Bug Summary

File:tools/clang/lib/Sema/SemaOverload.cpp
Warning:line 9169, column 44
Called C++ object pointer is null

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaOverload.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-8~svn345461/tools/clang/include -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/tools/clang/lib/Sema -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp -faddrsig
1//===--- SemaOverload.cpp - C++ Overloading -------------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file provides Sema routines for C++ overloading.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Sema/Overload.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/CXXInheritance.h"
17#include "clang/AST/DeclObjC.h"
18#include "clang/AST/Expr.h"
19#include "clang/AST/ExprCXX.h"
20#include "clang/AST/ExprObjC.h"
21#include "clang/AST/TypeOrdering.h"
22#include "clang/Basic/Diagnostic.h"
23#include "clang/Basic/DiagnosticOptions.h"
24#include "clang/Basic/PartialDiagnostic.h"
25#include "clang/Basic/TargetInfo.h"
26#include "clang/Sema/Initialization.h"
27#include "clang/Sema/Lookup.h"
28#include "clang/Sema/SemaInternal.h"
29#include "clang/Sema/Template.h"
30#include "clang/Sema/TemplateDeduction.h"
31#include "llvm/ADT/DenseSet.h"
32#include "llvm/ADT/Optional.h"
33#include "llvm/ADT/STLExtras.h"
34#include "llvm/ADT/SmallPtrSet.h"
35#include "llvm/ADT/SmallString.h"
36#include <algorithm>
37#include <cstdlib>
38
39using namespace clang;
40using namespace sema;
41
42static bool functionHasPassObjectSizeParams(const FunctionDecl *FD) {
43 return llvm::any_of(FD->parameters(), [](const ParmVarDecl *P) {
44 return P->hasAttr<PassObjectSizeAttr>();
45 });
46}
47
48/// A convenience routine for creating a decayed reference to a function.
49static ExprResult
50CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, NamedDecl *FoundDecl,
51 const Expr *Base, bool HadMultipleCandidates,
52 SourceLocation Loc = SourceLocation(),
53 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){
54 if (S.DiagnoseUseOfDecl(FoundDecl, Loc))
55 return ExprError();
56 // If FoundDecl is different from Fn (such as if one is a template
57 // and the other a specialization), make sure DiagnoseUseOfDecl is
58 // called on both.
59 // FIXME: This would be more comprehensively addressed by modifying
60 // DiagnoseUseOfDecl to accept both the FoundDecl and the decl
61 // being used.
62 if (FoundDecl != Fn && S.DiagnoseUseOfDecl(Fn, Loc))
63 return ExprError();
64 if (auto *FPT = Fn->getType()->getAs<FunctionProtoType>())
65 S.ResolveExceptionSpec(Loc, FPT);
66 DeclRefExpr *DRE = new (S.Context) DeclRefExpr(Fn, false, Fn->getType(),
67 VK_LValue, Loc, LocInfo);
68 if (HadMultipleCandidates)
69 DRE->setHadMultipleCandidates(true);
70
71 S.MarkDeclRefReferenced(DRE, Base);
72 return S.ImpCastExprToType(DRE, S.Context.getPointerType(DRE->getType()),
73 CK_FunctionToPointerDecay);
74}
75
76static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
77 bool InOverloadResolution,
78 StandardConversionSequence &SCS,
79 bool CStyle,
80 bool AllowObjCWritebackConversion);
81
82static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From,
83 QualType &ToType,
84 bool InOverloadResolution,
85 StandardConversionSequence &SCS,
86 bool CStyle);
87static OverloadingResult
88IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
89 UserDefinedConversionSequence& User,
90 OverloadCandidateSet& Conversions,
91 bool AllowExplicit,
92 bool AllowObjCConversionOnExplicit);
93
94
95static ImplicitConversionSequence::CompareKind
96CompareStandardConversionSequences(Sema &S, SourceLocation Loc,
97 const StandardConversionSequence& SCS1,
98 const StandardConversionSequence& SCS2);
99
100static ImplicitConversionSequence::CompareKind
101CompareQualificationConversions(Sema &S,
102 const StandardConversionSequence& SCS1,
103 const StandardConversionSequence& SCS2);
104
105static ImplicitConversionSequence::CompareKind
106CompareDerivedToBaseConversions(Sema &S, SourceLocation Loc,
107 const StandardConversionSequence& SCS1,
108 const StandardConversionSequence& SCS2);
109
110/// GetConversionRank - Retrieve the implicit conversion rank
111/// corresponding to the given implicit conversion kind.
112ImplicitConversionRank clang::GetConversionRank(ImplicitConversionKind Kind) {
113 static const ImplicitConversionRank
114 Rank[(int)ICK_Num_Conversion_Kinds] = {
115 ICR_Exact_Match,
116 ICR_Exact_Match,
117 ICR_Exact_Match,
118 ICR_Exact_Match,
119 ICR_Exact_Match,
120 ICR_Exact_Match,
121 ICR_Promotion,
122 ICR_Promotion,
123 ICR_Promotion,
124 ICR_Conversion,
125 ICR_Conversion,
126 ICR_Conversion,
127 ICR_Conversion,
128 ICR_Conversion,
129 ICR_Conversion,
130 ICR_Conversion,
131 ICR_Conversion,
132 ICR_Conversion,
133 ICR_Conversion,
134 ICR_OCL_Scalar_Widening,
135 ICR_Complex_Real_Conversion,
136 ICR_Conversion,
137 ICR_Conversion,
138 ICR_Writeback_Conversion,
139 ICR_Exact_Match, // NOTE(gbiv): This may not be completely right --
140 // it was omitted by the patch that added
141 // ICK_Zero_Event_Conversion
142 ICR_C_Conversion,
143 ICR_C_Conversion_Extension
144 };
145 return Rank[(int)Kind];
146}
147
148/// GetImplicitConversionName - Return the name of this kind of
149/// implicit conversion.
150static const char* GetImplicitConversionName(ImplicitConversionKind Kind) {
151 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = {
152 "No conversion",
153 "Lvalue-to-rvalue",
154 "Array-to-pointer",
155 "Function-to-pointer",
156 "Function pointer conversion",
157 "Qualification",
158 "Integral promotion",
159 "Floating point promotion",
160 "Complex promotion",
161 "Integral conversion",
162 "Floating conversion",
163 "Complex conversion",
164 "Floating-integral conversion",
165 "Pointer conversion",
166 "Pointer-to-member conversion",
167 "Boolean conversion",
168 "Compatible-types conversion",
169 "Derived-to-base conversion",
170 "Vector conversion",
171 "Vector splat",
172 "Complex-real conversion",
173 "Block Pointer conversion",
174 "Transparent Union Conversion",
175 "Writeback conversion",
176 "OpenCL Zero Event Conversion",
177 "C specific type conversion",
178 "Incompatible pointer conversion"
179 };
180 return Name[Kind];
181}
182
183/// StandardConversionSequence - Set the standard conversion
184/// sequence to the identity conversion.
185void StandardConversionSequence::setAsIdentityConversion() {
186 First = ICK_Identity;
187 Second = ICK_Identity;
188 Third = ICK_Identity;
189 DeprecatedStringLiteralToCharPtr = false;
190 QualificationIncludesObjCLifetime = false;
191 ReferenceBinding = false;
192 DirectBinding = false;
193 IsLvalueReference = true;
194 BindsToFunctionLvalue = false;
195 BindsToRvalue = false;
196 BindsImplicitObjectArgumentWithoutRefQualifier = false;
197 ObjCLifetimeConversionBinding = false;
198 CopyConstructor = nullptr;
199}
200
201/// getRank - Retrieve the rank of this standard conversion sequence
202/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the
203/// implicit conversions.
204ImplicitConversionRank StandardConversionSequence::getRank() const {
205 ImplicitConversionRank Rank = ICR_Exact_Match;
206 if (GetConversionRank(First) > Rank)
207 Rank = GetConversionRank(First);
208 if (GetConversionRank(Second) > Rank)
209 Rank = GetConversionRank(Second);
210 if (GetConversionRank(Third) > Rank)
211 Rank = GetConversionRank(Third);
212 return Rank;
213}
214
215/// isPointerConversionToBool - Determines whether this conversion is
216/// a conversion of a pointer or pointer-to-member to bool. This is
217/// used as part of the ranking of standard conversion sequences
218/// (C++ 13.3.3.2p4).
219bool StandardConversionSequence::isPointerConversionToBool() const {
220 // Note that FromType has not necessarily been transformed by the
221 // array-to-pointer or function-to-pointer implicit conversions, so
222 // check for their presence as well as checking whether FromType is
223 // a pointer.
224 if (getToType(1)->isBooleanType() &&
225 (getFromType()->isPointerType() ||
226 getFromType()->isMemberPointerType() ||
227 getFromType()->isObjCObjectPointerType() ||
228 getFromType()->isBlockPointerType() ||
229 getFromType()->isNullPtrType() ||
230 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer))
231 return true;
232
233 return false;
234}
235
236/// isPointerConversionToVoidPointer - Determines whether this
237/// conversion is a conversion of a pointer to a void pointer. This is
238/// used as part of the ranking of standard conversion sequences (C++
239/// 13.3.3.2p4).
240bool
241StandardConversionSequence::
242isPointerConversionToVoidPointer(ASTContext& Context) const {
243 QualType FromType = getFromType();
244 QualType ToType = getToType(1);
245
246 // Note that FromType has not necessarily been transformed by the
247 // array-to-pointer implicit conversion, so check for its presence
248 // and redo the conversion to get a pointer.
249 if (First == ICK_Array_To_Pointer)
250 FromType = Context.getArrayDecayedType(FromType);
251
252 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType())
253 if (const PointerType* ToPtrType = ToType->getAs<PointerType>())
254 return ToPtrType->getPointeeType()->isVoidType();
255
256 return false;
257}
258
259/// Skip any implicit casts which could be either part of a narrowing conversion
260/// or after one in an implicit conversion.
261static const Expr *IgnoreNarrowingConversion(const Expr *Converted) {
262 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Converted)) {
263 switch (ICE->getCastKind()) {
264 case CK_NoOp:
265 case CK_IntegralCast:
266 case CK_IntegralToBoolean:
267 case CK_IntegralToFloating:
268 case CK_BooleanToSignedIntegral:
269 case CK_FloatingToIntegral:
270 case CK_FloatingToBoolean:
271 case CK_FloatingCast:
272 Converted = ICE->getSubExpr();
273 continue;
274
275 default:
276 return Converted;
277 }
278 }
279
280 return Converted;
281}
282
283/// Check if this standard conversion sequence represents a narrowing
284/// conversion, according to C++11 [dcl.init.list]p7.
285///
286/// \param Ctx The AST context.
287/// \param Converted The result of applying this standard conversion sequence.
288/// \param ConstantValue If this is an NK_Constant_Narrowing conversion, the
289/// value of the expression prior to the narrowing conversion.
290/// \param ConstantType If this is an NK_Constant_Narrowing conversion, the
291/// type of the expression prior to the narrowing conversion.
292/// \param IgnoreFloatToIntegralConversion If true type-narrowing conversions
293/// from floating point types to integral types should be ignored.
294NarrowingKind StandardConversionSequence::getNarrowingKind(
295 ASTContext &Ctx, const Expr *Converted, APValue &ConstantValue,
296 QualType &ConstantType, bool IgnoreFloatToIntegralConversion) const {
297 assert(Ctx.getLangOpts().CPlusPlus && "narrowing check outside C++")((Ctx.getLangOpts().CPlusPlus && "narrowing check outside C++"
) ? static_cast<void> (0) : __assert_fail ("Ctx.getLangOpts().CPlusPlus && \"narrowing check outside C++\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 297, __PRETTY_FUNCTION__))
;
298
299 // C++11 [dcl.init.list]p7:
300 // A narrowing conversion is an implicit conversion ...
301 QualType FromType = getToType(0);
302 QualType ToType = getToType(1);
303
304 // A conversion to an enumeration type is narrowing if the conversion to
305 // the underlying type is narrowing. This only arises for expressions of
306 // the form 'Enum{init}'.
307 if (auto *ET = ToType->getAs<EnumType>())
308 ToType = ET->getDecl()->getIntegerType();
309
310 switch (Second) {
311 // 'bool' is an integral type; dispatch to the right place to handle it.
312 case ICK_Boolean_Conversion:
313 if (FromType->isRealFloatingType())
314 goto FloatingIntegralConversion;
315 if (FromType->isIntegralOrUnscopedEnumerationType())
316 goto IntegralConversion;
317 // Boolean conversions can be from pointers and pointers to members
318 // [conv.bool], and those aren't considered narrowing conversions.
319 return NK_Not_Narrowing;
320
321 // -- from a floating-point type to an integer type, or
322 //
323 // -- from an integer type or unscoped enumeration type to a floating-point
324 // type, except where the source is a constant expression and the actual
325 // value after conversion will fit into the target type and will produce
326 // the original value when converted back to the original type, or
327 case ICK_Floating_Integral:
328 FloatingIntegralConversion:
329 if (FromType->isRealFloatingType() && ToType->isIntegralType(Ctx)) {
330 return NK_Type_Narrowing;
331 } else if (FromType->isIntegralOrUnscopedEnumerationType() &&
332 ToType->isRealFloatingType()) {
333 if (IgnoreFloatToIntegralConversion)
334 return NK_Not_Narrowing;
335 llvm::APSInt IntConstantValue;
336 const Expr *Initializer = IgnoreNarrowingConversion(Converted);
337 assert(Initializer && "Unknown conversion expression")((Initializer && "Unknown conversion expression") ? static_cast
<void> (0) : __assert_fail ("Initializer && \"Unknown conversion expression\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 337, __PRETTY_FUNCTION__))
;
338
339 // If it's value-dependent, we can't tell whether it's narrowing.
340 if (Initializer->isValueDependent())
341 return NK_Dependent_Narrowing;
342
343 if (Initializer->isIntegerConstantExpr(IntConstantValue, Ctx)) {
344 // Convert the integer to the floating type.
345 llvm::APFloat Result(Ctx.getFloatTypeSemantics(ToType));
346 Result.convertFromAPInt(IntConstantValue, IntConstantValue.isSigned(),
347 llvm::APFloat::rmNearestTiesToEven);
348 // And back.
349 llvm::APSInt ConvertedValue = IntConstantValue;
350 bool ignored;
351 Result.convertToInteger(ConvertedValue,
352 llvm::APFloat::rmTowardZero, &ignored);
353 // If the resulting value is different, this was a narrowing conversion.
354 if (IntConstantValue != ConvertedValue) {
355 ConstantValue = APValue(IntConstantValue);
356 ConstantType = Initializer->getType();
357 return NK_Constant_Narrowing;
358 }
359 } else {
360 // Variables are always narrowings.
361 return NK_Variable_Narrowing;
362 }
363 }
364 return NK_Not_Narrowing;
365
366 // -- from long double to double or float, or from double to float, except
367 // where the source is a constant expression and the actual value after
368 // conversion is within the range of values that can be represented (even
369 // if it cannot be represented exactly), or
370 case ICK_Floating_Conversion:
371 if (FromType->isRealFloatingType() && ToType->isRealFloatingType() &&
372 Ctx.getFloatingTypeOrder(FromType, ToType) == 1) {
373 // FromType is larger than ToType.
374 const Expr *Initializer = IgnoreNarrowingConversion(Converted);
375
376 // If it's value-dependent, we can't tell whether it's narrowing.
377 if (Initializer->isValueDependent())
378 return NK_Dependent_Narrowing;
379
380 if (Initializer->isCXX11ConstantExpr(Ctx, &ConstantValue)) {
381 // Constant!
382 assert(ConstantValue.isFloat())((ConstantValue.isFloat()) ? static_cast<void> (0) : __assert_fail
("ConstantValue.isFloat()", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 382, __PRETTY_FUNCTION__))
;
383 llvm::APFloat FloatVal = ConstantValue.getFloat();
384 // Convert the source value into the target type.
385 bool ignored;
386 llvm::APFloat::opStatus ConvertStatus = FloatVal.convert(
387 Ctx.getFloatTypeSemantics(ToType),
388 llvm::APFloat::rmNearestTiesToEven, &ignored);
389 // If there was no overflow, the source value is within the range of
390 // values that can be represented.
391 if (ConvertStatus & llvm::APFloat::opOverflow) {
392 ConstantType = Initializer->getType();
393 return NK_Constant_Narrowing;
394 }
395 } else {
396 return NK_Variable_Narrowing;
397 }
398 }
399 return NK_Not_Narrowing;
400
401 // -- from an integer type or unscoped enumeration type to an integer type
402 // that cannot represent all the values of the original type, except where
403 // the source is a constant expression and the actual value after
404 // conversion will fit into the target type and will produce the original
405 // value when converted back to the original type.
406 case ICK_Integral_Conversion:
407 IntegralConversion: {
408 assert(FromType->isIntegralOrUnscopedEnumerationType())((FromType->isIntegralOrUnscopedEnumerationType()) ? static_cast
<void> (0) : __assert_fail ("FromType->isIntegralOrUnscopedEnumerationType()"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 408, __PRETTY_FUNCTION__))
;
409 assert(ToType->isIntegralOrUnscopedEnumerationType())((ToType->isIntegralOrUnscopedEnumerationType()) ? static_cast
<void> (0) : __assert_fail ("ToType->isIntegralOrUnscopedEnumerationType()"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 409, __PRETTY_FUNCTION__))
;
410 const bool FromSigned = FromType->isSignedIntegerOrEnumerationType();
411 const unsigned FromWidth = Ctx.getIntWidth(FromType);
412 const bool ToSigned = ToType->isSignedIntegerOrEnumerationType();
413 const unsigned ToWidth = Ctx.getIntWidth(ToType);
414
415 if (FromWidth > ToWidth ||
416 (FromWidth == ToWidth && FromSigned != ToSigned) ||
417 (FromSigned && !ToSigned)) {
418 // Not all values of FromType can be represented in ToType.
419 llvm::APSInt InitializerValue;
420 const Expr *Initializer = IgnoreNarrowingConversion(Converted);
421
422 // If it's value-dependent, we can't tell whether it's narrowing.
423 if (Initializer->isValueDependent())
424 return NK_Dependent_Narrowing;
425
426 if (!Initializer->isIntegerConstantExpr(InitializerValue, Ctx)) {
427 // Such conversions on variables are always narrowing.
428 return NK_Variable_Narrowing;
429 }
430 bool Narrowing = false;
431 if (FromWidth < ToWidth) {
432 // Negative -> unsigned is narrowing. Otherwise, more bits is never
433 // narrowing.
434 if (InitializerValue.isSigned() && InitializerValue.isNegative())
435 Narrowing = true;
436 } else {
437 // Add a bit to the InitializerValue so we don't have to worry about
438 // signed vs. unsigned comparisons.
439 InitializerValue = InitializerValue.extend(
440 InitializerValue.getBitWidth() + 1);
441 // Convert the initializer to and from the target width and signed-ness.
442 llvm::APSInt ConvertedValue = InitializerValue;
443 ConvertedValue = ConvertedValue.trunc(ToWidth);
444 ConvertedValue.setIsSigned(ToSigned);
445 ConvertedValue = ConvertedValue.extend(InitializerValue.getBitWidth());
446 ConvertedValue.setIsSigned(InitializerValue.isSigned());
447 // If the result is different, this was a narrowing conversion.
448 if (ConvertedValue != InitializerValue)
449 Narrowing = true;
450 }
451 if (Narrowing) {
452 ConstantType = Initializer->getType();
453 ConstantValue = APValue(InitializerValue);
454 return NK_Constant_Narrowing;
455 }
456 }
457 return NK_Not_Narrowing;
458 }
459
460 default:
461 // Other kinds of conversions are not narrowings.
462 return NK_Not_Narrowing;
463 }
464}
465
466/// dump - Print this standard conversion sequence to standard
467/// error. Useful for debugging overloading issues.
468LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void StandardConversionSequence::dump() const {
469 raw_ostream &OS = llvm::errs();
470 bool PrintedSomething = false;
471 if (First != ICK_Identity) {
472 OS << GetImplicitConversionName(First);
473 PrintedSomething = true;
474 }
475
476 if (Second != ICK_Identity) {
477 if (PrintedSomething) {
478 OS << " -> ";
479 }
480 OS << GetImplicitConversionName(Second);
481
482 if (CopyConstructor) {
483 OS << " (by copy constructor)";
484 } else if (DirectBinding) {
485 OS << " (direct reference binding)";
486 } else if (ReferenceBinding) {
487 OS << " (reference binding)";
488 }
489 PrintedSomething = true;
490 }
491
492 if (Third != ICK_Identity) {
493 if (PrintedSomething) {
494 OS << " -> ";
495 }
496 OS << GetImplicitConversionName(Third);
497 PrintedSomething = true;
498 }
499
500 if (!PrintedSomething) {
501 OS << "No conversions required";
502 }
503}
504
505/// dump - Print this user-defined conversion sequence to standard
506/// error. Useful for debugging overloading issues.
507void UserDefinedConversionSequence::dump() const {
508 raw_ostream &OS = llvm::errs();
509 if (Before.First || Before.Second || Before.Third) {
510 Before.dump();
511 OS << " -> ";
512 }
513 if (ConversionFunction)
514 OS << '\'' << *ConversionFunction << '\'';
515 else
516 OS << "aggregate initialization";
517 if (After.First || After.Second || After.Third) {
518 OS << " -> ";
519 After.dump();
520 }
521}
522
523/// dump - Print this implicit conversion sequence to standard
524/// error. Useful for debugging overloading issues.
525void ImplicitConversionSequence::dump() const {
526 raw_ostream &OS = llvm::errs();
527 if (isStdInitializerListElement())
528 OS << "Worst std::initializer_list element conversion: ";
529 switch (ConversionKind) {
530 case StandardConversion:
531 OS << "Standard conversion: ";
532 Standard.dump();
533 break;
534 case UserDefinedConversion:
535 OS << "User-defined conversion: ";
536 UserDefined.dump();
537 break;
538 case EllipsisConversion:
539 OS << "Ellipsis conversion";
540 break;
541 case AmbiguousConversion:
542 OS << "Ambiguous conversion";
543 break;
544 case BadConversion:
545 OS << "Bad conversion";
546 break;
547 }
548
549 OS << "\n";
550}
551
552void AmbiguousConversionSequence::construct() {
553 new (&conversions()) ConversionSet();
554}
555
556void AmbiguousConversionSequence::destruct() {
557 conversions().~ConversionSet();
558}
559
560void
561AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) {
562 FromTypePtr = O.FromTypePtr;
563 ToTypePtr = O.ToTypePtr;
564 new (&conversions()) ConversionSet(O.conversions());
565}
566
567namespace {
568 // Structure used by DeductionFailureInfo to store
569 // template argument information.
570 struct DFIArguments {
571 TemplateArgument FirstArg;
572 TemplateArgument SecondArg;
573 };
574 // Structure used by DeductionFailureInfo to store
575 // template parameter and template argument information.
576 struct DFIParamWithArguments : DFIArguments {
577 TemplateParameter Param;
578 };
579 // Structure used by DeductionFailureInfo to store template argument
580 // information and the index of the problematic call argument.
581 struct DFIDeducedMismatchArgs : DFIArguments {
582 TemplateArgumentList *TemplateArgs;
583 unsigned CallArgIndex;
584 };
585}
586
587/// Convert from Sema's representation of template deduction information
588/// to the form used in overload-candidate information.
589DeductionFailureInfo
590clang::MakeDeductionFailureInfo(ASTContext &Context,
591 Sema::TemplateDeductionResult TDK,
592 TemplateDeductionInfo &Info) {
593 DeductionFailureInfo Result;
594 Result.Result = static_cast<unsigned>(TDK);
595 Result.HasDiagnostic = false;
596 switch (TDK) {
597 case Sema::TDK_Invalid:
598 case Sema::TDK_InstantiationDepth:
599 case Sema::TDK_TooManyArguments:
600 case Sema::TDK_TooFewArguments:
601 case Sema::TDK_MiscellaneousDeductionFailure:
602 case Sema::TDK_CUDATargetMismatch:
603 Result.Data = nullptr;
604 break;
605
606 case Sema::TDK_Incomplete:
607 case Sema::TDK_InvalidExplicitArguments:
608 Result.Data = Info.Param.getOpaqueValue();
609 break;
610
611 case Sema::TDK_DeducedMismatch:
612 case Sema::TDK_DeducedMismatchNested: {
613 // FIXME: Should allocate from normal heap so that we can free this later.
614 auto *Saved = new (Context) DFIDeducedMismatchArgs;
615 Saved->FirstArg = Info.FirstArg;
616 Saved->SecondArg = Info.SecondArg;
617 Saved->TemplateArgs = Info.take();
618 Saved->CallArgIndex = Info.CallArgIndex;
619 Result.Data = Saved;
620 break;
621 }
622
623 case Sema::TDK_NonDeducedMismatch: {
624 // FIXME: Should allocate from normal heap so that we can free this later.
625 DFIArguments *Saved = new (Context) DFIArguments;
626 Saved->FirstArg = Info.FirstArg;
627 Saved->SecondArg = Info.SecondArg;
628 Result.Data = Saved;
629 break;
630 }
631
632 case Sema::TDK_IncompletePack:
633 // FIXME: It's slightly wasteful to allocate two TemplateArguments for this.
634 case Sema::TDK_Inconsistent:
635 case Sema::TDK_Underqualified: {
636 // FIXME: Should allocate from normal heap so that we can free this later.
637 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments;
638 Saved->Param = Info.Param;
639 Saved->FirstArg = Info.FirstArg;
640 Saved->SecondArg = Info.SecondArg;
641 Result.Data = Saved;
642 break;
643 }
644
645 case Sema::TDK_SubstitutionFailure:
646 Result.Data = Info.take();
647 if (Info.hasSFINAEDiagnostic()) {
648 PartialDiagnosticAt *Diag = new (Result.Diagnostic) PartialDiagnosticAt(
649 SourceLocation(), PartialDiagnostic::NullDiagnostic());
650 Info.takeSFINAEDiagnostic(*Diag);
651 Result.HasDiagnostic = true;
652 }
653 break;
654
655 case Sema::TDK_Success:
656 case Sema::TDK_NonDependentConversionFailure:
657 llvm_unreachable("not a deduction failure")::llvm::llvm_unreachable_internal("not a deduction failure", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 657)
;
658 }
659
660 return Result;
661}
662
663void DeductionFailureInfo::Destroy() {
664 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
665 case Sema::TDK_Success:
666 case Sema::TDK_Invalid:
667 case Sema::TDK_InstantiationDepth:
668 case Sema::TDK_Incomplete:
669 case Sema::TDK_TooManyArguments:
670 case Sema::TDK_TooFewArguments:
671 case Sema::TDK_InvalidExplicitArguments:
672 case Sema::TDK_CUDATargetMismatch:
673 case Sema::TDK_NonDependentConversionFailure:
674 break;
675
676 case Sema::TDK_IncompletePack:
677 case Sema::TDK_Inconsistent:
678 case Sema::TDK_Underqualified:
679 case Sema::TDK_DeducedMismatch:
680 case Sema::TDK_DeducedMismatchNested:
681 case Sema::TDK_NonDeducedMismatch:
682 // FIXME: Destroy the data?
683 Data = nullptr;
684 break;
685
686 case Sema::TDK_SubstitutionFailure:
687 // FIXME: Destroy the template argument list?
688 Data = nullptr;
689 if (PartialDiagnosticAt *Diag = getSFINAEDiagnostic()) {
690 Diag->~PartialDiagnosticAt();
691 HasDiagnostic = false;
692 }
693 break;
694
695 // Unhandled
696 case Sema::TDK_MiscellaneousDeductionFailure:
697 break;
698 }
699}
700
701PartialDiagnosticAt *DeductionFailureInfo::getSFINAEDiagnostic() {
702 if (HasDiagnostic)
703 return static_cast<PartialDiagnosticAt*>(static_cast<void*>(Diagnostic));
704 return nullptr;
705}
706
707TemplateParameter DeductionFailureInfo::getTemplateParameter() {
708 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
709 case Sema::TDK_Success:
710 case Sema::TDK_Invalid:
711 case Sema::TDK_InstantiationDepth:
712 case Sema::TDK_TooManyArguments:
713 case Sema::TDK_TooFewArguments:
714 case Sema::TDK_SubstitutionFailure:
715 case Sema::TDK_DeducedMismatch:
716 case Sema::TDK_DeducedMismatchNested:
717 case Sema::TDK_NonDeducedMismatch:
718 case Sema::TDK_CUDATargetMismatch:
719 case Sema::TDK_NonDependentConversionFailure:
720 return TemplateParameter();
721
722 case Sema::TDK_Incomplete:
723 case Sema::TDK_InvalidExplicitArguments:
724 return TemplateParameter::getFromOpaqueValue(Data);
725
726 case Sema::TDK_IncompletePack:
727 case Sema::TDK_Inconsistent:
728 case Sema::TDK_Underqualified:
729 return static_cast<DFIParamWithArguments*>(Data)->Param;
730
731 // Unhandled
732 case Sema::TDK_MiscellaneousDeductionFailure:
733 break;
734 }
735
736 return TemplateParameter();
737}
738
739TemplateArgumentList *DeductionFailureInfo::getTemplateArgumentList() {
740 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
741 case Sema::TDK_Success:
742 case Sema::TDK_Invalid:
743 case Sema::TDK_InstantiationDepth:
744 case Sema::TDK_TooManyArguments:
745 case Sema::TDK_TooFewArguments:
746 case Sema::TDK_Incomplete:
747 case Sema::TDK_IncompletePack:
748 case Sema::TDK_InvalidExplicitArguments:
749 case Sema::TDK_Inconsistent:
750 case Sema::TDK_Underqualified:
751 case Sema::TDK_NonDeducedMismatch:
752 case Sema::TDK_CUDATargetMismatch:
753 case Sema::TDK_NonDependentConversionFailure:
754 return nullptr;
755
756 case Sema::TDK_DeducedMismatch:
757 case Sema::TDK_DeducedMismatchNested:
758 return static_cast<DFIDeducedMismatchArgs*>(Data)->TemplateArgs;
759
760 case Sema::TDK_SubstitutionFailure:
761 return static_cast<TemplateArgumentList*>(Data);
762
763 // Unhandled
764 case Sema::TDK_MiscellaneousDeductionFailure:
765 break;
766 }
767
768 return nullptr;
769}
770
771const TemplateArgument *DeductionFailureInfo::getFirstArg() {
772 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
773 case Sema::TDK_Success:
774 case Sema::TDK_Invalid:
775 case Sema::TDK_InstantiationDepth:
776 case Sema::TDK_Incomplete:
777 case Sema::TDK_TooManyArguments:
778 case Sema::TDK_TooFewArguments:
779 case Sema::TDK_InvalidExplicitArguments:
780 case Sema::TDK_SubstitutionFailure:
781 case Sema::TDK_CUDATargetMismatch:
782 case Sema::TDK_NonDependentConversionFailure:
783 return nullptr;
784
785 case Sema::TDK_IncompletePack:
786 case Sema::TDK_Inconsistent:
787 case Sema::TDK_Underqualified:
788 case Sema::TDK_DeducedMismatch:
789 case Sema::TDK_DeducedMismatchNested:
790 case Sema::TDK_NonDeducedMismatch:
791 return &static_cast<DFIArguments*>(Data)->FirstArg;
792
793 // Unhandled
794 case Sema::TDK_MiscellaneousDeductionFailure:
795 break;
796 }
797
798 return nullptr;
799}
800
801const TemplateArgument *DeductionFailureInfo::getSecondArg() {
802 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
803 case Sema::TDK_Success:
804 case Sema::TDK_Invalid:
805 case Sema::TDK_InstantiationDepth:
806 case Sema::TDK_Incomplete:
807 case Sema::TDK_IncompletePack:
808 case Sema::TDK_TooManyArguments:
809 case Sema::TDK_TooFewArguments:
810 case Sema::TDK_InvalidExplicitArguments:
811 case Sema::TDK_SubstitutionFailure:
812 case Sema::TDK_CUDATargetMismatch:
813 case Sema::TDK_NonDependentConversionFailure:
814 return nullptr;
815
816 case Sema::TDK_Inconsistent:
817 case Sema::TDK_Underqualified:
818 case Sema::TDK_DeducedMismatch:
819 case Sema::TDK_DeducedMismatchNested:
820 case Sema::TDK_NonDeducedMismatch:
821 return &static_cast<DFIArguments*>(Data)->SecondArg;
822
823 // Unhandled
824 case Sema::TDK_MiscellaneousDeductionFailure:
825 break;
826 }
827
828 return nullptr;
829}
830
831llvm::Optional<unsigned> DeductionFailureInfo::getCallArgIndex() {
832 switch (static_cast<Sema::TemplateDeductionResult>(Result)) {
833 case Sema::TDK_DeducedMismatch:
834 case Sema::TDK_DeducedMismatchNested:
835 return static_cast<DFIDeducedMismatchArgs*>(Data)->CallArgIndex;
836
837 default:
838 return llvm::None;
839 }
840}
841
842void OverloadCandidateSet::destroyCandidates() {
843 for (iterator i = begin(), e = end(); i != e; ++i) {
844 for (auto &C : i->Conversions)
845 C.~ImplicitConversionSequence();
846 if (!i->Viable && i->FailureKind == ovl_fail_bad_deduction)
847 i->DeductionFailure.Destroy();
848 }
849}
850
851void OverloadCandidateSet::clear(CandidateSetKind CSK) {
852 destroyCandidates();
853 SlabAllocator.Reset();
854 NumInlineBytesUsed = 0;
855 Candidates.clear();
856 Functions.clear();
857 Kind = CSK;
858}
859
860namespace {
861 class UnbridgedCastsSet {
862 struct Entry {
863 Expr **Addr;
864 Expr *Saved;
865 };
866 SmallVector<Entry, 2> Entries;
867
868 public:
869 void save(Sema &S, Expr *&E) {
870 assert(E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast))((E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast)) ? static_cast
<void> (0) : __assert_fail ("E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast)"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 870, __PRETTY_FUNCTION__))
;
871 Entry entry = { &E, E };
872 Entries.push_back(entry);
873 E = S.stripARCUnbridgedCast(E);
874 }
875
876 void restore() {
877 for (SmallVectorImpl<Entry>::iterator
878 i = Entries.begin(), e = Entries.end(); i != e; ++i)
879 *i->Addr = i->Saved;
880 }
881 };
882}
883
884/// checkPlaceholderForOverload - Do any interesting placeholder-like
885/// preprocessing on the given expression.
