambuc       if (!SrcType->isRecordType()) {
1532f4a2713aSLionel Sambuc         // Cannot const_cast non-class prvalue to rvalue reference type. But if
1533f4a2713aSLionel Sambuc         // this is C-style, static_cast can do this.
1534f4a2713aSLionel Sambuc         msg = diag::err_bad_cxx_cast_rvalue;
1535f4a2713aSLionel Sambuc         return TC_NotApplicable;
1536f4a2713aSLionel Sambuc       }
1537f4a2713aSLionel Sambuc 
1538f4a2713aSLionel Sambuc       // Materialize the class prvalue so that the const_cast can bind a
1539f4a2713aSLionel Sambuc       // reference to it.
1540f4a2713aSLionel Sambuc       NeedToMaterializeTemporary = true;
1541f4a2713aSLionel Sambuc     }
1542f4a2713aSLionel Sambuc 
1543f4a2713aSLionel Sambuc     // It's not completely clear under the standard whether we can
1544f4a2713aSLionel Sambuc     // const_cast bit-field gl-values.  Doing so would not be
1545f4a2713aSLionel Sambuc     // intrinsically complicated, but for now, we say no for
1546f4a2713aSLionel Sambuc     // consistency with other compilers and await the word of the
1547f4a2713aSLionel Sambuc     // committee.
1548f4a2713aSLionel Sambuc     if (SrcExpr.get()->refersToBitField()) {
1549f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_bitfield;
1550f4a2713aSLionel Sambuc       return TC_NotApplicable;
1551f4a2713aSLionel Sambuc     }
1552f4a2713aSLionel Sambuc 
1553f4a2713aSLionel Sambuc     DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1554f4a2713aSLionel Sambuc     SrcType = Self.Context.getPointerType(SrcType);
1555f4a2713aSLionel Sambuc   }
1556f4a2713aSLionel Sambuc 
1557f4a2713aSLionel Sambuc   // C++ 5.2.11p5: For a const_cast involving pointers to data members [...]
1558f4a2713aSLionel Sambuc   //   the rules for const_cast are the same as those used for pointers.
1559f4a2713aSLionel Sambuc 
1560f4a2713aSLionel Sambuc   if (!DestType->isPointerType() &&
1561f4a2713aSLionel Sambuc       !DestType->isMemberPointerType() &&
1562f4a2713aSLionel Sambuc       !DestType->isObjCObjectPointerType()) {
1563f4a2713aSLionel Sambuc     // Cannot cast to non-pointer, non-reference type. Note that, if DestType
1564f4a2713aSLionel Sambuc     // was a reference type, we converted it to a pointer above.
1565f4a2713aSLionel Sambuc     // The status of rvalue references isn't entirely clear, but it looks like
1566f4a2713aSLionel Sambuc     // conversion to them is simply invalid.
1567f4a2713aSLionel Sambuc     // C++ 5.2.11p3: For two pointer types [...]
1568f4a2713aSLionel Sambuc     if (!CStyle)
1569f4a2713aSLionel Sambuc       msg = diag::err_bad_const_cast_dest;
1570f4a2713aSLionel Sambuc     return TC_NotApplicable;
1571f4a2713aSLionel Sambuc   }
1572f4a2713aSLionel Sambuc   if (DestType->isFunctionPointerType() ||
1573f4a2713aSLionel Sambuc       DestType->isMemberFunctionPointerType()) {
1574f4a2713aSLionel Sambuc     // Cannot cast direct function pointers.
1575f4a2713aSLionel Sambuc     // C++ 5.2.11p2: [...] where T is any object type or the void type [...]
1576f4a2713aSLionel Sambuc     // T is the ultimate pointee of source and target type.
1577f4a2713aSLionel Sambuc     if (!CStyle)
1578f4a2713aSLionel Sambuc       msg = diag::err_bad_const_cast_dest;
1579f4a2713aSLionel Sambuc     return TC_NotApplicable;
1580f4a2713aSLionel Sambuc   }
1581f4a2713aSLionel Sambuc   SrcType = Self.Context.getCanonicalType(SrcType);
1582f4a2713aSLionel Sambuc 
1583f4a2713aSLionel Sambuc   // Unwrap the pointers. Ignore qualifiers. Terminate early if the types are
1584f4a2713aSLionel Sambuc   // completely equal.
1585f4a2713aSLionel Sambuc   // C++ 5.2.11p3 describes the core semantics of const_cast. All cv specifiers
1586f4a2713aSLionel Sambuc   // in multi-level pointers may change, but the level count must be the same,
1587f4a2713aSLionel Sambuc   // as must be the final pointee type.
1588f4a2713aSLionel Sambuc   while (SrcType != DestType &&
1589f4a2713aSLionel Sambuc          Self.Context.UnwrapSimilarPointerTypes(SrcType, DestType)) {
1590f4a2713aSLionel Sambuc     Qualifiers SrcQuals, DestQuals;
1591f4a2713aSLionel Sambuc     SrcType = Self.Context.getUnqualifiedArrayType(SrcType, SrcQuals);
1592f4a2713aSLionel Sambuc     DestType = Self.Context.getUnqualifiedArrayType(DestType, DestQuals);
1593f4a2713aSLionel Sambuc 
1594f4a2713aSLionel Sambuc     // const_cast is permitted to strip cvr-qualifiers, only. Make sure that
1595f4a2713aSLionel Sambuc     // the other qualifiers (e.g., address spaces) are identical.
1596f4a2713aSLionel Sambuc     SrcQuals.removeCVRQualifiers();
1597f4a2713aSLionel Sambuc     DestQuals.removeCVRQualifiers();
1598f4a2713aSLionel Sambuc     if (SrcQuals != DestQuals)
1599f4a2713aSLionel Sambuc       return TC_NotApplicable;
1600f4a2713aSLionel Sambuc   }
1601f4a2713aSLionel Sambuc 
1602f4a2713aSLionel Sambuc   // Since we're dealing in canonical types, the remainder must be the same.
1603f4a2713aSLionel Sambuc   if (SrcType != DestType)
1604f4a2713aSLionel Sambuc     return TC_NotApplicable;
1605f4a2713aSLionel Sambuc 
1606f4a2713aSLionel Sambuc   if (NeedToMaterializeTemporary)
1607f4a2713aSLionel Sambuc     // This is a const_cast from a class prvalue to an rvalue reference type.
1608f4a2713aSLionel Sambuc     // Materialize a temporary to store the result of the conversion.
1609f4a2713aSLionel Sambuc     SrcExpr = new (Self.Context) MaterializeTemporaryExpr(
1610*0a6a1f1dSLionel Sambuc         SrcType, SrcExpr.get(), /*IsLValueReference*/ false);
1611f4a2713aSLionel Sambuc 
1612f4a2713aSLionel Sambuc   return TC_Success;
1613f4a2713aSLionel Sambuc }
1614f4a2713aSLionel Sambuc 
1615f4a2713aSLionel Sambuc // Checks for undefined behavior in reinterpret_cast.
1616f4a2713aSLionel Sambuc // The cases that is checked for is:
1617f4a2713aSLionel Sambuc // *reinterpret_cast<T*>(&a)
1618f4a2713aSLionel Sambuc // reinterpret_cast<T&>(a)
1619f4a2713aSLionel Sambuc // where accessing 'a' as type 'T' will result in undefined behavior.
CheckCompatibleReinterpretCast(QualType SrcType,QualType DestType,bool IsDereference,SourceRange Range)1620f4a2713aSLionel Sambuc void Sema::CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
1621f4a2713aSLionel Sambuc                                           bool IsDereference,
1622f4a2713aSLionel Sambuc                                           SourceRange Range) {
1623f4a2713aSLionel Sambuc   unsigned DiagID = IsDereference ?
1624f4a2713aSLionel Sambuc                         diag::warn_pointer_indirection_from_incompatible_type :
1625f4a2713aSLionel Sambuc                         diag::warn_undefined_reinterpret_cast;
1626f4a2713aSLionel Sambuc 
1627*0a6a1f1dSLionel Sambuc   if (Diags.isIgnored(DiagID, Range.getBegin()))
1628f4a2713aSLionel Sambuc     return;
1629f4a2713aSLionel Sambuc 
1630f4a2713aSLionel Sambuc   QualType SrcTy, DestTy;
1631f4a2713aSLionel Sambuc   if (IsDereference) {
1632f4a2713aSLionel Sambuc     if (!SrcType->getAs<PointerType>() || !DestType->getAs<PointerType>()) {
1633f4a2713aSLionel Sambuc       return;
1634f4a2713aSLionel Sambuc     }
1635f4a2713aSLionel Sambuc     SrcTy = SrcType->getPointeeType();
1636f4a2713aSLionel Sambuc     DestTy = DestType->getPointeeType();
1637f4a2713aSLionel Sambuc   } else {
1638f4a2713aSLionel Sambuc     if (!DestType->getAs<ReferenceType>()) {
1639f4a2713aSLionel Sambuc       return;
1640f4a2713aSLionel Sambuc     }
1641f4a2713aSLionel Sambuc     SrcTy = SrcType;
1642f4a2713aSLionel Sambuc     DestTy = DestType->getPointeeType();
1643f4a2713aSLionel Sambuc   }
1644f4a2713aSLionel Sambuc 
1645f4a2713aSLionel Sambuc   // Cast is compatible if the types are the same.
