Bug Summary

File:clang/lib/Sema/SemaExprCXX.cpp
Warning:line 3820, column 3
Called C++ object pointer is null

Annotated Source Code

Press '?' to see keyboard shortcuts

clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaExprCXX.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 -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Sema -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/include -D NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/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-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-09-04-040900-46481-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/clang/lib/Sema/SemaExprCXX.cpp
1//===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// Implements semantic analysis for C++ expressions.
11///
12//===----------------------------------------------------------------------===//
13
14#include "clang/Sema/Template.h"
15#include "clang/Sema/SemaInternal.h"
16#include "TreeTransform.h"
17#include "TypeLocBuilder.h"
18#include "clang/AST/ASTContext.h"
19#include "clang/AST/ASTLambda.h"
20#include "clang/AST/CXXInheritance.h"
21#include "clang/AST/CharUnits.h"
22#include "clang/AST/DeclObjC.h"
23#include "clang/AST/ExprCXX.h"
24#include "clang/AST/ExprObjC.h"
25#include "clang/AST/RecursiveASTVisitor.h"
26#include "clang/AST/TypeLoc.h"
27#include "clang/Basic/AlignedAllocation.h"
28#include "clang/Basic/PartialDiagnostic.h"
29#include "clang/Basic/TargetInfo.h"
30#include "clang/Lex/Preprocessor.h"
31#include "clang/Sema/DeclSpec.h"
32#include "clang/Sema/Initialization.h"
33#include "clang/Sema/Lookup.h"
34#include "clang/Sema/ParsedTemplate.h"
35#include "clang/Sema/Scope.h"
36#include "clang/Sema/ScopeInfo.h"
37#include "clang/Sema/SemaLambda.h"
38#include "clang/Sema/TemplateDeduction.h"
39#include "llvm/ADT/APInt.h"
40#include "llvm/ADT/STLExtras.h"
41#include "llvm/Support/ErrorHandling.h"
42using namespace clang;
43using namespace sema;
44
45/// Handle the result of the special case name lookup for inheriting
46/// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as
47/// constructor names in member using declarations, even if 'X' is not the
48/// name of the corresponding type.
49ParsedType Sema::getInheritingConstructorName(CXXScopeSpec &SS,
50 SourceLocation NameLoc,
51 IdentifierInfo &Name) {
52 NestedNameSpecifier *NNS = SS.getScopeRep();
53
54 // Convert the nested-name-specifier into a type.
55 QualType Type;
56 switch (NNS->getKind()) {
57 case NestedNameSpecifier::TypeSpec:
58 case NestedNameSpecifier::TypeSpecWithTemplate:
59 Type = QualType(NNS->getAsType(), 0);
60 break;
61
62 case NestedNameSpecifier::Identifier:
63 // Strip off the last layer of the nested-name-specifier and build a
64 // typename type for it.
65 assert(NNS->getAsIdentifier() == &Name && "not a constructor name")(static_cast<void> (0));
66 Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(),
67 NNS->getAsIdentifier());
68 break;
69
70 case NestedNameSpecifier::Global:
71 case NestedNameSpecifier::Super:
72 case NestedNameSpecifier::Namespace:
73 case NestedNameSpecifier::NamespaceAlias:
74 llvm_unreachable("Nested name specifier is not a type for inheriting ctor")__builtin_unreachable();
75 }
76
77 // This reference to the type is located entirely at the location of the
78 // final identifier in the qualified-id.
79 return CreateParsedType(Type,
80 Context.getTrivialTypeSourceInfo(Type, NameLoc));
81}
82
83ParsedType Sema::getConstructorName(IdentifierInfo &II,
84 SourceLocation NameLoc,
85 Scope *S, CXXScopeSpec &SS,
86 bool EnteringContext) {
87 CXXRecordDecl *CurClass = getCurrentClass(S, &SS);
88 assert(CurClass && &II == CurClass->getIdentifier() &&(static_cast<void> (0))
89 "not a constructor name")(static_cast<void> (0));
90
91 // When naming a constructor as a member of a dependent context (eg, in a
92 // friend declaration or an inherited constructor declaration), form an
93 // unresolved "typename" type.
94 if (CurClass->isDependentContext() && !EnteringContext && SS.getScopeRep()) {
95 QualType T = Context.getDependentNameType(ETK_None, SS.getScopeRep(), &II);
96 return ParsedType::make(T);
97 }
98
99 if (SS.isNotEmpty() && RequireCompleteDeclContext(SS, CurClass))
100 return ParsedType();
101
102 // Find the injected-class-name declaration. Note that we make no attempt to
103 // diagnose cases where the injected-class-name is shadowed: the only
104 // declaration that can validly shadow the injected-class-name is a
105 // non-static data member, and if the class contains both a non-static data
106 // member and a constructor then it is ill-formed (we check that in
107 // CheckCompletedCXXClass).
108 CXXRecordDecl *InjectedClassName = nullptr;
109 for (NamedDecl *ND : CurClass->lookup(&II)) {
110 auto *RD = dyn_cast<CXXRecordDecl>(ND);
111 if (RD && RD->isInjectedClassName()) {
112 InjectedClassName = RD;
113 break;
114 }
115 }
116 if (!InjectedClassName) {
117 if (!CurClass->isInvalidDecl()) {
118 // FIXME: RequireCompleteDeclContext doesn't check dependent contexts
119 // properly. Work around it here for now.