886///
887/// \param unbridgedCasts a collection to which to add unbridged casts;
888/// without this, they will be immediately diagnosed as errors
889///
890/// Return true on unrecoverable error.
891static bool
892checkPlaceholderForOverload(Sema &S, Expr *&E,
893 UnbridgedCastsSet *unbridgedCasts = nullptr) {
894 if (const BuiltinType *placeholder = E->getType()->getAsPlaceholderType()) {
895 // We can't handle overloaded expressions here because overload
896 // resolution might reasonably tweak them.
897 if (placeholder->getKind() == BuiltinType::Overload) return false;
898
899 // If the context potentially accepts unbridged ARC casts, strip
900 // the unbridged cast and add it to the collection for later restoration.
901 if (placeholder->getKind() == BuiltinType::ARCUnbridgedCast &&
902 unbridgedCasts) {
903 unbridgedCasts->save(S, E);
904 return false;
905 }
906
907 // Go ahead and check everything else.
908 ExprResult result = S.CheckPlaceholderExpr(E);
909 if (result.isInvalid())
910 return true;
911
912 E = result.get();
913 return false;
914 }
915
916 // Nothing to do.
917 return false;
918}
919
920/// checkArgPlaceholdersForOverload - Check a set of call operands for
921/// placeholders.
922static bool checkArgPlaceholdersForOverload(Sema &S,
923 MultiExprArg Args,
924 UnbridgedCastsSet &unbridged) {
925 for (unsigned i = 0, e = Args.size(); i != e; ++i)
926 if (checkPlaceholderForOverload(S, Args[i], &unbridged))
927 return true;
928
929 return false;
930}
931
932/// Determine whether the given New declaration is an overload of the
933/// declarations in Old. This routine returns Ovl_Match or Ovl_NonFunction if
934/// New and Old cannot be overloaded, e.g., if New has the same signature as
935/// some function in Old (C++ 1.3.10) or if the Old declarations aren't
936/// functions (or function templates) at all. When it does return Ovl_Match or
937/// Ovl_NonFunction, MatchedDecl will point to the decl that New cannot be
938/// overloaded with. This decl may be a UsingShadowDecl on top of the underlying
939/// declaration.
940///
941/// Example: Given the following input:
942///
943/// void f(int, float); // #1
944/// void f(int, int); // #2
945/// int f(int, int); // #3
946///
947/// When we process #1, there is no previous declaration of "f", so IsOverload
948/// will not be used.
949///
950/// When we process #2, Old contains only the FunctionDecl for #1. By comparing
951/// the parameter types, we see that #1 and #2 are overloaded (since they have
952/// different signatures), so this routine returns Ovl_Overload; MatchedDecl is
953/// unchanged.
954///
955/// When we process #3, Old is an overload set containing #1 and #2. We compare
956/// the signatures of #3 to #1 (they're overloaded, so we do nothing) and then
957/// #3 to #2. Since the signatures of #3 and #2 are identical (return types of
958/// functions are not part of the signature), IsOverload returns Ovl_Match and
959/// MatchedDecl will be set to point to the FunctionDecl for #2.
960///
961/// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced into a class
962/// by a using declaration. The rules for whether to hide shadow declarations
963/// ignore some properties which otherwise figure into a function template's
964/// signature.
965Sema::OverloadKind
966Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old,
967 NamedDecl *&Match, bool NewIsUsingDecl) {
968 for (LookupResult::iterator I = Old.begin(), E = Old.end();
969 I != E; ++I) {
970 NamedDecl *OldD = *I;
971
972 bool OldIsUsingDecl = false;
973 if (isa<UsingShadowDecl>(OldD)) {
974 OldIsUsingDecl = true;
975
976 // We can always introduce two using declarations into the same
977 // context, even if they have identical signatures.
978 if (NewIsUsingDecl) continue;
979
980 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl();
981 }
982
983 // A using-declaration does not conflict with another declaration
984 // if one of them is hidden.
985 if ((OldIsUsingDecl || NewIsUsingDecl) && !isVisible(*I))
986 continue;
987
988 // If either declaration was introduced by a using declaration,
989 // we'll need to use slightly different rules for matching.
990 // Essentially, these rules are the normal rules, except that
991 // function templates hide function templates with different
992 // return types or template parameter lists.
993 bool UseMemberUsingDeclRules =
994 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord() &&
995 !New->getFriendObjectKind();
996
997 if (FunctionDecl *OldF = OldD->getAsFunction()) {
998 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) {
999 if (UseMemberUsingDeclRules && OldIsUsingDecl) {
1000 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I));
1001 continue;
1002 }
1003
1004 if (!isa<FunctionTemplateDecl>(OldD) &&
1005 !shouldLinkPossiblyHiddenDecl(*I, New))
1006 continue;
1007
1008 Match = *I;
1009 return Ovl_Match;
1010 }
1011
1012 // Builtins that have custom typechecking or have a reference should
1013 // not be overloadable or redeclarable.
1014 if (!getASTContext().canBuiltinBeRedeclared(OldF)) {
1015 Match = *I;
1016 return Ovl_NonFunction;
1017 }
1018 } else if (isa<UsingDecl>(OldD) || isa<UsingPackDecl>(OldD)) {
1019 // We can overload with these, which can show up when doing
1020 // redeclaration checks for UsingDecls.
1021 assert(Old.getLookupKind() == LookupUsingDeclName)((Old.getLookupKind() == LookupUsingDeclName) ? static_cast<
void> (0) : __assert_fail ("Old.getLookupKind() == LookupUsingDeclName"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1021, __PRETTY_FUNCTION__))
;
1022 } else if (isa<TagDecl>(OldD)) {
1023 // We can always overload with tags by hiding them.
1024 } else if (auto *UUD = dyn_cast<UnresolvedUsingValueDecl>(OldD)) {
1025 // Optimistically assume that an unresolved using decl will
1026 // overload; if it doesn't, we'll have to diagnose during
1027 // template instantiation.
1028 //
1029 // Exception: if the scope is dependent and this is not a class
1030 // member, the using declaration can only introduce an enumerator.
1031 if (UUD->getQualifier()->isDependent() && !UUD->isCXXClassMember()) {
1032 Match = *I;
1033 return Ovl_NonFunction;
1034 }
1035 } else {
1036 // (C++ 13p1):
1037 // Only function declarations can be overloaded; object and type
1038 // declarations cannot be overloaded.
1039 Match = *I;
1040 return Ovl_NonFunction;
1041 }
1042 }
1043
1044 return Ovl_Overload;
1045}
1046
1047bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old,
1048 bool UseMemberUsingDeclRules, bool ConsiderCudaAttrs) {
1049 // C++ [basic.start.main]p2: This function shall not be overloaded.
1050 if (New->isMain())
1051 return false;
1052
1053 // MSVCRT user defined entry points cannot be overloaded.
1054 if (New->isMSVCRTEntryPoint())
1055 return false;
1056
1057 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate();
1058 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate();
1059
1060 // C++ [temp.fct]p2:
1061 // A function template can be overloaded with other function templates
1062 // and with normal (non-template) functions.
1063 if ((OldTemplate == nullptr) != (NewTemplate == nullptr))
1064 return true;
1065
1066 // Is the function New an overload of the function Old?
1067 QualType OldQType = Context.getCanonicalType(Old->getType());
1068 QualType NewQType = Context.getCanonicalType(New->getType());
1069
1070 // Compare the signatures (C++ 1.3.10) of the two functions to
1071 // determine whether they are overloads. If we find any mismatch
1072 // in the signature, they are overloads.
1073
1074 // If either of these functions is a K&R-style function (no
1075 // prototype), then we consider them to have matching signatures.
1076 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) ||
1077 isa<FunctionNoProtoType>(NewQType.getTypePtr()))
1078 return false;
1079
1080 const FunctionProtoType *OldType = cast<FunctionProtoType>(OldQType);
1081 const FunctionProtoType *NewType = cast<FunctionProtoType>(NewQType);
1082
1083 // The signature of a function includes the types of its
1084 // parameters (C++ 1.3.10), which includes the presence or absence
1085 // of the ellipsis; see C++ DR 357).
1086 if (OldQType != NewQType &&
1087 (OldType->getNumParams() != NewType->getNumParams() ||
1088 OldType->isVariadic() != NewType->isVariadic() ||
1089 !FunctionParamTypesAreEqual(OldType, NewType)))
1090 return true;
1091
1092 // C++ [temp.over.link]p4:
1093 // The signature of a function template consists of its function
1094 // signature, its return type and its template parameter list. The names
1095 // of the template parameters are significant only for establishing the
1096 // relationship between the template parameters and the rest of the
1097 // signature.
1098 //
1099 // We check the return type and template parameter lists for function
1100 // templates first; the remaining checks follow.
1101 //
1102 // However, we don't consider either of these when deciding whether
1103 // a member introduced by a shadow declaration is hidden.
1104 if (!UseMemberUsingDeclRules && NewTemplate &&
1105 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
1106 OldTemplate->getTemplateParameters(),
1107 false, TPL_TemplateMatch) ||
1108 !Context.hasSameType(Old->getDeclaredReturnType(),
1109 New->getDeclaredReturnType())))
1110 return true;
1111
1112 // If the function is a class member, its signature includes the
1113 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself.
1114 //
1115 // As part of this, also check whether one of the member functions
1116 // is static, in which case they are not overloads (C++
1117 // 13.1p2). While not part of the definition of the signature,
1118 // this check is important to determine whether these functions
1119 // can be overloaded.
1120 CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old);
1121 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New);
1122 if (OldMethod && NewMethod &&
1123 !OldMethod->isStatic() && !NewMethod->isStatic()) {
1124 if (OldMethod->getRefQualifier() != NewMethod->getRefQualifier()) {
1125 if (!UseMemberUsingDeclRules &&
1126 (OldMethod->getRefQualifier() == RQ_None ||
1127 NewMethod->getRefQualifier() == RQ_None)) {
1128 // C++0x [over.load]p2:
1129 // - Member function declarations with the same name and the same
1130 // parameter-type-list as well as member function template
1131 // declarations with the same name, the same parameter-type-list, and
1132 // the same template parameter lists cannot be overloaded if any of
1133 // them, but not all, have a ref-qualifier (8.3.5).
1134 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload)
1135 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier();
1136 Diag(OldMethod->getLocation(), diag::note_previous_declaration);
1137 }
1138 return true;
1139 }
1140
1141 // We may not have applied the implicit const for a constexpr member
1142 // function yet (because we haven't yet resolved whether this is a static
1143 // or non-static member function). Add it now, on the assumption that this
1144 // is a redeclaration of OldMethod.
1145 unsigned OldQuals = OldMethod->getTypeQualifiers();
1146 unsigned NewQuals = NewMethod->getTypeQualifiers();
1147 if (!getLangOpts().CPlusPlus14 && NewMethod->isConstexpr() &&
1148 !isa<CXXConstructorDecl>(NewMethod))
1149 NewQuals |= Qualifiers::Const;
1150
1151 // We do not allow overloading based off of '__restrict'.
1152 OldQuals &= ~Qualifiers::Restrict;
1153 NewQuals &= ~Qualifiers::Restrict;
1154 if (OldQuals != NewQuals)
1155 return true;
1156 }
1157
1158 // Though pass_object_size is placed on parameters and takes an argument, we
1159 // consider it to be a function-level modifier for the sake of function
1160 // identity. Either the function has one or more parameters with
1161 // pass_object_size or it doesn't.
1162 if (functionHasPassObjectSizeParams(New) !=
1163 functionHasPassObjectSizeParams(Old))
1164 return true;
1165
1166 // enable_if attributes are an order-sensitive part of the signature.
1167 for (specific_attr_iterator<EnableIfAttr>
1168 NewI = New->specific_attr_begin<EnableIfAttr>(),
1169 NewE = New->specific_attr_end<EnableIfAttr>(),
1170 OldI = Old->specific_attr_begin<EnableIfAttr>(),
1171 OldE = Old->specific_attr_end<EnableIfAttr>();
1172 NewI != NewE || OldI != OldE; ++NewI, ++OldI) {
1173 if (NewI == NewE || OldI == OldE)
1174 return true;
1175 llvm::FoldingSetNodeID NewID, OldID;
1176 NewI->getCond()->Profile(NewID, Context, true);
1177 OldI->getCond()->Profile(OldID, Context, true);
1178 if (NewID != OldID)
1179 return true;
1180 }
1181
1182 if (getLangOpts().CUDA && ConsiderCudaAttrs) {
1183 // Don't allow overloading of destructors. (In theory we could, but it
1184 // would be a giant change to clang.)
1185 if (isa<CXXDestructorDecl>(New))
1186 return false;
1187
1188 CUDAFunctionTarget NewTarget = IdentifyCUDATarget(New),
1189 OldTarget = IdentifyCUDATarget(Old);
1190 if (NewTarget == CFT_InvalidTarget)
1191 return false;
1192
1193 assert((OldTarget != CFT_InvalidTarget) && "Unexpected invalid target.")(((OldTarget != CFT_InvalidTarget) && "Unexpected invalid target."
) ? static_cast<void> (0) : __assert_fail ("(OldTarget != CFT_InvalidTarget) && \"Unexpected invalid target.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1193, __PRETTY_FUNCTION__))
;
1194
1195 // Allow overloading of functions with same signature and different CUDA
1196 // target attributes.
1197 return NewTarget != OldTarget;
1198 }
1199
1200 // The signatures match; this is not an overload.
1201 return false;
1202}
1203
1204/// Checks availability of the function depending on the current
1205/// function context. Inside an unavailable function, unavailability is ignored.
1206///
1207/// \returns true if \arg FD is unavailable and current context is inside
1208/// an available function, false otherwise.
1209bool Sema::isFunctionConsideredUnavailable(FunctionDecl *FD) {
1210 if (!FD->isUnavailable())
1211 return false;
1212
1213 // Walk up the context of the caller.
1214 Decl *C = cast<Decl>(CurContext);
1215 do {
1216 if (C->isUnavailable())
1217 return false;
1218 } while ((C = cast_or_null<Decl>(C->getDeclContext())));
1219 return true;
1220}
1221
1222/// Tries a user-defined conversion from From to ToType.
1223///
1224/// Produces an implicit conversion sequence for when a standard conversion
1225/// is not an option. See TryImplicitConversion for more information.
1226static ImplicitConversionSequence
1227TryUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
1228 bool SuppressUserConversions,
1229 bool AllowExplicit,
1230 bool InOverloadResolution,
1231 bool CStyle,
1232 bool AllowObjCWritebackConversion,
1233 bool AllowObjCConversionOnExplicit) {
1234 ImplicitConversionSequence ICS;
1235
1236 if (SuppressUserConversions) {
1237 // We're not in the case above, so there is no conversion that
1238 // we can perform.
1239 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1240 return ICS;
1241 }
1242
1243 // Attempt user-defined conversion.
1244 OverloadCandidateSet Conversions(From->getExprLoc(),
1245 OverloadCandidateSet::CSK_Normal);
1246 switch (IsUserDefinedConversion(S, From, ToType, ICS.UserDefined,
1247 Conversions, AllowExplicit,
1248 AllowObjCConversionOnExplicit)) {
1249 case OR_Success:
1250 case OR_Deleted:
1251 ICS.setUserDefined();
1252 // C++ [over.ics.user]p4:
1253 // A conversion of an expression of class type to the same class
1254 // type is given Exact Match rank, and a conversion of an
1255 // expression of class type to a base class of that type is
1256 // given Conversion rank, in spite of the fact that a copy
1257 // constructor (i.e., a user-defined conversion function) is
1258 // called for those cases.
1259 if (CXXConstructorDecl *Constructor
1260 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) {
1261 QualType FromCanon
1262 = S.Context.getCanonicalType(From->getType().getUnqualifiedType());
1263 QualType ToCanon
1264 = S.Context.getCanonicalType(ToType).getUnqualifiedType();
1265 if (Constructor->isCopyConstructor() &&
1266 (FromCanon == ToCanon ||
1267 S.IsDerivedFrom(From->getBeginLoc(), FromCanon, ToCanon))) {
1268 // Turn this into a "standard" conversion sequence, so that it
1269 // gets ranked with standard conversion sequences.
1270 DeclAccessPair Found = ICS.UserDefined.FoundConversionFunction;
1271 ICS.setStandard();
1272 ICS.Standard.setAsIdentityConversion();
1273 ICS.Standard.setFromType(From->getType());
1274 ICS.Standard.setAllToTypes(ToType);
1275 ICS.Standard.CopyConstructor = Constructor;
1276 ICS.Standard.FoundCopyConstructor = Found;
1277 if (ToCanon != FromCanon)
1278 ICS.Standard.Second = ICK_Derived_To_Base;
1279 }
1280 }
1281 break;
1282
1283 case OR_Ambiguous:
1284 ICS.setAmbiguous();
1285 ICS.Ambiguous.setFromType(From->getType());
1286 ICS.Ambiguous.setToType(ToType);
1287 for (OverloadCandidateSet::iterator Cand = Conversions.begin();
1288 Cand != Conversions.end(); ++Cand)
1289 if (Cand->Viable)
1290 ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
1291 break;
1292
1293 // Fall through.
1294 case OR_No_Viable_Function:
1295 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1296 break;
1297 }
1298
1299 return ICS;
1300}
1301
1302/// TryImplicitConversion - Attempt to perform an implicit conversion
1303/// from the given expression (Expr) to the given type (ToType). This
1304/// function returns an implicit conversion sequence that can be used
1305/// to perform the initialization. Given
1306///
1307/// void f(float f);
1308/// void g(int i) { f(i); }
1309///
1310/// this routine would produce an implicit conversion sequence to
1311/// describe the initialization of f from i, which will be a standard
1312/// conversion sequence containing an lvalue-to-rvalue conversion (C++
1313/// 4.1) followed by a floating-integral conversion (C++ 4.9).
1314//
1315/// Note that this routine only determines how the conversion can be
1316/// performed; it does not actually perform the conversion. As such,
1317/// it will not produce any diagnostics if no conversion is available,
1318/// but will instead return an implicit conversion sequence of kind
1319/// "BadConversion".
1320///
1321/// If @p SuppressUserConversions, then user-defined conversions are
1322/// not permitted.
1323/// If @p AllowExplicit, then explicit user-defined conversions are
1324/// permitted.
1325///
1326/// \param AllowObjCWritebackConversion Whether we allow the Objective-C
1327/// writeback conversion, which allows __autoreleasing id* parameters to
1328/// be initialized with __strong id* or __weak id* arguments.
1329static ImplicitConversionSequence
1330TryImplicitConversion(Sema &S, Expr *From, QualType ToType,
1331 bool SuppressUserConversions,
1332 bool AllowExplicit,
1333 bool InOverloadResolution,
1334 bool CStyle,
1335 bool AllowObjCWritebackConversion,
1336 bool AllowObjCConversionOnExplicit) {
1337 ImplicitConversionSequence ICS;
1338 if (IsStandardConversion(S, From, ToType, InOverloadResolution,
1339 ICS.Standard, CStyle, AllowObjCWritebackConversion)){
1340 ICS.setStandard();
1341 return ICS;
1342 }
1343
1344 if (!S.getLangOpts().CPlusPlus) {
1345 ICS.setBad(BadConversionSequence::no_conversion, From, ToType);
1346 return ICS;
1347 }
1348
1349 // C++ [over.ics.user]p4:
1350 // A conversion of an expression of class type to the same class
1351 // type is given Exact Match rank, and a conversion of an
1352 // expression of class type to a base class of that type is
1353 // given Conversion rank, in spite of the fact that a copy/move
1354 // constructor (i.e., a user-defined conversion function) is
1355 // called for those cases.
1356 QualType FromType = From->getType();
1357 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() &&
1358 (S.Context.hasSameUnqualifiedType(FromType, ToType) ||
1359 S.IsDerivedFrom(From->getBeginLoc(), FromType, ToType))) {
1360 ICS.setStandard();
1361 ICS.Standard.setAsIdentityConversion();
1362 ICS.Standard.setFromType(FromType);
1363 ICS.Standard.setAllToTypes(ToType);
1364
1365 // We don't actually check at this point whether there is a valid
1366 // copy/move constructor, since overloading just assumes that it
1367 // exists. When we actually perform initialization, we'll find the
1368 // appropriate constructor to copy the returned object, if needed.
1369 ICS.Standard.CopyConstructor = nullptr;
1370
1371 // Determine whether this is considered a derived-to-base conversion.
1372 if (!S.Context.hasSameUnqualifiedType(FromType, ToType))
1373 ICS.Standard.Second = ICK_Derived_To_Base;
1374
1375 return ICS;
1376 }
1377
1378 return TryUserDefinedConversion(S, From, ToType, SuppressUserConversions,
1379 AllowExplicit, InOverloadResolution, CStyle,
1380 AllowObjCWritebackConversion,
1381 AllowObjCConversionOnExplicit);
1382}
1383
1384ImplicitConversionSequence
1385Sema::TryImplicitConversion(Expr *From, QualType ToType,
1386 bool SuppressUserConversions,
1387 bool AllowExplicit,
1388 bool InOverloadResolution,
1389 bool CStyle,
1390 bool AllowObjCWritebackConversion) {
1391 return ::TryImplicitConversion(*this, From, ToType,
1392 SuppressUserConversions, AllowExplicit,
1393 InOverloadResolution, CStyle,
1394 AllowObjCWritebackConversion,
1395 /*AllowObjCConversionOnExplicit=*/false);
1396}
1397
1398/// PerformImplicitConversion - Perform an implicit conversion of the
1399/// expression From to the type ToType. Returns the
1400/// converted expression. Flavor is the kind of conversion we're
1401/// performing, used in the error message. If @p AllowExplicit,
1402/// explicit user-defined conversions are permitted.
1403ExprResult
1404Sema::PerformImplicitConversion(Expr *From, QualType ToType,
1405 AssignmentAction Action, bool AllowExplicit) {
1406 ImplicitConversionSequence ICS;
1407 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS);
1408}
1409
1410ExprResult
1411Sema::PerformImplicitConversion(Expr *From, QualType ToType,
1412 AssignmentAction Action, bool AllowExplicit,
1413 ImplicitConversionSequence& ICS) {
1414 if (checkPlaceholderForOverload(*this, From))
1415 return ExprError();
1416
1417 // Objective-C ARC: Determine whether we will allow the writeback conversion.
1418 bool AllowObjCWritebackConversion
1419 = getLangOpts().ObjCAutoRefCount &&
1420 (Action == AA_Passing || Action == AA_Sending);
1421 if (getLangOpts().ObjC1)
1422 CheckObjCBridgeRelatedConversions(From->getBeginLoc(), ToType,
1423 From->getType(), From);
1424 ICS = ::TryImplicitConversion(*this, From, ToType,
1425 /*SuppressUserConversions=*/false,
1426 AllowExplicit,
1427 /*InOverloadResolution=*/false,
1428 /*CStyle=*/false,
1429 AllowObjCWritebackConversion,
1430 /*AllowObjCConversionOnExplicit=*/false);
1431 return PerformImplicitConversion(From, ToType, ICS, Action);
1432}
1433
1434/// Determine whether the conversion from FromType to ToType is a valid
1435/// conversion that strips "noexcept" or "noreturn" off the nested function
1436/// type.
1437bool Sema::IsFunctionConversion(QualType FromType, QualType ToType,
1438 QualType &ResultTy) {
1439 if (Context.hasSameUnqualifiedType(FromType, ToType))
1440 return false;
1441
1442 // Permit the conversion F(t __attribute__((noreturn))) -> F(t)
1443 // or F(t noexcept) -> F(t)
1444 // where F adds one of the following at most once:
1445 // - a pointer
1446 // - a member pointer
1447 // - a block pointer
1448 // Changes here need matching changes in FindCompositePointerType.
1449 CanQualType CanTo = Context.getCanonicalType(ToType);
1450 CanQualType CanFrom = Context.getCanonicalType(FromType);
1451 Type::TypeClass TyClass = CanTo->getTypeClass();
1452 if (TyClass != CanFrom->getTypeClass()) return false;
1453 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) {
1454 if (TyClass == Type::Pointer) {
1455 CanTo = CanTo.getAs<PointerType>()->getPointeeType();
1456 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType();
1457 } else if (TyClass == Type::BlockPointer) {
1458 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType();
1459 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType();
1460 } else if (TyClass == Type::MemberPointer) {
1461 auto ToMPT = CanTo.getAs<MemberPointerType>();
1462 auto FromMPT = CanFrom.getAs<MemberPointerType>();
1463 // A function pointer conversion cannot change the class of the function.
1464 if (ToMPT->getClass() != FromMPT->getClass())
1465 return false;
1466 CanTo = ToMPT->getPointeeType();
1467 CanFrom = FromMPT->getPointeeType();
1468 } else {
1469 return false;
1470 }
1471
1472 TyClass = CanTo->getTypeClass();
1473 if (TyClass != CanFrom->getTypeClass()) return false;
1474 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto)
1475 return false;
1476 }
1477
1478 const auto *FromFn = cast<FunctionType>(CanFrom);
1479 FunctionType::ExtInfo FromEInfo = FromFn->getExtInfo();
1480
1481 const auto *ToFn = cast<FunctionType>(CanTo);
1482 FunctionType::ExtInfo ToEInfo = ToFn->getExtInfo();
1483
1484 bool Changed = false;
1485
1486 // Drop 'noreturn' if not present in target type.
1487 if (FromEInfo.getNoReturn() && !ToEInfo.getNoReturn()) {
1488 FromFn = Context.adjustFunctionType(FromFn, FromEInfo.withNoReturn(false));
1489 Changed = true;
1490 }
1491
1492 // Drop 'noexcept' if not present in target type.
1493 if (const auto *FromFPT = dyn_cast<FunctionProtoType>(FromFn)) {
1494 const auto *ToFPT = cast<FunctionProtoType>(ToFn);
1495 if (FromFPT->isNothrow() && !ToFPT->isNothrow()) {
1496 FromFn = cast<FunctionType>(
1497 Context.getFunctionTypeWithExceptionSpec(QualType(FromFPT, 0),
1498 EST_None)
1499 .getTypePtr());
1500 Changed = true;
1501 }
1502
1503 // Convert FromFPT's ExtParameterInfo if necessary. The conversion is valid
1504 // only if the ExtParameterInfo lists of the two function prototypes can be
1505 // merged and the merged list is identical to ToFPT's ExtParameterInfo list.
1506 SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
1507 bool CanUseToFPT, CanUseFromFPT;
1508 if (Context.mergeExtParameterInfo(ToFPT, FromFPT, CanUseToFPT,
1509 CanUseFromFPT, NewParamInfos) &&
1510 CanUseToFPT && !CanUseFromFPT) {
1511 FunctionProtoType::ExtProtoInfo ExtInfo = FromFPT->getExtProtoInfo();
1512 ExtInfo.ExtParameterInfos =
1513 NewParamInfos.empty() ? nullptr : NewParamInfos.data();
1514 QualType QT = Context.getFunctionType(FromFPT->getReturnType(),
1515 FromFPT->getParamTypes(), ExtInfo);
1516 FromFn = QT->getAs<FunctionType>();
1517 Changed = true;
1518 }
1519 }
1520
1521 if (!Changed)
1522 return false;
1523
1524 assert(QualType(FromFn, 0).isCanonical())((QualType(FromFn, 0).isCanonical()) ? static_cast<void>
(0) : __assert_fail ("QualType(FromFn, 0).isCanonical()", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1524, __PRETTY_FUNCTION__))
;
1525 if (QualType(FromFn, 0) != CanTo) return false;
1526
1527 ResultTy = ToType;
1528 return true;
1529}
1530
1531/// Determine whether the conversion from FromType to ToType is a valid
1532/// vector conversion.
1533///
1534/// \param ICK Will be set to the vector conversion kind, if this is a vector
1535/// conversion.
1536static bool IsVectorConversion(Sema &S, QualType FromType,
1537 QualType ToType, ImplicitConversionKind &ICK) {
1538 // We need at least one of these types to be a vector type to have a vector
1539 // conversion.
1540 if (!ToType->isVectorType() && !FromType->isVectorType())
1541 return false;
1542
1543 // Identical types require no conversions.
1544 if (S.Context.hasSameUnqualifiedType(FromType, ToType))
1545 return false;
1546
1547 // There are no conversions between extended vector types, only identity.
1548 if (ToType->isExtVectorType()) {
1549 // There are no conversions between extended vector types other than the
1550 // identity conversion.
1551 if (FromType->isExtVectorType())
1552 return false;
1553
1554 // Vector splat from any arithmetic type to a vector.
1555 if (FromType->isArithmeticType()) {
1556 ICK = ICK_Vector_Splat;
1557 return true;
1558 }
1559 }
1560
1561 // We can perform the conversion between vector types in the following cases:
1562 // 1)vector types are equivalent AltiVec and GCC vector types
1563 // 2)lax vector conversions are permitted and the vector types are of the
1564 // same size
1565 if (ToType->isVectorType() && FromType->isVectorType()) {
1566 if (S.Context.areCompatibleVectorTypes(FromType, ToType) ||
1567 S.isLaxVectorConversion(FromType, ToType)) {
1568 ICK = ICK_Vector_Conversion;
1569 return true;
1570 }
1571 }
1572
1573 return false;
1574}
1575
1576static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType,
1577 bool InOverloadResolution,
1578 StandardConversionSequence &SCS,
1579 bool CStyle);
1580
1581/// IsStandardConversion - Determines whether there is a standard
1582/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the
1583/// expression From to the type ToType. Standard conversion sequences
1584/// only consider non-class types; for conversions that involve class
1585/// types, use TryImplicitConversion. If a conversion exists, SCS will
1586/// contain the standard conversion sequence required to perform this
1587/// conversion and this routine will return true. Otherwise, this
1588/// routine will return false and the value of SCS is unspecified.
1589static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
1590 bool InOverloadResolution,
1591 StandardConversionSequence &SCS,
1592 bool CStyle,
1593 bool AllowObjCWritebackConversion) {
1594 QualType FromType = From->getType();
1595
1596 // Standard conversions (C++ [conv])
1597 SCS.setAsIdentityConversion();
1598 SCS.IncompatibleObjC = false;
1599 SCS.setFromType(FromType);
1600 SCS.CopyConstructor = nullptr;
1601
1602 // There are no standard conversions for class types in C++, so
1603 // abort early. When overloading in C, however, we do permit them.