1646f4a2713aSLionel Sambuc   if (Context.hasSameUnqualifiedType(DestTy, SrcTy)) {
1647f4a2713aSLionel Sambuc     return;
1648f4a2713aSLionel Sambuc   }
1649f4a2713aSLionel Sambuc   // or one of the types is a char or void type
1650f4a2713aSLionel Sambuc   if (DestTy->isAnyCharacterType() || DestTy->isVoidType() ||
1651f4a2713aSLionel Sambuc       SrcTy->isAnyCharacterType() || SrcTy->isVoidType()) {
1652f4a2713aSLionel Sambuc     return;
1653f4a2713aSLionel Sambuc   }
1654f4a2713aSLionel Sambuc   // or one of the types is a tag type.
1655f4a2713aSLionel Sambuc   if (SrcTy->getAs<TagType>() || DestTy->getAs<TagType>()) {
1656f4a2713aSLionel Sambuc     return;
1657f4a2713aSLionel Sambuc   }
1658f4a2713aSLionel Sambuc 
1659f4a2713aSLionel Sambuc   // FIXME: Scoped enums?
1660f4a2713aSLionel Sambuc   if ((SrcTy->isUnsignedIntegerType() && DestTy->isSignedIntegerType()) ||
1661f4a2713aSLionel Sambuc       (SrcTy->isSignedIntegerType() && DestTy->isUnsignedIntegerType())) {
1662f4a2713aSLionel Sambuc     if (Context.getTypeSize(DestTy) == Context.getTypeSize(SrcTy)) {
1663f4a2713aSLionel Sambuc       return;
1664f4a2713aSLionel Sambuc     }
1665f4a2713aSLionel Sambuc   }
1666f4a2713aSLionel Sambuc 
1667f4a2713aSLionel Sambuc   Diag(Range.getBegin(), DiagID) << SrcType << DestType << Range;
1668f4a2713aSLionel Sambuc }
1669f4a2713aSLionel Sambuc 
DiagnoseCastOfObjCSEL(Sema & Self,const ExprResult & SrcExpr,QualType DestType)1670f4a2713aSLionel Sambuc static void DiagnoseCastOfObjCSEL(Sema &Self, const ExprResult &SrcExpr,
1671f4a2713aSLionel Sambuc                                   QualType DestType) {
1672f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr.get()->getType();
1673f4a2713aSLionel Sambuc   if (Self.Context.hasSameType(SrcType, DestType))
1674f4a2713aSLionel Sambuc     return;
1675f4a2713aSLionel Sambuc   if (const PointerType *SrcPtrTy = SrcType->getAs<PointerType>())
1676f4a2713aSLionel Sambuc     if (SrcPtrTy->isObjCSelType()) {
1677f4a2713aSLionel Sambuc       QualType DT = DestType;
1678f4a2713aSLionel Sambuc       if (isa<PointerType>(DestType))
1679f4a2713aSLionel Sambuc         DT = DestType->getPointeeType();
1680f4a2713aSLionel Sambuc       if (!DT.getUnqualifiedType()->isVoidType())
1681f4a2713aSLionel Sambuc         Self.Diag(SrcExpr.get()->getExprLoc(),
1682f4a2713aSLionel Sambuc                   diag::warn_cast_pointer_from_sel)
1683f4a2713aSLionel Sambuc         << SrcType << DestType << SrcExpr.get()->getSourceRange();
1684f4a2713aSLionel Sambuc     }
1685f4a2713aSLionel Sambuc }
1686f4a2713aSLionel Sambuc 
checkIntToPointerCast(bool CStyle,SourceLocation Loc,const Expr * SrcExpr,QualType DestType,Sema & Self)1687f4a2713aSLionel Sambuc static void checkIntToPointerCast(bool CStyle, SourceLocation Loc,
1688f4a2713aSLionel Sambuc                                   const Expr *SrcExpr, QualType DestType,
1689f4a2713aSLionel Sambuc                                   Sema &Self) {
1690f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr->getType();
1691f4a2713aSLionel Sambuc 
1692f4a2713aSLionel Sambuc   // Not warning on reinterpret_cast, boolean, constant expressions, etc
1693f4a2713aSLionel Sambuc   // are not explicit design choices, but consistent with GCC's behavior.
1694f4a2713aSLionel Sambuc   // Feel free to modify them if you've reason/evidence for an alternative.
1695f4a2713aSLionel Sambuc   if (CStyle && SrcType->isIntegralType(Self.Context)
1696f4a2713aSLionel Sambuc       && !SrcType->isBooleanType()
1697f4a2713aSLionel Sambuc       && !SrcType->isEnumeralType()
1698f4a2713aSLionel Sambuc       && !SrcExpr->isIntegerConstantExpr(Self.Context)
1699f4a2713aSLionel Sambuc       && Self.Context.getTypeSize(DestType) >
1700f4a2713aSLionel Sambuc          Self.Context.getTypeSize(SrcType)) {
1701f4a2713aSLionel Sambuc     // Separate between casts to void* and non-void* pointers.
1702f4a2713aSLionel Sambuc     // Some APIs use (abuse) void* for something like a user context,
1703f4a2713aSLionel Sambuc     // and often that value is an integer even if it isn't a pointer itself.
1704f4a2713aSLionel Sambuc     // Having a separate warning flag allows users to control the warning
1705f4a2713aSLionel Sambuc     // for their workflow.
1706f4a2713aSLionel Sambuc     unsigned Diag = DestType->isVoidPointerType() ?
1707f4a2713aSLionel Sambuc                       diag::warn_int_to_void_pointer_cast
1708f4a2713aSLionel Sambuc                     : diag::warn_int_to_pointer_cast;
1709f4a2713aSLionel Sambuc     Self.Diag(Loc, Diag) << SrcType << DestType;
1710f4a2713aSLionel Sambuc   }
1711f4a2713aSLionel Sambuc }
1712f4a2713aSLionel Sambuc 
TryReinterpretCast(Sema & Self,ExprResult & SrcExpr,QualType DestType,bool CStyle,const SourceRange & OpRange,unsigned & msg,CastKind & Kind)1713f4a2713aSLionel Sambuc static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
1714f4a2713aSLionel Sambuc                                         QualType DestType, bool CStyle,
1715f4a2713aSLionel Sambuc                                         const SourceRange &OpRange,
1716f4a2713aSLionel Sambuc                                         unsigned &msg,
1717f4a2713aSLionel Sambuc                                         CastKind &Kind) {
1718f4a2713aSLionel Sambuc   bool IsLValueCast = false;
1719f4a2713aSLionel Sambuc 
1720f4a2713aSLionel Sambuc   DestType = Self.Context.getCanonicalType(DestType);
1721f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr.get()->getType();
1722f4a2713aSLionel Sambuc 
1723f4a2713aSLionel Sambuc   // Is the source an overloaded name? (i.e. &foo)
1724f4a2713aSLionel Sambuc   // If so, reinterpret_cast can not help us here (13.4, p1, bullet 5) ...
1725f4a2713aSLionel Sambuc   if (SrcType == Self.Context.OverloadTy) {
1726f4a2713aSLionel Sambuc     // ... unless foo<int> resolves to an lvalue unambiguously.
1727f4a2713aSLionel Sambuc     // TODO: what if this fails because of DiagnoseUseOfDecl or something
1728f4a2713aSLionel Sambuc     // like it?
1729f4a2713aSLionel Sambuc     ExprResult SingleFunctionExpr = SrcExpr;
1730f4a2713aSLionel Sambuc     if (Self.ResolveAndFixSingleFunctionTemplateSpecialization(
1731f4a2713aSLionel Sambuc           SingleFunctionExpr,
1732f4a2713aSLionel Sambuc           Expr::getValueKindForType(DestType) == VK_RValue // Convert Fun to Ptr
1733f4a2713aSLionel Sambuc         ) && SingleFunctionExpr.isUsable()) {
1734f4a2713aSLionel Sambuc       SrcExpr = SingleFunctionExpr;
1735f4a2713aSLionel Sambuc       SrcType = SrcExpr.get()->getType();
1736f4a2713aSLionel Sambuc     } else {
1737f4a2713aSLionel Sambuc       return TC_NotApplicable;
1738f4a2713aSLionel Sambuc     }
1739f4a2713aSLionel Sambuc   }
1740f4a2713aSLionel Sambuc 
1741f4a2713aSLionel Sambuc   if (const ReferenceType *DestTypeTmp = DestType->getAs<ReferenceType>()) {
1742f4a2713aSLionel Sambuc     if (!SrcExpr.get()->isGLValue()) {
1743f4a2713aSLionel Sambuc       // Cannot cast non-glvalue to (lvalue or rvalue) reference type. See the
1744f4a2713aSLionel Sambuc       // similar comment in const_cast.
1745f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_rvalue;
1746f4a2713aSLionel Sambuc       return TC_NotApplicable;
1747f4a2713aSLionel Sambuc     }
1748f4a2713aSLionel Sambuc 
1749f4a2713aSLionel Sambuc     if (!CStyle) {
1750f4a2713aSLionel Sambuc       Self.CheckCompatibleReinterpretCast(SrcType, DestType,
1751f4a2713aSLionel Sambuc                                           /*isDereference=*/false, OpRange);
1752f4a2713aSLionel Sambuc     }
1753f4a2713aSLionel Sambuc 
1754f4a2713aSLionel Sambuc     // C++ 5.2.10p10: [...] a reference cast reinterpret_cast<T&>(x) has the
1755f4a2713aSLionel Sambuc     //   same effect as the conversion *reinterpret_cast<T*>(&x) with the
1756f4a2713aSLionel Sambuc     //   built-in & and * operators.