120 Diag(SS.getLastQualifierNameLoc(),
121 diag::err_incomplete_nested_name_spec) << CurClass << SS.getRange();
122 }
123 return ParsedType();
124 }
125
126 QualType T = Context.getTypeDeclType(InjectedClassName);
127 DiagnoseUseOfDecl(InjectedClassName, NameLoc);
128 MarkAnyDeclReferenced(NameLoc, InjectedClassName, /*OdrUse=*/false);
129
130 return ParsedType::make(T);
131}
132
133ParsedType Sema::getDestructorName(SourceLocation TildeLoc,
134 IdentifierInfo &II,
135 SourceLocation NameLoc,
136 Scope *S, CXXScopeSpec &SS,
137 ParsedType ObjectTypePtr,
138 bool EnteringContext) {
139 // Determine where to perform name lookup.
140
141 // FIXME: This area of the standard is very messy, and the current
142 // wording is rather unclear about which scopes we search for the
143 // destructor name; see core issues 399 and 555. Issue 399 in
144 // particular shows where the current description of destructor name
145 // lookup is completely out of line with existing practice, e.g.,
146 // this appears to be ill-formed:
147 //
148 // namespace N {
149 // template <typename T> struct S {
150 // ~S();
151 // };
152 // }
153 //
154 // void f(N::S<int>* s) {
155 // s->N::S<int>::~S();
156 // }
157 //
158 // See also PR6358 and PR6359.
159 //
160 // For now, we accept all the cases in which the name given could plausibly
161 // be interpreted as a correct destructor name, issuing off-by-default
162 // extension diagnostics on the cases that don't strictly conform to the
163 // C++20 rules. This basically means we always consider looking in the
164 // nested-name-specifier prefix, the complete nested-name-specifier, and
165 // the scope, and accept if we find the expected type in any of the three
166 // places.
167
168 if (SS.isInvalid())
169 return nullptr;
170
171 // Whether we've failed with a diagnostic already.
172 bool Failed = false;
173
174 llvm::SmallVector<NamedDecl*, 8> FoundDecls;
175 llvm::SmallPtrSet<CanonicalDeclPtr<Decl>, 8> FoundDeclSet;
176
177 // If we have an object type, it's because we are in a
178 // pseudo-destructor-expression or a member access expression, and
179 // we know what type we're looking for.
180 QualType SearchType =
181 ObjectTypePtr ? GetTypeFromParser(ObjectTypePtr) : QualType();
182
183 auto CheckLookupResult = [&](LookupResult &Found) -> ParsedType {
184 auto IsAcceptableResult = [&](NamedDecl *D) -> bool {
185 auto *Type = dyn_cast<TypeDecl>(D->getUnderlyingDecl());
186 if (!Type)
187 return false;
188
189 if (SearchType.isNull() || SearchType->isDependentType())
190 return true;
191
192 QualType T = Context.getTypeDeclType(Type);
193 return Context.hasSameUnqualifiedType(T, SearchType);
194 };
195
196 unsigned NumAcceptableResults = 0;
197 for (NamedDecl *D : Found) {
198 if (IsAcceptableResult(D))
199 ++NumAcceptableResults;
200
201 // Don't list a class twice in the lookup failure diagnostic if it's
202 // found by both its injected-class-name and by the name in the enclosing
203 // scope.
204 if (auto *RD = dyn_cast<CXXRecordDecl>(D))
205 if (RD->isInjectedClassName())
206 D = cast<NamedDecl>(RD->getParent());
207
208 if (FoundDeclSet.insert(D).second)
209 FoundDecls.push_back(D);
210 }
211
212 // As an extension, attempt to "fix" an ambiguity by erasing all non-type
213 // results, and all non-matching results if we have a search type. It's not
214 // clear what the right behavior is if destructor lookup hits an ambiguity,
215 // but other compilers do generally accept at least some kinds of
216 // ambiguity.