1604 if (S.getLangOpts().CPlusPlus &&
1605 (FromType->isRecordType() || ToType->isRecordType()))
1606 return false;
1607
1608 // The first conversion can be an lvalue-to-rvalue conversion,
1609 // array-to-pointer conversion, or function-to-pointer conversion
1610 // (C++ 4p1).
1611
1612 if (FromType == S.Context.OverloadTy) {
1613 DeclAccessPair AccessPair;
1614 if (FunctionDecl *Fn
1615 = S.ResolveAddressOfOverloadedFunction(From, ToType, false,
1616 AccessPair)) {
1617 // We were able to resolve the address of the overloaded function,
1618 // so we can convert to the type of that function.
1619 FromType = Fn->getType();
1620 SCS.setFromType(FromType);
1621
1622 // we can sometimes resolve &foo<int> regardless of ToType, so check
1623 // if the type matches (identity) or we are converting to bool
1624 if (!S.Context.hasSameUnqualifiedType(
1625 S.ExtractUnqualifiedFunctionType(ToType), FromType)) {
1626 QualType resultTy;
1627 // if the function type matches except for [[noreturn]], it's ok
1628 if (!S.IsFunctionConversion(FromType,
1629 S.ExtractUnqualifiedFunctionType(ToType), resultTy))
1630 // otherwise, only a boolean conversion is standard
1631 if (!ToType->isBooleanType())
1632 return false;
1633 }
1634
1635 // Check if the "from" expression is taking the address of an overloaded
1636 // function and recompute the FromType accordingly. Take advantage of the
1637 // fact that non-static member functions *must* have such an address-of
1638 // expression.
1639 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn);
1640 if (Method && !Method->isStatic()) {
1641 assert(isa<UnaryOperator>(From->IgnoreParens()) &&((isa<UnaryOperator>(From->IgnoreParens()) &&
"Non-unary operator on non-static member address") ? static_cast
<void> (0) : __assert_fail ("isa<UnaryOperator>(From->IgnoreParens()) && \"Non-unary operator on non-static member address\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1642, __PRETTY_FUNCTION__))
1642 "Non-unary operator on non-static member address")((isa<UnaryOperator>(From->IgnoreParens()) &&
"Non-unary operator on non-static member address") ? static_cast
<void> (0) : __assert_fail ("isa<UnaryOperator>(From->IgnoreParens()) && \"Non-unary operator on non-static member address\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1642, __PRETTY_FUNCTION__))
;
1643 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode()((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator on non-static member address"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator on non-static member address\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1645, __PRETTY_FUNCTION__))
1644 == UO_AddrOf &&((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator on non-static member address"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator on non-static member address\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1645, __PRETTY_FUNCTION__))
1645 "Non-address-of operator on non-static member address")((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator on non-static member address"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator on non-static member address\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1645, __PRETTY_FUNCTION__))
;
1646 const Type *ClassType
1647 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr();
1648 FromType = S.Context.getMemberPointerType(FromType, ClassType);
1649 } else if (isa<UnaryOperator>(From->IgnoreParens())) {
1650 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() ==((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator for overloaded function expression"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator for overloaded function expression\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1652, __PRETTY_FUNCTION__))
1651 UO_AddrOf &&((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator for overloaded function expression"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator for overloaded function expression\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1652, __PRETTY_FUNCTION__))
1652 "Non-address-of operator for overloaded function expression")((cast<UnaryOperator>(From->IgnoreParens())->getOpcode
() == UO_AddrOf && "Non-address-of operator for overloaded function expression"
) ? static_cast<void> (0) : __assert_fail ("cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == UO_AddrOf && \"Non-address-of operator for overloaded function expression\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1652, __PRETTY_FUNCTION__))
;
1653 FromType = S.Context.getPointerType(FromType);
1654 }
1655
1656 // Check that we've computed the proper type after overload resolution.
1657 // FIXME: FixOverloadedFunctionReference has side-effects; we shouldn't
1658 // be calling it from within an NDEBUG block.
1659 assert(S.Context.hasSameType(((S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference
(From, AccessPair, Fn)->getType())) ? static_cast<void>
(0) : __assert_fail ("S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1661, __PRETTY_FUNCTION__))
1660 FromType,((S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference
(From, AccessPair, Fn)->getType())) ? static_cast<void>
(0) : __assert_fail ("S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1661, __PRETTY_FUNCTION__))
1661 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType()))((S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference
(From, AccessPair, Fn)->getType())) ? static_cast<void>
(0) : __assert_fail ("S.Context.hasSameType( FromType, S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 1661, __PRETTY_FUNCTION__))
;
1662 } else {
1663 return false;
1664 }
1665 }
1666 // Lvalue-to-rvalue conversion (C++11 4.1):
1667 // A glvalue (3.10) of a non-function, non-array type T can
1668 // be converted to a prvalue.
1669 bool argIsLValue = From->isGLValue();
1670 if (argIsLValue &&
1671 !FromType->isFunctionType() && !FromType->isArrayType() &&
1672 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) {
1673 SCS.First = ICK_Lvalue_To_Rvalue;
1674
1675 // C11 6.3.2.1p2:
1676 // ... if the lvalue has atomic type, the value has the non-atomic version
1677 // of the type of the lvalue ...
1678 if (const AtomicType *Atomic = FromType->getAs<AtomicType>())
1679 FromType = Atomic->getValueType();
1680
1681 // If T is a non-class type, the type of the rvalue is the
1682 // cv-unqualified version of T. Otherwise, the type of the rvalue
1683 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we
1684 // just strip the qualifiers because they don't matter.
1685 FromType = FromType.getUnqualifiedType();
1686 } else if (FromType->isArrayType()) {
1687 // Array-to-pointer conversion (C++ 4.2)
1688 SCS.First = ICK_Array_To_Pointer;
1689
1690 // An lvalue or rvalue of type "array of N T" or "array of unknown
1691 // bound of T" can be converted to an rvalue of type "pointer to
1692 // T" (C++ 4.2p1).
1693 FromType = S.Context.getArrayDecayedType(FromType);
1694
1695 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) {
1696 // This conversion is deprecated in C++03 (D.4)
1697 SCS.DeprecatedStringLiteralToCharPtr = true;
1698
1699 // For the purpose of ranking in overload resolution
1700 // (13.3.3.1.1), this conversion is considered an
1701 // array-to-pointer conversion followed by a qualification
1702 // conversion (4.4). (C++ 4.2p2)
1703 SCS.Second = ICK_Identity;
1704 SCS.Third = ICK_Qualification;
1705 SCS.QualificationIncludesObjCLifetime = false;
1706 SCS.setAllToTypes(FromType);
1707 return true;
1708 }
1709 } else if (FromType->isFunctionType() && argIsLValue) {
1710 // Function-to-pointer conversion (C++ 4.3).
1711 SCS.First = ICK_Function_To_Pointer;
1712
1713 if (auto *DRE = dyn_cast<DeclRefExpr>(From->IgnoreParenCasts()))
1714 if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl()))
1715 if (!S.checkAddressOfFunctionIsAvailable(FD))
1716 return false;
1717
1718 // An lvalue of function type T can be converted to an rvalue of
1719 // type "pointer to T." The result is a pointer to the
1720 // function. (C++ 4.3p1).
1721 FromType = S.Context.getPointerType(FromType);
1722 } else {
1723 // We don't require any conversions for the first step.
1724 SCS.First = ICK_Identity;
1725 }
1726 SCS.setToType(0, FromType);
1727
1728 // The second conversion can be an integral promotion, floating
1729 // point promotion, integral conversion, floating point conversion,
1730 // floating-integral conversion, pointer conversion,
1731 // pointer-to-member conversion, or boolean conversion (C++ 4p1).
1732 // For overloading in C, this can also be a "compatible-type"
1733 // conversion.
1734 bool IncompatibleObjC = false;
1735 ImplicitConversionKind SecondICK = ICK_Identity;
1736 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) {
1737 // The unqualified versions of the types are the same: there's no
1738 // conversion to do.
1739 SCS.Second = ICK_Identity;
1740 } else if (S.IsIntegralPromotion(From, FromType, ToType)) {
1741 // Integral promotion (C++ 4.5).
1742 SCS.Second = ICK_Integral_Promotion;
1743 FromType = ToType.getUnqualifiedType();
1744 } else if (S.IsFloatingPointPromotion(FromType, ToType)) {
1745 // Floating point promotion (C++ 4.6).
1746 SCS.Second = ICK_Floating_Promotion;
1747 FromType = ToType.getUnqualifiedType();
1748 } else if (S.IsComplexPromotion(FromType, ToType)) {
1749 // Complex promotion (Clang extension)
1750 SCS.Second = ICK_Complex_Promotion;
1751 FromType = ToType.getUnqualifiedType();
1752 } else if (ToType->isBooleanType() &&
1753 (FromType->isArithmeticType() ||
1754 FromType->isAnyPointerType() ||
1755 FromType->isBlockPointerType() ||
1756 FromType->isMemberPointerType() ||
1757 FromType->isNullPtrType())) {
1758 // Boolean conversions (C++ 4.12).
1759 SCS.Second = ICK_Boolean_Conversion;
1760 FromType = S.Context.BoolTy;
1761 } else if (FromType->isIntegralOrUnscopedEnumerationType() &&
1762 ToType->isIntegralType(S.Context)) {
1763 // Integral conversions (C++ 4.7).
1764 SCS.Second = ICK_Integral_Conversion;
1765 FromType = ToType.getUnqualifiedType();
1766 } else if (FromType->isAnyComplexType() && ToType->isAnyComplexType()) {
1767 // Complex conversions (C99 6.3.1.6)
1768 SCS.Second = ICK_Complex_Conversion;
1769 FromType = ToType.getUnqualifiedType();
1770 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) ||
1771 (ToType->isAnyComplexType() && FromType->isArithmeticType())) {
1772 // Complex-real conversions (C99 6.3.1.7)
1773 SCS.Second = ICK_Complex_Real;
1774 FromType = ToType.getUnqualifiedType();
1775 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) {
1776 // FIXME: disable conversions between long double and __float128 if
1777 // their representation is different until there is back end support
1778 // We of course allow this conversion if long double is really double.
1779 if (&S.Context.getFloatTypeSemantics(FromType) !=
1780 &S.Context.getFloatTypeSemantics(ToType)) {
1781 bool Float128AndLongDouble = ((FromType == S.Context.Float128Ty &&
1782 ToType == S.Context.LongDoubleTy) ||
1783 (FromType == S.Context.LongDoubleTy &&
1784 ToType == S.Context.Float128Ty));
1785 if (Float128AndLongDouble &&
1786 (&S.Context.getFloatTypeSemantics(S.Context.LongDoubleTy) ==
1787 &llvm::APFloat::PPCDoubleDouble()))
1788 return false;
1789 }
1790 // Floating point conversions (C++ 4.8).
1791 SCS.Second = ICK_Floating_Conversion;
1792 FromType = ToType.getUnqualifiedType();
1793 } else if ((FromType->isRealFloatingType() &&
1794 ToType->isIntegralType(S.Context)) ||
1795 (FromType->isIntegralOrUnscopedEnumerationType() &&
1796 ToType->isRealFloatingType())) {
1797 // Floating-integral conversions (C++ 4.9).
1798 SCS.Second = ICK_Floating_Integral;
1799 FromType = ToType.getUnqualifiedType();
1800 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) {
1801 SCS.Second = ICK_Block_Pointer_Conversion;
1802 } else if (AllowObjCWritebackConversion &&
1803 S.isObjCWritebackConversion(FromType, ToType, FromType)) {
1804 SCS.Second = ICK_Writeback_Conversion;
1805 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution,
1806 FromType, IncompatibleObjC)) {
1807 // Pointer conversions (C++ 4.10).
1808 SCS.Second = ICK_Pointer_Conversion;
1809 SCS.IncompatibleObjC = IncompatibleObjC;
1810 FromType = FromType.getUnqualifiedType();
1811 } else if (S.IsMemberPointerConversion(From, FromType, ToType,
1812 InOverloadResolution, FromType)) {
1813 // Pointer to member conversions (4.11).
1814 SCS.Second = ICK_Pointer_Member;
1815 } else if (IsVectorConversion(S, FromType, ToType, SecondICK)) {
1816 SCS.Second = SecondICK;
1817 FromType = ToType.getUnqualifiedType();
1818 } else if (!S.getLangOpts().CPlusPlus &&
1819 S.Context.typesAreCompatible(ToType, FromType)) {
1820 // Compatible conversions (Clang extension for C function overloading)
1821 SCS.Second = ICK_Compatible_Conversion;
1822 FromType = ToType.getUnqualifiedType();
1823 } else if (IsTransparentUnionStandardConversion(S, From, ToType,
1824 InOverloadResolution,
1825 SCS, CStyle)) {
1826 SCS.Second = ICK_TransparentUnionConversion;
1827 FromType = ToType;
1828 } else if (tryAtomicConversion(S, From, ToType, InOverloadResolution, SCS,
1829 CStyle)) {
1830 // tryAtomicConversion has updated the standard conversion sequence
1831 // appropriately.
1832 return true;
1833 } else if (ToType->isEventT() &&
1834 From->isIntegerConstantExpr(S.getASTContext()) &&
1835 From->EvaluateKnownConstInt(S.getASTContext()) == 0) {
1836 SCS.Second = ICK_Zero_Event_Conversion;
1837 FromType = ToType;
1838 } else if (ToType->isQueueT() &&
1839 From->isIntegerConstantExpr(S.getASTContext()) &&
1840 (From->EvaluateKnownConstInt(S.getASTContext()) == 0)) {
1841 SCS.Second = ICK_Zero_Queue_Conversion;
1842 FromType = ToType;
1843 } else {
1844 // No second conversion required.
1845 SCS.Second = ICK_Identity;
1846 }
1847 SCS.setToType(1, FromType);
1848
1849 // The third conversion can be a function pointer conversion or a
1850 // qualification conversion (C++ [conv.fctptr], [conv.qual]).
1851 bool ObjCLifetimeConversion;
1852 if (S.IsFunctionConversion(FromType, ToType, FromType)) {
1853 // Function pointer conversions (removing 'noexcept') including removal of
1854 // 'noreturn' (Clang extension).
1855 SCS.Third = ICK_Function_Conversion;
1856 } else if (S.IsQualificationConversion(FromType, ToType, CStyle,
1857 ObjCLifetimeConversion)) {
1858 SCS.Third = ICK_Qualification;
1859 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion;
1860 FromType = ToType;
1861 } else {
1862 // No conversion required
1863 SCS.Third = ICK_Identity;
1864 }
1865
1866 // C++ [over.best.ics]p6:
1867 // [...] Any difference in top-level cv-qualification is
1868 // subsumed by the initialization itself and does not constitute
1869 // a conversion. [...]
1870 QualType CanonFrom = S.Context.getCanonicalType(FromType);
1871 QualType CanonTo = S.Context.getCanonicalType(ToType);
1872 if (CanonFrom.getLocalUnqualifiedType()
1873 == CanonTo.getLocalUnqualifiedType() &&
1874 CanonFrom.getLocalQualifiers() != CanonTo.getLocalQualifiers()) {
1875 FromType = ToType;
1876 CanonFrom = CanonTo;
1877 }
1878
1879 SCS.setToType(2, FromType);
1880
1881 if (CanonFrom == CanonTo)
1882 return true;
1883
1884 // If we have not converted the argument type to the parameter type,
1885 // this is a bad conversion sequence, unless we're resolving an overload in C.
1886 if (S.getLangOpts().CPlusPlus || !InOverloadResolution)
1887 return false;
1888
1889 ExprResult ER = ExprResult{From};
1890 Sema::AssignConvertType Conv =
1891 S.CheckSingleAssignmentConstraints(ToType, ER,
1892 /*Diagnose=*/false,
1893 /*DiagnoseCFAudited=*/false,
1894 /*ConvertRHS=*/false);
1895 ImplicitConversionKind SecondConv;
1896 switch (Conv) {
1897 case Sema::Compatible:
1898 SecondConv = ICK_C_Only_Conversion;
1899 break;
1900 // For our purposes, discarding qualifiers is just as bad as using an
1901 // incompatible pointer. Note that an IncompatiblePointer conversion can drop
1902 // qualifiers, as well.
1903 case Sema::CompatiblePointerDiscardsQualifiers:
1904 case Sema::IncompatiblePointer:
1905 case Sema::IncompatiblePointerSign:
1906 SecondConv = ICK_Incompatible_Pointer_Conversion;
1907 break;
1908 default:
1909 return false;
1910 }
1911
1912 // First can only be an lvalue conversion, so we pretend that this was the
1913 // second conversion. First should already be valid from earlier in the
1914 // function.
1915 SCS.Second = SecondConv;
1916 SCS.setToType(1, ToType);
1917
1918 // Third is Identity, because Second should rank us worse than any other
1919 // conversion. This could also be ICK_Qualification, but it's simpler to just
1920 // lump everything in with the second conversion, and we don't gain anything
1921 // from making this ICK_Qualification.
1922 SCS.Third = ICK_Identity;
1923 SCS.setToType(2, ToType);
1924 return true;
1925}
1926
1927static bool
1928IsTransparentUnionStandardConversion(Sema &S, Expr* From,
1929 QualType &ToType,
1930 bool InOverloadResolution,
1931 StandardConversionSequence &SCS,
1932 bool CStyle) {
1933
1934 const RecordType *UT = ToType->getAsUnionType();
1935 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
1936 return false;
1937 // The field to initialize within the transparent union.
1938 RecordDecl *UD = UT->getDecl();
1939 // It's compatible if the expression matches any of the fields.
1940 for (const auto *it : UD->fields()) {
1941 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS,
1942 CStyle, /*ObjCWritebackConversion=*/false)) {
1943 ToType = it->getType();
1944 return true;
1945 }
1946 }
1947 return false;
1948}
1949
1950/// IsIntegralPromotion - Determines whether the conversion from the
1951/// expression From (whose potentially-adjusted type is FromType) to
1952/// ToType is an integral promotion (C++ 4.5). If so, returns true and
1953/// sets PromotedType to the promoted type.
1954bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) {
1955 const BuiltinType *To = ToType->getAs<BuiltinType>();
1956 // All integers are built-in.
1957 if (!To) {
1958 return false;
1959 }
1960
1961 // An rvalue of type char, signed char, unsigned char, short int, or
1962 // unsigned short int can be converted to an rvalue of type int if
1963 // int can represent all the values of the source type; otherwise,
1964 // the source rvalue can be converted to an rvalue of type unsigned
1965 // int (C++ 4.5p1).
1966 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() &&
1967 !FromType->isEnumeralType()) {
1968 if (// We can promote any signed, promotable integer type to an int
1969 (FromType->isSignedIntegerType() ||
1970 // We can promote any unsigned integer type whose size is
1971 // less than int to an int.
1972 Context.getTypeSize(FromType) < Context.getTypeSize(ToType))) {
1973 return To->getKind() == BuiltinType::Int;
1974 }
1975
1976 return To->getKind() == BuiltinType::UInt;
1977 }
1978
1979 // C++11 [conv.prom]p3:
1980 // A prvalue of an unscoped enumeration type whose underlying type is not
1981 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the
1982 // following types that can represent all the values of the enumeration
1983 // (i.e., the values in the range bmin to bmax as described in 7.2): int,
1984 // unsigned int, long int, unsigned long int, long long int, or unsigned
1985 // long long int. If none of the types in that list can represent all the
1986 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration
1987 // type can be converted to an rvalue a prvalue of the extended integer type
1988 // with lowest integer conversion rank (4.13) greater than the rank of long
1989 // long in which all the values of the enumeration can be represented. If
1990 // there are two such extended types, the signed one is chosen.
1991 // C++11 [conv.prom]p4:
1992 // A prvalue of an unscoped enumeration type whose underlying type is fixed
1993 // can be converted to a prvalue of its underlying type. Moreover, if
1994 // integral promotion can be applied to its underlying type, a prvalue of an
1995 // unscoped enumeration type whose underlying type is fixed can also be
1996 // converted to a prvalue of the promoted underlying type.
1997 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) {
1998 // C++0x 7.2p9: Note that this implicit enum to int conversion is not
1999 // provided for a scoped enumeration.
2000 if (FromEnumType->getDecl()->isScoped())
2001 return false;
2002
2003 // We can perform an integral promotion to the underlying type of the enum,
2004 // even if that's not the promoted type. Note that the check for promoting
2005 // the underlying type is based on the type alone, and does not consider
2006 // the bitfield-ness of the actual source expression.
2007 if (FromEnumType->getDecl()->isFixed()) {
2008 QualType Underlying = FromEnumType->getDecl()->getIntegerType();
2009 return Context.hasSameUnqualifiedType(Underlying, ToType) ||
2010 IsIntegralPromotion(nullptr, Underlying, ToType);
2011 }
2012
2013 // We have already pre-calculated the promotion type, so this is trivial.
2014 if (ToType->isIntegerType() &&
2015 isCompleteType(From->getBeginLoc(), FromType))
2016 return Context.hasSameUnqualifiedType(
2017 ToType, FromEnumType->getDecl()->getPromotionType());
2018
2019 // C++ [conv.prom]p5:
2020 // If the bit-field has an enumerated type, it is treated as any other
2021 // value of that type for promotion purposes.
2022 //
2023 // ... so do not fall through into the bit-field checks below in C++.
2024 if (getLangOpts().CPlusPlus)
2025 return false;
2026 }
2027
2028 // C++0x [conv.prom]p2:
2029 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted
2030 // to an rvalue a prvalue of the first of the following types that can
2031 // represent all the values of its underlying type: int, unsigned int,
2032 // long int, unsigned long int, long long int, or unsigned long long int.
2033 // If none of the types in that list can represent all the values of its
2034 // underlying type, an rvalue a prvalue of type char16_t, char32_t,
2035 // or wchar_t can be converted to an rvalue a prvalue of its underlying
2036 // type.
2037 if (FromType->isAnyCharacterType() && !FromType->isCharType() &&
2038 ToType->isIntegerType()) {
2039 // Determine whether the type we're converting from is signed or
2040 // unsigned.
2041 bool FromIsSigned = FromType->isSignedIntegerType();
2042 uint64_t FromSize = Context.getTypeSize(FromType);
2043
2044 // The types we'll try to promote to, in the appropriate
2045 // order. Try each of these types.
2046 QualType PromoteTypes[6] = {
2047 Context.IntTy, Context.UnsignedIntTy,
2048 Context.LongTy, Context.UnsignedLongTy ,
2049 Context.LongLongTy, Context.UnsignedLongLongTy
2050 };
2051 for (int Idx = 0; Idx < 6; ++Idx) {
2052 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]);
2053 if (FromSize < ToSize ||
2054 (FromSize == ToSize &&
2055 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) {
2056 // We found the type that we can promote to. If this is the
2057 // type we wanted, we have a promotion. Otherwise, no
2058 // promotion.
2059 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]);
2060 }
2061 }
2062 }
2063
2064 // An rvalue for an integral bit-field (9.6) can be converted to an
2065 // rvalue of type int if int can represent all the values of the
2066 // bit-field; otherwise, it can be converted to unsigned int if
2067 // unsigned int can represent all the values of the bit-field. If
2068 // the bit-field is larger yet, no integral promotion applies to
2069 // it. If the bit-field has an enumerated type, it is treated as any
2070 // other value of that type for promotion purposes (C++ 4.5p3).
2071 // FIXME: We should delay checking of bit-fields until we actually perform the
2072 // conversion.
2073 //
2074 // FIXME: In C, only bit-fields of types _Bool, int, or unsigned int may be
2075 // promoted, per C11 6.3.1.1/2. We promote all bit-fields (including enum
2076 // bit-fields and those whose underlying type is larger than int) for GCC
2077 // compatibility.
2078 if (From) {
2079 if (FieldDecl *MemberDecl = From->getSourceBitField()) {
2080 llvm::APSInt BitWidth;
2081 if (FromType->isIntegralType(Context) &&
2082 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) {
2083 llvm::APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned());
2084 ToSize = Context.getTypeSize(ToType);
2085
2086 // Are we promoting to an int from a bitfield that fits in an int?
2087 if (BitWidth < ToSize ||
2088 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) {
2089 return To->getKind() == BuiltinType::Int;
2090 }
2091
2092 // Are we promoting to an unsigned int from an unsigned bitfield
2093 // that fits into an unsigned int?
2094 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) {
2095 return To->getKind() == BuiltinType::UInt;
2096 }
2097
2098 return false;
2099 }
2100 }
2101 }
2102
2103 // An rvalue of type bool can be converted to an rvalue of type int,
2104 // with false becoming zero and true becoming one (C++ 4.5p4).
2105 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) {
2106 return true;
2107 }
2108
2109 return false;
2110}
2111
2112/// IsFloatingPointPromotion - Determines whether the conversion from
2113/// FromType to ToType is a floating point promotion (C++ 4.6). If so,
2114/// returns true and sets PromotedType to the promoted type.
2115bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) {
2116 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>())
2117 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) {
2118 /// An rvalue of type float can be converted to an rvalue of type
2119 /// double. (C++ 4.6p1).
2120 if (FromBuiltin->getKind() == BuiltinType::Float &&
2121 ToBuiltin->getKind() == BuiltinType::Double)
2122 return true;
2123
2124 // C99 6.3.1.5p1:
2125 // When a float is promoted to double or long double, or a
2126 // double is promoted to long double [...].
2127 if (!getLangOpts().CPlusPlus &&
2128 (FromBuiltin->getKind() == BuiltinType::Float ||
2129 FromBuiltin->getKind() == BuiltinType::Double) &&
2130 (ToBuiltin->getKind() == BuiltinType::LongDouble ||
2131 ToBuiltin->getKind() == BuiltinType::Float128))
2132 return true;
2133
2134 // Half can be promoted to float.
2135 if (!getLangOpts().NativeHalfType &&
2136 FromBuiltin->getKind() == BuiltinType::Half &&
2137 ToBuiltin->getKind() == BuiltinType::Float)
2138 return true;
2139 }
2140
2141 return false;
2142}
2143
2144/// Determine if a conversion is a complex promotion.
2145///
2146/// A complex promotion is defined as a complex -> complex conversion
2147/// where the conversion between the underlying real types is a
2148/// floating-point or integral promotion.
2149bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) {
2150 const ComplexType *FromComplex = FromType->getAs<ComplexType>();
2151 if (!FromComplex)
2152 return false;
2153
2154 const ComplexType *ToComplex = ToType->getAs<ComplexType>();
2155 if (!ToComplex)
2156 return false;
2157
2158 return IsFloatingPointPromotion(FromComplex->getElementType(),
2159 ToComplex->getElementType()) ||
2160 IsIntegralPromotion(nullptr, FromComplex->getElementType(),
2161 ToComplex->getElementType());
2162}
2163
2164/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from
2165/// the pointer type FromPtr to a pointer to type ToPointee, with the
2166/// same type qualifiers as FromPtr has on its pointee type. ToType,
2167/// if non-empty, will be a pointer to ToType that may or may not have
2168/// the right set of qualifiers on its pointee.
2169///
2170static QualType
2171BuildSimilarlyQualifiedPointerType(const Type *FromPtr,
2172 QualType ToPointee, QualType ToType,
2173 ASTContext &Context,
2174 bool StripObjCLifetime = false) {
2175 assert((FromPtr->getTypeClass() == Type::Pointer ||(((FromPtr->getTypeClass() == Type::Pointer || FromPtr->
getTypeClass() == Type::ObjCObjectPointer) && "Invalid similarly-qualified pointer type"
) ? static_cast<void> (0) : __assert_fail ("(FromPtr->getTypeClass() == Type::Pointer || FromPtr->getTypeClass() == Type::ObjCObjectPointer) && \"Invalid similarly-qualified pointer type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 2177, __PRETTY_FUNCTION__))
2176 FromPtr->getTypeClass() == Type::ObjCObjectPointer) &&(((FromPtr->getTypeClass() == Type::Pointer || FromPtr->
getTypeClass() == Type::ObjCObjectPointer) && "Invalid similarly-qualified pointer type"
) ? static_cast<void> (0) : __assert_fail ("(FromPtr->getTypeClass() == Type::Pointer || FromPtr->getTypeClass() == Type::ObjCObjectPointer) && \"Invalid similarly-qualified pointer type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 2177, __PRETTY_FUNCTION__))
2177 "Invalid similarly-qualified pointer type")(((FromPtr->getTypeClass() == Type::Pointer || FromPtr->
getTypeClass() == Type::ObjCObjectPointer) && "Invalid similarly-qualified pointer type"
) ? static_cast<void> (0) : __assert_fail ("(FromPtr->getTypeClass() == Type::Pointer || FromPtr->getTypeClass() == Type::ObjCObjectPointer) && \"Invalid similarly-qualified pointer type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 2177, __PRETTY_FUNCTION__))
;
2178
2179 /// Conversions to 'id' subsume cv-qualifier conversions.
2180 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType())
2181 return ToType.getUnqualifiedType();
2182
2183 QualType CanonFromPointee
2184 = Context.getCanonicalType(FromPtr->getPointeeType());
2185 QualType CanonToPointee = Context.getCanonicalType(ToPointee);
2186 Qualifiers Quals = CanonFromPointee.getQualifiers();
2187
2188 if (StripObjCLifetime)
2189 Quals.removeObjCLifetime();
2190
2191 // Exact qualifier match -> return the pointer type we're converting to.
2192 if (CanonToPointee.getLocalQualifiers() == Quals) {
2193 // ToType is exactly what we need. Return it.
2194 if (!ToType.isNull())
2195 return ToType.getUnqualifiedType();
2196
2197 // Build a pointer to ToPointee. It has the right qualifiers
2198 // already.
2199 if (isa<ObjCObjectPointerType>(ToType))
2200 return Context.getObjCObjectPointerType(ToPointee);
2201 return Context.getPointerType(ToPointee);
2202 }
2203
2204 // Just build a canonical type that has the right qualifiers.
2205 QualType QualifiedCanonToPointee
2206 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals);
2207
2208 if (isa<ObjCObjectPointerType>(ToType))
2209 return Context.getObjCObjectPointerType(QualifiedCanonToPointee);
2210 return Context.getPointerType(QualifiedCanonToPointee);
2211}
2212
2213static bool isNullPointerConstantForConversion(Expr *Expr,
2214 bool InOverloadResolution,
2215 ASTContext &Context) {
2216 // Handle value-dependent integral null pointer constants correctly.
2217 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903
2218 if (Expr->isValueDependent() && !Expr->isTypeDependent() &&
2219 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType())
2220 return !InOverloadResolution;
2221
2222 return Expr->isNullPointerConstant(Context,
2223 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull
2224 : Expr::NPC_ValueDependentIsNull);
2225}
2226
2227/// IsPointerConversion - Determines whether the conversion of the
2228/// expression From, which has the (possibly adjusted) type FromType,
2229/// can be converted to the type ToType via a pointer conversion (C++
2230/// 4.10). If so, returns true and places the converted type (that
2231/// might differ from ToType in its cv-qualifiers at some level) into
2232/// ConvertedType.
2233///
2234/// This routine also supports conversions to and from block pointers
2235/// and conversions with Objective-C's 'id', 'id<protocols...>', and
2236/// pointers to interfaces. FIXME: Once we've determined the
2237/// appropriate overloading rules for Objective-C, we may want to
2238/// split the Objective-C checks into a different routine; however,
2239/// GCC seems to consider all of these conversions to be pointer
2240/// conversions, so for now they live here. IncompatibleObjC will be
2241/// set if the conversion is an allowed Objective-C conversion that
2242/// should result in a warning.
2243bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
2244 bool InOverloadResolution,
2245 QualType& ConvertedType,
2246 bool &IncompatibleObjC) {
2247 IncompatibleObjC = false;
2248 if (isObjCPointerConversion(FromType, ToType, ConvertedType,
2249 IncompatibleObjC))
2250 return true;
2251
2252 // Conversion from a null pointer constant to any Objective-C pointer type.
2253 if (ToType->isObjCObjectPointerType() &&
2254 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2255 ConvertedType = ToType;
2256 return true;
2257 }
2258
2259 // Blocks: Block pointers can be converted to void*.
2260 if (FromType->isBlockPointerType() && ToType->isPointerType() &&
2261 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) {
2262 ConvertedType = ToType;
2263 return true;
2264 }
2265 // Blocks: A null pointer constant can be converted to a block
2266 // pointer type.