1757f4a2713aSLionel Sambuc 
1758*0a6a1f1dSLionel Sambuc     const char *inappropriate = nullptr;
1759f4a2713aSLionel Sambuc     switch (SrcExpr.get()->getObjectKind()) {
1760f4a2713aSLionel Sambuc     case OK_Ordinary:
1761f4a2713aSLionel Sambuc       break;
1762f4a2713aSLionel Sambuc     case OK_BitField:        inappropriate = "bit-field";           break;
1763f4a2713aSLionel Sambuc     case OK_VectorComponent: inappropriate = "vector element";      break;
1764f4a2713aSLionel Sambuc     case OK_ObjCProperty:    inappropriate = "property expression"; break;
1765f4a2713aSLionel Sambuc     case OK_ObjCSubscript:   inappropriate = "container subscripting expression";
1766f4a2713aSLionel Sambuc                              break;
1767f4a2713aSLionel Sambuc     }
1768f4a2713aSLionel Sambuc     if (inappropriate) {
1769f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
1770f4a2713aSLionel Sambuc           << inappropriate << DestType
1771f4a2713aSLionel Sambuc           << OpRange << SrcExpr.get()->getSourceRange();
1772f4a2713aSLionel Sambuc       msg = 0; SrcExpr = ExprError();
1773f4a2713aSLionel Sambuc       return TC_NotApplicable;
1774f4a2713aSLionel Sambuc     }
1775f4a2713aSLionel Sambuc 
1776f4a2713aSLionel Sambuc     // This code does this transformation for the checked types.
1777f4a2713aSLionel Sambuc     DestType = Self.Context.getPointerType(DestTypeTmp->getPointeeType());
1778f4a2713aSLionel Sambuc     SrcType = Self.Context.getPointerType(SrcType);
1779f4a2713aSLionel Sambuc 
1780f4a2713aSLionel Sambuc     IsLValueCast = true;
1781f4a2713aSLionel Sambuc   }
1782f4a2713aSLionel Sambuc 
1783f4a2713aSLionel Sambuc   // Canonicalize source for comparison.
1784f4a2713aSLionel Sambuc   SrcType = Self.Context.getCanonicalType(SrcType);
1785f4a2713aSLionel Sambuc 
1786f4a2713aSLionel Sambuc   const MemberPointerType *DestMemPtr = DestType->getAs<MemberPointerType>(),
1787f4a2713aSLionel Sambuc                           *SrcMemPtr = SrcType->getAs<MemberPointerType>();
1788f4a2713aSLionel Sambuc   if (DestMemPtr && SrcMemPtr) {
1789f4a2713aSLionel Sambuc     // C++ 5.2.10p9: An rvalue of type "pointer to member of X of type T1"
1790f4a2713aSLionel Sambuc     //   can be explicitly converted to an rvalue of type "pointer to member
1791f4a2713aSLionel Sambuc     //   of Y of type T2" if T1 and T2 are both function types or both object
1792f4a2713aSLionel Sambuc     //   types.
1793f4a2713aSLionel Sambuc     if (DestMemPtr->getPointeeType()->isFunctionType() !=
1794f4a2713aSLionel Sambuc         SrcMemPtr->getPointeeType()->isFunctionType())
1795f4a2713aSLionel Sambuc       return TC_NotApplicable;
1796f4a2713aSLionel Sambuc 
1797f4a2713aSLionel Sambuc     // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away
1798f4a2713aSLionel Sambuc     //   constness.
1799f4a2713aSLionel Sambuc     // A reinterpret_cast followed by a const_cast can, though, so in C-style,
1800f4a2713aSLionel Sambuc     // we accept it.
1801f4a2713aSLionel Sambuc     if (CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
1802f4a2713aSLionel Sambuc                            /*CheckObjCLifetime=*/CStyle)) {
1803f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_qualifiers_away;
1804f4a2713aSLionel Sambuc       return TC_Failed;
1805f4a2713aSLionel Sambuc     }
1806f4a2713aSLionel Sambuc 
1807*0a6a1f1dSLionel Sambuc     if (Self.Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1808*0a6a1f1dSLionel Sambuc       // We need to determine the inheritance model that the class will use if
1809*0a6a1f1dSLionel Sambuc       // haven't yet.
1810*0a6a1f1dSLionel Sambuc       Self.RequireCompleteType(OpRange.getBegin(), SrcType, 0);
1811*0a6a1f1dSLionel Sambuc       Self.RequireCompleteType(OpRange.getBegin(), DestType, 0);
1812*0a6a1f1dSLionel Sambuc     }
1813*0a6a1f1dSLionel Sambuc 
1814f4a2713aSLionel Sambuc     // Don't allow casting between member pointers of different sizes.
1815f4a2713aSLionel Sambuc     if (Self.Context.getTypeSize(DestMemPtr) !=
1816f4a2713aSLionel Sambuc         Self.Context.getTypeSize(SrcMemPtr)) {
1817f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_member_pointer_size;
1818f4a2713aSLionel Sambuc       return TC_Failed;
1819f4a2713aSLionel Sambuc     }
1820f4a2713aSLionel Sambuc 
1821f4a2713aSLionel Sambuc     // A valid member pointer cast.
1822f4a2713aSLionel Sambuc     assert(!IsLValueCast);
1823f4a2713aSLionel Sambuc     Kind = CK_ReinterpretMemberPointer;
1824f4a2713aSLionel Sambuc     return TC_Success;
1825f4a2713aSLionel Sambuc   }
1826f4a2713aSLionel Sambuc 
1827f4a2713aSLionel Sambuc   // See below for the enumeral issue.
1828f4a2713aSLionel Sambuc   if (SrcType->isNullPtrType() && DestType->isIntegralType(Self.Context)) {
1829f4a2713aSLionel Sambuc     // C++0x 5.2.10p4: A pointer can be explicitly converted to any integral
1830f4a2713aSLionel Sambuc     //   type large enough to hold it. A value of std::nullptr_t can be
1831f4a2713aSLionel Sambuc     //   converted to an integral type; the conversion has the same meaning
1832f4a2713aSLionel Sambuc     //   and validity as a conversion of (void*)0 to the integral type.
1833f4a2713aSLionel Sambuc     if (Self.Context.getTypeSize(SrcType) >
1834f4a2713aSLionel Sambuc         Self.Context.getTypeSize(DestType)) {
1835f4a2713aSLionel Sambuc       msg = diag::err_bad_reinterpret_cast_small_int;
1836f4a2713aSLionel Sambuc       return TC_Failed;
1837f4a2713aSLionel Sambuc     }
1838f4a2713aSLionel Sambuc     Kind = CK_PointerToIntegral;
1839f4a2713aSLionel Sambuc     return TC_Success;
1840f4a2713aSLionel Sambuc   }
1841f4a2713aSLionel Sambuc 
1842f4a2713aSLionel Sambuc   bool destIsVector = DestType->isVectorType();
1843f4a2713aSLionel Sambuc   bool srcIsVector = SrcType->isVectorType();
1844f4a2713aSLionel Sambuc   if (srcIsVector || destIsVector) {
1845f4a2713aSLionel Sambuc     // FIXME: Should this also apply to floating point types?
1846f4a2713aSLionel Sambuc     bool srcIsScalar = SrcType->isIntegralType(Self.Context);
1847f4a2713aSLionel Sambuc     bool destIsScalar = DestType->isIntegralType(Self.Context);
1848f4a2713aSLionel Sambuc 
1849f4a2713aSLionel Sambuc     // Check if this is a cast between a vector and something else.
1850f4a2713aSLionel Sambuc     if (!(srcIsScalar && destIsVector) && !(srcIsVector && destIsScalar) &&
1851f4a2713aSLionel Sambuc         !(srcIsVector && destIsVector))
1852f4a2713aSLionel Sambuc       return TC_NotApplicable;
1853f4a2713aSLionel Sambuc 
1854f4a2713aSLionel Sambuc     // If both types have the same size, we can successfully cast.
1855f4a2713aSLionel Sambuc     if (Self.Context.getTypeSize(SrcType)
1856f4a2713aSLionel Sambuc           == Self.Context.getTypeSize(DestType)) {
1857f4a2713aSLionel Sambuc       Kind = CK_BitCast;
1858f4a2713aSLionel Sambuc       return TC_Success;
1859f4a2713aSLionel Sambuc     }
1860f4a2713aSLionel Sambuc 
1861f4a2713aSLionel Sambuc     if (destIsScalar)
1862f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_vector_to_scalar_different_size;
1863f4a2713aSLionel Sambuc     else if (srcIsScalar)
1864f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_scalar_to_vector_different_size;
1865f4a2713aSLionel Sambuc     else
1866f4a2713aSLionel Sambuc       msg = diag::err_bad_cxx_cast_vector_to_vector_different_size;
1867f4a2713aSLionel Sambuc 
1868f4a2713aSLionel Sambuc     return TC_Failed;
1869f4a2713aSLionel Sambuc   }
1870f4a2713aSLionel Sambuc 
1871f4a2713aSLionel Sambuc   if (SrcType == DestType) {
1872f4a2713aSLionel Sambuc     // C++ 5.2.10p2 has a note that mentions that, subject to all other
1873f4a2713aSLionel Sambuc     // restrictions, a cast to the same type is allowed so long as it does not
1874f4a2713aSLionel Sambuc     // cast away constness. In C++98, the intent was not entirely clear here,
1875f4a2713aSLionel Sambuc     // since all other paragraphs explicitly forbid casts to the same type.
1876f4a2713aSLionel Sambuc     // C++11 clarifies this case with p2.
1877f4a2713aSLionel Sambuc     //
1878f4a2713aSLionel Sambuc     // The only allowed types are: integral, enumeration, pointer, or
1879f4a2713aSLionel Sambuc     // pointer-to-member types.  We also won't restrict Obj-C pointers either.