217 if (Found.isAmbiguous() && NumAcceptableResults == 1) {
218 Diag(NameLoc, diag::ext_dtor_name_ambiguous);
219 LookupResult::Filter F = Found.makeFilter();
220 while (F.hasNext()) {
221 NamedDecl *D = F.next();
222 if (auto *TD = dyn_cast<TypeDecl>(D->getUnderlyingDecl()))
223 Diag(D->getLocation(), diag::note_destructor_type_here)
224 << Context.getTypeDeclType(TD);
225 else
226 Diag(D->getLocation(), diag::note_destructor_nontype_here);
227
228 if (!IsAcceptableResult(D))
229 F.erase();
230 }
231 F.done();
232 }
233
234 if (Found.isAmbiguous())
235 Failed = true;
236
237 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
238 if (IsAcceptableResult(Type)) {
239 QualType T = Context.getTypeDeclType(Type);
240 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
241 return CreateParsedType(T,
242 Context.getTrivialTypeSourceInfo(T, NameLoc));
243 }
244 }
245
246 return nullptr;
247 };
248
249 bool IsDependent = false;
250
251 auto LookupInObjectType = [&]() -> ParsedType {
252 if (Failed || SearchType.isNull())
253 return nullptr;
254
255 IsDependent |= SearchType->isDependentType();
256
257 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
258 DeclContext *LookupCtx = computeDeclContext(SearchType);
259 if (!LookupCtx)
260 return nullptr;
261 LookupQualifiedName(Found, LookupCtx);
262 return CheckLookupResult(Found);
263 };
264
265 auto LookupInNestedNameSpec = [&](CXXScopeSpec &LookupSS) -> ParsedType {
266 if (Failed)
267 return nullptr;
268
269 IsDependent |= isDependentScopeSpecifier(LookupSS);
270 DeclContext *LookupCtx = computeDeclContext(LookupSS, EnteringContext);
271 if (!LookupCtx)
272 return nullptr;
273
274 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
275 if (RequireCompleteDeclContext(LookupSS, LookupCtx)) {
276 Failed = true;
277 return nullptr;
278 }
279 LookupQualifiedName(Found, LookupCtx);
280 return CheckLookupResult(Found);
281 };
282
283 auto LookupInScope = [&]() -> ParsedType {
284 if (Failed || !S)
285 return nullptr;
286
287 LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
288 LookupName(Found, S);
289 return CheckLookupResult(Found);
290 };
291
292 // C++2a [basic.lookup.qual]p6:
293 // In a qualified-id of the form
294 //
295 // nested-name-specifier[opt] type-name :: ~ type-name
296 //
297 // the second type-name is looked up in the same scope as the first.
298 //
299 // We interpret this as meaning that if you do a dual-scope lookup for the
300 // first name, you also do a dual-scope lookup for the second name, per
301 // C++ [basic.lookup.classref]p4:
302 //
303 // If the id-expression in a class member access is a qualified-id of the
304 // form
305 //
306 // class-name-or-namespace-name :: ...
307 //
308 // the class-name-or-namespace-name following the . or -> is first looked
309 // up in the class of the object expression and the name, if found, is used.
310 // Otherwise, it is looked up in the context of the entire
311 // postfix-expression.
312 //
313 // This looks in the same scopes as for an unqualified destructor name:
314 //
315 // C++ [basic.lookup.classref]p3:
316 // If the unqualified-id is ~ type-name, the type-name is looked up
317 // in the context of the entire postfix-expression. If the type T
318 // of the object expression is of a class type C, the type-name is
319 // also looked up in the scope of class C. At least one of the
320 // lookups shall find a name that refers to cv T.
321 //
322 // FIXME: The intent is unclear here. Should type-name::~type-name look in
323 // the scope anyway if it finds a non-matching name declared in the class?
324 // If both lookups succeed and find a dependent result, which result should
325 // we retain? (Same question for p->~type-name().)
326
327 if (NestedNameSpecifier *Prefix =
328 SS.isSet() ? SS.getScopeRep()->getPrefix() : nullptr) {
329 // This is
330 //
331 // nested-name-specifier type-name :: ~ type-name
332 //
333 // Look for the second type-name in the nested-name-specifier.
334 CXXScopeSpec PrefixSS;
335 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
336 if (ParsedType T = LookupInNestedNameSpec(PrefixSS))
337 return T;
338 } else {
339 // This is one of
340 //
341 // type-name :: ~ type-name
342 // ~ type-name
343 //
344 // Look in the scope and (if any) the object type.
345 if (ParsedType T = LookupInScope())
346 return T;
347 if (ParsedType T = LookupInObjectType())
348 return T;
349 }
350
351 if (Failed)
352 return nullptr;
353
354 if (IsDependent) {
355 // We didn't find our type, but that's OK: it's dependent anyway.
356
357 // FIXME: What if we have no nested-name-specifier?
358 QualType T = CheckTypenameType(ETK_None, SourceLocation(),
359 SS.getWithLocInContext(Context),
360 II, NameLoc);
361 return ParsedType::make(T);
362 }
363
364 // The remaining cases are all non-standard extensions imitating the behavior
365 // of various other compilers.
366 unsigned NumNonExtensionDecls = FoundDecls.size();
367
368 if (SS.isSet()) {
369 // For compatibility with older broken C++ rules and existing code,
370 //
371 // nested-name-specifier :: ~ type-name
372 //
373 // also looks for type-name within the nested-name-specifier.
374 if (ParsedType T = LookupInNestedNameSpec(SS)) {
375 Diag(SS.getEndLoc(), diag::ext_dtor_named_in_wrong_scope)
376 << SS.getRange()
377 << FixItHint::CreateInsertion(SS.getEndLoc(),
378 ("::" + II.getName()).str());
379 return T;
380 }
381
382 // For compatibility with other compilers and older versions of Clang,
383 //
384 // nested-name-specifier type-name :: ~ type-name
385 //
386 // also looks for type-name in the scope. Unfortunately, we can't
387 // reasonably apply this fallback for dependent nested-name-specifiers.