2267 if (ToType->isBlockPointerType() &&
2268 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2269 ConvertedType = ToType;
2270 return true;
2271 }
2272
2273 // If the left-hand-side is nullptr_t, the right side can be a null
2274 // pointer constant.
2275 if (ToType->isNullPtrType() &&
2276 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2277 ConvertedType = ToType;
2278 return true;
2279 }
2280
2281 const PointerType* ToTypePtr = ToType->getAs<PointerType>();
2282 if (!ToTypePtr)
2283 return false;
2284
2285 // A null pointer constant can be converted to a pointer type (C++ 4.10p1).
2286 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) {
2287 ConvertedType = ToType;
2288 return true;
2289 }
2290
2291 // Beyond this point, both types need to be pointers
2292 // , including objective-c pointers.
2293 QualType ToPointeeType = ToTypePtr->getPointeeType();
2294 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() &&
2295 !getLangOpts().ObjCAutoRefCount) {
2296 ConvertedType = BuildSimilarlyQualifiedPointerType(
2297 FromType->getAs<ObjCObjectPointerType>(),
2298 ToPointeeType,
2299 ToType, Context);
2300 return true;
2301 }
2302 const PointerType *FromTypePtr = FromType->getAs<PointerType>();
2303 if (!FromTypePtr)
2304 return false;
2305
2306 QualType FromPointeeType = FromTypePtr->getPointeeType();
2307
2308 // If the unqualified pointee types are the same, this can't be a
2309 // pointer conversion, so don't do all of the work below.
2310 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType))
2311 return false;
2312
2313 // An rvalue of type "pointer to cv T," where T is an object type,
2314 // can be converted to an rvalue of type "pointer to cv void" (C++
2315 // 4.10p2).
2316 if (FromPointeeType->isIncompleteOrObjectType() &&
2317 ToPointeeType->isVoidType()) {
2318 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2319 ToPointeeType,
2320 ToType, Context,
2321 /*StripObjCLifetime=*/true);
2322 return true;
2323 }
2324
2325 // MSVC allows implicit function to void* type conversion.
2326 if (getLangOpts().MSVCCompat && FromPointeeType->isFunctionType() &&
2327 ToPointeeType->isVoidType()) {
2328 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2329 ToPointeeType,
2330 ToType, Context);
2331 return true;
2332 }
2333
2334 // When we're overloading in C, we allow a special kind of pointer
2335 // conversion for compatible-but-not-identical pointee types.
2336 if (!getLangOpts().CPlusPlus &&
2337 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) {
2338 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2339 ToPointeeType,
2340 ToType, Context);
2341 return true;
2342 }
2343
2344 // C++ [conv.ptr]p3:
2345 //
2346 // An rvalue of type "pointer to cv D," where D is a class type,
2347 // can be converted to an rvalue of type "pointer to cv B," where
2348 // B is a base class (clause 10) of D. If B is an inaccessible
2349 // (clause 11) or ambiguous (10.2) base class of D, a program that
2350 // necessitates this conversion is ill-formed. The result of the
2351 // conversion is a pointer to the base class sub-object of the
2352 // derived class object. The null pointer value is converted to
2353 // the null pointer value of the destination type.
2354 //
2355 // Note that we do not check for ambiguity or inaccessibility
2356 // here. That is handled by CheckPointerConversion.
2357 if (getLangOpts().CPlusPlus && FromPointeeType->isRecordType() &&
2358 ToPointeeType->isRecordType() &&
2359 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) &&
2360 IsDerivedFrom(From->getBeginLoc(), FromPointeeType, ToPointeeType)) {
2361 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2362 ToPointeeType,
2363 ToType, Context);
2364 return true;
2365 }
2366
2367 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() &&
2368 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) {
2369 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr,
2370 ToPointeeType,
2371 ToType, Context);
2372 return true;
2373 }
2374
2375 return false;
2376}
2377
2378/// Adopt the given qualifiers for the given type.
2379static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){
2380 Qualifiers TQs = T.getQualifiers();
2381
2382 // Check whether qualifiers already match.
2383 if (TQs == Qs)
2384 return T;
2385
2386 if (Qs.compatiblyIncludes(TQs))
2387 return Context.getQualifiedType(T, Qs);
2388
2389 return Context.getQualifiedType(T.getUnqualifiedType(), Qs);
2390}
2391
2392/// isObjCPointerConversion - Determines whether this is an
2393/// Objective-C pointer conversion. Subroutine of IsPointerConversion,
2394/// with the same arguments and return values.
2395bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType,
2396 QualType& ConvertedType,
2397 bool &IncompatibleObjC) {
2398 if (!getLangOpts().ObjC1)
2399 return false;
2400
2401 // The set of qualifiers on the type we're converting from.
2402 Qualifiers FromQualifiers = FromType.getQualifiers();
2403
2404 // First, we handle all conversions on ObjC object pointer types.
2405 const ObjCObjectPointerType* ToObjCPtr =
2406 ToType->getAs<ObjCObjectPointerType>();
2407 const ObjCObjectPointerType *FromObjCPtr =
2408 FromType->getAs<ObjCObjectPointerType>();
2409
2410 if (ToObjCPtr && FromObjCPtr) {
2411 // If the pointee types are the same (ignoring qualifications),
2412 // then this is not a pointer conversion.
2413 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(),
2414 FromObjCPtr->getPointeeType()))
2415 return false;
2416
2417 // Conversion between Objective-C pointers.
2418 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) {
2419 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType();
2420 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType();
2421 if (getLangOpts().CPlusPlus && LHS && RHS &&
2422 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs(
2423 FromObjCPtr->getPointeeType()))
2424 return false;
2425 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr,
2426 ToObjCPtr->getPointeeType(),
2427 ToType, Context);
2428 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2429 return true;
2430 }
2431
2432 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) {
2433 // Okay: this is some kind of implicit downcast of Objective-C
2434 // interfaces, which is permitted. However, we're going to
2435 // complain about it.
2436 IncompatibleObjC = true;
2437 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr,
2438 ToObjCPtr->getPointeeType(),
2439 ToType, Context);
2440 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2441 return true;
2442 }
2443 }
2444 // Beyond this point, both types need to be C pointers or block pointers.
2445 QualType ToPointeeType;
2446 if (const PointerType *ToCPtr = ToType->getAs<PointerType>())
2447 ToPointeeType = ToCPtr->getPointeeType();
2448 else if (const BlockPointerType *ToBlockPtr =
2449 ToType->getAs<BlockPointerType>()) {
2450 // Objective C++: We're able to convert from a pointer to any object
2451 // to a block pointer type.
2452 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) {
2453 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2454 return true;
2455 }
2456 ToPointeeType = ToBlockPtr->getPointeeType();
2457 }
2458 else if (FromType->getAs<BlockPointerType>() &&
2459 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) {
2460 // Objective C++: We're able to convert from a block pointer type to a
2461 // pointer to any object.
2462 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2463 return true;
2464 }
2465 else
2466 return false;
2467
2468 QualType FromPointeeType;
2469 if (const PointerType *FromCPtr = FromType->getAs<PointerType>())
2470 FromPointeeType = FromCPtr->getPointeeType();
2471 else if (const BlockPointerType *FromBlockPtr =
2472 FromType->getAs<BlockPointerType>())
2473 FromPointeeType = FromBlockPtr->getPointeeType();
2474 else
2475 return false;
2476
2477 // If we have pointers to pointers, recursively check whether this
2478 // is an Objective-C conversion.
2479 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() &&
2480 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType,
2481 IncompatibleObjC)) {
2482 // We always complain about this conversion.
2483 IncompatibleObjC = true;
2484 ConvertedType = Context.getPointerType(ConvertedType);
2485 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2486 return true;
2487 }
2488 // Allow conversion of pointee being objective-c pointer to another one;
2489 // as in I* to id.
2490 if (FromPointeeType->getAs<ObjCObjectPointerType>() &&
2491 ToPointeeType->getAs<ObjCObjectPointerType>() &&
2492 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType,
2493 IncompatibleObjC)) {
2494
2495 ConvertedType = Context.getPointerType(ConvertedType);
2496 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers);
2497 return true;
2498 }
2499
2500 // If we have pointers to functions or blocks, check whether the only
2501 // differences in the argument and result types are in Objective-C
2502 // pointer conversions. If so, we permit the conversion (but
2503 // complain about it).
2504 const FunctionProtoType *FromFunctionType
2505 = FromPointeeType->getAs<FunctionProtoType>();
2506 const FunctionProtoType *ToFunctionType
2507 = ToPointeeType->getAs<FunctionProtoType>();
2508 if (FromFunctionType && ToFunctionType) {
2509 // If the function types are exactly the same, this isn't an
2510 // Objective-C pointer conversion.
2511 if (Context.getCanonicalType(FromPointeeType)
2512 == Context.getCanonicalType(ToPointeeType))
2513 return false;
2514
2515 // Perform the quick checks that will tell us whether these
2516 // function types are obviously different.
2517 if (FromFunctionType->getNumParams() != ToFunctionType->getNumParams() ||
2518 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() ||
2519 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals())
2520 return false;
2521
2522 bool HasObjCConversion = false;
2523 if (Context.getCanonicalType(FromFunctionType->getReturnType()) ==
2524 Context.getCanonicalType(ToFunctionType->getReturnType())) {
2525 // Okay, the types match exactly. Nothing to do.
2526 } else if (isObjCPointerConversion(FromFunctionType->getReturnType(),
2527 ToFunctionType->getReturnType(),
2528 ConvertedType, IncompatibleObjC)) {
2529 // Okay, we have an Objective-C pointer conversion.
2530 HasObjCConversion = true;
2531 } else {
2532 // Function types are too different. Abort.
2533 return false;
2534 }
2535
2536 // Check argument types.
2537 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumParams();
2538 ArgIdx != NumArgs; ++ArgIdx) {
2539 QualType FromArgType = FromFunctionType->getParamType(ArgIdx);
2540 QualType ToArgType = ToFunctionType->getParamType(ArgIdx);
2541 if (Context.getCanonicalType(FromArgType)
2542 == Context.getCanonicalType(ToArgType)) {
2543 // Okay, the types match exactly. Nothing to do.
2544 } else if (isObjCPointerConversion(FromArgType, ToArgType,
2545 ConvertedType, IncompatibleObjC)) {
2546 // Okay, we have an Objective-C pointer conversion.
2547 HasObjCConversion = true;
2548 } else {
2549 // Argument types are too different. Abort.
2550 return false;
2551 }
2552 }
2553
2554 if (HasObjCConversion) {
2555 // We had an Objective-C conversion. Allow this pointer
2556 // conversion, but complain about it.
2557 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers);
2558 IncompatibleObjC = true;
2559 return true;
2560 }
2561 }
2562
2563 return false;
2564}
2565
2566/// Determine whether this is an Objective-C writeback conversion,
2567/// used for parameter passing when performing automatic reference counting.
2568///
2569/// \param FromType The type we're converting form.
2570///
2571/// \param ToType The type we're converting to.
2572///
2573/// \param ConvertedType The type that will be produced after applying
2574/// this conversion.
2575bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType,
2576 QualType &ConvertedType) {
2577 if (!getLangOpts().ObjCAutoRefCount ||
2578 Context.hasSameUnqualifiedType(FromType, ToType))
2579 return false;
2580
2581 // Parameter must be a pointer to __autoreleasing (with no other qualifiers).
2582 QualType ToPointee;
2583 if (const PointerType *ToPointer = ToType->getAs<PointerType>())
2584 ToPointee = ToPointer->getPointeeType();
2585 else
2586 return false;
2587
2588 Qualifiers ToQuals = ToPointee.getQualifiers();
2589 if (!ToPointee->isObjCLifetimeType() ||
2590 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing ||
2591 !ToQuals.withoutObjCLifetime().empty())
2592 return false;
2593
2594 // Argument must be a pointer to __strong to __weak.
2595 QualType FromPointee;
2596 if (const PointerType *FromPointer = FromType->getAs<PointerType>())
2597 FromPointee = FromPointer->getPointeeType();
2598 else
2599 return false;
2600
2601 Qualifiers FromQuals = FromPointee.getQualifiers();
2602 if (!FromPointee->isObjCLifetimeType() ||
2603 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong &&
2604 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak))
2605 return false;
2606
2607 // Make sure that we have compatible qualifiers.
2608 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing);
2609 if (!ToQuals.compatiblyIncludes(FromQuals))
2610 return false;
2611
2612 // Remove qualifiers from the pointee type we're converting from; they
2613 // aren't used in the compatibility check belong, and we'll be adding back
2614 // qualifiers (with __autoreleasing) if the compatibility check succeeds.
2615 FromPointee = FromPointee.getUnqualifiedType();
2616
2617 // The unqualified form of the pointee types must be compatible.
2618 ToPointee = ToPointee.getUnqualifiedType();
2619 bool IncompatibleObjC;
2620 if (Context.typesAreCompatible(FromPointee, ToPointee))
2621 FromPointee = ToPointee;
2622 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee,
2623 IncompatibleObjC))
2624 return false;
2625
2626 /// Construct the type we're converting to, which is a pointer to
2627 /// __autoreleasing pointee.
2628 FromPointee = Context.getQualifiedType(FromPointee, FromQuals);
2629 ConvertedType = Context.getPointerType(FromPointee);
2630 return true;
2631}
2632
2633bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType,
2634 QualType& ConvertedType) {
2635 QualType ToPointeeType;
2636 if (const BlockPointerType *ToBlockPtr =
2637 ToType->getAs<BlockPointerType>())
2638 ToPointeeType = ToBlockPtr->getPointeeType();
2639 else
2640 return false;
2641
2642 QualType FromPointeeType;
2643 if (const BlockPointerType *FromBlockPtr =
2644 FromType->getAs<BlockPointerType>())
2645 FromPointeeType = FromBlockPtr->getPointeeType();
2646 else
2647 return false;
2648 // We have pointer to blocks, check whether the only
2649 // differences in the argument and result types are in Objective-C
2650 // pointer conversions. If so, we permit the conversion.
2651
2652 const FunctionProtoType *FromFunctionType
2653 = FromPointeeType->getAs<FunctionProtoType>();
2654 const FunctionProtoType *ToFunctionType
2655 = ToPointeeType->getAs<FunctionProtoType>();
2656
2657 if (!FromFunctionType || !ToFunctionType)
2658 return false;
2659
2660 if (Context.hasSameType(FromPointeeType, ToPointeeType))
2661 return true;
2662
2663 // Perform the quick checks that will tell us whether these
2664 // function types are obviously different.
2665 if (FromFunctionType->getNumParams() != ToFunctionType->getNumParams() ||
2666 FromFunctionType->isVariadic() != ToFunctionType->isVariadic())
2667 return false;
2668
2669 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo();
2670 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo();
2671 if (FromEInfo != ToEInfo)
2672 return false;
2673
2674 bool IncompatibleObjC = false;
2675 if (Context.hasSameType(FromFunctionType->getReturnType(),
2676 ToFunctionType->getReturnType())) {
2677 // Okay, the types match exactly. Nothing to do.
2678 } else {
2679 QualType RHS = FromFunctionType->getReturnType();
2680 QualType LHS = ToFunctionType->getReturnType();
2681 if ((!getLangOpts().CPlusPlus || !RHS->isRecordType()) &&
2682 !RHS.hasQualifiers() && LHS.hasQualifiers())
2683 LHS = LHS.getUnqualifiedType();
2684
2685 if (Context.hasSameType(RHS,LHS)) {
2686 // OK exact match.
2687 } else if (isObjCPointerConversion(RHS, LHS,
2688 ConvertedType, IncompatibleObjC)) {
2689 if (IncompatibleObjC)
2690 return false;
2691 // Okay, we have an Objective-C pointer conversion.
2692 }
2693 else
2694 return false;
2695 }
2696
2697 // Check argument types.
2698 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumParams();
2699 ArgIdx != NumArgs; ++ArgIdx) {
2700 IncompatibleObjC = false;
2701 QualType FromArgType = FromFunctionType->getParamType(ArgIdx);
2702 QualType ToArgType = ToFunctionType->getParamType(ArgIdx);
2703 if (Context.hasSameType(FromArgType, ToArgType)) {
2704 // Okay, the types match exactly. Nothing to do.
2705 } else if (isObjCPointerConversion(ToArgType, FromArgType,
2706 ConvertedType, IncompatibleObjC)) {
2707 if (IncompatibleObjC)
2708 return false;
2709 // Okay, we have an Objective-C pointer conversion.
2710 } else
2711 // Argument types are too different. Abort.
2712 return false;
2713 }
2714
2715 SmallVector<FunctionProtoType::ExtParameterInfo, 4> NewParamInfos;
2716 bool CanUseToFPT, CanUseFromFPT;
2717 if (!Context.mergeExtParameterInfo(ToFunctionType, FromFunctionType,
2718 CanUseToFPT, CanUseFromFPT,
2719 NewParamInfos))
2720 return false;
2721
2722 ConvertedType = ToType;
2723 return true;
2724}
2725
2726enum {
2727 ft_default,
2728 ft_different_class,
2729 ft_parameter_arity,
2730 ft_parameter_mismatch,
2731 ft_return_type,
2732 ft_qualifer_mismatch,
2733 ft_noexcept
2734};
2735
2736/// Attempts to get the FunctionProtoType from a Type. Handles
2737/// MemberFunctionPointers properly.
2738static const FunctionProtoType *tryGetFunctionProtoType(QualType FromType) {
2739 if (auto *FPT = FromType->getAs<FunctionProtoType>())
2740 return FPT;
2741
2742 if (auto *MPT = FromType->getAs<MemberPointerType>())
2743 return MPT->getPointeeType()->getAs<FunctionProtoType>();
2744
2745 return nullptr;
2746}
2747
2748/// HandleFunctionTypeMismatch - Gives diagnostic information for differeing
2749/// function types. Catches different number of parameter, mismatch in
2750/// parameter types, and different return types.
2751void Sema::HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
2752 QualType FromType, QualType ToType) {
2753 // If either type is not valid, include no extra info.
2754 if (FromType.isNull() || ToType.isNull()) {
2755 PDiag << ft_default;
2756 return;
2757 }
2758
2759 // Get the function type from the pointers.
2760 if (FromType->isMemberPointerType() && ToType->isMemberPointerType()) {
2761 const MemberPointerType *FromMember = FromType->getAs<MemberPointerType>(),
2762 *ToMember = ToType->getAs<MemberPointerType>();
2763 if (!Context.hasSameType(FromMember->getClass(), ToMember->getClass())) {
2764 PDiag << ft_different_class << QualType(ToMember->getClass(), 0)
2765 << QualType(FromMember->getClass(), 0);
2766 return;
2767 }
2768 FromType = FromMember->getPointeeType();
2769 ToType = ToMember->getPointeeType();
2770 }
2771
2772 if (FromType->isPointerType())
2773 FromType = FromType->getPointeeType();
2774 if (ToType->isPointerType())
2775 ToType = ToType->getPointeeType();
2776
2777 // Remove references.
2778 FromType = FromType.getNonReferenceType();
2779 ToType = ToType.getNonReferenceType();
2780
2781 // Don't print extra info for non-specialized template functions.
2782 if (FromType->isInstantiationDependentType() &&
2783 !FromType->getAs<TemplateSpecializationType>()) {
2784 PDiag << ft_default;
2785 return;
2786 }
2787
2788 // No extra info for same types.
2789 if (Context.hasSameType(FromType, ToType)) {
2790 PDiag << ft_default;
2791 return;
2792 }
2793
2794 const FunctionProtoType *FromFunction = tryGetFunctionProtoType(FromType),
2795 *ToFunction = tryGetFunctionProtoType(ToType);
2796
2797 // Both types need to be function types.
2798 if (!FromFunction || !ToFunction) {
2799 PDiag << ft_default;
2800 return;
2801 }
2802
2803 if (FromFunction->getNumParams() != ToFunction->getNumParams()) {
2804 PDiag << ft_parameter_arity << ToFunction->getNumParams()
2805 << FromFunction->getNumParams();
2806 return;
2807 }
2808
2809 // Handle different parameter types.
2810 unsigned ArgPos;
2811 if (!FunctionParamTypesAreEqual(FromFunction, ToFunction, &ArgPos)) {
2812 PDiag << ft_parameter_mismatch << ArgPos + 1
2813 << ToFunction->getParamType(ArgPos)
2814 << FromFunction->getParamType(ArgPos);
2815 return;
2816 }
2817
2818 // Handle different return type.
2819 if (!Context.hasSameType(FromFunction->getReturnType(),
2820 ToFunction->getReturnType())) {
2821 PDiag << ft_return_type << ToFunction->getReturnType()
2822 << FromFunction->getReturnType();
2823 return;
2824 }
2825
2826 unsigned FromQuals = FromFunction->getTypeQuals(),
2827 ToQuals = ToFunction->getTypeQuals();
2828 if (FromQuals != ToQuals) {
2829 PDiag << ft_qualifer_mismatch << ToQuals << FromQuals;
2830 return;
2831 }
2832
2833 // Handle exception specification differences on canonical type (in C++17
2834 // onwards).
2835 if (cast<FunctionProtoType>(FromFunction->getCanonicalTypeUnqualified())
2836 ->isNothrow() !=
2837 cast<FunctionProtoType>(ToFunction->getCanonicalTypeUnqualified())
2838 ->isNothrow()) {
2839 PDiag << ft_noexcept;
2840 return;
2841 }
2842
2843 // Unable to find a difference, so add no extra info.
2844 PDiag << ft_default;
2845}
2846
2847/// FunctionParamTypesAreEqual - This routine checks two function proto types
2848/// for equality of their argument types. Caller has already checked that
2849/// they have same number of arguments. If the parameters are different,
2850/// ArgPos will have the parameter index of the first different parameter.
2851bool Sema::FunctionParamTypesAreEqual(const FunctionProtoType *OldType,
2852 const FunctionProtoType *NewType,
2853 unsigned *ArgPos) {
2854 for (FunctionProtoType::param_type_iterator O = OldType->param_type_begin(),
2855 N = NewType->param_type_begin(),
2856 E = OldType->param_type_end();
2857 O && (O != E); ++O, ++N) {
2858 if (!Context.hasSameType(O->getUnqualifiedType(),
2859 N->getUnqualifiedType())) {
2860 if (ArgPos)
2861 *ArgPos = O - OldType->param_type_begin();
2862 return false;
2863 }
2864 }
2865 return true;
2866}
2867
2868/// CheckPointerConversion - Check the pointer conversion from the
2869/// expression From to the type ToType. This routine checks for
2870/// ambiguous or inaccessible derived-to-base pointer
2871/// conversions for which IsPointerConversion has already returned
2872/// true. It returns true and produces a diagnostic if there was an
2873/// error, or returns false otherwise.
2874bool Sema::CheckPointerConversion(Expr *From, QualType ToType,
2875 CastKind &Kind,
2876 CXXCastPath& BasePath,
2877 bool IgnoreBaseAccess,
2878 bool Diagnose) {
2879 QualType FromType = From->getType();
2880 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess;
2881
2882 Kind = CK_BitCast;
2883
2884 if (Diagnose && !IsCStyleOrFunctionalCast && !FromType->isAnyPointerType() &&
2885 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) ==
2886 Expr::NPCK_ZeroExpression) {
2887 if (Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy))
2888 DiagRuntimeBehavior(From->getExprLoc(), From,
2889 PDiag(diag::warn_impcast_bool_to_null_pointer)
2890 << ToType << From->getSourceRange());
2891 else if (!isUnevaluatedContext())
2892 Diag(From->getExprLoc(), diag::warn_non_literal_null_pointer)
2893 << ToType << From->getSourceRange();
2894 }
2895 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) {
2896 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) {
2897 QualType FromPointeeType = FromPtrType->getPointeeType(),
2898 ToPointeeType = ToPtrType->getPointeeType();
2899
2900 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() &&
2901 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) {
2902 // We must have a derived-to-base conversion. Check an
2903 // ambiguous or inaccessible conversion.
2904 unsigned InaccessibleID = 0;
2905 unsigned AmbigiousID = 0;
2906 if (Diagnose) {
2907 InaccessibleID = diag::err_upcast_to_inaccessible_base;
2908 AmbigiousID = diag::err_ambiguous_derived_to_base_conv;
2909 }
2910 if (CheckDerivedToBaseConversion(
2911 FromPointeeType, ToPointeeType, InaccessibleID, AmbigiousID,
2912 From->getExprLoc(), From->getSourceRange(), DeclarationName(),
2913 &BasePath, IgnoreBaseAccess))
2914 return true;
2915
2916 // The conversion was successful.
2917 Kind = CK_DerivedToBase;
2918 }
2919
2920 if (Diagnose && !IsCStyleOrFunctionalCast &&
2921 FromPointeeType->isFunctionType() && ToPointeeType->isVoidType()) {
2922 assert(getLangOpts().MSVCCompat &&((getLangOpts().MSVCCompat && "this should only be possible with MSVCCompat!"
) ? static_cast<void> (0) : __assert_fail ("getLangOpts().MSVCCompat && \"this should only be possible with MSVCCompat!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 2923, __PRETTY_FUNCTION__))
2923 "this should only be possible with MSVCCompat!")((getLangOpts().MSVCCompat && "this should only be possible with MSVCCompat!"
) ? static_cast<void> (0) : __assert_fail ("getLangOpts().MSVCCompat && \"this should only be possible with MSVCCompat!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 2923, __PRETTY_FUNCTION__))
;
2924 Diag(From->getExprLoc(), diag::ext_ms_impcast_fn_obj)
2925 << From->getSourceRange();
2926 }
2927 }
2928 } else if (const ObjCObjectPointerType *ToPtrType =
2929 ToType->getAs<ObjCObjectPointerType>()) {
2930 if (const ObjCObjectPointerType *FromPtrType =
2931 FromType->getAs<ObjCObjectPointerType>()) {
2932 // Objective-C++ conversions are always okay.
2933 // FIXME: We should have a different class of conversions for the
2934 // Objective-C++ implicit conversions.
2935 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType())
2936 return false;
2937 } else if (FromType->isBlockPointerType()) {
2938 Kind = CK_BlockPointerToObjCPointerCast;
2939 } else {
2940 Kind = CK_CPointerToObjCPointerCast;
2941 }
2942 } else if (ToType->isBlockPointerType()) {
2943 if (!FromType->isBlockPointerType())
2944 Kind = CK_AnyPointerToBlockPointerCast;
2945 }
2946
2947 // We shouldn't fall into this case unless it's valid for other
2948 // reasons.
2949 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull))
2950 Kind = CK_NullToPointer;
2951
2952 return false;
2953}
2954
2955/// IsMemberPointerConversion - Determines whether the conversion of the
2956/// expression From, which has the (possibly adjusted) type FromType, can be
2957/// converted to the type ToType via a member pointer conversion (C++ 4.11).
2958/// If so, returns true and places the converted type (that might differ from
2959/// ToType in its cv-qualifiers at some level) into ConvertedType.
2960bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType,
2961 QualType ToType,
2962 bool InOverloadResolution,
2963 QualType &ConvertedType) {
2964 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>();
2965 if (!ToTypePtr)
2966 return false;
2967
2968 // A null pointer constant can be converted to a member pointer (C++ 4.11p1)
2969 if (From->isNullPointerConstant(Context,
2970 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull
2971 : Expr::NPC_ValueDependentIsNull)) {
2972 ConvertedType = ToType;
2973 return true;
2974 }
2975
2976 // Otherwise, both types have to be member pointers.
2977 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>();
2978 if (!FromTypePtr)
2979 return false;
2980
2981 // A pointer to member of B can be converted to a pointer to member of D,
2982 // where D is derived from B (C++ 4.11p2).
2983 QualType FromClass(FromTypePtr->getClass(), 0);
2984 QualType ToClass(ToTypePtr->getClass(), 0);
2985
2986 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) &&
2987 IsDerivedFrom(From->getBeginLoc(), ToClass, FromClass)) {
2988 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(),
2989 ToClass.getTypePtr());
2990 return true;
2991 }
2992
2993 return false;
2994}
2995
2996/// CheckMemberPointerConversion - Check the member pointer conversion from the
2997/// expression From to the type ToType. This routine checks for ambiguous or
2998/// virtual or inaccessible base-to-derived member pointer conversions
2999/// for which IsMemberPointerConversion has already returned true. It returns
3000/// true and produces a diagnostic if there was an error, or returns false
3001/// otherwise.
3002bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType,
3003 CastKind &Kind,
3004 CXXCastPath &BasePath,
3005 bool IgnoreBaseAccess) {
3006 QualType FromType = From->getType();
3007 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>();
3008 if (!FromPtrType) {
3009 // This must be a null pointer to member pointer conversion
3010 assert(From->isNullPointerConstant(Context,((From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull
) && "Expr must be null pointer constant!") ? static_cast
<void> (0) : __assert_fail ("From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull) && \"Expr must be null pointer constant!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3012, __PRETTY_FUNCTION__))
3011 Expr::NPC_ValueDependentIsNull) &&((From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull
) && "Expr must be null pointer constant!") ? static_cast
<void> (0) : __assert_fail ("From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull) && \"Expr must be null pointer constant!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3012, __PRETTY_FUNCTION__))
3012 "Expr must be null pointer constant!")((From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull
) && "Expr must be null pointer constant!") ? static_cast
<void> (0) : __assert_fail ("From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull) && \"Expr must be null pointer constant!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3012, __PRETTY_FUNCTION__))
;
3013 Kind = CK_NullToMemberPointer;
3014 return false;
3015 }
3016
3017 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>();
3018 assert(ToPtrType && "No member pointer cast has a target type "((ToPtrType && "No member pointer cast has a target type "
"that is not a member pointer.") ? static_cast<void> (
0) : __assert_fail ("ToPtrType && \"No member pointer cast has a target type \" \"that is not a member pointer.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3019, __PRETTY_FUNCTION__))
3019 "that is not a member pointer.")((ToPtrType && "No member pointer cast has a target type "
"that is not a member pointer.") ? static_cast<void> (
0) : __assert_fail ("ToPtrType && \"No member pointer cast has a target type \" \"that is not a member pointer.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3019, __PRETTY_FUNCTION__))
;
3020
3021 QualType FromClass = QualType(FromPtrType->getClass(), 0);
3022 QualType ToClass = QualType(ToPtrType->getClass(), 0);
3023
3024 // FIXME: What about dependent types?
3025 assert(FromClass->isRecordType() && "Pointer into non-class.")((FromClass->isRecordType() && "Pointer into non-class."
) ? static_cast<void> (0) : __assert_fail ("FromClass->isRecordType() && \"Pointer into non-class.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3025, __PRETTY_FUNCTION__))
;
3026 assert(ToClass->isRecordType() && "Pointer into non-class.")((ToClass->isRecordType() && "Pointer into non-class."
) ? static_cast<void> (0) : __assert_fail ("ToClass->isRecordType() && \"Pointer into non-class.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3026, __PRETTY_FUNCTION__))
;
3027
3028 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3029 /*DetectVirtual=*/true);
3030 bool DerivationOkay =
3031 IsDerivedFrom(From->getBeginLoc(), ToClass, FromClass, Paths);
3032 assert(DerivationOkay &&((DerivationOkay && "Should not have been called if derivation isn't OK."
) ? static_cast<void> (0) : __assert_fail ("DerivationOkay && \"Should not have been called if derivation isn't OK.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3033, __PRETTY_FUNCTION__))
3033 "Should not have been called if derivation isn't OK.")((DerivationOkay && "Should not have been called if derivation isn't OK."
) ? static_cast<void> (0) : __assert_fail ("DerivationOkay && \"Should not have been called if derivation isn't OK.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3033, __PRETTY_FUNCTION__))
;
3034 (void)DerivationOkay;
3035
3036 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass).
3037 getUnqualifiedType())) {
3038 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
3039 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv)
3040 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange();
3041 return true;
3042 }
3043
3044 if (const RecordType *VBase = Paths.getDetectedVirtual()) {
3045 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual)
3046 << FromClass << ToClass << QualType(VBase, 0)
3047 << From->getSourceRange();
3048 return true;
3049 }
3050
3051 if (!IgnoreBaseAccess)
3052 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass,
3053 Paths.front(),
3054 diag::err_downcast_from_inaccessible_base);
3055
3056 // Must be a base to derived member conversion.