1880f4a2713aSLionel Sambuc     Kind = CK_NoOp;
1881f4a2713aSLionel Sambuc     TryCastResult Result = TC_NotApplicable;
1882f4a2713aSLionel Sambuc     if (SrcType->isIntegralOrEnumerationType() ||
1883f4a2713aSLionel Sambuc         SrcType->isAnyPointerType() ||
1884f4a2713aSLionel Sambuc         SrcType->isMemberPointerType() ||
1885f4a2713aSLionel Sambuc         SrcType->isBlockPointerType()) {
1886f4a2713aSLionel Sambuc       Result = TC_Success;
1887f4a2713aSLionel Sambuc     }
1888f4a2713aSLionel Sambuc     return Result;
1889f4a2713aSLionel Sambuc   }
1890f4a2713aSLionel Sambuc 
1891f4a2713aSLionel Sambuc   bool destIsPtr = DestType->isAnyPointerType() ||
1892f4a2713aSLionel Sambuc                    DestType->isBlockPointerType();
1893f4a2713aSLionel Sambuc   bool srcIsPtr = SrcType->isAnyPointerType() ||
1894f4a2713aSLionel Sambuc                   SrcType->isBlockPointerType();
1895f4a2713aSLionel Sambuc   if (!destIsPtr && !srcIsPtr) {
1896f4a2713aSLionel Sambuc     // Except for std::nullptr_t->integer and lvalue->reference, which are
1897f4a2713aSLionel Sambuc     // handled above, at least one of the two arguments must be a pointer.
1898f4a2713aSLionel Sambuc     return TC_NotApplicable;
1899f4a2713aSLionel Sambuc   }
1900f4a2713aSLionel Sambuc 
1901f4a2713aSLionel Sambuc   if (DestType->isIntegralType(Self.Context)) {
1902f4a2713aSLionel Sambuc     assert(srcIsPtr && "One type must be a pointer");
1903f4a2713aSLionel Sambuc     // C++ 5.2.10p4: A pointer can be explicitly converted to any integral
1904f4a2713aSLionel Sambuc     //   type large enough to hold it; except in Microsoft mode, where the
1905f4a2713aSLionel Sambuc     //   integral type size doesn't matter (except we don't allow bool).
1906f4a2713aSLionel Sambuc     bool MicrosoftException = Self.getLangOpts().MicrosoftExt &&
1907f4a2713aSLionel Sambuc                               !DestType->isBooleanType();
1908f4a2713aSLionel Sambuc     if ((Self.Context.getTypeSize(SrcType) >
1909f4a2713aSLionel Sambuc          Self.Context.getTypeSize(DestType)) &&
1910f4a2713aSLionel Sambuc          !MicrosoftException) {
1911f4a2713aSLionel Sambuc       msg = diag::err_bad_reinterpret_cast_small_int;
1912f4a2713aSLionel Sambuc       return TC_Failed;
1913f4a2713aSLionel Sambuc     }
1914f4a2713aSLionel Sambuc     Kind = CK_PointerToIntegral;
1915f4a2713aSLionel Sambuc     return TC_Success;
1916f4a2713aSLionel Sambuc   }
1917f4a2713aSLionel Sambuc 
1918f4a2713aSLionel Sambuc   if (SrcType->isIntegralOrEnumerationType()) {
1919f4a2713aSLionel Sambuc     assert(destIsPtr && "One type must be a pointer");
1920f4a2713aSLionel Sambuc     checkIntToPointerCast(CStyle, OpRange.getBegin(), SrcExpr.get(), DestType,
1921f4a2713aSLionel Sambuc                           Self);
1922f4a2713aSLionel Sambuc     // C++ 5.2.10p5: A value of integral or enumeration type can be explicitly
1923f4a2713aSLionel Sambuc     //   converted to a pointer.
1924f4a2713aSLionel Sambuc     // C++ 5.2.10p9: [Note: ...a null pointer constant of integral type is not
1925f4a2713aSLionel Sambuc     //   necessarily converted to a null pointer value.]
1926f4a2713aSLionel Sambuc     Kind = CK_IntegralToPointer;
1927f4a2713aSLionel Sambuc     return TC_Success;
1928f4a2713aSLionel Sambuc   }
1929f4a2713aSLionel Sambuc 
1930f4a2713aSLionel Sambuc   if (!destIsPtr || !srcIsPtr) {
1931f4a2713aSLionel Sambuc     // With the valid non-pointer conversions out of the way, we can be even
1932f4a2713aSLionel Sambuc     // more stringent.
1933f4a2713aSLionel Sambuc     return TC_NotApplicable;
1934f4a2713aSLionel Sambuc   }
1935f4a2713aSLionel Sambuc 
1936f4a2713aSLionel Sambuc   // C++ 5.2.10p2: The reinterpret_cast operator shall not cast away constness.
1937f4a2713aSLionel Sambuc   // The C-style cast operator can.
1938f4a2713aSLionel Sambuc   if (CastsAwayConstness(Self, SrcType, DestType, /*CheckCVR=*/!CStyle,
1939f4a2713aSLionel Sambuc                          /*CheckObjCLifetime=*/CStyle)) {
1940f4a2713aSLionel Sambuc     msg = diag::err_bad_cxx_cast_qualifiers_away;
1941f4a2713aSLionel Sambuc     return TC_Failed;
1942f4a2713aSLionel Sambuc   }
1943f4a2713aSLionel Sambuc 
1944f4a2713aSLionel Sambuc   // Cannot convert between block pointers and Objective-C object pointers.
1945f4a2713aSLionel Sambuc   if ((SrcType->isBlockPointerType() && DestType->isObjCObjectPointerType()) ||
1946f4a2713aSLionel Sambuc       (DestType->isBlockPointerType() && SrcType->isObjCObjectPointerType()))
1947f4a2713aSLionel Sambuc     return TC_NotApplicable;
1948f4a2713aSLionel Sambuc 
1949f4a2713aSLionel Sambuc   if (IsLValueCast) {
1950f4a2713aSLionel Sambuc     Kind = CK_LValueBitCast;
1951f4a2713aSLionel Sambuc   } else if (DestType->isObjCObjectPointerType()) {
1952f4a2713aSLionel Sambuc     Kind = Self.PrepareCastToObjCObjectPointer(SrcExpr);
1953f4a2713aSLionel Sambuc   } else if (DestType->isBlockPointerType()) {
1954f4a2713aSLionel Sambuc     if (!SrcType->isBlockPointerType()) {
1955f4a2713aSLionel Sambuc       Kind = CK_AnyPointerToBlockPointerCast;
1956f4a2713aSLionel Sambuc     } else {
1957f4a2713aSLionel Sambuc       Kind = CK_BitCast;
1958f4a2713aSLionel Sambuc     }
1959f4a2713aSLionel Sambuc   } else {
1960f4a2713aSLionel Sambuc     Kind = CK_BitCast;
1961f4a2713aSLionel Sambuc   }
1962f4a2713aSLionel Sambuc 
1963f4a2713aSLionel Sambuc   // Any pointer can be cast to an Objective-C pointer type with a C-style
1964f4a2713aSLionel Sambuc   // cast.
1965f4a2713aSLionel Sambuc   if (CStyle && DestType->isObjCObjectPointerType()) {
1966f4a2713aSLionel Sambuc     return TC_Success;
1967f4a2713aSLionel Sambuc   }
1968f4a2713aSLionel Sambuc   if (CStyle)
1969f4a2713aSLionel Sambuc     DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
1970f4a2713aSLionel Sambuc 
1971f4a2713aSLionel Sambuc   // Not casting away constness, so the only remaining check is for compatible
1972f4a2713aSLionel Sambuc   // pointer categories.
1973f4a2713aSLionel Sambuc 
1974f4a2713aSLionel Sambuc   if (SrcType->isFunctionPointerType()) {
1975f4a2713aSLionel Sambuc     if (DestType->isFunctionPointerType()) {
1976f4a2713aSLionel Sambuc       // C++ 5.2.10p6: A pointer to a function can be explicitly converted to
1977f4a2713aSLionel Sambuc       // a pointer to a function of a different type.
1978f4a2713aSLionel Sambuc       return TC_Success;
1979f4a2713aSLionel Sambuc     }
1980f4a2713aSLionel Sambuc 
1981f4a2713aSLionel Sambuc     // C++0x 5.2.10p8: Converting a pointer to a function into a pointer to
1982f4a2713aSLionel Sambuc     //   an object type or vice versa is conditionally-supported.
1983f4a2713aSLionel Sambuc     // Compilers support it in C++03 too, though, because it's necessary for
1984f4a2713aSLionel Sambuc     // casting the return value of dlsym() and GetProcAddress().
1985f4a2713aSLionel Sambuc     // FIXME: Conditionally-supported behavior should be configurable in the
1986f4a2713aSLionel Sambuc     // TargetInfo or similar.
1987f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(),
1988f4a2713aSLionel Sambuc               Self.getLangOpts().CPlusPlus11 ?
1989f4a2713aSLionel Sambuc                 diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
1990f4a2713aSLionel Sambuc       << OpRange;
1991f4a2713aSLionel Sambuc     return TC_Success;
1992f4a2713aSLionel Sambuc   }
1993f4a2713aSLionel Sambuc 
1994f4a2713aSLionel Sambuc   if (DestType->isFunctionPointerType()) {
1995f4a2713aSLionel Sambuc     // See above.
1996f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(),
1997f4a2713aSLionel Sambuc               Self.getLangOpts().CPlusPlus11 ?