388 if (SS.getScopeRep()->getPrefix()) {
389 if (ParsedType T = LookupInScope()) {
390 Diag(SS.getEndLoc(), diag::ext_qualified_dtor_named_in_lexical_scope)
391 << FixItHint::CreateRemoval(SS.getRange());
392 Diag(FoundDecls.back()->getLocation(), diag::note_destructor_type_here)
393 << GetTypeFromParser(T);
394 return T;
395 }
396 }
397 }
398
399 // We didn't find anything matching; tell the user what we did find (if
400 // anything).
401
402 // Don't tell the user about declarations we shouldn't have found.
403 FoundDecls.resize(NumNonExtensionDecls);
404
405 // List types before non-types.
406 std::stable_sort(FoundDecls.begin(), FoundDecls.end(),
407 [](NamedDecl *A, NamedDecl *B) {
408 return isa<TypeDecl>(A->getUnderlyingDecl()) >
409 isa<TypeDecl>(B->getUnderlyingDecl());
410 });
411
412 // Suggest a fixit to properly name the destroyed type.
413 auto MakeFixItHint = [&]{
414 const CXXRecordDecl *Destroyed = nullptr;
415 // FIXME: If we have a scope specifier, suggest its last component?
416 if (!SearchType.isNull())
417 Destroyed = SearchType->getAsCXXRecordDecl();
418 else if (S)
419 Destroyed = dyn_cast_or_null<CXXRecordDecl>(S->getEntity());
420 if (Destroyed)
421 return FixItHint::CreateReplacement(SourceRange(NameLoc),
422 Destroyed->getNameAsString());
423 return FixItHint();
424 };
425
426 if (FoundDecls.empty()) {
427 // FIXME: Attempt typo-correction?
428 Diag(NameLoc, diag::err_undeclared_destructor_name)
429 << &II << MakeFixItHint();
430 } else if (!SearchType.isNull() && FoundDecls.size() == 1) {
431 if (auto *TD = dyn_cast<TypeDecl>(FoundDecls[0]->getUnderlyingDecl())) {
432 assert(!SearchType.isNull() &&(static_cast<void> (0))
433 "should only reject a type result if we have a search type")(static_cast<void> (0));
434 QualType T = Context.getTypeDeclType(TD);
435 Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
436 << T << SearchType << MakeFixItHint();
437 } else {
438 Diag(NameLoc, diag::err_destructor_expr_nontype)
439 << &II << MakeFixItHint();
440 }
441 } else {
442 Diag(NameLoc, SearchType.isNull() ? diag::err_destructor_name_nontype
443 : diag::err_destructor_expr_mismatch)
444 << &II << SearchType << MakeFixItHint();
445 }
446
447 for (NamedDecl *FoundD : FoundDecls) {
448 if (auto *TD = dyn_cast<TypeDecl>(FoundD->getUnderlyingDecl()))
449 Diag(FoundD->getLocation(), diag::note_destructor_type_here)
450 << Context.getTypeDeclType(TD);
451 else
452 Diag(FoundD->getLocation(), diag::note_destructor_nontype_here)
453 << FoundD;
454 }
455
456 return nullptr;
457}
458
459ParsedType Sema::getDestructorTypeForDecltype(const DeclSpec &DS,
460 ParsedType ObjectType) {
461 if (DS.getTypeSpecType() == DeclSpec::TST_error)
462 return nullptr;
463
464 if (DS.getTypeSpecType() == DeclSpec::TST_decltype_auto) {
465 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
466 return nullptr;
467 }
468
469 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&(static_cast<void> (0))
470 "unexpected type in getDestructorType")(static_cast<void> (0));
471 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
472
473 // If we know the type of the object, check that the correct destructor
474 // type was named now; we can give better diagnostics this way.
475 QualType SearchType = GetTypeFromParser(ObjectType);
476 if (!SearchType.isNull() && !SearchType->isDependentType() &&
477 !Context.hasSameUnqualifiedType(T, SearchType)) {
478 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
479 << T << SearchType;
480 return nullptr;
481 }
482
483 return ParsedType::make(T);
484}
485
486bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
487 const UnqualifiedId &Name, bool IsUDSuffix) {
488 assert(Name.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId)(static_cast<void> (0));
489 if (!IsUDSuffix) {
490 // [over.literal] p8
491 //
492 // double operator""_Bq(long double); // OK: not a reserved identifier
493 // double operator"" _Bq(long double); // ill-formed, no diagnostic required
494 IdentifierInfo *II = Name.Identifier;
495 ReservedIdentifierStatus Status = II->isReserved(PP.getLangOpts());
496 SourceLocation Loc = Name.getEndLoc();
497 if (Status != ReservedIdentifierStatus::NotReserved &&
498 !PP.getSourceManager().isInSystemHeader(Loc)) {
499 Diag(Loc, diag::warn_reserved_extern_symbol)
500 << II << static_cast<int>(Status)
501 << FixItHint::CreateReplacement(
502 Name.getSourceRange(),
503 (StringRef("operator\"\"") + II->getName()).str());
504 }
505 }
506
507 if (!SS.isValid())
508 return false;
509
510 switch (SS.getScopeRep()->getKind()) {
511 case NestedNameSpecifier::Identifier:
512 case NestedNameSpecifier::TypeSpec:
513 case NestedNameSpecifier::TypeSpecWithTemplate:
514 // Per C++11 [over.literal]p2, literal operators can only be declared at
515 // namespace scope. Therefore, this unqualified-id cannot name anything.