3057 BuildBasePathArray(Paths, BasePath);
3058 Kind = CK_BaseToDerivedMemberPointer;
3059 return false;
3060}
3061
3062/// Determine whether the lifetime conversion between the two given
3063/// qualifiers sets is nontrivial.
3064static bool isNonTrivialObjCLifetimeConversion(Qualifiers FromQuals,
3065 Qualifiers ToQuals) {
3066 // Converting anything to const __unsafe_unretained is trivial.
3067 if (ToQuals.hasConst() &&
3068 ToQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone)
3069 return false;
3070
3071 return true;
3072}
3073
3074/// IsQualificationConversion - Determines whether the conversion from
3075/// an rvalue of type FromType to ToType is a qualification conversion
3076/// (C++ 4.4).
3077///
3078/// \param ObjCLifetimeConversion Output parameter that will be set to indicate
3079/// when the qualification conversion involves a change in the Objective-C
3080/// object lifetime.
3081bool
3082Sema::IsQualificationConversion(QualType FromType, QualType ToType,
3083 bool CStyle, bool &ObjCLifetimeConversion) {
3084 FromType = Context.getCanonicalType(FromType);
3085 ToType = Context.getCanonicalType(ToType);
3086 ObjCLifetimeConversion = false;
3087
3088 // If FromType and ToType are the same type, this is not a
3089 // qualification conversion.
3090 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType())
3091 return false;
3092
3093 // (C++ 4.4p4):
3094 // A conversion can add cv-qualifiers at levels other than the first
3095 // in multi-level pointers, subject to the following rules: [...]
3096 bool PreviousToQualsIncludeConst = true;
3097 bool UnwrappedAnyPointer = false;
3098 while (Context.UnwrapSimilarTypes(FromType, ToType)) {
3099 // Within each iteration of the loop, we check the qualifiers to
3100 // determine if this still looks like a qualification
3101 // conversion. Then, if all is well, we unwrap one more level of
3102 // pointers or pointers-to-members and do it all again
3103 // until there are no more pointers or pointers-to-members left to
3104 // unwrap.
3105 UnwrappedAnyPointer = true;
3106
3107 Qualifiers FromQuals = FromType.getQualifiers();
3108 Qualifiers ToQuals = ToType.getQualifiers();
3109
3110 // Ignore __unaligned qualifier if this type is void.
3111 if (ToType.getUnqualifiedType()->isVoidType())
3112 FromQuals.removeUnaligned();
3113
3114 // Objective-C ARC:
3115 // Check Objective-C lifetime conversions.
3116 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() &&
3117 UnwrappedAnyPointer) {
3118 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) {
3119 if (isNonTrivialObjCLifetimeConversion(FromQuals, ToQuals))
3120 ObjCLifetimeConversion = true;
3121 FromQuals.removeObjCLifetime();
3122 ToQuals.removeObjCLifetime();
3123 } else {
3124 // Qualification conversions cannot cast between different
3125 // Objective-C lifetime qualifiers.
3126 return false;
3127 }
3128 }
3129
3130 // Allow addition/removal of GC attributes but not changing GC attributes.
3131 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() &&
3132 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) {
3133 FromQuals.removeObjCGCAttr();
3134 ToQuals.removeObjCGCAttr();
3135 }
3136
3137 // -- for every j > 0, if const is in cv 1,j then const is in cv
3138 // 2,j, and similarly for volatile.
3139 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals))
3140 return false;
3141
3142 // -- if the cv 1,j and cv 2,j are different, then const is in
3143 // every cv for 0 < k < j.
3144 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers()
3145 && !PreviousToQualsIncludeConst)
3146 return false;
3147
3148 // Keep track of whether all prior cv-qualifiers in the "to" type
3149 // include const.
3150 PreviousToQualsIncludeConst
3151 = PreviousToQualsIncludeConst && ToQuals.hasConst();
3152 }
3153
3154 // Allows address space promotion by language rules implemented in
3155 // Type::Qualifiers::isAddressSpaceSupersetOf.
3156 Qualifiers FromQuals = FromType.getQualifiers();
3157 Qualifiers ToQuals = ToType.getQualifiers();
3158 if (!ToQuals.isAddressSpaceSupersetOf(FromQuals) &&
3159 !FromQuals.isAddressSpaceSupersetOf(ToQuals)) {
3160 return false;
3161 }
3162
3163 // We are left with FromType and ToType being the pointee types
3164 // after unwrapping the original FromType and ToType the same number
3165 // of types. If we unwrapped any pointers, and if FromType and
3166 // ToType have the same unqualified type (since we checked
3167 // qualifiers above), then this is a qualification conversion.
3168 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType);
3169}
3170
3171/// - Determine whether this is a conversion from a scalar type to an
3172/// atomic type.
3173///
3174/// If successful, updates \c SCS's second and third steps in the conversion
3175/// sequence to finish the conversion.
3176static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType,
3177 bool InOverloadResolution,
3178 StandardConversionSequence &SCS,
3179 bool CStyle) {
3180 const AtomicType *ToAtomic = ToType->getAs<AtomicType>();
3181 if (!ToAtomic)
3182 return false;
3183
3184 StandardConversionSequence InnerSCS;
3185 if (!IsStandardConversion(S, From, ToAtomic->getValueType(),
3186 InOverloadResolution, InnerSCS,
3187 CStyle, /*AllowObjCWritebackConversion=*/false))
3188 return false;
3189
3190 SCS.Second = InnerSCS.Second;
3191 SCS.setToType(1, InnerSCS.getToType(1));
3192 SCS.Third = InnerSCS.Third;
3193 SCS.QualificationIncludesObjCLifetime
3194 = InnerSCS.QualificationIncludesObjCLifetime;
3195 SCS.setToType(2, InnerSCS.getToType(2));
3196 return true;
3197}
3198
3199static bool isFirstArgumentCompatibleWithType(ASTContext &Context,
3200 CXXConstructorDecl *Constructor,
3201 QualType Type) {
3202 const FunctionProtoType *CtorType =
3203 Constructor->getType()->getAs<FunctionProtoType>();
3204 if (CtorType->getNumParams() > 0) {
3205 QualType FirstArg = CtorType->getParamType(0);
3206 if (Context.hasSameUnqualifiedType(Type, FirstArg.getNonReferenceType()))
3207 return true;
3208 }
3209 return false;
3210}
3211
3212static OverloadingResult
3213IsInitializerListConstructorConversion(Sema &S, Expr *From, QualType ToType,
3214 CXXRecordDecl *To,
3215 UserDefinedConversionSequence &User,
3216 OverloadCandidateSet &CandidateSet,
3217 bool AllowExplicit) {
3218 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3219 for (auto *D : S.LookupConstructors(To)) {
3220 auto Info = getConstructorInfo(D);
3221 if (!Info)
3222 continue;
3223
3224 bool Usable = !Info.Constructor->isInvalidDecl() &&
3225 S.isInitListConstructor(Info.Constructor) &&
3226 (AllowExplicit || !Info.Constructor->isExplicit());
3227 if (Usable) {
3228 // If the first argument is (a reference to) the target type,
3229 // suppress conversions.
3230 bool SuppressUserConversions = isFirstArgumentCompatibleWithType(
3231 S.Context, Info.Constructor, ToType);
3232 if (Info.ConstructorTmpl)
3233 S.AddTemplateOverloadCandidate(Info.ConstructorTmpl, Info.FoundDecl,
3234 /*ExplicitArgs*/ nullptr, From,
3235 CandidateSet, SuppressUserConversions);
3236 else
3237 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl, From,
3238 CandidateSet, SuppressUserConversions);
3239 }
3240 }
3241
3242 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3243
3244 OverloadCandidateSet::iterator Best;
3245 switch (auto Result =
3246 CandidateSet.BestViableFunction(S, From->getBeginLoc(), Best)) {
3247 case OR_Deleted:
3248 case OR_Success: {
3249 // Record the standard conversion we used and the conversion function.
3250 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function);
3251 QualType ThisType = Constructor->getThisType(S.Context);
3252 // Initializer lists don't have conversions as such.
3253 User.Before.setAsIdentityConversion();
3254 User.HadMultipleCandidates = HadMultipleCandidates;
3255 User.ConversionFunction = Constructor;
3256 User.FoundConversionFunction = Best->FoundDecl;
3257 User.After.setAsIdentityConversion();
3258 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType());
3259 User.After.setAllToTypes(ToType);
3260 return Result;
3261 }
3262
3263 case OR_No_Viable_Function:
3264 return OR_No_Viable_Function;
3265 case OR_Ambiguous:
3266 return OR_Ambiguous;
3267 }
3268
3269 llvm_unreachable("Invalid OverloadResult!")::llvm::llvm_unreachable_internal("Invalid OverloadResult!", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3269)
;
3270}
3271
3272/// Determines whether there is a user-defined conversion sequence
3273/// (C++ [over.ics.user]) that converts expression From to the type
3274/// ToType. If such a conversion exists, User will contain the
3275/// user-defined conversion sequence that performs such a conversion
3276/// and this routine will return true. Otherwise, this routine returns
3277/// false and User is unspecified.
3278///
3279/// \param AllowExplicit true if the conversion should consider C++0x
3280/// "explicit" conversion functions as well as non-explicit conversion
3281/// functions (C++0x [class.conv.fct]p2).
3282///
3283/// \param AllowObjCConversionOnExplicit true if the conversion should
3284/// allow an extra Objective-C pointer conversion on uses of explicit
3285/// constructors. Requires \c AllowExplicit to also be set.
3286static OverloadingResult
3287IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
3288 UserDefinedConversionSequence &User,
3289 OverloadCandidateSet &CandidateSet,
3290 bool AllowExplicit,
3291 bool AllowObjCConversionOnExplicit) {
3292 assert(AllowExplicit || !AllowObjCConversionOnExplicit)((AllowExplicit || !AllowObjCConversionOnExplicit) ? static_cast
<void> (0) : __assert_fail ("AllowExplicit || !AllowObjCConversionOnExplicit"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3292, __PRETTY_FUNCTION__))
;
3293 CandidateSet.clear(OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3294
3295 // Whether we will only visit constructors.
3296 bool ConstructorsOnly = false;
3297
3298 // If the type we are conversion to is a class type, enumerate its
3299 // constructors.
3300 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) {
3301 // C++ [over.match.ctor]p1:
3302 // When objects of class type are direct-initialized (8.5), or
3303 // copy-initialized from an expression of the same or a
3304 // derived class type (8.5), overload resolution selects the
3305 // constructor. [...] For copy-initialization, the candidate
3306 // functions are all the converting constructors (12.3.1) of
3307 // that class. The argument list is the expression-list within
3308 // the parentheses of the initializer.
3309 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) ||
3310 (From->getType()->getAs<RecordType>() &&
3311 S.IsDerivedFrom(From->getBeginLoc(), From->getType(), ToType)))
3312 ConstructorsOnly = true;
3313
3314 if (!S.isCompleteType(From->getExprLoc(), ToType)) {
3315 // We're not going to find any constructors.
3316 } else if (CXXRecordDecl *ToRecordDecl
3317 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) {
3318
3319 Expr **Args = &From;
3320 unsigned NumArgs = 1;
3321 bool ListInitializing = false;
3322 if (InitListExpr *InitList = dyn_cast<InitListExpr>(From)) {
3323 // But first, see if there is an init-list-constructor that will work.
3324 OverloadingResult Result = IsInitializerListConstructorConversion(
3325 S, From, ToType, ToRecordDecl, User, CandidateSet, AllowExplicit);
3326 if (Result != OR_No_Viable_Function)
3327 return Result;
3328 // Never mind.
3329 CandidateSet.clear(
3330 OverloadCandidateSet::CSK_InitByUserDefinedConversion);
3331
3332 // If we're list-initializing, we pass the individual elements as
3333 // arguments, not the entire list.
3334 Args = InitList->getInits();
3335 NumArgs = InitList->getNumInits();
3336 ListInitializing = true;
3337 }
3338
3339 for (auto *D : S.LookupConstructors(ToRecordDecl)) {
3340 auto Info = getConstructorInfo(D);
3341 if (!Info)
3342 continue;
3343
3344 bool Usable = !Info.Constructor->isInvalidDecl();
3345 if (ListInitializing)
3346 Usable = Usable && (AllowExplicit || !Info.Constructor->isExplicit());
3347 else
3348 Usable = Usable &&
3349 Info.Constructor->isConvertingConstructor(AllowExplicit);
3350 if (Usable) {
3351 bool SuppressUserConversions = !ConstructorsOnly;
3352 if (SuppressUserConversions && ListInitializing) {
3353 SuppressUserConversions = false;
3354 if (NumArgs == 1) {
3355 // If the first argument is (a reference to) the target type,
3356 // suppress conversions.
3357 SuppressUserConversions = isFirstArgumentCompatibleWithType(
3358 S.Context, Info.Constructor, ToType);
3359 }
3360 }
3361 if (Info.ConstructorTmpl)
3362 S.AddTemplateOverloadCandidate(
3363 Info.ConstructorTmpl, Info.FoundDecl,
3364 /*ExplicitArgs*/ nullptr, llvm::makeArrayRef(Args, NumArgs),
3365 CandidateSet, SuppressUserConversions);
3366 else
3367 // Allow one user-defined conversion when user specifies a
3368 // From->ToType conversion via an static cast (c-style, etc).
3369 S.AddOverloadCandidate(Info.Constructor, Info.FoundDecl,
3370 llvm::makeArrayRef(Args, NumArgs),
3371 CandidateSet, SuppressUserConversions);
3372 }
3373 }
3374 }
3375 }
3376
3377 // Enumerate conversion functions, if we're allowed to.
3378 if (ConstructorsOnly || isa<InitListExpr>(From)) {
3379 } else if (!S.isCompleteType(From->getBeginLoc(), From->getType())) {
3380 // No conversion functions from incomplete types.
3381 } else if (const RecordType *FromRecordType =
3382 From->getType()->getAs<RecordType>()) {
3383 if (CXXRecordDecl *FromRecordDecl
3384 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) {
3385 // Add all of the conversion functions as candidates.
3386 const auto &Conversions = FromRecordDecl->getVisibleConversionFunctions();
3387 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
3388 DeclAccessPair FoundDecl = I.getPair();
3389 NamedDecl *D = FoundDecl.getDecl();
3390 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
3391 if (isa<UsingShadowDecl>(D))
3392 D = cast<UsingShadowDecl>(D)->getTargetDecl();
3393
3394 CXXConversionDecl *Conv;
3395 FunctionTemplateDecl *ConvTemplate;
3396 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D)))
3397 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
3398 else
3399 Conv = cast<CXXConversionDecl>(D);
3400
3401 if (AllowExplicit || !Conv->isExplicit()) {
3402 if (ConvTemplate)
3403 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl,
3404 ActingContext, From, ToType,
3405 CandidateSet,
3406 AllowObjCConversionOnExplicit);
3407 else
3408 S.AddConversionCandidate(Conv, FoundDecl, ActingContext,
3409 From, ToType, CandidateSet,
3410 AllowObjCConversionOnExplicit);
3411 }
3412 }
3413 }
3414 }
3415
3416 bool HadMultipleCandidates = (CandidateSet.size() > 1);
3417
3418 OverloadCandidateSet::iterator Best;
3419 switch (auto Result =
3420 CandidateSet.BestViableFunction(S, From->getBeginLoc(), Best)) {
3421 case OR_Success:
3422 case OR_Deleted:
3423 // Record the standard conversion we used and the conversion function.
3424 if (CXXConstructorDecl *Constructor
3425 = dyn_cast<CXXConstructorDecl>(Best->Function)) {
3426 // C++ [over.ics.user]p1:
3427 // If the user-defined conversion is specified by a
3428 // constructor (12.3.1), the initial standard conversion
3429 // sequence converts the source type to the type required by
3430 // the argument of the constructor.
3431 //
3432 QualType ThisType = Constructor->getThisType(S.Context);
3433 if (isa<InitListExpr>(From)) {
3434 // Initializer lists don't have conversions as such.
3435 User.Before.setAsIdentityConversion();
3436 } else {
3437 if (Best->Conversions[0].isEllipsis())
3438 User.EllipsisConversion = true;
3439 else {
3440 User.Before = Best->Conversions[0].Standard;
3441 User.EllipsisConversion = false;
3442 }
3443 }
3444 User.HadMultipleCandidates = HadMultipleCandidates;
3445 User.ConversionFunction = Constructor;
3446 User.FoundConversionFunction = Best->FoundDecl;
3447 User.After.setAsIdentityConversion();
3448 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType());
3449 User.After.setAllToTypes(ToType);
3450 return Result;
3451 }
3452 if (CXXConversionDecl *Conversion
3453 = dyn_cast<CXXConversionDecl>(Best->Function)) {
3454 // C++ [over.ics.user]p1:
3455 //
3456 // [...] If the user-defined conversion is specified by a
3457 // conversion function (12.3.2), the initial standard
3458 // conversion sequence converts the source type to the
3459 // implicit object parameter of the conversion function.
3460 User.Before = Best->Conversions[0].Standard;
3461 User.HadMultipleCandidates = HadMultipleCandidates;
3462 User.ConversionFunction = Conversion;
3463 User.FoundConversionFunction = Best->FoundDecl;
3464 User.EllipsisConversion = false;
3465
3466 // C++ [over.ics.user]p2:
3467 // The second standard conversion sequence converts the
3468 // result of the user-defined conversion to the target type
3469 // for the sequence. Since an implicit conversion sequence
3470 // is an initialization, the special rules for
3471 // initialization by user-defined conversion apply when
3472 // selecting the best user-defined conversion for a
3473 // user-defined conversion sequence (see 13.3.3 and
3474 // 13.3.3.1).
3475 User.After = Best->FinalConversion;
3476 return Result;
3477 }
3478 llvm_unreachable("Not a constructor or conversion function?")::llvm::llvm_unreachable_internal("Not a constructor or conversion function?"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3478)
;
3479
3480 case OR_No_Viable_Function:
3481 return OR_No_Viable_Function;
3482
3483 case OR_Ambiguous:
3484 return OR_Ambiguous;
3485 }
3486
3487 llvm_unreachable("Invalid OverloadResult!")::llvm::llvm_unreachable_internal("Invalid OverloadResult!", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 3487)
;
3488}
3489
3490bool
3491Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) {
3492 ImplicitConversionSequence ICS;
3493 OverloadCandidateSet CandidateSet(From->getExprLoc(),
3494 OverloadCandidateSet::CSK_Normal);
3495 OverloadingResult OvResult =
3496 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined,
3497 CandidateSet, false, false);
3498 if (OvResult == OR_Ambiguous)
3499 Diag(From->getBeginLoc(), diag::err_typecheck_ambiguous_condition)
3500 << From->getType() << ToType << From->getSourceRange();
3501 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) {
3502 if (!RequireCompleteType(From->getBeginLoc(), ToType,
3503 diag::err_typecheck_nonviable_condition_incomplete,
3504 From->getType(), From->getSourceRange()))
3505 Diag(From->getBeginLoc(), diag::err_typecheck_nonviable_condition)
3506 << false << From->getType() << From->getSourceRange() << ToType;
3507 } else
3508 return false;
3509 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, From);
3510 return true;
3511}
3512
3513/// Compare the user-defined conversion functions or constructors
3514/// of two user-defined conversion sequences to determine whether any ordering
3515/// is possible.
3516static ImplicitConversionSequence::CompareKind
3517compareConversionFunctions(Sema &S, FunctionDecl *Function1,
3518 FunctionDecl *Function2) {
3519 if (!S.getLangOpts().ObjC1 || !S.getLangOpts().CPlusPlus11)
3520 return ImplicitConversionSequence::Indistinguishable;
3521
3522 // Objective-C++:
3523 // If both conversion functions are implicitly-declared conversions from
3524 // a lambda closure type to a function pointer and a block pointer,
3525 // respectively, always prefer the conversion to a function pointer,
3526 // because the function pointer is more lightweight and is more likely
3527 // to keep code working.
3528 CXXConversionDecl *Conv1 = dyn_cast_or_null<CXXConversionDecl>(Function1);
3529 if (!Conv1)
3530 return ImplicitConversionSequence::Indistinguishable;
3531
3532 CXXConversionDecl *Conv2 = dyn_cast<CXXConversionDecl>(Function2);
3533 if (!Conv2)
3534 return ImplicitConversionSequence::Indistinguishable;
3535
3536 if (Conv1->getParent()->isLambda() && Conv2->getParent()->isLambda()) {
3537 bool Block1 = Conv1->getConversionType()->isBlockPointerType();
3538 bool Block2 = Conv2->getConversionType()->isBlockPointerType();
3539 if (Block1 != Block2)
3540 return Block1 ? ImplicitConversionSequence::Worse
3541 : ImplicitConversionSequence::Better;
3542 }
3543
3544 return ImplicitConversionSequence::Indistinguishable;
3545}
3546
3547static bool hasDeprecatedStringLiteralToCharPtrConversion(
3548 const ImplicitConversionSequence &ICS) {
3549 return (ICS.isStandard() && ICS.Standard.DeprecatedStringLiteralToCharPtr) ||
3550 (ICS.isUserDefined() &&
3551 ICS.UserDefined.Before.DeprecatedStringLiteralToCharPtr);
3552}
3553
3554/// CompareImplicitConversionSequences - Compare two implicit
3555/// conversion sequences to determine whether one is better than the
3556/// other or if they are indistinguishable (C++ 13.3.3.2).
3557static ImplicitConversionSequence::CompareKind
3558CompareImplicitConversionSequences(Sema &S, SourceLocation Loc,
3559 const ImplicitConversionSequence& ICS1,
3560 const ImplicitConversionSequence& ICS2)
3561{
3562 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit
3563 // conversion sequences (as defined in 13.3.3.1)
3564 // -- a standard conversion sequence (13.3.3.1.1) is a better
3565 // conversion sequence than a user-defined conversion sequence or
3566 // an ellipsis conversion sequence, and
3567 // -- a user-defined conversion sequence (13.3.3.1.2) is a better
3568 // conversion sequence than an ellipsis conversion sequence
3569 // (13.3.3.1.3).
3570 //
3571 // C++0x [over.best.ics]p10:
3572 // For the purpose of ranking implicit conversion sequences as
3573 // described in 13.3.3.2, the ambiguous conversion sequence is
3574 // treated as a user-defined sequence that is indistinguishable
3575 // from any other user-defined conversion sequence.
3576
3577 // String literal to 'char *' conversion has been deprecated in C++03. It has
3578 // been removed from C++11. We still accept this conversion, if it happens at
3579 // the best viable function. Otherwise, this conversion is considered worse
3580 // than ellipsis conversion. Consider this as an extension; this is not in the
3581 // standard. For example:
3582 //
3583 // int &f(...); // #1
3584 // void f(char*); // #2
3585 // void g() { int &r = f("foo"); }
3586 //
3587 // In C++03, we pick #2 as the best viable function.
3588 // In C++11, we pick #1 as the best viable function, because ellipsis
3589 // conversion is better than string-literal to char* conversion (since there
3590 // is no such conversion in C++11). If there was no #1 at all or #1 couldn't
3591 // convert arguments, #2 would be the best viable function in C++11.
3592 // If the best viable function has this conversion, a warning will be issued
3593 // in C++03, or an ExtWarn (+SFINAE failure) will be issued in C++11.
3594
3595 if (S.getLangOpts().CPlusPlus11 && !S.getLangOpts().WritableStrings &&
3596 hasDeprecatedStringLiteralToCharPtrConversion(ICS1) !=
3597 hasDeprecatedStringLiteralToCharPtrConversion(ICS2))
3598 return hasDeprecatedStringLiteralToCharPtrConversion(ICS1)
3599 ? ImplicitConversionSequence::Worse
3600 : ImplicitConversionSequence::Better;
3601
3602 if (ICS1.getKindRank() < ICS2.getKindRank())
3603 return ImplicitConversionSequence::Better;
3604 if (ICS2.getKindRank() < ICS1.getKindRank())
3605 return ImplicitConversionSequence::Worse;
3606
3607 // The following checks require both conversion sequences to be of
3608 // the same kind.
3609 if (ICS1.getKind() != ICS2.getKind())
3610 return ImplicitConversionSequence::Indistinguishable;
3611
3612 ImplicitConversionSequence::CompareKind Result =
3613 ImplicitConversionSequence::Indistinguishable;
3614
3615 // Two implicit conversion sequences of the same form are
3616 // indistinguishable conversion sequences unless one of the
3617 // following rules apply: (C++ 13.3.3.2p3):
3618
3619 // List-initialization sequence L1 is a better conversion sequence than
3620 // list-initialization sequence L2 if:
3621 // - L1 converts to std::initializer_list<X> for some X and L2 does not, or,
3622 // if not that,
3623 // - L1 converts to type "array of N1 T", L2 converts to type "array of N2 T",
3624 // and N1 is smaller than N2.,
3625 // even if one of the other rules in this paragraph would otherwise apply.
3626 if (!ICS1.isBad()) {
3627 if (ICS1.isStdInitializerListElement() &&
3628 !ICS2.isStdInitializerListElement())
3629 return ImplicitConversionSequence::Better;
3630 if (!ICS1.isStdInitializerListElement() &&
3631 ICS2.isStdInitializerListElement())
3632 return ImplicitConversionSequence::Worse;
3633 }
3634
3635 if (ICS1.isStandard())
3636 // Standard conversion sequence S1 is a better conversion sequence than
3637 // standard conversion sequence S2 if [...]
3638 Result = CompareStandardConversionSequences(S, Loc,
3639 ICS1.Standard, ICS2.Standard);
3640 else if (ICS1.isUserDefined()) {
3641 // User-defined conversion sequence U1 is a better conversion
3642 // sequence than another user-defined conversion sequence U2 if
3643 // they contain the same user-defined conversion function or
3644 // constructor and if the second standard conversion sequence of
3645 // U1 is better than the second standard conversion sequence of
3646 // U2 (C++ 13.3.3.2p3).
3647 if (ICS1.UserDefined.ConversionFunction ==
3648 ICS2.UserDefined.ConversionFunction)
3649 Result = CompareStandardConversionSequences(S, Loc,
3650 ICS1.UserDefined.After,
3651 ICS2.UserDefined.After);
3652 else
3653 Result = compareConversionFunctions(S,
3654 ICS1.UserDefined.ConversionFunction,
3655 ICS2.UserDefined.ConversionFunction);
3656 }
3657
3658 return Result;
3659}
3660
3661// Per 13.3.3.2p3, compare the given standard conversion sequences to
3662// determine if one is a proper subset of the other.
3663static ImplicitConversionSequence::CompareKind
3664compareStandardConversionSubsets(ASTContext &Context,
3665 const StandardConversionSequence& SCS1,
3666 const StandardConversionSequence& SCS2) {
3667 ImplicitConversionSequence::CompareKind Result
3668 = ImplicitConversionSequence::Indistinguishable;
3669
3670 // the identity conversion sequence is considered to be a subsequence of
3671 // any non-identity conversion sequence
3672 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion())
3673 return ImplicitConversionSequence::Better;
3674 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion())
3675 return ImplicitConversionSequence::Worse;
3676
3677 if (SCS1.Second != SCS2.Second) {
3678 if (SCS1.Second == ICK_Identity)
3679 Result = ImplicitConversionSequence::Better;
3680 else if (SCS2.Second == ICK_Identity)
3681 Result = ImplicitConversionSequence::Worse;
3682 else
3683 return ImplicitConversionSequence::Indistinguishable;
3684 } else if (!Context.hasSimilarType(SCS1.getToType(1), SCS2.getToType(1)))
3685 return ImplicitConversionSequence::Indistinguishable;
3686
3687 if (SCS1.Third == SCS2.Third) {
3688 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result
3689 : ImplicitConversionSequence::Indistinguishable;
3690 }
3691
3692 if (SCS1.Third == ICK_Identity)
3693 return Result == ImplicitConversionSequence::Worse
3694 ? ImplicitConversionSequence::Indistinguishable
3695 : ImplicitConversionSequence::Better;
3696
3697 if (SCS2.Third == ICK_Identity)
3698 return Result == ImplicitConversionSequence::Better
3699 ? ImplicitConversionSequence::Indistinguishable
3700 : ImplicitConversionSequence::Worse;
3701
3702 return ImplicitConversionSequence::Indistinguishable;
3703}
3704
3705/// Determine whether one of the given reference bindings is better
3706/// than the other based on what kind of bindings they are.
3707static bool
3708isBetterReferenceBindingKind(const StandardConversionSequence &SCS1,
3709 const StandardConversionSequence &SCS2) {
3710 // C++0x [over.ics.rank]p3b4:
3711 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an
3712 // implicit object parameter of a non-static member function declared
3713 // without a ref-qualifier, and *either* S1 binds an rvalue reference
3714 // to an rvalue and S2 binds an lvalue reference *or S1 binds an
3715 // lvalue reference to a function lvalue and S2 binds an rvalue
3716 // reference*.
3717 //
3718 // FIXME: Rvalue references. We're going rogue with the above edits,
3719 // because the semantics in the current C++0x working paper (N3225 at the
3720 // time of this writing) break the standard definition of std::forward
3721 // and std::reference_wrapper when dealing with references to functions.
3722 // Proposed wording changes submitted to CWG for consideration.
3723 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier ||
3724 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier)
3725 return false;
3726
3727 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue &&
3728 SCS2.IsLvalueReference) ||
3729 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue &&
3730 !SCS2.IsLvalueReference && SCS2.BindsToFunctionLvalue);
3731}
3732
3733/// CompareStandardConversionSequences - Compare two standard
3734/// conversion sequences to determine whether one is better than the
3735/// other or if they are indistinguishable (C++ 13.3.3.2p3).
3736static ImplicitConversionSequence::CompareKind
3737CompareStandardConversionSequences(Sema &S, SourceLocation Loc,
3738 const StandardConversionSequence& SCS1,
3739 const StandardConversionSequence& SCS2)
3740{
3741 // Standard conversion sequence S1 is a better conversion sequence
3742 // than standard conversion sequence S2 if (C++ 13.3.3.2p3):
3743
3744 // -- S1 is a proper subsequence of S2 (comparing the conversion
3745 // sequences in the canonical form defined by 13.3.3.1.1,
3746 // excluding any Lvalue Transformation; the identity conversion
3747 // sequence is considered to be a subsequence of any
3748 // non-identity conversion sequence) or, if not that,
3749 if (ImplicitConversionSequence::CompareKind CK
3750 = compareStandardConversionSubsets(S.Context, SCS1, SCS2))
3751 return CK;
3752
3753 // -- the rank of S1 is better than the rank of S2 (by the rules
3754 // defined below), or, if not that,
3755 ImplicitConversionRank Rank1 = SCS1.getRank();
3756 ImplicitConversionRank Rank2 = SCS2.getRank();
3757 if (Rank1 < Rank2)
3758 return ImplicitConversionSequence::Better;
3759 else if (Rank2 < Rank1)
3760 return ImplicitConversionSequence::Worse;
3761
3762 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank
3763 // are indistinguishable unless one of the following rules
3764 // applies:
3765
3766 // A conversion that is not a conversion of a pointer, or
3767 // pointer to member, to bool is better than another conversion
3768 // that is such a conversion.
3769 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool())
3770 return SCS2.isPointerConversionToBool()
3771 ? ImplicitConversionSequence::Better
3772 : ImplicitConversionSequence::Worse;
3773
3774 // C++ [over.ics.rank]p4b2:
3775 //
3776 // If class B is derived directly or indirectly from class A,
3777 // conversion of B* to A* is better than conversion of B* to
3778 // void*, and conversion of A* to void* is better than conversion
3779 // of B* to void*.
3780 bool SCS1ConvertsToVoid
3781 = SCS1.isPointerConversionToVoidPointer(S.Context);
3782 bool SCS2ConvertsToVoid
3783 = SCS2.isPointerConversionToVoidPointer(S.Context);
3784 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) {
3785 // Exactly one of the conversion sequences is a conversion to
3786 // a void pointer; it's the worse conversion.
3787 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better
3788 : ImplicitConversionSequence::Worse;
3789 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) {
3790 // Neither conversion sequence converts to a void pointer; compare
3791 // their derived-to-base conversions.
3792 if (ImplicitConversionSequence::CompareKind DerivedCK
3793 = CompareDerivedToBaseConversions(S, Loc, SCS1, SCS2))
3794 return DerivedCK;
3795 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid &&
3796 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) {
3797 // Both conversion sequences are conversions to void
3798 // pointers. Compare the source types to determine if there's an
3799 // inheritance relationship in their sources.