1998f4a2713aSLionel Sambuc                 diag::warn_cxx98_compat_cast_fn_obj : diag::ext_cast_fn_obj)
1999f4a2713aSLionel Sambuc       << OpRange;
2000f4a2713aSLionel Sambuc     return TC_Success;
2001f4a2713aSLionel Sambuc   }
2002f4a2713aSLionel Sambuc 
2003f4a2713aSLionel Sambuc   // C++ 5.2.10p7: A pointer to an object can be explicitly converted to
2004f4a2713aSLionel Sambuc   //   a pointer to an object of different type.
2005f4a2713aSLionel Sambuc   // Void pointers are not specified, but supported by every compiler out there.
2006f4a2713aSLionel Sambuc   // So we finish by allowing everything that remains - it's got to be two
2007f4a2713aSLionel Sambuc   // object pointers.
2008f4a2713aSLionel Sambuc   return TC_Success;
2009f4a2713aSLionel Sambuc }
2010f4a2713aSLionel Sambuc 
CheckCXXCStyleCast(bool FunctionalStyle,bool ListInitialization)2011f4a2713aSLionel Sambuc void CastOperation::CheckCXXCStyleCast(bool FunctionalStyle,
2012f4a2713aSLionel Sambuc                                        bool ListInitialization) {
2013f4a2713aSLionel Sambuc   // Handle placeholders.
2014f4a2713aSLionel Sambuc   if (isPlaceholder()) {
2015f4a2713aSLionel Sambuc     // C-style casts can resolve __unknown_any types.
2016f4a2713aSLionel Sambuc     if (claimPlaceholder(BuiltinType::UnknownAny)) {
2017f4a2713aSLionel Sambuc       SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2018f4a2713aSLionel Sambuc                                          SrcExpr.get(), Kind,
2019f4a2713aSLionel Sambuc                                          ValueKind, BasePath);
2020f4a2713aSLionel Sambuc       return;
2021f4a2713aSLionel Sambuc     }
2022f4a2713aSLionel Sambuc 
2023f4a2713aSLionel Sambuc     checkNonOverloadPlaceholders();
2024f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
2025f4a2713aSLionel Sambuc       return;
2026f4a2713aSLionel Sambuc   }
2027f4a2713aSLionel Sambuc 
2028f4a2713aSLionel Sambuc   // C++ 5.2.9p4: Any expression can be explicitly converted to type "cv void".
2029f4a2713aSLionel Sambuc   // This test is outside everything else because it's the only case where
2030f4a2713aSLionel Sambuc   // a non-lvalue-reference target type does not lead to decay.
2031f4a2713aSLionel Sambuc   if (DestType->isVoidType()) {
2032f4a2713aSLionel Sambuc     Kind = CK_ToVoid;
2033f4a2713aSLionel Sambuc 
2034f4a2713aSLionel Sambuc     if (claimPlaceholder(BuiltinType::Overload)) {
2035f4a2713aSLionel Sambuc       Self.ResolveAndFixSingleFunctionTemplateSpecialization(
2036f4a2713aSLionel Sambuc                   SrcExpr, /* Decay Function to ptr */ false,
2037f4a2713aSLionel Sambuc                   /* Complain */ true, DestRange, DestType,
2038f4a2713aSLionel Sambuc                   diag::err_bad_cstyle_cast_overload);
2039f4a2713aSLionel Sambuc       if (SrcExpr.isInvalid())
2040f4a2713aSLionel Sambuc         return;
2041f4a2713aSLionel Sambuc     }
2042f4a2713aSLionel Sambuc 
2043*0a6a1f1dSLionel Sambuc     SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2044f4a2713aSLionel Sambuc     return;
2045f4a2713aSLionel Sambuc   }
2046f4a2713aSLionel Sambuc 
2047f4a2713aSLionel Sambuc   // If the type is dependent, we won't do any other semantic analysis now.
2048f4a2713aSLionel Sambuc   if (DestType->isDependentType() || SrcExpr.get()->isTypeDependent() ||
2049f4a2713aSLionel Sambuc       SrcExpr.get()->isValueDependent()) {
2050f4a2713aSLionel Sambuc     assert(Kind == CK_Dependent);
2051f4a2713aSLionel Sambuc     return;
2052f4a2713aSLionel Sambuc   }
2053f4a2713aSLionel Sambuc 
2054f4a2713aSLionel Sambuc   if (ValueKind == VK_RValue && !DestType->isRecordType() &&
2055f4a2713aSLionel Sambuc       !isPlaceholder(BuiltinType::Overload)) {
2056*0a6a1f1dSLionel Sambuc     SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2057f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
2058f4a2713aSLionel Sambuc       return;
2059f4a2713aSLionel Sambuc   }
2060f4a2713aSLionel Sambuc 
2061f4a2713aSLionel Sambuc   // AltiVec vector initialization with a single literal.
2062f4a2713aSLionel Sambuc   if (const VectorType *vecTy = DestType->getAs<VectorType>())
2063f4a2713aSLionel Sambuc     if (vecTy->getVectorKind() == VectorType::AltiVecVector
2064f4a2713aSLionel Sambuc         && (SrcExpr.get()->getType()->isIntegerType()
2065f4a2713aSLionel Sambuc             || SrcExpr.get()->getType()->isFloatingType())) {
2066f4a2713aSLionel Sambuc       Kind = CK_VectorSplat;
2067f4a2713aSLionel Sambuc       return;
2068f4a2713aSLionel Sambuc     }
2069f4a2713aSLionel Sambuc 
2070f4a2713aSLionel Sambuc   // C++ [expr.cast]p5: The conversions performed by
2071f4a2713aSLionel Sambuc   //   - a const_cast,
2072f4a2713aSLionel Sambuc   //   - a static_cast,
2073f4a2713aSLionel Sambuc   //   - a static_cast followed by a const_cast,
2074f4a2713aSLionel Sambuc   //   - a reinterpret_cast, or
2075f4a2713aSLionel Sambuc   //   - a reinterpret_cast followed by a const_cast,
2076f4a2713aSLionel Sambuc   //   can be performed using the cast notation of explicit type conversion.
2077f4a2713aSLionel Sambuc   //   [...] If a conversion can be interpreted in more than one of the ways
2078f4a2713aSLionel Sambuc   //   listed above, the interpretation that appears first in the list is used,
2079f4a2713aSLionel Sambuc   //   even if a cast resulting from that interpretation is ill-formed.
2080f4a2713aSLionel Sambuc   // In plain language, this means trying a const_cast ...
2081f4a2713aSLionel Sambuc   unsigned msg = diag::err_bad_cxx_cast_generic;
2082f4a2713aSLionel Sambuc   TryCastResult tcr = TryConstCast(Self, SrcExpr, DestType,
2083f4a2713aSLionel Sambuc                                    /*CStyle*/true, msg);
2084f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid())
2085f4a2713aSLionel Sambuc     return;
2086f4a2713aSLionel Sambuc   if (tcr == TC_Success)
2087f4a2713aSLionel Sambuc     Kind = CK_NoOp;
2088f4a2713aSLionel Sambuc 
2089f4a2713aSLionel Sambuc   Sema::CheckedConversionKind CCK
2090f4a2713aSLionel Sambuc     = FunctionalStyle? Sema::CCK_FunctionalCast
2091f4a2713aSLionel Sambuc                      : Sema::CCK_CStyleCast;
2092f4a2713aSLionel Sambuc   if (tcr == TC_NotApplicable) {
2093f4a2713aSLionel Sambuc     // ... or if that is not possible, a static_cast, ignoring const, ...
2094f4a2713aSLionel Sambuc     tcr = TryStaticCast(Self, SrcExpr, DestType, CCK, OpRange,
2095f4a2713aSLionel Sambuc                         msg, Kind, BasePath, ListInitialization);
2096f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
2097f4a2713aSLionel Sambuc       return;
2098f4a2713aSLionel Sambuc 
2099f4a2713aSLionel Sambuc     if (tcr == TC_NotApplicable) {
2100f4a2713aSLionel Sambuc       // ... and finally a reinterpret_cast, ignoring const.
2101f4a2713aSLionel Sambuc       tcr = TryReinterpretCast(Self, SrcExpr, DestType, /*CStyle*/true,
2102f4a2713aSLionel Sambuc                                OpRange, msg, Kind);
2103f4a2713aSLionel Sambuc       if (SrcExpr.isInvalid())
2104f4a2713aSLionel Sambuc         return;
2105f4a2713aSLionel Sambuc     }
2106f4a2713aSLionel Sambuc   }
2107f4a2713aSLionel Sambuc 
2108f4a2713aSLionel Sambuc   if (Self.getLangOpts().ObjCAutoRefCount && tcr == TC_Success)
2109f4a2713aSLionel Sambuc     checkObjCARCConversion(CCK);
2110f4a2713aSLionel Sambuc 
2111f4a2713aSLionel Sambuc   if (tcr != TC_Success && msg != 0) {
2112f4a2713aSLionel Sambuc     if (SrcExpr.get()->getType() == Self.Context.OverloadTy) {
2113f4a2713aSLionel Sambuc       DeclAccessPair Found;
2114f4a2713aSLionel Sambuc       FunctionDecl *Fn = Self.ResolveAddressOfOverloadedFunction(SrcExpr.get(),
2115f4a2713aSLionel Sambuc                                 DestType,
2116f4a2713aSLionel Sambuc                                 /*Complain*/ true,
2117f4a2713aSLionel Sambuc                                 Found);
2118*0a6a1f1dSLionel Sambuc       if (Fn) {
2119*0a6a1f1dSLionel Sambuc         // If DestType is a function type (not to be confused with the function
2120*0a6a1f1dSLionel Sambuc         // pointer type), it will be possible to resolve the function address,
2121*0a6a1f1dSLionel Sambuc         // but the type cast should be considered as failure.