516 // Reject it early, because we have no AST representation for this in the
517 // case where the scope is dependent.
518 Diag(Name.getBeginLoc(), diag::err_literal_operator_id_outside_namespace)
519 << SS.getScopeRep();
520 return true;
521
522 case NestedNameSpecifier::Global:
523 case NestedNameSpecifier::Super:
524 case NestedNameSpecifier::Namespace:
525 case NestedNameSpecifier::NamespaceAlias:
526 return false;
527 }
528
529 llvm_unreachable("unknown nested name specifier kind")__builtin_unreachable();
530}
531
532/// Build a C++ typeid expression with a type operand.
533ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
534 SourceLocation TypeidLoc,
535 TypeSourceInfo *Operand,
536 SourceLocation RParenLoc) {
537 // C++ [expr.typeid]p4:
538 // The top-level cv-qualifiers of the lvalue expression or the type-id
539 // that is the operand of typeid are always ignored.
540 // If the type of the type-id is a class type or a reference to a class
541 // type, the class shall be completely-defined.
542 Qualifiers Quals;
543 QualType T
544 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
545 Quals);
546 if (T->getAs<RecordType>() &&
547 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
548 return ExprError();
549
550 if (T->isVariablyModifiedType())
551 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
552
553 if (CheckQualifiedFunctionForTypeId(T, TypeidLoc))
554 return ExprError();
555
556 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
557 SourceRange(TypeidLoc, RParenLoc));
558}
559
560/// Build a C++ typeid expression with an expression operand.
561ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
562 SourceLocation TypeidLoc,
563 Expr *E,
564 SourceLocation RParenLoc) {
565 bool WasEvaluated = false;
566 if (E && !E->isTypeDependent()) {
567 if (E->getType()->isPlaceholderType()) {
568 ExprResult result = CheckPlaceholderExpr(E);
569 if (result.isInvalid()) return ExprError();
570 E = result.get();
571 }
572
573 QualType T = E->getType();
574 if (const RecordType *RecordT = T->getAs<RecordType>()) {
575 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
576 // C++ [expr.typeid]p3:
577 // [...] If the type of the expression is a class type, the class
578 // shall be completely-defined.
579 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
580 return ExprError();
581
582 // C++ [expr.typeid]p3:
583 // When typeid is applied to an expression other than an glvalue of a
584 // polymorphic class type [...] [the] expression is an unevaluated
585 // operand. [...]
586 if (RecordD->isPolymorphic() && E->isGLValue()) {
587 if (isUnevaluatedContext()) {
588 // The operand was processed in unevaluated context, switch the
589 // context and recheck the subexpression.
590 ExprResult Result = TransformToPotentiallyEvaluated(E);
591 if (Result.isInvalid())
592 return ExprError();
593 E = Result.get();
594 }
595
596 // We require a vtable to query the type at run time.
597 MarkVTableUsed(TypeidLoc, RecordD);
598 WasEvaluated = true;
599 }
600 }
601
602 ExprResult Result = CheckUnevaluatedOperand(E);
603 if (Result.isInvalid())
604 return ExprError();
605 E = Result.get();
606
607 // C++ [expr.typeid]p4:
608 // [...] If the type of the type-id is a reference to a possibly
609 // cv-qualified type, the result of the typeid expression refers to a
610 // std::type_info object representing the cv-unqualified referenced
611 // type.
612 Qualifiers Quals;
613 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
614 if (!Context.hasSameType(T, UnqualT)) {
615 T = UnqualT;
616 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
617 }
618 }
619
620 if (E->getType()->isVariablyModifiedType())
621 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
622 << E->getType());
623 else if (!inTemplateInstantiation() &&
624 E->HasSideEffects(Context, WasEvaluated)) {
625 // The expression operand for typeid is in an unevaluated expression
626 // context, so side effects could result in unintended consequences.
627 Diag(E->getExprLoc(), WasEvaluated
628 ? diag::warn_side_effects_typeid
629 : diag::warn_side_effects_unevaluated_context);
630 }
631
632 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
633 SourceRange(TypeidLoc, RParenLoc));
634}
635
636/// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
637ExprResult
638Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
639 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
640 // typeid is not supported in OpenCL.
641 if (getLangOpts().OpenCLCPlusPlus) {
642 return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
643 << "typeid");
644 }
645
646 // Find the std::type_info type.
647 if (!getStdNamespace())
648 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
649
650 if (!CXXTypeInfoDecl) {
651 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
652 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
653 LookupQualifiedName(R, getStdNamespace());
654 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
655 // Microsoft's typeinfo doesn't have type_info in std but in the global
656 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
657 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
658 LookupQualifiedName(R, Context.getTranslationUnitDecl());
659 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
660 }
661 if (!CXXTypeInfoDecl)
662 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
663 }
664
665 if (!getLangOpts().RTTI) {
666 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
667 }
668
669 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
670
671 if (isType) {
672 // The operand is a type; handle it as such.