3800 QualType FromType1 = SCS1.getFromType();
3801 QualType FromType2 = SCS2.getFromType();
3802
3803 // Adjust the types we're converting from via the array-to-pointer
3804 // conversion, if we need to.
3805 if (SCS1.First == ICK_Array_To_Pointer)
3806 FromType1 = S.Context.getArrayDecayedType(FromType1);
3807 if (SCS2.First == ICK_Array_To_Pointer)
3808 FromType2 = S.Context.getArrayDecayedType(FromType2);
3809
3810 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType();
3811 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType();
3812
3813 if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
3814 return ImplicitConversionSequence::Better;
3815 else if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
3816 return ImplicitConversionSequence::Worse;
3817
3818 // Objective-C++: If one interface is more specific than the
3819 // other, it is the better one.
3820 const ObjCObjectPointerType* FromObjCPtr1
3821 = FromType1->getAs<ObjCObjectPointerType>();
3822 const ObjCObjectPointerType* FromObjCPtr2
3823 = FromType2->getAs<ObjCObjectPointerType>();
3824 if (FromObjCPtr1 && FromObjCPtr2) {
3825 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1,
3826 FromObjCPtr2);
3827 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2,
3828 FromObjCPtr1);
3829 if (AssignLeft != AssignRight) {
3830 return AssignLeft? ImplicitConversionSequence::Better
3831 : ImplicitConversionSequence::Worse;
3832 }
3833 }
3834 }
3835
3836 // Compare based on qualification conversions (C++ 13.3.3.2p3,
3837 // bullet 3).
3838 if (ImplicitConversionSequence::CompareKind QualCK
3839 = CompareQualificationConversions(S, SCS1, SCS2))
3840 return QualCK;
3841
3842 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) {
3843 // Check for a better reference binding based on the kind of bindings.
3844 if (isBetterReferenceBindingKind(SCS1, SCS2))
3845 return ImplicitConversionSequence::Better;
3846 else if (isBetterReferenceBindingKind(SCS2, SCS1))
3847 return ImplicitConversionSequence::Worse;
3848
3849 // C++ [over.ics.rank]p3b4:
3850 // -- S1 and S2 are reference bindings (8.5.3), and the types to
3851 // which the references refer are the same type except for
3852 // top-level cv-qualifiers, and the type to which the reference
3853 // initialized by S2 refers is more cv-qualified than the type
3854 // to which the reference initialized by S1 refers.
3855 QualType T1 = SCS1.getToType(2);
3856 QualType T2 = SCS2.getToType(2);
3857 T1 = S.Context.getCanonicalType(T1);
3858 T2 = S.Context.getCanonicalType(T2);
3859 Qualifiers T1Quals, T2Quals;
3860 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals);
3861 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals);
3862 if (UnqualT1 == UnqualT2) {
3863 // Objective-C++ ARC: If the references refer to objects with different
3864 // lifetimes, prefer bindings that don't change lifetime.
3865 if (SCS1.ObjCLifetimeConversionBinding !=
3866 SCS2.ObjCLifetimeConversionBinding) {
3867 return SCS1.ObjCLifetimeConversionBinding
3868 ? ImplicitConversionSequence::Worse
3869 : ImplicitConversionSequence::Better;
3870 }
3871
3872 // If the type is an array type, promote the element qualifiers to the
3873 // type for comparison.
3874 if (isa<ArrayType>(T1) && T1Quals)
3875 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals);
3876 if (isa<ArrayType>(T2) && T2Quals)
3877 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals);
3878 if (T2.isMoreQualifiedThan(T1))
3879 return ImplicitConversionSequence::Better;
3880 else if (T1.isMoreQualifiedThan(T2))
3881 return ImplicitConversionSequence::Worse;
3882 }
3883 }
3884
3885 // In Microsoft mode, prefer an integral conversion to a
3886 // floating-to-integral conversion if the integral conversion
3887 // is between types of the same size.
3888 // For example:
3889 // void f(float);
3890 // void f(int);
3891 // int main {
3892 // long a;
3893 // f(a);
3894 // }
3895 // Here, MSVC will call f(int) instead of generating a compile error
3896 // as clang will do in standard mode.
3897 if (S.getLangOpts().MSVCCompat && SCS1.Second == ICK_Integral_Conversion &&
3898 SCS2.Second == ICK_Floating_Integral &&
3899 S.Context.getTypeSize(SCS1.getFromType()) ==
3900 S.Context.getTypeSize(SCS1.getToType(2)))
3901 return ImplicitConversionSequence::Better;
3902
3903 return ImplicitConversionSequence::Indistinguishable;
3904}
3905
3906/// CompareQualificationConversions - Compares two standard conversion
3907/// sequences to determine whether they can be ranked based on their
3908/// qualification conversions (C++ 13.3.3.2p3 bullet 3).
3909static ImplicitConversionSequence::CompareKind
3910CompareQualificationConversions(Sema &S,
3911 const StandardConversionSequence& SCS1,
3912 const StandardConversionSequence& SCS2) {
3913 // C++ 13.3.3.2p3:
3914 // -- S1 and S2 differ only in their qualification conversion and
3915 // yield similar types T1 and T2 (C++ 4.4), respectively, and the
3916 // cv-qualification signature of type T1 is a proper subset of
3917 // the cv-qualification signature of type T2, and S1 is not the
3918 // deprecated string literal array-to-pointer conversion (4.2).
3919 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second ||
3920 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification)
3921 return ImplicitConversionSequence::Indistinguishable;
3922
3923 // FIXME: the example in the standard doesn't use a qualification
3924 // conversion (!)
3925 QualType T1 = SCS1.getToType(2);
3926 QualType T2 = SCS2.getToType(2);
3927 T1 = S.Context.getCanonicalType(T1);
3928 T2 = S.Context.getCanonicalType(T2);
3929 Qualifiers T1Quals, T2Quals;
3930 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals);
3931 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals);
3932
3933 // If the types are the same, we won't learn anything by unwrapped
3934 // them.
3935 if (UnqualT1 == UnqualT2)
3936 return ImplicitConversionSequence::Indistinguishable;
3937
3938 // If the type is an array type, promote the element qualifiers to the type
3939 // for comparison.
3940 if (isa<ArrayType>(T1) && T1Quals)
3941 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals);
3942 if (isa<ArrayType>(T2) && T2Quals)
3943 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals);
3944
3945 ImplicitConversionSequence::CompareKind Result
3946 = ImplicitConversionSequence::Indistinguishable;
3947
3948 // Objective-C++ ARC:
3949 // Prefer qualification conversions not involving a change in lifetime
3950 // to qualification conversions that do not change lifetime.
3951 if (SCS1.QualificationIncludesObjCLifetime !=
3952 SCS2.QualificationIncludesObjCLifetime) {
3953 Result = SCS1.QualificationIncludesObjCLifetime
3954 ? ImplicitConversionSequence::Worse
3955 : ImplicitConversionSequence::Better;
3956 }
3957
3958 while (S.Context.UnwrapSimilarTypes(T1, T2)) {
3959 // Within each iteration of the loop, we check the qualifiers to
3960 // determine if this still looks like a qualification
3961 // conversion. Then, if all is well, we unwrap one more level of
3962 // pointers or pointers-to-members and do it all again
3963 // until there are no more pointers or pointers-to-members left
3964 // to unwrap. This essentially mimics what
3965 // IsQualificationConversion does, but here we're checking for a
3966 // strict subset of qualifiers.
3967 if (T1.getCVRQualifiers() == T2.getCVRQualifiers())
3968 // The qualifiers are the same, so this doesn't tell us anything
3969 // about how the sequences rank.
3970 ;
3971 else if (T2.isMoreQualifiedThan(T1)) {
3972 // T1 has fewer qualifiers, so it could be the better sequence.
3973 if (Result == ImplicitConversionSequence::Worse)
3974 // Neither has qualifiers that are a subset of the other's
3975 // qualifiers.
3976 return ImplicitConversionSequence::Indistinguishable;
3977
3978 Result = ImplicitConversionSequence::Better;
3979 } else if (T1.isMoreQualifiedThan(T2)) {
3980 // T2 has fewer qualifiers, so it could be the better sequence.
3981 if (Result == ImplicitConversionSequence::Better)
3982 // Neither has qualifiers that are a subset of the other's
3983 // qualifiers.
3984 return ImplicitConversionSequence::Indistinguishable;
3985
3986 Result = ImplicitConversionSequence::Worse;
3987 } else {
3988 // Qualifiers are disjoint.
3989 return ImplicitConversionSequence::Indistinguishable;
3990 }
3991
3992 // If the types after this point are equivalent, we're done.
3993 if (S.Context.hasSameUnqualifiedType(T1, T2))
3994 break;
3995 }
3996
3997 // Check that the winning standard conversion sequence isn't using
3998 // the deprecated string literal array to pointer conversion.
3999 switch (Result) {
4000 case ImplicitConversionSequence::Better:
4001 if (SCS1.DeprecatedStringLiteralToCharPtr)
4002 Result = ImplicitConversionSequence::Indistinguishable;
4003 break;
4004
4005 case ImplicitConversionSequence::Indistinguishable:
4006 break;
4007
4008 case ImplicitConversionSequence::Worse:
4009 if (SCS2.DeprecatedStringLiteralToCharPtr)
4010 Result = ImplicitConversionSequence::Indistinguishable;
4011 break;
4012 }
4013
4014 return Result;
4015}
4016
4017/// CompareDerivedToBaseConversions - Compares two standard conversion
4018/// sequences to determine whether they can be ranked based on their
4019/// various kinds of derived-to-base conversions (C++
4020/// [over.ics.rank]p4b3). As part of these checks, we also look at
4021/// conversions between Objective-C interface types.
4022static ImplicitConversionSequence::CompareKind
4023CompareDerivedToBaseConversions(Sema &S, SourceLocation Loc,
4024 const StandardConversionSequence& SCS1,
4025 const StandardConversionSequence& SCS2) {
4026 QualType FromType1 = SCS1.getFromType();
4027 QualType ToType1 = SCS1.getToType(1);
4028 QualType FromType2 = SCS2.getFromType();
4029 QualType ToType2 = SCS2.getToType(1);
4030
4031 // Adjust the types we're converting from via the array-to-pointer
4032 // conversion, if we need to.
4033 if (SCS1.First == ICK_Array_To_Pointer)
4034 FromType1 = S.Context.getArrayDecayedType(FromType1);
4035 if (SCS2.First == ICK_Array_To_Pointer)
4036 FromType2 = S.Context.getArrayDecayedType(FromType2);
4037
4038 // Canonicalize all of the types.
4039 FromType1 = S.Context.getCanonicalType(FromType1);
4040 ToType1 = S.Context.getCanonicalType(ToType1);
4041 FromType2 = S.Context.getCanonicalType(FromType2);
4042 ToType2 = S.Context.getCanonicalType(ToType2);
4043
4044 // C++ [over.ics.rank]p4b3:
4045 //
4046 // If class B is derived directly or indirectly from class A and
4047 // class C is derived directly or indirectly from B,
4048 //
4049 // Compare based on pointer conversions.
4050 if (SCS1.Second == ICK_Pointer_Conversion &&
4051 SCS2.Second == ICK_Pointer_Conversion &&
4052 /*FIXME: Remove if Objective-C id conversions get their own rank*/
4053 FromType1->isPointerType() && FromType2->isPointerType() &&
4054 ToType1->isPointerType() && ToType2->isPointerType()) {
4055 QualType FromPointee1
4056 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType();
4057 QualType ToPointee1
4058 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType();
4059 QualType FromPointee2
4060 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType();
4061 QualType ToPointee2
4062 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType();
4063
4064 // -- conversion of C* to B* is better than conversion of C* to A*,
4065 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) {
4066 if (S.IsDerivedFrom(Loc, ToPointee1, ToPointee2))
4067 return ImplicitConversionSequence::Better;
4068 else if (S.IsDerivedFrom(Loc, ToPointee2, ToPointee1))
4069 return ImplicitConversionSequence::Worse;
4070 }
4071
4072 // -- conversion of B* to A* is better than conversion of C* to A*,
4073 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) {
4074 if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
4075 return ImplicitConversionSequence::Better;
4076 else if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
4077 return ImplicitConversionSequence::Worse;
4078 }
4079 } else if (SCS1.Second == ICK_Pointer_Conversion &&
4080 SCS2.Second == ICK_Pointer_Conversion) {
4081 const ObjCObjectPointerType *FromPtr1
4082 = FromType1->getAs<ObjCObjectPointerType>();
4083 const ObjCObjectPointerType *FromPtr2
4084 = FromType2->getAs<ObjCObjectPointerType>();
4085 const ObjCObjectPointerType *ToPtr1
4086 = ToType1->getAs<ObjCObjectPointerType>();
4087 const ObjCObjectPointerType *ToPtr2
4088 = ToType2->getAs<ObjCObjectPointerType>();
4089
4090 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) {
4091 // Apply the same conversion ranking rules for Objective-C pointer types
4092 // that we do for C++ pointers to class types. However, we employ the
4093 // Objective-C pseudo-subtyping relationship used for assignment of
4094 // Objective-C pointer types.
4095 bool FromAssignLeft
4096 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2);
4097 bool FromAssignRight
4098 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1);
4099 bool ToAssignLeft
4100 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2);
4101 bool ToAssignRight
4102 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1);
4103
4104 // A conversion to an a non-id object pointer type or qualified 'id'
4105 // type is better than a conversion to 'id'.
4106 if (ToPtr1->isObjCIdType() &&
4107 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl()))
4108 return ImplicitConversionSequence::Worse;
4109 if (ToPtr2->isObjCIdType() &&
4110 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl()))
4111 return ImplicitConversionSequence::Better;
4112
4113 // A conversion to a non-id object pointer type is better than a
4114 // conversion to a qualified 'id' type
4115 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl())
4116 return ImplicitConversionSequence::Worse;
4117 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl())
4118 return ImplicitConversionSequence::Better;
4119
4120 // A conversion to an a non-Class object pointer type or qualified 'Class'
4121 // type is better than a conversion to 'Class'.
4122 if (ToPtr1->isObjCClassType() &&
4123 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl()))
4124 return ImplicitConversionSequence::Worse;
4125 if (ToPtr2->isObjCClassType() &&
4126 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl()))
4127 return ImplicitConversionSequence::Better;
4128
4129 // A conversion to a non-Class object pointer type is better than a
4130 // conversion to a qualified 'Class' type.
4131 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl())
4132 return ImplicitConversionSequence::Worse;
4133 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl())
4134 return ImplicitConversionSequence::Better;
4135
4136 // -- "conversion of C* to B* is better than conversion of C* to A*,"
4137 if (S.Context.hasSameType(FromType1, FromType2) &&
4138 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() &&
4139 (ToAssignLeft != ToAssignRight)) {
4140 if (FromPtr1->isSpecialized()) {
4141 // "conversion of B<A> * to B * is better than conversion of B * to
4142 // C *.
4143 bool IsFirstSame =
4144 FromPtr1->getInterfaceDecl() == ToPtr1->getInterfaceDecl();
4145 bool IsSecondSame =
4146 FromPtr1->getInterfaceDecl() == ToPtr2->getInterfaceDecl();
4147 if (IsFirstSame) {
4148 if (!IsSecondSame)
4149 return ImplicitConversionSequence::Better;
4150 } else if (IsSecondSame)
4151 return ImplicitConversionSequence::Worse;
4152 }
4153 return ToAssignLeft? ImplicitConversionSequence::Worse
4154 : ImplicitConversionSequence::Better;
4155 }
4156
4157 // -- "conversion of B* to A* is better than conversion of C* to A*,"
4158 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) &&
4159 (FromAssignLeft != FromAssignRight))
4160 return FromAssignLeft? ImplicitConversionSequence::Better
4161 : ImplicitConversionSequence::Worse;
4162 }
4163 }
4164
4165 // Ranking of member-pointer types.
4166 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member &&
4167 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() &&
4168 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) {
4169 const MemberPointerType * FromMemPointer1 =
4170 FromType1->getAs<MemberPointerType>();
4171 const MemberPointerType * ToMemPointer1 =
4172 ToType1->getAs<MemberPointerType>();
4173 const MemberPointerType * FromMemPointer2 =
4174 FromType2->getAs<MemberPointerType>();
4175 const MemberPointerType * ToMemPointer2 =
4176 ToType2->getAs<MemberPointerType>();
4177 const Type *FromPointeeType1 = FromMemPointer1->getClass();
4178 const Type *ToPointeeType1 = ToMemPointer1->getClass();
4179 const Type *FromPointeeType2 = FromMemPointer2->getClass();
4180 const Type *ToPointeeType2 = ToMemPointer2->getClass();
4181 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType();
4182 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType();
4183 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType();
4184 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType();
4185 // conversion of A::* to B::* is better than conversion of A::* to C::*,
4186 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) {
4187 if (S.IsDerivedFrom(Loc, ToPointee1, ToPointee2))
4188 return ImplicitConversionSequence::Worse;
4189 else if (S.IsDerivedFrom(Loc, ToPointee2, ToPointee1))
4190 return ImplicitConversionSequence::Better;
4191 }
4192 // conversion of B::* to C::* is better than conversion of A::* to C::*
4193 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) {
4194 if (S.IsDerivedFrom(Loc, FromPointee1, FromPointee2))
4195 return ImplicitConversionSequence::Better;
4196 else if (S.IsDerivedFrom(Loc, FromPointee2, FromPointee1))
4197 return ImplicitConversionSequence::Worse;
4198 }
4199 }
4200
4201 if (SCS1.Second == ICK_Derived_To_Base) {
4202 // -- conversion of C to B is better than conversion of C to A,
4203 // -- binding of an expression of type C to a reference of type
4204 // B& is better than binding an expression of type C to a
4205 // reference of type A&,
4206 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) &&
4207 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) {
4208 if (S.IsDerivedFrom(Loc, ToType1, ToType2))
4209 return ImplicitConversionSequence::Better;
4210 else if (S.IsDerivedFrom(Loc, ToType2, ToType1))
4211 return ImplicitConversionSequence::Worse;
4212 }
4213
4214 // -- conversion of B to A is better than conversion of C to A.
4215 // -- binding of an expression of type B to a reference of type
4216 // A& is better than binding an expression of type C to a
4217 // reference of type A&,
4218 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) &&
4219 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) {
4220 if (S.IsDerivedFrom(Loc, FromType2, FromType1))
4221 return ImplicitConversionSequence::Better;
4222 else if (S.IsDerivedFrom(Loc, FromType1, FromType2))
4223 return ImplicitConversionSequence::Worse;
4224 }
4225 }
4226
4227 return ImplicitConversionSequence::Indistinguishable;
4228}
4229
4230/// Determine whether the given type is valid, e.g., it is not an invalid
4231/// C++ class.
4232static bool isTypeValid(QualType T) {
4233 if (CXXRecordDecl *Record = T->getAsCXXRecordDecl())
4234 return !Record->isInvalidDecl();
4235
4236 return true;
4237}
4238
4239/// CompareReferenceRelationship - Compare the two types T1 and T2 to
4240/// determine whether they are reference-related,
4241/// reference-compatible, reference-compatible with added
4242/// qualification, or incompatible, for use in C++ initialization by
4243/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference
4244/// type, and the first type (T1) is the pointee type of the reference
4245/// type being initialized.
4246Sema::ReferenceCompareResult
4247Sema::CompareReferenceRelationship(SourceLocation Loc,
4248 QualType OrigT1, QualType OrigT2,
4249 bool &DerivedToBase,
4250 bool &ObjCConversion,
4251 bool &ObjCLifetimeConversion) {
4252 assert(!OrigT1->isReferenceType() &&((!OrigT1->isReferenceType() && "T1 must be the pointee type of the reference type"
) ? static_cast<void> (0) : __assert_fail ("!OrigT1->isReferenceType() && \"T1 must be the pointee type of the reference type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4253, __PRETTY_FUNCTION__))
4253 "T1 must be the pointee type of the reference type")((!OrigT1->isReferenceType() && "T1 must be the pointee type of the reference type"
) ? static_cast<void> (0) : __assert_fail ("!OrigT1->isReferenceType() && \"T1 must be the pointee type of the reference type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4253, __PRETTY_FUNCTION__))
;
4254 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type")((!OrigT2->isReferenceType() && "T2 cannot be a reference type"
) ? static_cast<void> (0) : __assert_fail ("!OrigT2->isReferenceType() && \"T2 cannot be a reference type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4254, __PRETTY_FUNCTION__))
;
4255
4256 QualType T1 = Context.getCanonicalType(OrigT1);
4257 QualType T2 = Context.getCanonicalType(OrigT2);
4258 Qualifiers T1Quals, T2Quals;
4259 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals);
4260 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals);
4261
4262 // C++ [dcl.init.ref]p4:
4263 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is
4264 // reference-related to "cv2 T2" if T1 is the same type as T2, or
4265 // T1 is a base class of T2.
4266 DerivedToBase = false;
4267 ObjCConversion = false;
4268 ObjCLifetimeConversion = false;
4269 QualType ConvertedT2;
4270 if (UnqualT1 == UnqualT2) {
4271 // Nothing to do.
4272 } else if (isCompleteType(Loc, OrigT2) &&
4273 isTypeValid(UnqualT1) && isTypeValid(UnqualT2) &&
4274 IsDerivedFrom(Loc, UnqualT2, UnqualT1))
4275 DerivedToBase = true;
4276 else if (UnqualT1->isObjCObjectOrInterfaceType() &&
4277 UnqualT2->isObjCObjectOrInterfaceType() &&
4278 Context.canBindObjCObjectType(UnqualT1, UnqualT2))
4279 ObjCConversion = true;
4280 else if (UnqualT2->isFunctionType() &&
4281 IsFunctionConversion(UnqualT2, UnqualT1, ConvertedT2))
4282 // C++1z [dcl.init.ref]p4:
4283 // cv1 T1" is reference-compatible with "cv2 T2" if [...] T2 is "noexcept
4284 // function" and T1 is "function"
4285 //
4286 // We extend this to also apply to 'noreturn', so allow any function
4287 // conversion between function types.
4288 return Ref_Compatible;
4289 else
4290 return Ref_Incompatible;
4291
4292 // At this point, we know that T1 and T2 are reference-related (at
4293 // least).
4294
4295 // If the type is an array type, promote the element qualifiers to the type
4296 // for comparison.
4297 if (isa<ArrayType>(T1) && T1Quals)
4298 T1 = Context.getQualifiedType(UnqualT1, T1Quals);
4299 if (isa<ArrayType>(T2) && T2Quals)
4300 T2 = Context.getQualifiedType(UnqualT2, T2Quals);
4301
4302 // C++ [dcl.init.ref]p4:
4303 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is
4304 // reference-related to T2 and cv1 is the same cv-qualification
4305 // as, or greater cv-qualification than, cv2. For purposes of
4306 // overload resolution, cases for which cv1 is greater
4307 // cv-qualification than cv2 are identified as
4308 // reference-compatible with added qualification (see 13.3.3.2).
4309 //
4310 // Note that we also require equivalence of Objective-C GC and address-space
4311 // qualifiers when performing these computations, so that e.g., an int in
4312 // address space 1 is not reference-compatible with an int in address
4313 // space 2.
4314 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() &&
4315 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) {
4316 if (isNonTrivialObjCLifetimeConversion(T2Quals, T1Quals))
4317 ObjCLifetimeConversion = true;
4318
4319 T1Quals.removeObjCLifetime();
4320 T2Quals.removeObjCLifetime();
4321 }
4322
4323 // MS compiler ignores __unaligned qualifier for references; do the same.
4324 T1Quals.removeUnaligned();
4325 T2Quals.removeUnaligned();
4326
4327 if (T1Quals.compatiblyIncludes(T2Quals))
4328 return Ref_Compatible;
4329 else
4330 return Ref_Related;
4331}
4332
4333/// Look for a user-defined conversion to a value reference-compatible
4334/// with DeclType. Return true if something definite is found.
4335static bool
4336FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS,
4337 QualType DeclType, SourceLocation DeclLoc,
4338 Expr *Init, QualType T2, bool AllowRvalues,
4339 bool AllowExplicit) {
4340 assert(T2->isRecordType() && "Can only find conversions of record types.")((T2->isRecordType() && "Can only find conversions of record types."
) ? static_cast<void> (0) : __assert_fail ("T2->isRecordType() && \"Can only find conversions of record types.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4340, __PRETTY_FUNCTION__))
;
4341 CXXRecordDecl *T2RecordDecl
4342 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl());
4343
4344 OverloadCandidateSet CandidateSet(
4345 DeclLoc, OverloadCandidateSet::CSK_InitByUserDefinedConversion);
4346 const auto &Conversions = T2RecordDecl->getVisibleConversionFunctions();
4347 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
4348 NamedDecl *D = *I;
4349 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext());
4350 if (isa<UsingShadowDecl>(D))
4351 D = cast<UsingShadowDecl>(D)->getTargetDecl();
4352
4353 FunctionTemplateDecl *ConvTemplate
4354 = dyn_cast<FunctionTemplateDecl>(D);
4355 CXXConversionDecl *Conv;
4356 if (ConvTemplate)
4357 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
4358 else
4359 Conv = cast<CXXConversionDecl>(D);
4360
4361 // If this is an explicit conversion, and we're not allowed to consider
4362 // explicit conversions, skip it.
4363 if (!AllowExplicit && Conv->isExplicit())
4364 continue;
4365
4366 if (AllowRvalues) {
4367 bool DerivedToBase = false;
4368 bool ObjCConversion = false;
4369 bool ObjCLifetimeConversion = false;
4370
4371 // If we are initializing an rvalue reference, don't permit conversion
4372 // functions that return lvalues.
4373 if (!ConvTemplate && DeclType->isRValueReferenceType()) {
4374 const ReferenceType *RefType
4375 = Conv->getConversionType()->getAs<LValueReferenceType>();
4376 if (RefType && !RefType->getPointeeType()->isFunctionType())
4377 continue;
4378 }
4379
4380 if (!ConvTemplate &&
4381 S.CompareReferenceRelationship(
4382 DeclLoc,
4383 Conv->getConversionType().getNonReferenceType()
4384 .getUnqualifiedType(),
4385 DeclType.getNonReferenceType().getUnqualifiedType(),
4386 DerivedToBase, ObjCConversion, ObjCLifetimeConversion) ==
4387 Sema::Ref_Incompatible)
4388 continue;
4389 } else {
4390 // If the conversion function doesn't return a reference type,
4391 // it can't be considered for this conversion. An rvalue reference
4392 // is only acceptable if its referencee is a function type.
4393
4394 const ReferenceType *RefType =
4395 Conv->getConversionType()->getAs<ReferenceType>();
4396 if (!RefType ||
4397 (!RefType->isLValueReferenceType() &&
4398 !RefType->getPointeeType()->isFunctionType()))
4399 continue;
4400 }
4401
4402 if (ConvTemplate)
4403 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC,
4404 Init, DeclType, CandidateSet,
4405 /*AllowObjCConversionOnExplicit=*/false);
4406 else
4407 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init,
4408 DeclType, CandidateSet,
4409 /*AllowObjCConversionOnExplicit=*/false);
4410 }
4411
4412 bool HadMultipleCandidates = (CandidateSet.size() > 1);
4413
4414 OverloadCandidateSet::iterator Best;
4415 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best)) {
4416 case OR_Success:
4417 // C++ [over.ics.ref]p1:
4418 //
4419 // [...] If the parameter binds directly to the result of
4420 // applying a conversion function to the argument
4421 // expression, the implicit conversion sequence is a
4422 // user-defined conversion sequence (13.3.3.1.2), with the
4423 // second standard conversion sequence either an identity
4424 // conversion or, if the conversion function returns an
4425 // entity of a type that is a derived class of the parameter
4426 // type, a derived-to-base Conversion.
4427 if (!Best->FinalConversion.DirectBinding)
4428 return false;
4429
4430 ICS.setUserDefined();
4431 ICS.UserDefined.Before = Best->Conversions[0].Standard;
4432 ICS.UserDefined.After = Best->FinalConversion;
4433 ICS.UserDefined.HadMultipleCandidates = HadMultipleCandidates;
4434 ICS.UserDefined.ConversionFunction = Best->Function;
4435 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl;
4436 ICS.UserDefined.EllipsisConversion = false;
4437 assert(ICS.UserDefined.After.ReferenceBinding &&((ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined
.After.DirectBinding && "Expected a direct reference binding!"
) ? static_cast<void> (0) : __assert_fail ("ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined.After.DirectBinding && \"Expected a direct reference binding!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4439, __PRETTY_FUNCTION__))
4438 ICS.UserDefined.After.DirectBinding &&((ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined
.After.DirectBinding && "Expected a direct reference binding!"
) ? static_cast<void> (0) : __assert_fail ("ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined.After.DirectBinding && \"Expected a direct reference binding!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4439, __PRETTY_FUNCTION__))
4439 "Expected a direct reference binding!")((ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined
.After.DirectBinding && "Expected a direct reference binding!"
) ? static_cast<void> (0) : __assert_fail ("ICS.UserDefined.After.ReferenceBinding && ICS.UserDefined.After.DirectBinding && \"Expected a direct reference binding!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4439, __PRETTY_FUNCTION__))
;
4440 return true;
4441
4442 case OR_Ambiguous:
4443 ICS.setAmbiguous();
4444 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
4445 Cand != CandidateSet.end(); ++Cand)
4446 if (Cand->Viable)
4447 ICS.Ambiguous.addConversion(Cand->FoundDecl, Cand->Function);
4448 return true;
4449
4450 case OR_No_Viable_Function:
4451 case OR_Deleted:
4452 // There was no suitable conversion, or we found a deleted
4453 // conversion; continue with other checks.
4454 return false;
4455 }
4456
4457 llvm_unreachable("Invalid OverloadResult!")::llvm::llvm_unreachable_internal("Invalid OverloadResult!", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4457)
;
4458}
4459
4460/// Compute an implicit conversion sequence for reference
4461/// initialization.
4462static ImplicitConversionSequence
4463TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
4464 SourceLocation DeclLoc,
4465 bool SuppressUserConversions,
4466 bool AllowExplicit) {
4467 assert(DeclType->isReferenceType() && "Reference init needs a reference")((DeclType->isReferenceType() && "Reference init needs a reference"
) ? static_cast<void> (0) : __assert_fail ("DeclType->isReferenceType() && \"Reference init needs a reference\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4467, __PRETTY_FUNCTION__))
;
4468
4469 // Most paths end in a failed conversion.
4470 ImplicitConversionSequence ICS;
4471 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType);
4472
4473 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType();
4474 QualType T2 = Init->getType();
4475
4476 // If the initializer is the address of an overloaded function, try
4477 // to resolve the overloaded function. If all goes well, T2 is the
4478 // type of the resulting function.
4479 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) {
4480 DeclAccessPair Found;
4481 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType,
4482 false, Found))
4483 T2 = Fn->getType();
4484 }
4485
4486 // Compute some basic properties of the types and the initializer.
4487 bool isRValRef = DeclType->isRValueReferenceType();
4488 bool DerivedToBase = false;
4489 bool ObjCConversion = false;
4490 bool ObjCLifetimeConversion = false;
4491 Expr::Classification InitCategory = Init->Classify(S.Context);
4492 Sema::ReferenceCompareResult RefRelationship
4493 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase,
4494 ObjCConversion, ObjCLifetimeConversion);
4495
4496
4497 // C++0x [dcl.init.ref]p5:
4498 // A reference to type "cv1 T1" is initialized by an expression
4499 // of type "cv2 T2" as follows:
4500
4501 // -- If reference is an lvalue reference and the initializer expression
4502 if (!isRValRef) {
4503 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is
4504 // reference-compatible with "cv2 T2," or
4505 //
4506 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here.
4507 if (InitCategory.isLValue() && RefRelationship == Sema::Ref_Compatible) {
4508 // C++ [over.ics.ref]p1:
4509 // When a parameter of reference type binds directly (8.5.3)
4510 // to an argument expression, the implicit conversion sequence
4511 // is the identity conversion, unless the argument expression
4512 // has a type that is a derived class of the parameter type,
4513 // in which case the implicit conversion sequence is a
4514 // derived-to-base Conversion (13.3.3.1).