2122*0a6a1f1dSLionel Sambuc         OverloadExpr *OE = OverloadExpr::find(SrcExpr.get()).Expression;
2123*0a6a1f1dSLionel Sambuc         Self.Diag(OpRange.getBegin(), diag::err_bad_cstyle_cast_overload)
2124*0a6a1f1dSLionel Sambuc           << OE->getName() << DestType << OpRange
2125*0a6a1f1dSLionel Sambuc           << OE->getQualifierLoc().getSourceRange();
2126*0a6a1f1dSLionel Sambuc         Self.NoteAllOverloadCandidates(SrcExpr.get());
2127*0a6a1f1dSLionel Sambuc       }
2128f4a2713aSLionel Sambuc     } else {
2129f4a2713aSLionel Sambuc       diagnoseBadCast(Self, msg, (FunctionalStyle ? CT_Functional : CT_CStyle),
2130f4a2713aSLionel Sambuc                       OpRange, SrcExpr.get(), DestType, ListInitialization);
2131f4a2713aSLionel Sambuc     }
2132f4a2713aSLionel Sambuc   } else if (Kind == CK_BitCast) {
2133f4a2713aSLionel Sambuc     checkCastAlign();
2134f4a2713aSLionel Sambuc   }
2135f4a2713aSLionel Sambuc 
2136f4a2713aSLionel Sambuc   // Clear out SrcExpr if there was a fatal error.
2137f4a2713aSLionel Sambuc   if (tcr != TC_Success)
2138f4a2713aSLionel Sambuc     SrcExpr = ExprError();
2139f4a2713aSLionel Sambuc }
2140f4a2713aSLionel Sambuc 
2141f4a2713aSLionel Sambuc /// DiagnoseBadFunctionCast - Warn whenever a function call is cast to a
2142f4a2713aSLionel Sambuc ///  non-matching type. Such as enum function call to int, int call to
2143f4a2713aSLionel Sambuc /// pointer; etc. Cast to 'void' is an exception.
DiagnoseBadFunctionCast(Sema & Self,const ExprResult & SrcExpr,QualType DestType)2144f4a2713aSLionel Sambuc static void DiagnoseBadFunctionCast(Sema &Self, const ExprResult &SrcExpr,
2145f4a2713aSLionel Sambuc                                   QualType DestType) {
2146*0a6a1f1dSLionel Sambuc   if (Self.Diags.isIgnored(diag::warn_bad_function_cast,
2147*0a6a1f1dSLionel Sambuc                            SrcExpr.get()->getExprLoc()))
2148f4a2713aSLionel Sambuc     return;
2149f4a2713aSLionel Sambuc 
2150f4a2713aSLionel Sambuc   if (!isa<CallExpr>(SrcExpr.get()))
2151f4a2713aSLionel Sambuc     return;
2152f4a2713aSLionel Sambuc 
2153f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr.get()->getType();
2154f4a2713aSLionel Sambuc   if (DestType.getUnqualifiedType()->isVoidType())
2155f4a2713aSLionel Sambuc     return;
2156f4a2713aSLionel Sambuc   if ((SrcType->isAnyPointerType() || SrcType->isBlockPointerType())
2157f4a2713aSLionel Sambuc       && (DestType->isAnyPointerType() || DestType->isBlockPointerType()))
2158f4a2713aSLionel Sambuc     return;
2159f4a2713aSLionel Sambuc   if (SrcType->isIntegerType() && DestType->isIntegerType() &&
2160f4a2713aSLionel Sambuc       (SrcType->isBooleanType() == DestType->isBooleanType()) &&
2161f4a2713aSLionel Sambuc       (SrcType->isEnumeralType() == DestType->isEnumeralType()))
2162f4a2713aSLionel Sambuc     return;
2163f4a2713aSLionel Sambuc   if (SrcType->isRealFloatingType() && DestType->isRealFloatingType())
2164f4a2713aSLionel Sambuc     return;
2165f4a2713aSLionel Sambuc   if (SrcType->isEnumeralType() && DestType->isEnumeralType())
2166f4a2713aSLionel Sambuc     return;
2167f4a2713aSLionel Sambuc   if (SrcType->isComplexType() && DestType->isComplexType())
2168f4a2713aSLionel Sambuc     return;
2169f4a2713aSLionel Sambuc   if (SrcType->isComplexIntegerType() && DestType->isComplexIntegerType())
2170f4a2713aSLionel Sambuc     return;
2171f4a2713aSLionel Sambuc 
2172f4a2713aSLionel Sambuc   Self.Diag(SrcExpr.get()->getExprLoc(),
2173f4a2713aSLionel Sambuc             diag::warn_bad_function_cast)
2174f4a2713aSLionel Sambuc             << SrcType << DestType << SrcExpr.get()->getSourceRange();
2175f4a2713aSLionel Sambuc }
2176f4a2713aSLionel Sambuc 
2177f4a2713aSLionel Sambuc /// Check the semantics of a C-style cast operation, in C.
CheckCStyleCast()2178f4a2713aSLionel Sambuc void CastOperation::CheckCStyleCast() {
2179f4a2713aSLionel Sambuc   assert(!Self.getLangOpts().CPlusPlus);
2180f4a2713aSLionel Sambuc 
2181f4a2713aSLionel Sambuc   // C-style casts can resolve __unknown_any types.
2182f4a2713aSLionel Sambuc   if (claimPlaceholder(BuiltinType::UnknownAny)) {
2183f4a2713aSLionel Sambuc     SrcExpr = Self.checkUnknownAnyCast(DestRange, DestType,
2184f4a2713aSLionel Sambuc                                        SrcExpr.get(), Kind,
2185f4a2713aSLionel Sambuc                                        ValueKind, BasePath);
2186f4a2713aSLionel Sambuc     return;
2187f4a2713aSLionel Sambuc   }
2188f4a2713aSLionel Sambuc 
2189f4a2713aSLionel Sambuc   // C99 6.5.4p2: the cast type needs to be void or scalar and the expression
2190f4a2713aSLionel Sambuc   // type needs to be scalar.
2191f4a2713aSLionel Sambuc   if (DestType->isVoidType()) {
2192f4a2713aSLionel Sambuc     // We don't necessarily do lvalue-to-rvalue conversions on this.
2193*0a6a1f1dSLionel Sambuc     SrcExpr = Self.IgnoredValueConversions(SrcExpr.get());
2194f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
2195f4a2713aSLionel Sambuc       return;
2196f4a2713aSLionel Sambuc 
2197f4a2713aSLionel Sambuc     // Cast to void allows any expr type.
2198f4a2713aSLionel Sambuc     Kind = CK_ToVoid;
2199f4a2713aSLionel Sambuc     return;
2200f4a2713aSLionel Sambuc   }
2201f4a2713aSLionel Sambuc 
2202*0a6a1f1dSLionel Sambuc   SrcExpr = Self.DefaultFunctionArrayLvalueConversion(SrcExpr.get());
2203f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid())
2204f4a2713aSLionel Sambuc     return;
2205f4a2713aSLionel Sambuc   QualType SrcType = SrcExpr.get()->getType();
2206f4a2713aSLionel Sambuc 
2207f4a2713aSLionel Sambuc   assert(!SrcType->isPlaceholderType());
2208f4a2713aSLionel Sambuc 
2209*0a6a1f1dSLionel Sambuc   // OpenCL v1 s6.5: Casting a pointer to address space A to a pointer to
2210*0a6a1f1dSLionel Sambuc   // address space B is illegal.
2211*0a6a1f1dSLionel Sambuc   if (Self.getLangOpts().OpenCL && DestType->isPointerType() &&
2212*0a6a1f1dSLionel Sambuc       SrcType->isPointerType()) {
2213*0a6a1f1dSLionel Sambuc     const PointerType *DestPtr = DestType->getAs<PointerType>();
2214*0a6a1f1dSLionel Sambuc     if (!DestPtr->isAddressSpaceOverlapping(*SrcType->getAs<PointerType>())) {
2215*0a6a1f1dSLionel Sambuc       Self.Diag(OpRange.getBegin(),
2216*0a6a1f1dSLionel Sambuc                 diag::err_typecheck_incompatible_address_space)
2217*0a6a1f1dSLionel Sambuc           << SrcType << DestType << Sema::AA_Casting
2218*0a6a1f1dSLionel Sambuc           << SrcExpr.get()->getSourceRange();
2219*0a6a1f1dSLionel Sambuc       SrcExpr = ExprError();
2220*0a6a1f1dSLionel Sambuc       return;
2221*0a6a1f1dSLionel Sambuc     }
2222*0a6a1f1dSLionel Sambuc   }
2223*0a6a1f1dSLionel Sambuc 
2224f4a2713aSLionel Sambuc   if (Self.RequireCompleteType(OpRange.getBegin(), DestType,
2225f4a2713aSLionel Sambuc                                diag::err_typecheck_cast_to_incomplete)) {
2226f4a2713aSLionel Sambuc     SrcExpr = ExprError();
2227f4a2713aSLionel Sambuc     return;
2228f4a2713aSLionel Sambuc   }
2229f4a2713aSLionel Sambuc 
2230f4a2713aSLionel Sambuc   if (!DestType->isScalarType() && !DestType->isVectorType()) {
2231f4a2713aSLionel Sambuc     const RecordType *DestRecordTy = DestType->getAs<RecordType>();
2232f4a2713aSLionel Sambuc 
2233f4a2713aSLionel Sambuc     if (DestRecordTy && Self.Context.hasSameUnqualifiedType(DestType, SrcType)){
2234f4a2713aSLionel Sambuc       // GCC struct/union extension: allow cast to self.