673 TypeSourceInfo *TInfo = nullptr;
674 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
675 &TInfo);
676 if (T.isNull())
677 return ExprError();
678
679 if (!TInfo)
680 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
681
682 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
683 }
684
685 // The operand is an expression.
686 ExprResult Result =
687 BuildCXXTypeId(TypeInfoType, OpLoc, (Expr *)TyOrExpr, RParenLoc);
688
689 if (!getLangOpts().RTTIData && !Result.isInvalid())
690 if (auto *CTE = dyn_cast<CXXTypeidExpr>(Result.get()))
691 if (CTE->isPotentiallyEvaluated() && !CTE->isMostDerived(Context))
692 Diag(OpLoc, diag::warn_no_typeid_with_rtti_disabled)
693 << (getDiagnostics().getDiagnosticOptions().getFormat() ==
694 DiagnosticOptions::MSVC);
695 return Result;
696}
697
698/// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
699/// a single GUID.
700static void
701getUuidAttrOfType(Sema &SemaRef, QualType QT,
702 llvm::SmallSetVector<const UuidAttr *, 1> &UuidAttrs) {
703 // Optionally remove one level of pointer, reference or array indirection.
704 const Type *Ty = QT.getTypePtr();
705 if (QT->isPointerType() || QT->isReferenceType())
706 Ty = QT->getPointeeType().getTypePtr();
707 else if (QT->isArrayType())
708 Ty = Ty->getBaseElementTypeUnsafe();
709
710 const auto *TD = Ty->getAsTagDecl();
711 if (!TD)
712 return;
713
714 if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
715 UuidAttrs.insert(Uuid);
716 return;
717 }
718
719 // __uuidof can grab UUIDs from template arguments.
720 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
721 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
722 for (const TemplateArgument &TA : TAL.asArray()) {
723 const UuidAttr *UuidForTA = nullptr;
724 if (TA.getKind() == TemplateArgument::Type)
725 getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
726 else if (TA.getKind() == TemplateArgument::Declaration)
727 getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
728
729 if (UuidForTA)
730 UuidAttrs.insert(UuidForTA);
731 }
732 }
733}
734
735/// Build a Microsoft __uuidof expression with a type operand.
736ExprResult Sema::BuildCXXUuidof(QualType Type,
737 SourceLocation TypeidLoc,
738 TypeSourceInfo *Operand,
739 SourceLocation RParenLoc) {
740 MSGuidDecl *Guid = nullptr;
741 if (!Operand->getType()->isDependentType()) {
742 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
743 getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
744 if (UuidAttrs.empty())
745 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
746 if (UuidAttrs.size() > 1)
747 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
748 Guid = UuidAttrs.back()->getGuidDecl();
749 }
750
751 return new (Context)
752 CXXUuidofExpr(Type, Operand, Guid, SourceRange(TypeidLoc, RParenLoc));
753}
754
755/// Build a Microsoft __uuidof expression with an expression operand.
756ExprResult Sema::BuildCXXUuidof(QualType Type, SourceLocation TypeidLoc,
757 Expr *E, SourceLocation RParenLoc) {
758 MSGuidDecl *Guid = nullptr;
759 if (!E->getType()->isDependentType()) {
760 if (E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
761 // A null pointer results in {00000000-0000-0000-0000-000000000000}.
762 Guid = Context.getMSGuidDecl(MSGuidDecl::Parts{});
763 } else {
764 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
765 getUuidAttrOfType(*this, E->getType(), UuidAttrs);
766 if (UuidAttrs.empty())
767 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
768 if (UuidAttrs.size() > 1)
769 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
770 Guid = UuidAttrs.back()->getGuidDecl();
771 }
772 }
773
774 return new (Context)
775 CXXUuidofExpr(Type, E, Guid, SourceRange(TypeidLoc, RParenLoc));
776}
777
778/// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
779ExprResult
780Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
781 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
782 QualType GuidType = Context.getMSGuidType();
783 GuidType.addConst();
784
785 if (isType) {
786 // The operand is a type; handle it as such.
787 TypeSourceInfo *TInfo = nullptr;
788 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
789 &TInfo);
790 if (T.isNull())
791 return ExprError();
792
793 if (!TInfo)
794 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
795
796 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
797 }
798
799 // The operand is an expression.
800 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
801}
802
803/// ActOnCXXBoolLiteral - Parse {true,false} literals.
804ExprResult
805Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
806 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&(static_cast<void> (0))
807 "Unknown C++ Boolean value!")(static_cast<void> (0));
808 return new (Context)
809 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
810}
811
812/// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
813ExprResult
814Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
815 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
816}
817
818/// ActOnCXXThrow - Parse throw expressions.
819ExprResult
820Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
821 bool IsThrownVarInScope = false;
822 if (Ex) {
823 // C++0x [class.copymove]p31:
824 // When certain criteria are met, an implementation is allowed to omit the
825 // copy/move construction of a class object [...]