4515 ICS.setStandard();
4516 ICS.Standard.First = ICK_Identity;
4517 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base
4518 : ObjCConversion? ICK_Compatible_Conversion
4519 : ICK_Identity;
4520 ICS.Standard.Third = ICK_Identity;
4521 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr();
4522 ICS.Standard.setToType(0, T2);
4523 ICS.Standard.setToType(1, T1);
4524 ICS.Standard.setToType(2, T1);
4525 ICS.Standard.ReferenceBinding = true;
4526 ICS.Standard.DirectBinding = true;
4527 ICS.Standard.IsLvalueReference = !isRValRef;
4528 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
4529 ICS.Standard.BindsToRvalue = false;
4530 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4531 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion;
4532 ICS.Standard.CopyConstructor = nullptr;
4533 ICS.Standard.DeprecatedStringLiteralToCharPtr = false;
4534
4535 // Nothing more to do: the inaccessibility/ambiguity check for
4536 // derived-to-base conversions is suppressed when we're
4537 // computing the implicit conversion sequence (C++
4538 // [over.best.ics]p2).
4539 return ICS;
4540 }
4541
4542 // -- has a class type (i.e., T2 is a class type), where T1 is
4543 // not reference-related to T2, and can be implicitly
4544 // converted to an lvalue of type "cv3 T3," where "cv1 T1"
4545 // is reference-compatible with "cv3 T3" 92) (this
4546 // conversion is selected by enumerating the applicable
4547 // conversion functions (13.3.1.6) and choosing the best
4548 // one through overload resolution (13.3)),
4549 if (!SuppressUserConversions && T2->isRecordType() &&
4550 S.isCompleteType(DeclLoc, T2) &&
4551 RefRelationship == Sema::Ref_Incompatible) {
4552 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
4553 Init, T2, /*AllowRvalues=*/false,
4554 AllowExplicit))
4555 return ICS;
4556 }
4557 }
4558
4559 // -- Otherwise, the reference shall be an lvalue reference to a
4560 // non-volatile const type (i.e., cv1 shall be const), or the reference
4561 // shall be an rvalue reference.
4562 if (!isRValRef && (!T1.isConstQualified() || T1.isVolatileQualified()))
4563 return ICS;
4564
4565 // -- If the initializer expression
4566 //
4567 // -- is an xvalue, class prvalue, array prvalue or function
4568 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or
4569 if (RefRelationship == Sema::Ref_Compatible &&
4570 (InitCategory.isXValue() ||
4571 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) ||
4572 (InitCategory.isLValue() && T2->isFunctionType()))) {
4573 ICS.setStandard();
4574 ICS.Standard.First = ICK_Identity;
4575 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base
4576 : ObjCConversion? ICK_Compatible_Conversion
4577 : ICK_Identity;
4578 ICS.Standard.Third = ICK_Identity;
4579 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr();
4580 ICS.Standard.setToType(0, T2);
4581 ICS.Standard.setToType(1, T1);
4582 ICS.Standard.setToType(2, T1);
4583 ICS.Standard.ReferenceBinding = true;
4584 // In C++0x, this is always a direct binding. In C++98/03, it's a direct
4585 // binding unless we're binding to a class prvalue.
4586 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we
4587 // allow the use of rvalue references in C++98/03 for the benefit of
4588 // standard library implementors; therefore, we need the xvalue check here.
4589 ICS.Standard.DirectBinding =
4590 S.getLangOpts().CPlusPlus11 ||
4591 !(InitCategory.isPRValue() || T2->isRecordType());
4592 ICS.Standard.IsLvalueReference = !isRValRef;
4593 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType();
4594 ICS.Standard.BindsToRvalue = InitCategory.isRValue();
4595 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4596 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion;
4597 ICS.Standard.CopyConstructor = nullptr;
4598 ICS.Standard.DeprecatedStringLiteralToCharPtr = false;
4599 return ICS;
4600 }
4601
4602 // -- has a class type (i.e., T2 is a class type), where T1 is not
4603 // reference-related to T2, and can be implicitly converted to
4604 // an xvalue, class prvalue, or function lvalue of type
4605 // "cv3 T3", where "cv1 T1" is reference-compatible with
4606 // "cv3 T3",
4607 //
4608 // then the reference is bound to the value of the initializer
4609 // expression in the first case and to the result of the conversion
4610 // in the second case (or, in either case, to an appropriate base
4611 // class subobject).
4612 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible &&
4613 T2->isRecordType() && S.isCompleteType(DeclLoc, T2) &&
4614 FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
4615 Init, T2, /*AllowRvalues=*/true,
4616 AllowExplicit)) {
4617 // In the second case, if the reference is an rvalue reference
4618 // and the second standard conversion sequence of the
4619 // user-defined conversion sequence includes an lvalue-to-rvalue
4620 // conversion, the program is ill-formed.
4621 if (ICS.isUserDefined() && isRValRef &&
4622 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue)
4623 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType);
4624
4625 return ICS;
4626 }
4627
4628 // A temporary of function type cannot be created; don't even try.
4629 if (T1->isFunctionType())
4630 return ICS;
4631
4632 // -- Otherwise, a temporary of type "cv1 T1" is created and
4633 // initialized from the initializer expression using the
4634 // rules for a non-reference copy initialization (8.5). The
4635 // reference is then bound to the temporary. If T1 is
4636 // reference-related to T2, cv1 must be the same
4637 // cv-qualification as, or greater cv-qualification than,
4638 // cv2; otherwise, the program is ill-formed.
4639 if (RefRelationship == Sema::Ref_Related) {
4640 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then
4641 // we would be reference-compatible or reference-compatible with
4642 // added qualification. But that wasn't the case, so the reference
4643 // initialization fails.
4644 //
4645 // Note that we only want to check address spaces and cvr-qualifiers here.
4646 // ObjC GC, lifetime and unaligned qualifiers aren't important.
4647 Qualifiers T1Quals = T1.getQualifiers();
4648 Qualifiers T2Quals = T2.getQualifiers();
4649 T1Quals.removeObjCGCAttr();
4650 T1Quals.removeObjCLifetime();
4651 T2Quals.removeObjCGCAttr();
4652 T2Quals.removeObjCLifetime();
4653 // MS compiler ignores __unaligned qualifier for references; do the same.
4654 T1Quals.removeUnaligned();
4655 T2Quals.removeUnaligned();
4656 if (!T1Quals.compatiblyIncludes(T2Quals))
4657 return ICS;
4658 }
4659
4660 // If at least one of the types is a class type, the types are not
4661 // related, and we aren't allowed any user conversions, the
4662 // reference binding fails. This case is important for breaking
4663 // recursion, since TryImplicitConversion below will attempt to
4664 // create a temporary through the use of a copy constructor.
4665 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible &&
4666 (T1->isRecordType() || T2->isRecordType()))
4667 return ICS;
4668
4669 // If T1 is reference-related to T2 and the reference is an rvalue
4670 // reference, the initializer expression shall not be an lvalue.
4671 if (RefRelationship >= Sema::Ref_Related &&
4672 isRValRef && Init->Classify(S.Context).isLValue())
4673 return ICS;
4674
4675 // C++ [over.ics.ref]p2:
4676 // When a parameter of reference type is not bound directly to
4677 // an argument expression, the conversion sequence is the one
4678 // required to convert the argument expression to the
4679 // underlying type of the reference according to
4680 // 13.3.3.1. Conceptually, this conversion sequence corresponds
4681 // to copy-initializing a temporary of the underlying type with
4682 // the argument expression. Any difference in top-level
4683 // cv-qualification is subsumed by the initialization itself
4684 // and does not constitute a conversion.
4685 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions,
4686 /*AllowExplicit=*/false,
4687 /*InOverloadResolution=*/false,
4688 /*CStyle=*/false,
4689 /*AllowObjCWritebackConversion=*/false,
4690 /*AllowObjCConversionOnExplicit=*/false);
4691
4692 // Of course, that's still a reference binding.
4693 if (ICS.isStandard()) {
4694 ICS.Standard.ReferenceBinding = true;
4695 ICS.Standard.IsLvalueReference = !isRValRef;
4696 ICS.Standard.BindsToFunctionLvalue = false;
4697 ICS.Standard.BindsToRvalue = true;
4698 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4699 ICS.Standard.ObjCLifetimeConversionBinding = false;
4700 } else if (ICS.isUserDefined()) {
4701 const ReferenceType *LValRefType =
4702 ICS.UserDefined.ConversionFunction->getReturnType()
4703 ->getAs<LValueReferenceType>();
4704
4705 // C++ [over.ics.ref]p3:
4706 // Except for an implicit object parameter, for which see 13.3.1, a
4707 // standard conversion sequence cannot be formed if it requires [...]
4708 // binding an rvalue reference to an lvalue other than a function
4709 // lvalue.
4710 // Note that the function case is not possible here.
4711 if (DeclType->isRValueReferenceType() && LValRefType) {
4712 // FIXME: This is the wrong BadConversionSequence. The problem is binding
4713 // an rvalue reference to a (non-function) lvalue, not binding an lvalue
4714 // reference to an rvalue!
4715 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, Init, DeclType);
4716 return ICS;
4717 }
4718
4719 ICS.UserDefined.After.ReferenceBinding = true;
4720 ICS.UserDefined.After.IsLvalueReference = !isRValRef;
4721 ICS.UserDefined.After.BindsToFunctionLvalue = false;
4722 ICS.UserDefined.After.BindsToRvalue = !LValRefType;
4723 ICS.UserDefined.After.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4724 ICS.UserDefined.After.ObjCLifetimeConversionBinding = false;
4725 }
4726
4727 return ICS;
4728}
4729
4730static ImplicitConversionSequence
4731TryCopyInitialization(Sema &S, Expr *From, QualType ToType,
4732 bool SuppressUserConversions,
4733 bool InOverloadResolution,
4734 bool AllowObjCWritebackConversion,
4735 bool AllowExplicit = false);
4736
4737/// TryListConversion - Try to copy-initialize a value of type ToType from the
4738/// initializer list From.
4739static ImplicitConversionSequence
4740TryListConversion(Sema &S, InitListExpr *From, QualType ToType,
4741 bool SuppressUserConversions,
4742 bool InOverloadResolution,
4743 bool AllowObjCWritebackConversion) {
4744 // C++11 [over.ics.list]p1:
4745 // When an argument is an initializer list, it is not an expression and
4746 // special rules apply for converting it to a parameter type.
4747
4748 ImplicitConversionSequence Result;
4749 Result.setBad(BadConversionSequence::no_conversion, From, ToType);
4750
4751 // We need a complete type for what follows. Incomplete types can never be
4752 // initialized from init lists.
4753 if (!S.isCompleteType(From->getBeginLoc(), ToType))
4754 return Result;
4755
4756 // Per DR1467:
4757 // If the parameter type is a class X and the initializer list has a single
4758 // element of type cv U, where U is X or a class derived from X, the
4759 // implicit conversion sequence is the one required to convert the element
4760 // to the parameter type.
4761 //
4762 // Otherwise, if the parameter type is a character array [... ]
4763 // and the initializer list has a single element that is an
4764 // appropriately-typed string literal (8.5.2 [dcl.init.string]), the
4765 // implicit conversion sequence is the identity conversion.
4766 if (From->getNumInits() == 1) {
4767 if (ToType->isRecordType()) {
4768 QualType InitType = From->getInit(0)->getType();
4769 if (S.Context.hasSameUnqualifiedType(InitType, ToType) ||
4770 S.IsDerivedFrom(From->getBeginLoc(), InitType, ToType))
4771 return TryCopyInitialization(S, From->getInit(0), ToType,
4772 SuppressUserConversions,
4773 InOverloadResolution,
4774 AllowObjCWritebackConversion);
4775 }
4776 // FIXME: Check the other conditions here: array of character type,
4777 // initializer is a string literal.
4778 if (ToType->isArrayType()) {
4779 InitializedEntity Entity =
4780 InitializedEntity::InitializeParameter(S.Context, ToType,
4781 /*Consumed=*/false);
4782 if (S.CanPerformCopyInitialization(Entity, From)) {
4783 Result.setStandard();
4784 Result.Standard.setAsIdentityConversion();
4785 Result.Standard.setFromType(ToType);
4786 Result.Standard.setAllToTypes(ToType);
4787 return Result;
4788 }
4789 }
4790 }
4791
4792 // C++14 [over.ics.list]p2: Otherwise, if the parameter type [...] (below).
4793 // C++11 [over.ics.list]p2:
4794 // If the parameter type is std::initializer_list<X> or "array of X" and
4795 // all the elements can be implicitly converted to X, the implicit
4796 // conversion sequence is the worst conversion necessary to convert an
4797 // element of the list to X.
4798 //
4799 // C++14 [over.ics.list]p3:
4800 // Otherwise, if the parameter type is "array of N X", if the initializer
4801 // list has exactly N elements or if it has fewer than N elements and X is
4802 // default-constructible, and if all the elements of the initializer list
4803 // can be implicitly converted to X, the implicit conversion sequence is
4804 // the worst conversion necessary to convert an element of the list to X.
4805 //
4806 // FIXME: We're missing a lot of these checks.
4807 bool toStdInitializerList = false;
4808 QualType X;
4809 if (ToType->isArrayType())
4810 X = S.Context.getAsArrayType(ToType)->getElementType();
4811 else
4812 toStdInitializerList = S.isStdInitializerList(ToType, &X);
4813 if (!X.isNull()) {
4814 for (unsigned i = 0, e = From->getNumInits(); i < e; ++i) {
4815 Expr *Init = From->getInit(i);
4816 ImplicitConversionSequence ICS =
4817 TryCopyInitialization(S, Init, X, SuppressUserConversions,
4818 InOverloadResolution,
4819 AllowObjCWritebackConversion);
4820 // If a single element isn't convertible, fail.
4821 if (ICS.isBad()) {
4822 Result = ICS;
4823 break;
4824 }
4825 // Otherwise, look for the worst conversion.
4826 if (Result.isBad() || CompareImplicitConversionSequences(
4827 S, From->getBeginLoc(), ICS, Result) ==
4828 ImplicitConversionSequence::Worse)
4829 Result = ICS;
4830 }
4831
4832 // For an empty list, we won't have computed any conversion sequence.
4833 // Introduce the identity conversion sequence.
4834 if (From->getNumInits() == 0) {
4835 Result.setStandard();
4836 Result.Standard.setAsIdentityConversion();
4837 Result.Standard.setFromType(ToType);
4838 Result.Standard.setAllToTypes(ToType);
4839 }
4840
4841 Result.setStdInitializerListElement(toStdInitializerList);
4842 return Result;
4843 }
4844
4845 // C++14 [over.ics.list]p4:
4846 // C++11 [over.ics.list]p3:
4847 // Otherwise, if the parameter is a non-aggregate class X and overload
4848 // resolution chooses a single best constructor [...] the implicit
4849 // conversion sequence is a user-defined conversion sequence. If multiple
4850 // constructors are viable but none is better than the others, the
4851 // implicit conversion sequence is a user-defined conversion sequence.
4852 if (ToType->isRecordType() && !ToType->isAggregateType()) {
4853 // This function can deal with initializer lists.
4854 return TryUserDefinedConversion(S, From, ToType, SuppressUserConversions,
4855 /*AllowExplicit=*/false,
4856 InOverloadResolution, /*CStyle=*/false,
4857 AllowObjCWritebackConversion,
4858 /*AllowObjCConversionOnExplicit=*/false);
4859 }
4860
4861 // C++14 [over.ics.list]p5:
4862 // C++11 [over.ics.list]p4:
4863 // Otherwise, if the parameter has an aggregate type which can be
4864 // initialized from the initializer list [...] the implicit conversion
4865 // sequence is a user-defined conversion sequence.
4866 if (ToType->isAggregateType()) {
4867 // Type is an aggregate, argument is an init list. At this point it comes
4868 // down to checking whether the initialization works.
4869 // FIXME: Find out whether this parameter is consumed or not.
4870 // FIXME: Expose SemaInit's aggregate initialization code so that we don't
4871 // need to call into the initialization code here; overload resolution
4872 // should not be doing that.
4873 InitializedEntity Entity =
4874 InitializedEntity::InitializeParameter(S.Context, ToType,
4875 /*Consumed=*/false);
4876 if (S.CanPerformCopyInitialization(Entity, From)) {
4877 Result.setUserDefined();
4878 Result.UserDefined.Before.setAsIdentityConversion();
4879 // Initializer lists don't have a type.
4880 Result.UserDefined.Before.setFromType(QualType());
4881 Result.UserDefined.Before.setAllToTypes(QualType());
4882
4883 Result.UserDefined.After.setAsIdentityConversion();
4884 Result.UserDefined.After.setFromType(ToType);
4885 Result.UserDefined.After.setAllToTypes(ToType);
4886 Result.UserDefined.ConversionFunction = nullptr;
4887 }
4888 return Result;
4889 }
4890
4891 // C++14 [over.ics.list]p6:
4892 // C++11 [over.ics.list]p5:
4893 // Otherwise, if the parameter is a reference, see 13.3.3.1.4.
4894 if (ToType->isReferenceType()) {
4895 // The standard is notoriously unclear here, since 13.3.3.1.4 doesn't
4896 // mention initializer lists in any way. So we go by what list-
4897 // initialization would do and try to extrapolate from that.
4898
4899 QualType T1 = ToType->getAs<ReferenceType>()->getPointeeType();
4900
4901 // If the initializer list has a single element that is reference-related
4902 // to the parameter type, we initialize the reference from that.
4903 if (From->getNumInits() == 1) {
4904 Expr *Init = From->getInit(0);
4905
4906 QualType T2 = Init->getType();
4907
4908 // If the initializer is the address of an overloaded function, try
4909 // to resolve the overloaded function. If all goes well, T2 is the
4910 // type of the resulting function.
4911 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) {
4912 DeclAccessPair Found;
4913 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(
4914 Init, ToType, false, Found))
4915 T2 = Fn->getType();
4916 }
4917
4918 // Compute some basic properties of the types and the initializer.
4919 bool dummy1 = false;
4920 bool dummy2 = false;
4921 bool dummy3 = false;
4922 Sema::ReferenceCompareResult RefRelationship =
4923 S.CompareReferenceRelationship(From->getBeginLoc(), T1, T2, dummy1,
4924 dummy2, dummy3);
4925
4926 if (RefRelationship >= Sema::Ref_Related) {
4927 return TryReferenceInit(S, Init, ToType, /*FIXME*/ From->getBeginLoc(),
4928 SuppressUserConversions,
4929 /*AllowExplicit=*/false);
4930 }
4931 }
4932
4933 // Otherwise, we bind the reference to a temporary created from the
4934 // initializer list.
4935 Result = TryListConversion(S, From, T1, SuppressUserConversions,
4936 InOverloadResolution,
4937 AllowObjCWritebackConversion);
4938 if (Result.isFailure())
4939 return Result;
4940 assert(!Result.isEllipsis() &&((!Result.isEllipsis() && "Sub-initialization cannot result in ellipsis conversion."
) ? static_cast<void> (0) : __assert_fail ("!Result.isEllipsis() && \"Sub-initialization cannot result in ellipsis conversion.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4941, __PRETTY_FUNCTION__))
4941 "Sub-initialization cannot result in ellipsis conversion.")((!Result.isEllipsis() && "Sub-initialization cannot result in ellipsis conversion."
) ? static_cast<void> (0) : __assert_fail ("!Result.isEllipsis() && \"Sub-initialization cannot result in ellipsis conversion.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 4941, __PRETTY_FUNCTION__))
;
4942
4943 // Can we even bind to a temporary?
4944 if (ToType->isRValueReferenceType() ||
4945 (T1.isConstQualified() && !T1.isVolatileQualified())) {
4946 StandardConversionSequence &SCS = Result.isStandard() ? Result.Standard :
4947 Result.UserDefined.After;
4948 SCS.ReferenceBinding = true;
4949 SCS.IsLvalueReference = ToType->isLValueReferenceType();
4950 SCS.BindsToRvalue = true;
4951 SCS.BindsToFunctionLvalue = false;
4952 SCS.BindsImplicitObjectArgumentWithoutRefQualifier = false;
4953 SCS.ObjCLifetimeConversionBinding = false;
4954 } else
4955 Result.setBad(BadConversionSequence::lvalue_ref_to_rvalue,
4956 From, ToType);
4957 return Result;
4958 }
4959
4960 // C++14 [over.ics.list]p7:
4961 // C++11 [over.ics.list]p6:
4962 // Otherwise, if the parameter type is not a class:
4963 if (!ToType->isRecordType()) {
4964 // - if the initializer list has one element that is not itself an
4965 // initializer list, the implicit conversion sequence is the one
4966 // required to convert the element to the parameter type.
4967 unsigned NumInits = From->getNumInits();
4968 if (NumInits == 1 && !isa<InitListExpr>(From->getInit(0)))
4969 Result = TryCopyInitialization(S, From->getInit(0), ToType,
4970 SuppressUserConversions,
4971 InOverloadResolution,
4972 AllowObjCWritebackConversion);
4973 // - if the initializer list has no elements, the implicit conversion
4974 // sequence is the identity conversion.
4975 else if (NumInits == 0) {
4976 Result.setStandard();
4977 Result.Standard.setAsIdentityConversion();
4978 Result.Standard.setFromType(ToType);
4979 Result.Standard.setAllToTypes(ToType);
4980 }
4981 return Result;
4982 }
4983
4984 // C++14 [over.ics.list]p8:
4985 // C++11 [over.ics.list]p7:
4986 // In all cases other than those enumerated above, no conversion is possible
4987 return Result;
4988}
4989
4990/// TryCopyInitialization - Try to copy-initialize a value of type
4991/// ToType from the expression From. Return the implicit conversion
4992/// sequence required to pass this argument, which may be a bad
4993/// conversion sequence (meaning that the argument cannot be passed to
4994/// a parameter of this type). If @p SuppressUserConversions, then we
4995/// do not permit any user-defined conversion sequences.
4996static ImplicitConversionSequence
4997TryCopyInitialization(Sema &S, Expr *From, QualType ToType,
4998 bool SuppressUserConversions,
4999 bool InOverloadResolution,
5000 bool AllowObjCWritebackConversion,
5001 bool AllowExplicit) {
5002 if (InitListExpr *FromInitList = dyn_cast<InitListExpr>(From))
5003 return TryListConversion(S, FromInitList, ToType, SuppressUserConversions,
5004 InOverloadResolution,AllowObjCWritebackConversion);
5005
5006 if (ToType->isReferenceType())
5007 return TryReferenceInit(S, From, ToType,
5008 /*FIXME:*/ From->getBeginLoc(),
5009 SuppressUserConversions, AllowExplicit);
5010
5011 return TryImplicitConversion(S, From, ToType,
5012 SuppressUserConversions,
5013 /*AllowExplicit=*/false,
5014 InOverloadResolution,
5015 /*CStyle=*/false,
5016 AllowObjCWritebackConversion,
5017 /*AllowObjCConversionOnExplicit=*/false);
5018}
5019
5020static bool TryCopyInitialization(const CanQualType FromQTy,
5021 const CanQualType ToQTy,
5022 Sema &S,
5023 SourceLocation Loc,
5024 ExprValueKind FromVK) {
5025 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK);
5026 ImplicitConversionSequence ICS =
5027 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false);
5028
5029 return !ICS.isBad();
5030}
5031
5032/// TryObjectArgumentInitialization - Try to initialize the object
5033/// parameter of the given member function (@c Method) from the
5034/// expression @p From.
5035static ImplicitConversionSequence
5036TryObjectArgumentInitialization(Sema &S, SourceLocation Loc, QualType FromType,
5037 Expr::Classification FromClassification,
5038 CXXMethodDecl *Method,
5039 CXXRecordDecl *ActingContext) {
5040 QualType ClassType = S.Context.getTypeDeclType(ActingContext);
5041 // [class.dtor]p2: A destructor can be invoked for a const, volatile or
5042 // const volatile object.
5043 unsigned Quals = isa<CXXDestructorDecl>(Method) ?
5044 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers();
5045 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals);
5046
5047 // Set up the conversion sequence as a "bad" conversion, to allow us
5048 // to exit early.
5049 ImplicitConversionSequence ICS;
5050
5051 // We need to have an object of class type.
5052 if (const PointerType *PT = FromType->getAs<PointerType>()) {
5053 FromType = PT->getPointeeType();
5054
5055 // When we had a pointer, it's implicitly dereferenced, so we
5056 // better have an lvalue.
5057 assert(FromClassification.isLValue())((FromClassification.isLValue()) ? static_cast<void> (0
) : __assert_fail ("FromClassification.isLValue()", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5057, __PRETTY_FUNCTION__))
;
5058 }
5059
5060 assert(FromType->isRecordType())((FromType->isRecordType()) ? static_cast<void> (0) :
__assert_fail ("FromType->isRecordType()", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5060, __PRETTY_FUNCTION__))
;
5061
5062 // C++0x [over.match.funcs]p4:
5063 // For non-static member functions, the type of the implicit object
5064 // parameter is
5065 //
5066 // - "lvalue reference to cv X" for functions declared without a
5067 // ref-qualifier or with the & ref-qualifier
5068 // - "rvalue reference to cv X" for functions declared with the &&
5069 // ref-qualifier
5070 //
5071 // where X is the class of which the function is a member and cv is the
5072 // cv-qualification on the member function declaration.
5073 //
5074 // However, when finding an implicit conversion sequence for the argument, we
5075 // are not allowed to perform user-defined conversions
5076 // (C++ [over.match.funcs]p5). We perform a simplified version of
5077 // reference binding here, that allows class rvalues to bind to
5078 // non-constant references.
5079
5080 // First check the qualifiers.
5081 QualType FromTypeCanon = S.Context.getCanonicalType(FromType);
5082 if (ImplicitParamType.getCVRQualifiers()
5083 != FromTypeCanon.getLocalCVRQualifiers() &&
5084 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) {
5085 ICS.setBad(BadConversionSequence::bad_qualifiers,
5086 FromType, ImplicitParamType);
5087 return ICS;
5088 }
5089
5090 // Check that we have either the same type or a derived type. It
5091 // affects the conversion rank.
5092 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType);
5093 ImplicitConversionKind SecondKind;
5094 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) {
5095 SecondKind = ICK_Identity;
5096 } else if (S.IsDerivedFrom(Loc, FromType, ClassType))
5097 SecondKind = ICK_Derived_To_Base;
5098 else {
5099 ICS.setBad(BadConversionSequence::unrelated_class,
5100 FromType, ImplicitParamType);
5101 return ICS;
5102 }
5103
5104 // Check the ref-qualifier.
5105 switch (Method->getRefQualifier()) {
5106 case RQ_None:
5107 // Do nothing; we don't care about lvalueness or rvalueness.
5108 break;
5109
5110 case RQ_LValue:
5111 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) {
5112 // non-const lvalue reference cannot bind to an rvalue
5113 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType,
5114 ImplicitParamType);
5115 return ICS;
5116 }
5117 break;
5118
5119 case RQ_RValue:
5120 if (!FromClassification.isRValue()) {
5121 // rvalue reference cannot bind to an lvalue
5122 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType,
5123 ImplicitParamType);
5124 return ICS;
5125 }
5126 break;
5127 }
5128
5129 // Success. Mark this as a reference binding.
5130 ICS.setStandard();
5131 ICS.Standard.setAsIdentityConversion();
5132 ICS.Standard.Second = SecondKind;
5133 ICS.Standard.setFromType(FromType);
5134 ICS.Standard.setAllToTypes(ImplicitParamType);
5135 ICS.Standard.ReferenceBinding = true;
5136 ICS.Standard.DirectBinding = true;
5137 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue;
5138 ICS.Standard.BindsToFunctionLvalue = false;
5139 ICS.Standard.BindsToRvalue = FromClassification.isRValue();
5140 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier
5141 = (Method->getRefQualifier() == RQ_None);
5142 return ICS;
5143}
5144
5145/// PerformObjectArgumentInitialization - Perform initialization of
5146/// the implicit object parameter for the given Method with the given
5147/// expression.
5148ExprResult
5149Sema::PerformObjectArgumentInitialization(Expr *From,
5150 NestedNameSpecifier *Qualifier,
5151 NamedDecl *FoundDecl,
5152 CXXMethodDecl *Method) {
5153 QualType FromRecordType, DestType;
5154 QualType ImplicitParamRecordType =
5155 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType();
5156
5157 Expr::Classification FromClassification;
5158 if (const PointerType *PT = From->getType()->getAs<PointerType>()) {
5159 FromRecordType = PT->getPointeeType();
5160 DestType = Method->getThisType(Context);
5161 FromClassification = Expr::Classification::makeSimpleLValue();
5162 } else {
5163 FromRecordType = From->getType();
5164 DestType = ImplicitParamRecordType;
5165 FromClassification = From->Classify(Context);
5166
5167 // When performing member access on an rvalue, materialize a temporary.
5168 if (From->isRValue()) {
5169 From = CreateMaterializeTemporaryExpr(FromRecordType, From,
5170 Method->getRefQualifier() !=
5171 RefQualifierKind::RQ_RValue);
5172 }
5173 }
5174
5175 // Note that we always use the true parent context when performing
5176 // the actual argument initialization.
5177 ImplicitConversionSequence ICS = TryObjectArgumentInitialization(
5178 *this, From->getBeginLoc(), From->getType(), FromClassification, Method,
5179 Method->getParent());
5180 if (ICS.isBad()) {
5181 switch (ICS.Bad.Kind) {
5182 case BadConversionSequence::bad_qualifiers: {
5183 Qualifiers FromQs = FromRecordType.getQualifiers();
5184 Qualifiers ToQs = DestType.getQualifiers();
5185 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers();
5186 if (CVR) {
5187 Diag(From->getBeginLoc(), diag::err_member_function_call_bad_cvr)
5188 << Method->getDeclName() << FromRecordType << (CVR - 1)
5189 << From->getSourceRange();
5190 Diag(Method->getLocation(), diag::note_previous_decl)
5191 << Method->getDeclName();
5192 return ExprError();
5193 }
5194 break;
5195 }
5196
5197 case BadConversionSequence::lvalue_ref_to_rvalue:
5198 case BadConversionSequence::rvalue_ref_to_lvalue: {
5199 bool IsRValueQualified =
5200 Method->getRefQualifier() == RefQualifierKind::RQ_RValue;
5201 Diag(From->getBeginLoc(), diag::err_member_function_call_bad_ref)
5202 << Method->getDeclName() << FromClassification.isRValue()
5203 << IsRValueQualified;
5204 Diag(Method->getLocation(), diag::note_previous_decl)
5205 << Method->getDeclName();
5206 return ExprError();
5207 }
5208
5209 case BadConversionSequence::no_conversion:
5210 case BadConversionSequence::unrelated_class:
5211 break;
5212 }
5213
5214 return Diag(From->getBeginLoc(), diag::err_member_function_call_bad_type)
5215 << ImplicitParamRecordType << FromRecordType
5216 << From->getSourceRange();
5217 }
5218
5219 if (ICS.Standard.Second == ICK_Derived_To_Base) {
5220 ExprResult FromRes =
5221 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method);
5222 if (FromRes.isInvalid())
5223 return ExprError();
5224 From = FromRes.get();
5225 }
5226
5227 if (!Context.hasSameType(From->getType(), DestType))
5228 From = ImpCastExprToType(From, DestType, CK_NoOp,
5229 From->getValueKind()).get();
5230 return From;
5231}
5232
5233/// TryContextuallyConvertToBool - Attempt to contextually convert the
5234/// expression From to bool (C++0x [conv]p3).
5235static ImplicitConversionSequence
5236TryContextuallyConvertToBool(Sema &S, Expr *From) {
5237 return TryImplicitConversion(S, From, S.Context.BoolTy,
5238 /*SuppressUserConversions=*/false,
5239 /*AllowExplicit=*/true,
5240 /*InOverloadResolution=*/false,
5241 /*CStyle=*/false,
5242 /*AllowObjCWritebackConversion=*/false,
5243 /*AllowObjCConversionOnExplicit=*/false);
5244}
5245
5246/// PerformContextuallyConvertToBool - Perform a contextual conversion
5247/// of the expression From to bool (C++0x [conv]p3).