2235f4a2713aSLionel Sambuc       Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_nonscalar)
2236f4a2713aSLionel Sambuc         << DestType << SrcExpr.get()->getSourceRange();
2237f4a2713aSLionel Sambuc       Kind = CK_NoOp;
2238f4a2713aSLionel Sambuc       return;
2239f4a2713aSLionel Sambuc     }
2240f4a2713aSLionel Sambuc 
2241f4a2713aSLionel Sambuc     // GCC's cast to union extension.
2242f4a2713aSLionel Sambuc     if (DestRecordTy && DestRecordTy->getDecl()->isUnion()) {
2243f4a2713aSLionel Sambuc       RecordDecl *RD = DestRecordTy->getDecl();
2244f4a2713aSLionel Sambuc       RecordDecl::field_iterator Field, FieldEnd;
2245f4a2713aSLionel Sambuc       for (Field = RD->field_begin(), FieldEnd = RD->field_end();
2246f4a2713aSLionel Sambuc            Field != FieldEnd; ++Field) {
2247f4a2713aSLionel Sambuc         if (Self.Context.hasSameUnqualifiedType(Field->getType(), SrcType) &&
2248f4a2713aSLionel Sambuc             !Field->isUnnamedBitfield()) {
2249f4a2713aSLionel Sambuc           Self.Diag(OpRange.getBegin(), diag::ext_typecheck_cast_to_union)
2250f4a2713aSLionel Sambuc             << SrcExpr.get()->getSourceRange();
2251f4a2713aSLionel Sambuc           break;
2252f4a2713aSLionel Sambuc         }
2253f4a2713aSLionel Sambuc       }
2254f4a2713aSLionel Sambuc       if (Field == FieldEnd) {
2255f4a2713aSLionel Sambuc         Self.Diag(OpRange.getBegin(), diag::err_typecheck_cast_to_union_no_type)
2256f4a2713aSLionel Sambuc           << SrcType << SrcExpr.get()->getSourceRange();
2257f4a2713aSLionel Sambuc         SrcExpr = ExprError();
2258f4a2713aSLionel Sambuc         return;
2259f4a2713aSLionel Sambuc       }
2260f4a2713aSLionel Sambuc       Kind = CK_ToUnion;
2261f4a2713aSLionel Sambuc       return;
2262f4a2713aSLionel Sambuc     }
2263f4a2713aSLionel Sambuc 
2264f4a2713aSLionel Sambuc     // Reject any other conversions to non-scalar types.
2265f4a2713aSLionel Sambuc     Self.Diag(OpRange.getBegin(), diag::err_typecheck_cond_expect_scalar)
2266f4a2713aSLionel Sambuc       << DestType << SrcExpr.get()->getSourceRange();
2267f4a2713aSLionel Sambuc     SrcExpr = ExprError();
2268f4a2713aSLionel Sambuc     return;
2269f4a2713aSLionel Sambuc   }
2270f4a2713aSLionel Sambuc 
2271f4a2713aSLionel Sambuc   // The type we're casting to is known to be a scalar or vector.
2272f4a2713aSLionel Sambuc 
2273f4a2713aSLionel Sambuc   // Require the operand to be a scalar or vector.
2274f4a2713aSLionel Sambuc   if (!SrcType->isScalarType() && !SrcType->isVectorType()) {
2275f4a2713aSLionel Sambuc     Self.Diag(SrcExpr.get()->getExprLoc(),
2276f4a2713aSLionel Sambuc               diag::err_typecheck_expect_scalar_operand)
2277f4a2713aSLionel Sambuc       << SrcType << SrcExpr.get()->getSourceRange();
2278f4a2713aSLionel Sambuc     SrcExpr = ExprError();
2279f4a2713aSLionel Sambuc     return;
2280f4a2713aSLionel Sambuc   }
2281f4a2713aSLionel Sambuc 
2282f4a2713aSLionel Sambuc   if (DestType->isExtVectorType()) {
2283*0a6a1f1dSLionel Sambuc     SrcExpr = Self.CheckExtVectorCast(OpRange, DestType, SrcExpr.get(), Kind);
2284f4a2713aSLionel Sambuc     return;
2285f4a2713aSLionel Sambuc   }
2286f4a2713aSLionel Sambuc 
2287f4a2713aSLionel Sambuc   if (const VectorType *DestVecTy = DestType->getAs<VectorType>()) {
2288f4a2713aSLionel Sambuc     if (DestVecTy->getVectorKind() == VectorType::AltiVecVector &&
2289f4a2713aSLionel Sambuc           (SrcType->isIntegerType() || SrcType->isFloatingType())) {
2290f4a2713aSLionel Sambuc       Kind = CK_VectorSplat;
2291f4a2713aSLionel Sambuc     } else if (Self.CheckVectorCast(OpRange, DestType, SrcType, Kind)) {
2292f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2293f4a2713aSLionel Sambuc     }
2294f4a2713aSLionel Sambuc     return;
2295f4a2713aSLionel Sambuc   }
2296f4a2713aSLionel Sambuc 
2297f4a2713aSLionel Sambuc   if (SrcType->isVectorType()) {
2298f4a2713aSLionel Sambuc     if (Self.CheckVectorCast(OpRange, SrcType, DestType, Kind))
2299f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2300f4a2713aSLionel Sambuc     return;
2301f4a2713aSLionel Sambuc   }
2302f4a2713aSLionel Sambuc 
2303f4a2713aSLionel Sambuc   // The source and target types are both scalars, i.e.
2304f4a2713aSLionel Sambuc   //   - arithmetic types (fundamental, enum, and complex)
2305f4a2713aSLionel Sambuc   //   - all kinds of pointers
2306f4a2713aSLionel Sambuc   // Note that member pointers were filtered out with C++, above.
2307f4a2713aSLionel Sambuc 
2308f4a2713aSLionel Sambuc   if (isa<ObjCSelectorExpr>(SrcExpr.get())) {
2309f4a2713aSLionel Sambuc     Self.Diag(SrcExpr.get()->getExprLoc(), diag::err_cast_selector_expr);
2310f4a2713aSLionel Sambuc     SrcExpr = ExprError();
2311f4a2713aSLionel Sambuc     return;
2312f4a2713aSLionel Sambuc   }
2313f4a2713aSLionel Sambuc 
2314f4a2713aSLionel Sambuc   // If either type is a pointer, the other type has to be either an
2315f4a2713aSLionel Sambuc   // integer or a pointer.
2316f4a2713aSLionel Sambuc   if (!DestType->isArithmeticType()) {
2317f4a2713aSLionel Sambuc     if (!SrcType->isIntegralType(Self.Context) && SrcType->isArithmeticType()) {
2318f4a2713aSLionel Sambuc       Self.Diag(SrcExpr.get()->getExprLoc(),
2319f4a2713aSLionel Sambuc                 diag::err_cast_pointer_from_non_pointer_int)
2320f4a2713aSLionel Sambuc         << SrcType << SrcExpr.get()->getSourceRange();
2321f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2322f4a2713aSLionel Sambuc       return;
2323f4a2713aSLionel Sambuc     }
2324f4a2713aSLionel Sambuc     checkIntToPointerCast(/* CStyle */ true, OpRange.getBegin(), SrcExpr.get(),
2325f4a2713aSLionel Sambuc                           DestType, Self);
2326f4a2713aSLionel Sambuc   } else if (!SrcType->isArithmeticType()) {
2327f4a2713aSLionel Sambuc     if (!DestType->isIntegralType(Self.Context) &&
2328f4a2713aSLionel Sambuc         DestType->isArithmeticType()) {
2329f4a2713aSLionel Sambuc       Self.Diag(SrcExpr.get()->getLocStart(),
2330f4a2713aSLionel Sambuc            diag::err_cast_pointer_to_non_pointer_int)
2331f4a2713aSLionel Sambuc         << DestType << SrcExpr.get()->getSourceRange();
2332f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2333f4a2713aSLionel Sambuc       return;
2334f4a2713aSLionel Sambuc     }
2335f4a2713aSLionel Sambuc   }
2336f4a2713aSLionel Sambuc 
2337f4a2713aSLionel Sambuc   if (Self.getLangOpts().OpenCL && !Self.getOpenCLOptions().cl_khr_fp16) {
2338f4a2713aSLionel Sambuc     if (DestType->isHalfType()) {
2339f4a2713aSLionel Sambuc       Self.Diag(SrcExpr.get()->getLocStart(), diag::err_opencl_cast_to_half)
2340f4a2713aSLionel Sambuc         << DestType << SrcExpr.get()->getSourceRange();
2341f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2342f4a2713aSLionel Sambuc       return;
2343f4a2713aSLionel Sambuc     }
2344f4a2713aSLionel Sambuc   }
2345f4a2713aSLionel Sambuc 
2346f4a2713aSLionel Sambuc   // ARC imposes extra restrictions on casts.