826 //
827 // - in a throw-expression, when the operand is the name of a
828 // non-volatile automatic object (other than a function or catch-
829 // clause parameter) whose scope does not extend beyond the end of the
830 // innermost enclosing try-block (if there is one), the copy/move
831 // operation from the operand to the exception object (15.1) can be
832 // omitted by constructing the automatic object directly into the
833 // exception object
834 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
835 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
836 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
837 for( ; S; S = S->getParent()) {
838 if (S->isDeclScope(Var)) {
839 IsThrownVarInScope = true;
840 break;
841 }
842
843 if (S->getFlags() &
844 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
845 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
846 Scope::TryScope))
847 break;
848 }
849 }
850 }
851 }
852
853 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
854}
855
856ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
857 bool IsThrownVarInScope) {
858 // Don't report an error if 'throw' is used in system headers.
859 if (!getLangOpts().CXXExceptions &&
860 !getSourceManager().isInSystemHeader(OpLoc) && !getLangOpts().CUDA) {
861 // Delay error emission for the OpenMP device code.
862 targetDiag(OpLoc, diag::err_exceptions_disabled) << "throw";
863 }
864
865 // Exceptions aren't allowed in CUDA device code.
866 if (getLangOpts().CUDA)
867 CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
868 << "throw" << CurrentCUDATarget();
869
870 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
871 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
872
873 if (Ex && !Ex->isTypeDependent()) {
874 // Initialize the exception result. This implicitly weeds out
875 // abstract types or types with inaccessible copy constructors.
876
877 // C++0x [class.copymove]p31:
878 // When certain criteria are met, an implementation is allowed to omit the
879 // copy/move construction of a class object [...]
880 //
881 // - in a throw-expression, when the operand is the name of a
882 // non-volatile automatic object (other than a function or
883 // catch-clause
884 // parameter) whose scope does not extend beyond the end of the
885 // innermost enclosing try-block (if there is one), the copy/move
886 // operation from the operand to the exception object (15.1) can be
887 // omitted by constructing the automatic object directly into the
888 // exception object
889 NamedReturnInfo NRInfo =
890 IsThrownVarInScope ? getNamedReturnInfo(Ex) : NamedReturnInfo();
891
892 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
893 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
894 return ExprError();
895
896 InitializedEntity Entity = InitializedEntity::InitializeException(
897 OpLoc, ExceptionObjectTy,
898 /*NRVO=*/NRInfo.isCopyElidable());
899 ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRInfo, Ex);
900 if (Res.isInvalid())
901 return ExprError();
902 Ex = Res.get();
903 }
904
905 // PPC MMA non-pointer types are not allowed as throw expr types.
906 if (Ex && Context.getTargetInfo().getTriple().isPPC64())
907 CheckPPCMMAType(Ex->getType(), Ex->getBeginLoc());
908
909 return new (Context)
910 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
911}
912
913static void
914collectPublicBases(CXXRecordDecl *RD,
915 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
916 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
917 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
918 bool ParentIsPublic) {
919 for (const CXXBaseSpecifier &BS : RD->bases()) {
920 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
921 bool NewSubobject;
922 // Virtual bases constitute the same subobject. Non-virtual bases are
923 // always distinct subobjects.
924 if (BS.isVirtual())
925 NewSubobject = VBases.insert(BaseDecl).second;
926 else
927 NewSubobject = true;
928
929 if (NewSubobject)
930 ++SubobjectsSeen[BaseDecl];
931
932 // Only add subobjects which have public access throughout the entire chain.
933 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
934 if (PublicPath)
935 PublicSubobjectsSeen.insert(BaseDecl);
936
937 // Recurse on to each base subobject.
938 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
939 PublicPath);
940 }
941}
942
943static void getUnambiguousPublicSubobjects(
944 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
945 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
946 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
947 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
948 SubobjectsSeen[RD] = 1;
949 PublicSubobjectsSeen.insert(RD);
950 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
951 /*ParentIsPublic=*/true);
952
953 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
954 // Skip ambiguous objects.
955 if (SubobjectsSeen[PublicSubobject] > 1)
956 continue;
957
958 Objects.push_back(PublicSubobject);
959 }
960}
961
962/// CheckCXXThrowOperand - Validate the operand of a throw.
963bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
964 QualType ExceptionObjectTy, Expr *E) {
965 // If the type of the exception would be an incomplete type or a pointer
966 // to an incomplete type other than (cv) void the program is ill-formed.
967 QualType Ty = ExceptionObjectTy;
968 bool isPointer = false;
969 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
970 Ty = Ptr->getPointeeType();
971 isPointer = true;
972 }
973 if (!isPointer || !Ty->isVoidType()) {
974 if (RequireCompleteType(ThrowLoc, Ty,
975 isPointer ? diag::err_throw_incomplete_ptr
976 : diag::err_throw_incomplete,
977 E->getSourceRange()))
978 return true;
979
980 if (!isPointer && Ty->isSizelessType()) {
981 Diag(ThrowLoc, diag::err_throw_sizeless) << Ty << E->getSourceRange();
982 return true;
983 }
984
985 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
986 diag::err_throw_abstract_type, E))
987 return true;
988 }
989
990 // If the exception has class type, we need additional handling.
991 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
992 if (!RD)
993 return false;
994
995 // If we are throwing a polymorphic class type or pointer thereof,
996 // exception handling will make use of the vtable.
997 MarkVTableUsed(ThrowLoc, RD);
998
999 // If a pointer is thrown, the referenced object will not be destroyed.