5248ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) {
5249 if (checkPlaceholderForOverload(*this, From))
5250 return ExprError();
5251
5252 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From);
5253 if (!ICS.isBad())
5254 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting);
5255
5256 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy))
5257 return Diag(From->getBeginLoc(), diag::err_typecheck_bool_condition)
5258 << From->getType() << From->getSourceRange();
5259 return ExprError();
5260}
5261
5262/// Check that the specified conversion is permitted in a converted constant
5263/// expression, according to C++11 [expr.const]p3. Return true if the conversion
5264/// is acceptable.
5265static bool CheckConvertedConstantConversions(Sema &S,
5266 StandardConversionSequence &SCS) {
5267 // Since we know that the target type is an integral or unscoped enumeration
5268 // type, most conversion kinds are impossible. All possible First and Third
5269 // conversions are fine.
5270 switch (SCS.Second) {
5271 case ICK_Identity:
5272 case ICK_Function_Conversion:
5273 case ICK_Integral_Promotion:
5274 case ICK_Integral_Conversion: // Narrowing conversions are checked elsewhere.
5275 case ICK_Zero_Queue_Conversion:
5276 return true;
5277
5278 case ICK_Boolean_Conversion:
5279 // Conversion from an integral or unscoped enumeration type to bool is
5280 // classified as ICK_Boolean_Conversion, but it's also arguably an integral
5281 // conversion, so we allow it in a converted constant expression.
5282 //
5283 // FIXME: Per core issue 1407, we should not allow this, but that breaks
5284 // a lot of popular code. We should at least add a warning for this
5285 // (non-conforming) extension.
5286 return SCS.getFromType()->isIntegralOrUnscopedEnumerationType() &&
5287 SCS.getToType(2)->isBooleanType();
5288
5289 case ICK_Pointer_Conversion:
5290 case ICK_Pointer_Member:
5291 // C++1z: null pointer conversions and null member pointer conversions are
5292 // only permitted if the source type is std::nullptr_t.
5293 return SCS.getFromType()->isNullPtrType();
5294
5295 case ICK_Floating_Promotion:
5296 case ICK_Complex_Promotion:
5297 case ICK_Floating_Conversion:
5298 case ICK_Complex_Conversion:
5299 case ICK_Floating_Integral:
5300 case ICK_Compatible_Conversion:
5301 case ICK_Derived_To_Base:
5302 case ICK_Vector_Conversion:
5303 case ICK_Vector_Splat:
5304 case ICK_Complex_Real:
5305 case ICK_Block_Pointer_Conversion:
5306 case ICK_TransparentUnionConversion:
5307 case ICK_Writeback_Conversion:
5308 case ICK_Zero_Event_Conversion:
5309 case ICK_C_Only_Conversion:
5310 case ICK_Incompatible_Pointer_Conversion:
5311 return false;
5312
5313 case ICK_Lvalue_To_Rvalue:
5314 case ICK_Array_To_Pointer:
5315 case ICK_Function_To_Pointer:
5316 llvm_unreachable("found a first conversion kind in Second")::llvm::llvm_unreachable_internal("found a first conversion kind in Second"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5316)
;
5317
5318 case ICK_Qualification:
5319 llvm_unreachable("found a third conversion kind in Second")::llvm::llvm_unreachable_internal("found a third conversion kind in Second"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5319)
;
5320
5321 case ICK_Num_Conversion_Kinds:
5322 break;
5323 }
5324
5325 llvm_unreachable("unknown conversion kind")::llvm::llvm_unreachable_internal("unknown conversion kind", "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5325)
;
5326}
5327
5328/// CheckConvertedConstantExpression - Check that the expression From is a
5329/// converted constant expression of type T, perform the conversion and produce
5330/// the converted expression, per C++11 [expr.const]p3.
5331static ExprResult CheckConvertedConstantExpression(Sema &S, Expr *From,
5332 QualType T, APValue &Value,
5333 Sema::CCEKind CCE,
5334 bool RequireInt) {
5335 assert(S.getLangOpts().CPlusPlus11 &&((S.getLangOpts().CPlusPlus11 && "converted constant expression outside C++11"
) ? static_cast<void> (0) : __assert_fail ("S.getLangOpts().CPlusPlus11 && \"converted constant expression outside C++11\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5336, __PRETTY_FUNCTION__))
5336 "converted constant expression outside C++11")((S.getLangOpts().CPlusPlus11 && "converted constant expression outside C++11"
) ? static_cast<void> (0) : __assert_fail ("S.getLangOpts().CPlusPlus11 && \"converted constant expression outside C++11\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5336, __PRETTY_FUNCTION__))
;
5337
5338 if (checkPlaceholderForOverload(S, From))
5339 return ExprError();
5340
5341 // C++1z [expr.const]p3:
5342 // A converted constant expression of type T is an expression,
5343 // implicitly converted to type T, where the converted
5344 // expression is a constant expression and the implicit conversion
5345 // sequence contains only [... list of conversions ...].
5346 // C++1z [stmt.if]p2:
5347 // If the if statement is of the form if constexpr, the value of the
5348 // condition shall be a contextually converted constant expression of type
5349 // bool.
5350 ImplicitConversionSequence ICS =
5351 CCE == Sema::CCEK_ConstexprIf
5352 ? TryContextuallyConvertToBool(S, From)
5353 : TryCopyInitialization(S, From, T,
5354 /*SuppressUserConversions=*/false,
5355 /*InOverloadResolution=*/false,
5356 /*AllowObjcWritebackConversion=*/false,
5357 /*AllowExplicit=*/false);
5358 StandardConversionSequence *SCS = nullptr;
5359 switch (ICS.getKind()) {
5360 case ImplicitConversionSequence::StandardConversion:
5361 SCS = &ICS.Standard;
5362 break;
5363 case ImplicitConversionSequence::UserDefinedConversion:
5364 // We are converting to a non-class type, so the Before sequence
5365 // must be trivial.
5366 SCS = &ICS.UserDefined.After;
5367 break;
5368 case ImplicitConversionSequence::AmbiguousConversion:
5369 case ImplicitConversionSequence::BadConversion:
5370 if (!S.DiagnoseMultipleUserDefinedConversion(From, T))
5371 return S.Diag(From->getBeginLoc(),
5372 diag::err_typecheck_converted_constant_expression)
5373 << From->getType() << From->getSourceRange() << T;
5374 return ExprError();
5375
5376 case ImplicitConversionSequence::EllipsisConversion:
5377 llvm_unreachable("ellipsis conversion in converted constant expression")::llvm::llvm_unreachable_internal("ellipsis conversion in converted constant expression"
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5377)
;
5378 }
5379
5380 // Check that we would only use permitted conversions.
5381 if (!CheckConvertedConstantConversions(S, *SCS)) {
5382 return S.Diag(From->getBeginLoc(),
5383 diag::err_typecheck_converted_constant_expression_disallowed)
5384 << From->getType() << From->getSourceRange() << T;
5385 }
5386 // [...] and where the reference binding (if any) binds directly.
5387 if (SCS->ReferenceBinding && !SCS->DirectBinding) {
5388 return S.Diag(From->getBeginLoc(),
5389 diag::err_typecheck_converted_constant_expression_indirect)
5390 << From->getType() << From->getSourceRange() << T;
5391 }
5392
5393 ExprResult Result =
5394 S.PerformImplicitConversion(From, T, ICS, Sema::AA_Converting);
5395 if (Result.isInvalid())
5396 return Result;
5397
5398 // Check for a narrowing implicit conversion.
5399 APValue PreNarrowingValue;
5400 QualType PreNarrowingType;
5401 switch (SCS->getNarrowingKind(S.Context, Result.get(), PreNarrowingValue,
5402 PreNarrowingType)) {
5403 case NK_Dependent_Narrowing:
5404 // Implicit conversion to a narrower type, but the expression is
5405 // value-dependent so we can't tell whether it's actually narrowing.
5406 case NK_Variable_Narrowing:
5407 // Implicit conversion to a narrower type, and the value is not a constant
5408 // expression. We'll diagnose this in a moment.
5409 case NK_Not_Narrowing:
5410 break;
5411
5412 case NK_Constant_Narrowing:
5413 S.Diag(From->getBeginLoc(), diag::ext_cce_narrowing)
5414 << CCE << /*Constant*/ 1
5415 << PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << T;
5416 break;
5417
5418 case NK_Type_Narrowing:
5419 S.Diag(From->getBeginLoc(), diag::ext_cce_narrowing)
5420 << CCE << /*Constant*/ 0 << From->getType() << T;
5421 break;
5422 }
5423
5424 if (Result.get()->isValueDependent()) {
5425 Value = APValue();
5426 return Result;
5427 }
5428
5429 // Check the expression is a constant expression.
5430 SmallVector<PartialDiagnosticAt, 8> Notes;
5431 Expr::EvalResult Eval;
5432 Eval.Diag = &Notes;
5433 Expr::ConstExprUsage Usage = CCE == Sema::CCEK_TemplateArg
5434 ? Expr::EvaluateForMangling
5435 : Expr::EvaluateForCodeGen;
5436
5437 if (!Result.get()->EvaluateAsConstantExpr(Eval, Usage, S.Context) ||
5438 (RequireInt && !Eval.Val.isInt())) {
5439 // The expression can't be folded, so we can't keep it at this position in
5440 // the AST.
5441 Result = ExprError();
5442 } else {
5443 Value = Eval.Val;
5444
5445 if (Notes.empty()) {
5446 // It's a constant expression.
5447 return Result;
5448 }
5449 }
5450
5451 // It's not a constant expression. Produce an appropriate diagnostic.
5452 if (Notes.size() == 1 &&
5453 Notes[0].second.getDiagID() == diag::note_invalid_subexpr_in_const_expr)
5454 S.Diag(Notes[0].first, diag::err_expr_not_cce) << CCE;
5455 else {
5456 S.Diag(From->getBeginLoc(), diag::err_expr_not_cce)
5457 << CCE << From->getSourceRange();
5458 for (unsigned I = 0; I < Notes.size(); ++I)
5459 S.Diag(Notes[I].first, Notes[I].second);
5460 }
5461 return ExprError();
5462}
5463
5464ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
5465 APValue &Value, CCEKind CCE) {
5466 return ::CheckConvertedConstantExpression(*this, From, T, Value, CCE, false);
5467}
5468
5469ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T,
5470 llvm::APSInt &Value,
5471 CCEKind CCE) {
5472 assert(T->isIntegralOrEnumerationType() && "unexpected converted const type")((T->isIntegralOrEnumerationType() && "unexpected converted const type"
) ? static_cast<void> (0) : __assert_fail ("T->isIntegralOrEnumerationType() && \"unexpected converted const type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5472, __PRETTY_FUNCTION__))
;
5473
5474 APValue V;
5475 auto R = ::CheckConvertedConstantExpression(*this, From, T, V, CCE, true);
5476 if (!R.isInvalid() && !R.get()->isValueDependent())
5477 Value = V.getInt();
5478 return R;
5479}
5480
5481
5482/// dropPointerConversions - If the given standard conversion sequence
5483/// involves any pointer conversions, remove them. This may change
5484/// the result type of the conversion sequence.
5485static void dropPointerConversion(StandardConversionSequence &SCS) {
5486 if (SCS.Second == ICK_Pointer_Conversion) {
5487 SCS.Second = ICK_Identity;
5488 SCS.Third = ICK_Identity;
5489 SCS.ToTypePtrs[2] = SCS.ToTypePtrs[1] = SCS.ToTypePtrs[0];
5490 }
5491}
5492
5493/// TryContextuallyConvertToObjCPointer - Attempt to contextually
5494/// convert the expression From to an Objective-C pointer type.
5495static ImplicitConversionSequence
5496TryContextuallyConvertToObjCPointer(Sema &S, Expr *From) {
5497 // Do an implicit conversion to 'id'.
5498 QualType Ty = S.Context.getObjCIdType();
5499 ImplicitConversionSequence ICS
5500 = TryImplicitConversion(S, From, Ty,
5501 // FIXME: Are these flags correct?
5502 /*SuppressUserConversions=*/false,
5503 /*AllowExplicit=*/true,
5504 /*InOverloadResolution=*/false,
5505 /*CStyle=*/false,
5506 /*AllowObjCWritebackConversion=*/false,
5507 /*AllowObjCConversionOnExplicit=*/true);
5508
5509 // Strip off any final conversions to 'id'.
5510 switch (ICS.getKind()) {
5511 case ImplicitConversionSequence::BadConversion:
5512 case ImplicitConversionSequence::AmbiguousConversion:
5513 case ImplicitConversionSequence::EllipsisConversion:
5514 break;
5515
5516 case ImplicitConversionSequence::UserDefinedConversion:
5517 dropPointerConversion(ICS.UserDefined.After);
5518 break;
5519
5520 case ImplicitConversionSequence::StandardConversion:
5521 dropPointerConversion(ICS.Standard);
5522 break;
5523 }
5524
5525 return ICS;
5526}
5527
5528/// PerformContextuallyConvertToObjCPointer - Perform a contextual
5529/// conversion of the expression From to an Objective-C pointer type.
5530/// Returns a valid but null ExprResult if no conversion sequence exists.
5531ExprResult Sema::PerformContextuallyConvertToObjCPointer(Expr *From) {
5532 if (checkPlaceholderForOverload(*this, From))
5533 return ExprError();
5534
5535 QualType Ty = Context.getObjCIdType();
5536 ImplicitConversionSequence ICS =
5537 TryContextuallyConvertToObjCPointer(*this, From);
5538 if (!ICS.isBad())
5539 return PerformImplicitConversion(From, Ty, ICS, AA_Converting);
5540 return ExprResult();
5541}
5542
5543/// Determine whether the provided type is an integral type, or an enumeration
5544/// type of a permitted flavor.
5545bool Sema::ICEConvertDiagnoser::match(QualType T) {
5546 return AllowScopedEnumerations ? T->isIntegralOrEnumerationType()
5547 : T->isIntegralOrUnscopedEnumerationType();
5548}
5549
5550static ExprResult
5551diagnoseAmbiguousConversion(Sema &SemaRef, SourceLocation Loc, Expr *From,
5552 Sema::ContextualImplicitConverter &Converter,
5553 QualType T, UnresolvedSetImpl &ViableConversions) {
5554
5555 if (Converter.Suppress)
5556 return ExprError();
5557
5558 Converter.diagnoseAmbiguous(SemaRef, Loc, T) << From->getSourceRange();
5559 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
5560 CXXConversionDecl *Conv =
5561 cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl());
5562 QualType ConvTy = Conv->getConversionType().getNonReferenceType();
5563 Converter.noteAmbiguous(SemaRef, Conv, ConvTy);
5564 }
5565 return From;
5566}
5567
5568static bool
5569diagnoseNoViableConversion(Sema &SemaRef, SourceLocation Loc, Expr *&From,
5570 Sema::ContextualImplicitConverter &Converter,
5571 QualType T, bool HadMultipleCandidates,
5572 UnresolvedSetImpl &ExplicitConversions) {
5573 if (ExplicitConversions.size() == 1 && !Converter.Suppress) {
5574 DeclAccessPair Found = ExplicitConversions[0];
5575 CXXConversionDecl *Conversion =
5576 cast<CXXConversionDecl>(Found->getUnderlyingDecl());
5577
5578 // The user probably meant to invoke the given explicit
5579 // conversion; use it.
5580 QualType ConvTy = Conversion->getConversionType().getNonReferenceType();
5581 std::string TypeStr;
5582 ConvTy.getAsStringInternal(TypeStr, SemaRef.getPrintingPolicy());
5583
5584 Converter.diagnoseExplicitConv(SemaRef, Loc, T, ConvTy)
5585 << FixItHint::CreateInsertion(From->getBeginLoc(),
5586 "static_cast<" + TypeStr + ">(")
5587 << FixItHint::CreateInsertion(
5588 SemaRef.getLocForEndOfToken(From->getEndLoc()), ")");
5589 Converter.noteExplicitConv(SemaRef, Conversion, ConvTy);
5590
5591 // If we aren't in a SFINAE context, build a call to the
5592 // explicit conversion function.
5593 if (SemaRef.isSFINAEContext())
5594 return true;
5595
5596 SemaRef.CheckMemberOperatorAccess(From->getExprLoc(), From, nullptr, Found);
5597 ExprResult Result = SemaRef.BuildCXXMemberCallExpr(From, Found, Conversion,
5598 HadMultipleCandidates);
5599 if (Result.isInvalid())
5600 return true;
5601 // Record usage of conversion in an implicit cast.
5602 From = ImplicitCastExpr::Create(SemaRef.Context, Result.get()->getType(),
5603 CK_UserDefinedConversion, Result.get(),
5604 nullptr, Result.get()->getValueKind());
5605 }
5606 return false;
5607}
5608
5609static bool recordConversion(Sema &SemaRef, SourceLocation Loc, Expr *&From,
5610 Sema::ContextualImplicitConverter &Converter,
5611 QualType T, bool HadMultipleCandidates,
5612 DeclAccessPair &Found) {
5613 CXXConversionDecl *Conversion =
5614 cast<CXXConversionDecl>(Found->getUnderlyingDecl());
5615 SemaRef.CheckMemberOperatorAccess(From->getExprLoc(), From, nullptr, Found);
5616
5617 QualType ToType = Conversion->getConversionType().getNonReferenceType();
5618 if (!Converter.SuppressConversion) {
5619 if (SemaRef.isSFINAEContext())
5620 return true;
5621
5622 Converter.diagnoseConversion(SemaRef, Loc, T, ToType)
5623 << From->getSourceRange();
5624 }
5625
5626 ExprResult Result = SemaRef.BuildCXXMemberCallExpr(From, Found, Conversion,
5627 HadMultipleCandidates);
5628 if (Result.isInvalid())
5629 return true;
5630 // Record usage of conversion in an implicit cast.
5631 From = ImplicitCastExpr::Create(SemaRef.Context, Result.get()->getType(),
5632 CK_UserDefinedConversion, Result.get(),
5633 nullptr, Result.get()->getValueKind());
5634 return false;
5635}
5636
5637static ExprResult finishContextualImplicitConversion(
5638 Sema &SemaRef, SourceLocation Loc, Expr *From,
5639 Sema::ContextualImplicitConverter &Converter) {
5640 if (!Converter.match(From->getType()) && !Converter.Suppress)
5641 Converter.diagnoseNoMatch(SemaRef, Loc, From->getType())
5642 << From->getSourceRange();
5643
5644 return SemaRef.DefaultLvalueConversion(From);
5645}
5646
5647static void
5648collectViableConversionCandidates(Sema &SemaRef, Expr *From, QualType ToType,
5649 UnresolvedSetImpl &ViableConversions,
5650 OverloadCandidateSet &CandidateSet) {
5651 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
5652 DeclAccessPair FoundDecl = ViableConversions[I];
5653 NamedDecl *D = FoundDecl.getDecl();
5654 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext());
5655 if (isa<UsingShadowDecl>(D))
5656 D = cast<UsingShadowDecl>(D)->getTargetDecl();
5657
5658 CXXConversionDecl *Conv;
5659 FunctionTemplateDecl *ConvTemplate;
5660 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D)))
5661 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5662 else
5663 Conv = cast<CXXConversionDecl>(D);
5664
5665 if (ConvTemplate)
5666 SemaRef.AddTemplateConversionCandidate(
5667 ConvTemplate, FoundDecl, ActingContext, From, ToType, CandidateSet,
5668 /*AllowObjCConversionOnExplicit=*/false);
5669 else
5670 SemaRef.AddConversionCandidate(Conv, FoundDecl, ActingContext, From,
5671 ToType, CandidateSet,
5672 /*AllowObjCConversionOnExplicit=*/false);
5673 }
5674}
5675
5676/// Attempt to convert the given expression to a type which is accepted
5677/// by the given converter.
5678///
5679/// This routine will attempt to convert an expression of class type to a
5680/// type accepted by the specified converter. In C++11 and before, the class
5681/// must have a single non-explicit conversion function converting to a matching
5682/// type. In C++1y, there can be multiple such conversion functions, but only
5683/// one target type.
5684///
5685/// \param Loc The source location of the construct that requires the
5686/// conversion.
5687///
5688/// \param From The expression we're converting from.
5689///
5690/// \param Converter Used to control and diagnose the conversion process.
5691///
5692/// \returns The expression, converted to an integral or enumeration type if
5693/// successful.
5694ExprResult Sema::PerformContextualImplicitConversion(
5695 SourceLocation Loc, Expr *From, ContextualImplicitConverter &Converter) {
5696 // We can't perform any more checking for type-dependent expressions.
5697 if (From->isTypeDependent())
5698 return From;
5699
5700 // Process placeholders immediately.
5701 if (From->hasPlaceholderType()) {
5702 ExprResult result = CheckPlaceholderExpr(From);
5703 if (result.isInvalid())
5704 return result;
5705 From = result.get();
5706 }
5707
5708 // If the expression already has a matching type, we're golden.
5709 QualType T = From->getType();
5710 if (Converter.match(T))
5711 return DefaultLvalueConversion(From);
5712
5713 // FIXME: Check for missing '()' if T is a function type?
5714
5715 // We can only perform contextual implicit conversions on objects of class
5716 // type.
5717 const RecordType *RecordTy = T->getAs<RecordType>();
5718 if (!RecordTy || !getLangOpts().CPlusPlus) {
5719 if (!Converter.Suppress)
5720 Converter.diagnoseNoMatch(*this, Loc, T) << From->getSourceRange();
5721 return From;
5722 }
5723
5724 // We must have a complete class type.
5725 struct TypeDiagnoserPartialDiag : TypeDiagnoser {
5726 ContextualImplicitConverter &Converter;
5727 Expr *From;
5728
5729 TypeDiagnoserPartialDiag(ContextualImplicitConverter &Converter, Expr *From)
5730 : Converter(Converter), From(From) {}
5731
5732 void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
5733 Converter.diagnoseIncomplete(S, Loc, T) << From->getSourceRange();
5734 }
5735 } IncompleteDiagnoser(Converter, From);
5736
5737 if (Converter.Suppress ? !isCompleteType(Loc, T)
5738 : RequireCompleteType(Loc, T, IncompleteDiagnoser))
5739 return From;
5740
5741 // Look for a conversion to an integral or enumeration type.
5742 UnresolvedSet<4>
5743 ViableConversions; // These are *potentially* viable in C++1y.
5744 UnresolvedSet<4> ExplicitConversions;
5745 const auto &Conversions =
5746 cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions();
5747
5748 bool HadMultipleCandidates =
5749 (std::distance(Conversions.begin(), Conversions.end()) > 1);
5750
5751 // To check that there is only one target type, in C++1y:
5752 QualType ToType;
5753 bool HasUniqueTargetType = true;
5754
5755 // Collect explicit or viable (potentially in C++1y) conversions.
5756 for (auto I = Conversions.begin(), E = Conversions.end(); I != E; ++I) {
5757 NamedDecl *D = (*I)->getUnderlyingDecl();
5758 CXXConversionDecl *Conversion;
5759 FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(D);
5760 if (ConvTemplate) {
5761 if (getLangOpts().CPlusPlus14)
5762 Conversion = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl());
5763 else
5764 continue; // C++11 does not consider conversion operator templates(?).
5765 } else
5766 Conversion = cast<CXXConversionDecl>(D);
5767
5768 assert((!ConvTemplate || getLangOpts().CPlusPlus14) &&(((!ConvTemplate || getLangOpts().CPlusPlus14) && "Conversion operator templates are considered potentially "
"viable in C++1y") ? static_cast<void> (0) : __assert_fail
("(!ConvTemplate || getLangOpts().CPlusPlus14) && \"Conversion operator templates are considered potentially \" \"viable in C++1y\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5770, __PRETTY_FUNCTION__))
5769 "Conversion operator templates are considered potentially "(((!ConvTemplate || getLangOpts().CPlusPlus14) && "Conversion operator templates are considered potentially "
"viable in C++1y") ? static_cast<void> (0) : __assert_fail
("(!ConvTemplate || getLangOpts().CPlusPlus14) && \"Conversion operator templates are considered potentially \" \"viable in C++1y\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5770, __PRETTY_FUNCTION__))
5770 "viable in C++1y")(((!ConvTemplate || getLangOpts().CPlusPlus14) && "Conversion operator templates are considered potentially "
"viable in C++1y") ? static_cast<void> (0) : __assert_fail
("(!ConvTemplate || getLangOpts().CPlusPlus14) && \"Conversion operator templates are considered potentially \" \"viable in C++1y\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5770, __PRETTY_FUNCTION__))
;
5771
5772 QualType CurToType = Conversion->getConversionType().getNonReferenceType();
5773 if (Converter.match(CurToType) || ConvTemplate) {
5774
5775 if (Conversion->isExplicit()) {
5776 // FIXME: For C++1y, do we need this restriction?
5777 // cf. diagnoseNoViableConversion()
5778 if (!ConvTemplate)
5779 ExplicitConversions.addDecl(I.getDecl(), I.getAccess());
5780 } else {
5781 if (!ConvTemplate && getLangOpts().CPlusPlus14) {
5782 if (ToType.isNull())
5783 ToType = CurToType.getUnqualifiedType();
5784 else if (HasUniqueTargetType &&
5785 (CurToType.getUnqualifiedType() != ToType))
5786 HasUniqueTargetType = false;
5787 }
5788 ViableConversions.addDecl(I.getDecl(), I.getAccess());
5789 }
5790 }
5791 }
5792
5793 if (getLangOpts().CPlusPlus14) {
5794 // C++1y [conv]p6:
5795 // ... An expression e of class type E appearing in such a context
5796 // is said to be contextually implicitly converted to a specified
5797 // type T and is well-formed if and only if e can be implicitly
5798 // converted to a type T that is determined as follows: E is searched
5799 // for conversion functions whose return type is cv T or reference to
5800 // cv T such that T is allowed by the context. There shall be
5801 // exactly one such T.
5802
5803 // If no unique T is found:
5804 if (ToType.isNull()) {
5805 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
5806 HadMultipleCandidates,
5807 ExplicitConversions))
5808 return ExprError();
5809 return finishContextualImplicitConversion(*this, Loc, From, Converter);
5810 }
5811
5812 // If more than one unique Ts are found:
5813 if (!HasUniqueTargetType)
5814 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
5815 ViableConversions);
5816
5817 // If one unique T is found:
5818 // First, build a candidate set from the previously recorded
5819 // potentially viable conversions.
5820 OverloadCandidateSet CandidateSet(Loc, OverloadCandidateSet::CSK_Normal);
5821 collectViableConversionCandidates(*this, From, ToType, ViableConversions,
5822 CandidateSet);
5823
5824 // Then, perform overload resolution over the candidate set.
5825 OverloadCandidateSet::iterator Best;
5826 switch (CandidateSet.BestViableFunction(*this, Loc, Best)) {
5827 case OR_Success: {
5828 // Apply this conversion.
5829 DeclAccessPair Found =
5830 DeclAccessPair::make(Best->Function, Best->FoundDecl.getAccess());
5831 if (recordConversion(*this, Loc, From, Converter, T,
5832 HadMultipleCandidates, Found))
5833 return ExprError();
5834 break;
5835 }
5836 case OR_Ambiguous:
5837 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
5838 ViableConversions);
5839 case OR_No_Viable_Function:
5840 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
5841 HadMultipleCandidates,
5842 ExplicitConversions))
5843 return ExprError();
5844 LLVM_FALLTHROUGH[[clang::fallthrough]];
5845 case OR_Deleted:
5846 // We'll complain below about a non-integral condition type.
5847 break;
5848 }
5849 } else {
5850 switch (ViableConversions.size()) {
5851 case 0: {
5852 if (diagnoseNoViableConversion(*this, Loc, From, Converter, T,
5853 HadMultipleCandidates,
5854 ExplicitConversions))
5855 return ExprError();
5856
5857 // We'll complain below about a non-integral condition type.
5858 break;
5859 }
5860 case 1: {
5861 // Apply this conversion.
5862 DeclAccessPair Found = ViableConversions[0];
5863 if (recordConversion(*this, Loc, From, Converter, T,
5864 HadMultipleCandidates, Found))
5865 return ExprError();
5866 break;
5867 }
5868 default:
5869 return diagnoseAmbiguousConversion(*this, Loc, From, Converter, T,
5870 ViableConversions);
5871 }
5872 }
5873
5874 return finishContextualImplicitConversion(*this, Loc, From, Converter);
5875}
5876
5877/// IsAcceptableNonMemberOperatorCandidate - Determine whether Fn is
5878/// an acceptable non-member overloaded operator for a call whose
5879/// arguments have types T1 (and, if non-empty, T2). This routine
5880/// implements the check in C++ [over.match.oper]p3b2 concerning
5881/// enumeration types.
5882static bool IsAcceptableNonMemberOperatorCandidate(ASTContext &Context,
5883 FunctionDecl *Fn,
5884 ArrayRef<Expr *> Args) {
5885 QualType T1 = Args[0]->getType();
5886 QualType T2 = Args.size() > 1 ? Args[1]->getType() : QualType();
5887
5888 if (T1->isDependentType() || (!T2.isNull() && T2->isDependentType()))
5889 return true;
5890
5891 if (T1->isRecordType() || (!T2.isNull() && T2->isRecordType()))
5892 return true;
5893
5894 const FunctionProtoType *Proto = Fn->getType()->getAs<FunctionProtoType>();
5895 if (Proto->getNumParams() < 1)
5896 return false;
5897
5898 if (T1->isEnumeralType()) {
5899 QualType ArgType = Proto->getParamType(0).getNonReferenceType();
5900 if (Context.hasSameUnqualifiedType(T1, ArgType))
5901 return true;
5902 }
5903
5904 if (Proto->getNumParams() < 2)
5905 return false;
5906
5907 if (!T2.isNull() && T2->isEnumeralType()) {
5908 QualType ArgType = Proto->getParamType(1).getNonReferenceType();
5909 if (Context.hasSameUnqualifiedType(T2, ArgType))
5910 return true;
5911 }
5912
5913 return false;
5914}
5915
5916/// AddOverloadCandidate - Adds the given function to the set of
5917/// candidate functions, using the given function call arguments. If
5918/// @p SuppressUserConversions, then don't allow user-defined
5919/// conversions via constructors or conversion operators.
5920///
5921/// \param PartialOverloading true if we are performing "partial" overloading
5922/// based on an incomplete set of function arguments. This feature is used by
5923/// code completion.
5924void
5925Sema::AddOverloadCandidate(FunctionDecl *Function,
5926 DeclAccessPair FoundDecl,
5927 ArrayRef<Expr *> Args,
5928 OverloadCandidateSet &CandidateSet,
5929 bool SuppressUserConversions,
5930 bool PartialOverloading,
5931 bool AllowExplicit,
5932 ConversionSequenceList EarlyConversions) {
5933 const FunctionProtoType *Proto
5934 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>());
5935 assert(Proto && "Functions without a prototype cannot be overloaded")((Proto && "Functions without a prototype cannot be overloaded"
) ? static_cast<void> (0) : __assert_fail ("Proto && \"Functions without a prototype cannot be overloaded\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5935, __PRETTY_FUNCTION__))
;
5936 assert(!Function->getDescribedFunctionTemplate() &&((!Function->getDescribedFunctionTemplate() && "Use AddTemplateOverloadCandidate for function templates"
) ? static_cast<void> (0) : __assert_fail ("!Function->getDescribedFunctionTemplate() && \"Use AddTemplateOverloadCandidate for function templates\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5937, __PRETTY_FUNCTION__))
5937 "Use AddTemplateOverloadCandidate for function templates")((!Function->getDescribedFunctionTemplate() && "Use AddTemplateOverloadCandidate for function templates"
) ? static_cast<void> (0) : __assert_fail ("!Function->getDescribedFunctionTemplate() && \"Use AddTemplateOverloadCandidate for function templates\""
, "/build/llvm-toolchain-snapshot-8~svn345461/tools/clang/lib/Sema/SemaOverload.cpp"
, 5937, __PRETTY_FUNCTION__))
;
5938
5939 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) {
5940 if (!isa<CXXConstructorDecl>(Method)) {
5941 // If we get here, it's because we're calling a member function
5942 // that is named without a member access expression (e.g.,
5943 // "this->f") that was either written explicitly or created
5944 // implicitly. This can happen with a qualified call to a member
5945 // function, e.g., X::f(). We use an empty type for the implied
5946 // object argument (C++ [over.call.func]p3), and the acting context
5947 // is irrelevant.
5948 AddMethodCandidate(Method, FoundDecl, Method->getParent(), QualType(),
5949 Expr::Classification::makeSimpleLValue(), Args,
5950 CandidateSet, SuppressUserConversions,
5951 PartialOverloading, Early