2347f4a2713aSLionel Sambuc   if (Self.getLangOpts().ObjCAutoRefCount) {
2348f4a2713aSLionel Sambuc     checkObjCARCConversion(Sema::CCK_CStyleCast);
2349f4a2713aSLionel Sambuc     if (SrcExpr.isInvalid())
2350f4a2713aSLionel Sambuc       return;
2351f4a2713aSLionel Sambuc 
2352f4a2713aSLionel Sambuc     if (const PointerType *CastPtr = DestType->getAs<PointerType>()) {
2353f4a2713aSLionel Sambuc       if (const PointerType *ExprPtr = SrcType->getAs<PointerType>()) {
2354f4a2713aSLionel Sambuc         Qualifiers CastQuals = CastPtr->getPointeeType().getQualifiers();
2355f4a2713aSLionel Sambuc         Qualifiers ExprQuals = ExprPtr->getPointeeType().getQualifiers();
2356f4a2713aSLionel Sambuc         if (CastPtr->getPointeeType()->isObjCLifetimeType() &&
2357f4a2713aSLionel Sambuc             ExprPtr->getPointeeType()->isObjCLifetimeType() &&
2358f4a2713aSLionel Sambuc             !CastQuals.compatiblyIncludesObjCLifetime(ExprQuals)) {
2359f4a2713aSLionel Sambuc           Self.Diag(SrcExpr.get()->getLocStart(),
2360f4a2713aSLionel Sambuc                     diag::err_typecheck_incompatible_ownership)
2361f4a2713aSLionel Sambuc             << SrcType << DestType << Sema::AA_Casting
2362f4a2713aSLionel Sambuc             << SrcExpr.get()->getSourceRange();
2363f4a2713aSLionel Sambuc           return;
2364f4a2713aSLionel Sambuc         }
2365f4a2713aSLionel Sambuc       }
2366f4a2713aSLionel Sambuc     }
2367f4a2713aSLionel Sambuc     else if (!Self.CheckObjCARCUnavailableWeakConversion(DestType, SrcType)) {
2368f4a2713aSLionel Sambuc       Self.Diag(SrcExpr.get()->getLocStart(),
2369f4a2713aSLionel Sambuc                 diag::err_arc_convesion_of_weak_unavailable)
2370f4a2713aSLionel Sambuc         << 1 << SrcType << DestType << SrcExpr.get()->getSourceRange();
2371f4a2713aSLionel Sambuc       SrcExpr = ExprError();
2372f4a2713aSLionel Sambuc       return;
2373f4a2713aSLionel Sambuc     }
2374f4a2713aSLionel Sambuc   }
2375*0a6a1f1dSLionel Sambuc 
2376f4a2713aSLionel Sambuc   DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
2377f4a2713aSLionel Sambuc   DiagnoseBadFunctionCast(Self, SrcExpr, DestType);
2378f4a2713aSLionel Sambuc   Kind = Self.PrepareScalarCast(SrcExpr, DestType);
2379f4a2713aSLionel Sambuc   if (SrcExpr.isInvalid())
2380f4a2713aSLionel Sambuc     return;
2381f4a2713aSLionel Sambuc 
2382f4a2713aSLionel Sambuc   if (Kind == CK_BitCast)
2383f4a2713aSLionel Sambuc     checkCastAlign();
2384*0a6a1f1dSLionel Sambuc 
2385*0a6a1f1dSLionel Sambuc   // -Wcast-qual
2386*0a6a1f1dSLionel Sambuc   QualType TheOffendingSrcType, TheOffendingDestType;
2387*0a6a1f1dSLionel Sambuc   Qualifiers CastAwayQualifiers;
2388*0a6a1f1dSLionel Sambuc   if (SrcType->isAnyPointerType() && DestType->isAnyPointerType() &&
2389*0a6a1f1dSLionel Sambuc       CastsAwayConstness(Self, SrcType, DestType, true, false,
2390*0a6a1f1dSLionel Sambuc                          &TheOffendingSrcType, &TheOffendingDestType,
2391*0a6a1f1dSLionel Sambuc                          &CastAwayQualifiers)) {
2392*0a6a1f1dSLionel Sambuc     int qualifiers = -1;
2393*0a6a1f1dSLionel Sambuc     if (CastAwayQualifiers.hasConst() && CastAwayQualifiers.hasVolatile()) {
2394*0a6a1f1dSLionel Sambuc       qualifiers = 0;
2395*0a6a1f1dSLionel Sambuc     } else if (CastAwayQualifiers.hasConst()) {
2396*0a6a1f1dSLionel Sambuc       qualifiers = 1;
2397*0a6a1f1dSLionel Sambuc     } else if (CastAwayQualifiers.hasVolatile()) {
2398*0a6a1f1dSLionel Sambuc       qualifiers = 2;
2399*0a6a1f1dSLionel Sambuc     }
2400*0a6a1f1dSLionel Sambuc     // This is a variant of int **x; const int **y = (const int **)x;
2401*0a6a1f1dSLionel Sambuc     if (qualifiers == -1)
2402*0a6a1f1dSLionel Sambuc       Self.Diag(SrcExpr.get()->getLocStart(), diag::warn_cast_qual2) <<
2403*0a6a1f1dSLionel Sambuc         SrcType << DestType;
2404*0a6a1f1dSLionel Sambuc     else
2405*0a6a1f1dSLionel Sambuc       Self.Diag(SrcExpr.get()->getLocStart(), diag::warn_cast_qual) <<
2406*0a6a1f1dSLionel Sambuc         TheOffendingSrcType << TheOffendingDestType << qualifiers;
2407*0a6a1f1dSLionel Sambuc   }
2408f4a2713aSLionel Sambuc }
2409f4a2713aSLionel Sambuc 
BuildCStyleCastExpr(SourceLocation LPLoc,TypeSourceInfo * CastTypeInfo,SourceLocation RPLoc,Expr * CastExpr)2410f4a2713aSLionel Sambuc ExprResult Sema::BuildCStyleCastExpr(SourceLocation LPLoc,
2411f4a2713aSLionel Sambuc                                      TypeSourceInfo *CastTypeInfo,
2412f4a2713aSLionel Sambuc                                      SourceLocation RPLoc,
2413f4a2713aSLionel Sambuc                                      Expr *CastExpr) {
2414f4a2713aSLionel Sambuc   CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
2415f4a2713aSLionel Sambuc   Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2416f4a2713aSLionel Sambuc   Op.OpRange = SourceRange(LPLoc, CastExpr->getLocEnd());
2417f4a2713aSLionel Sambuc 
2418f4a2713aSLionel Sambuc   if (getLangOpts().CPlusPlus) {
2419f4a2713aSLionel Sambuc     Op.CheckCXXCStyleCast(/*FunctionalStyle=*/ false,
2420f4a2713aSLionel Sambuc                           isa<InitListExpr>(CastExpr));
2421f4a2713aSLionel Sambuc   } else {
2422f4a2713aSLionel Sambuc     Op.CheckCStyleCast();
2423f4a2713aSLionel Sambuc   }
2424f4a2713aSLionel Sambuc 
2425f4a2713aSLionel Sambuc   if (Op.SrcExpr.isInvalid())
2426f4a2713aSLionel Sambuc     return ExprError();
2427f4a2713aSLionel Sambuc 
2428f4a2713aSLionel Sambuc   return Op.complete(CStyleCastExpr::Create(Context, Op.ResultType,
2429*0a6a1f1dSLionel Sambuc                               Op.ValueKind, Op.Kind, Op.SrcExpr.get(),
2430f4a2713aSLionel Sambuc                               &Op.BasePath, CastTypeInfo, LPLoc, RPLoc));
2431f4a2713aSLionel Sambuc }
2432f4a2713aSLionel Sambuc 
BuildCXXFunctionalCastExpr(TypeSourceInfo * CastTypeInfo,SourceLocation LPLoc,Expr * CastExpr,SourceLocation RPLoc)2433f4a2713aSLionel Sambuc ExprResult Sema::BuildCXXFunctionalCastExpr(TypeSourceInfo *CastTypeInfo,
2434f4a2713aSLionel Sambuc                                             SourceLocation LPLoc,
2435f4a2713aSLionel Sambuc                                             Expr *CastExpr,
2436f4a2713aSLionel Sambuc                                             SourceLocation RPLoc) {
2437f4a2713aSLionel Sambuc   assert(LPLoc.isValid() && "List-initialization shouldn't get here.");
2438f4a2713aSLionel Sambuc   CastOperation Op(*this, CastTypeInfo->getType(), CastExpr);
2439f4a2713aSLionel Sambuc   Op.DestRange = CastTypeInfo->getTypeLoc().getSourceRange();
2440f4a2713aSLionel Sambuc   Op.OpRange = SourceRange(Op.DestRange.getBegin(), CastExpr->getLocEnd());
2441f4a2713aSLionel Sambuc 
2442f4a2713aSLionel Sambuc   Op.CheckCXXCStyleCast(/*FunctionalStyle=*/true, /*ListInit=*/false);
2443f4a2713aSLionel Sambuc   if (Op.SrcExpr.isInvalid())
2444f4a2713aSLionel Sambuc     return ExprError();
2445f4a2713aSLionel Sambuc 
2446f4a2713aSLionel Sambuc   if (CXXConstructExpr *ConstructExpr = dyn_cast<CXXConstructExpr>(Op.SrcExpr.get()))
2447f4a2713aSLionel Sambuc     ConstructExpr->setParenOrBraceRange(SourceRange(LPLoc, RPLoc));
2448f4a2713aSLionel Sambuc 
2449f4a2713aSLionel Sambuc   return Op.complete(CXXFunctionalCastExpr::Create(Context, Op.ResultType,
2450f4a2713aSLionel Sambuc                          Op.ValueKind, CastTypeInfo, Op.Kind,
2451*0a6a1f1dSLionel Sambuc                          Op.SrcExpr.get(), &Op.BasePath, LPLoc, RPLoc));
2452f4a2713aSLionel Sambuc }
2453