1000 if (isPointer)
1001 return false;
1002
1003 // If the class has a destructor, we must be able to call it.
1004 if (!RD->hasIrrelevantDestructor()) {
1005 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
1006 MarkFunctionReferenced(E->getExprLoc(), Destructor);
1007 CheckDestructorAccess(E->getExprLoc(), Destructor,
1008 PDiag(diag::err_access_dtor_exception) << Ty);
1009 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
1010 return true;
1011 }
1012 }
1013
1014 // The MSVC ABI creates a list of all types which can catch the exception
1015 // object. This list also references the appropriate copy constructor to call
1016 // if the object is caught by value and has a non-trivial copy constructor.
1017 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1018 // We are only interested in the public, unambiguous bases contained within
1019 // the exception object. Bases which are ambiguous or otherwise
1020 // inaccessible are not catchable types.
1021 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
1022 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
1023
1024 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
1025 // Attempt to lookup the copy constructor. Various pieces of machinery
1026 // will spring into action, like template instantiation, which means this
1027 // cannot be a simple walk of the class's decls. Instead, we must perform
1028 // lookup and overload resolution.
1029 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
1030 if (!CD || CD->isDeleted())
1031 continue;
1032
1033 // Mark the constructor referenced as it is used by this throw expression.
1034 MarkFunctionReferenced(E->getExprLoc(), CD);
1035
1036 // Skip this copy constructor if it is trivial, we don't need to record it
1037 // in the catchable type data.
1038 if (CD->isTrivial())
1039 continue;
1040
1041 // The copy constructor is non-trivial, create a mapping from this class
1042 // type to this constructor.
1043 // N.B. The selection of copy constructor is not sensitive to this
1044 // particular throw-site. Lookup will be performed at the catch-site to
1045 // ensure that the copy constructor is, in fact, accessible (via
1046 // friendship or any other means).
1047 Context.addCopyConstructorForExceptionObject(Subobject, CD);
1048
1049 // We don't keep the instantiated default argument expressions around so
1050 // we must rebuild them here.
1051 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
1052 if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
1053 return true;
1054 }
1055 }
1056 }
1057
1058 // Under the Itanium C++ ABI, memory for the exception object is allocated by
1059 // the runtime with no ability for the compiler to request additional
1060 // alignment. Warn if the exception type requires alignment beyond the minimum
1061 // guaranteed by the target C++ runtime.
1062 if (Context.getTargetInfo().getCXXABI().isItaniumFamily()) {
1063 CharUnits TypeAlign = Context.getTypeAlignInChars(Ty);
1064 CharUnits ExnObjAlign = Context.getExnObjectAlignment();
1065 if (ExnObjAlign < TypeAlign) {
1066 Diag(ThrowLoc, diag::warn_throw_underaligned_obj);
1067 Diag(ThrowLoc, diag::note_throw_underaligned_obj)
1068 << Ty << (unsigned)TypeAlign.getQuantity()
1069 << (unsigned)ExnObjAlign.getQuantity();
1070 }
1071 }
1072
1073 return false;
1074}
1075
1076static QualType adjustCVQualifiersForCXXThisWithinLambda(
1077 ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
1078 DeclContext *CurSemaContext, ASTContext &ASTCtx) {
1079
1080 QualType ClassType = ThisTy->getPointeeType();
1081 LambdaScopeInfo *CurLSI = nullptr;
1082 DeclContext *CurDC = CurSemaContext;
1083
1084 // Iterate through the stack of lambdas starting from the innermost lambda to
1085 // the outermost lambda, checking if '*this' is ever captured by copy - since
1086 // that could change the cv-qualifiers of the '*this' object.
1087 // The object referred to by '*this' starts out with the cv-qualifiers of its
1088 // member function. We then start with the innermost lambda and iterate
1089 // outward checking to see if any lambda performs a by-copy capture of '*this'
1090 // - and if so, any nested lambda must respect the 'constness' of that
1091 // capturing lamdbda's call operator.
1092 //
1093
1094 // Since the FunctionScopeInfo stack is representative of the lexical
1095 // nesting of the lambda expressions during initial parsing (and is the best
1096 // place for querying information about captures about lambdas that are
1097 // partially processed) and perhaps during instantiation of function templates
1098 // that contain lambda expressions that need to be transformed BUT not
1099 // necessarily during instantiation of a nested generic lambda's function call
1100 // operator (which might even be instantiated at the end of the TU) - at which
1101 // time the DeclContext tree is mature enough to query capture information
1102 // reliably - we use a two pronged approach to walk through all the lexically
1103 // enclosing lambda expressions:
1104 //
1105 // 1) Climb down the FunctionScopeInfo stack as long as each item represents
1106 // a Lambda (i.e. LambdaScopeInfo) AND each LSI's 'closure-type' is lexically
1107 // enclosed by the call-operator of the LSI below it on the stack (while
1108 // tracking the enclosing DC for step 2 if needed). Note the topmost LSI on
1109 // the stack represents the innermost lambda.
1110 //
1111 // 2) If we run out of enclosing LSI's, check if the enclosing DeclContext
1112 // represents a lambda's call operator. If it does, we must be instantiating
1113 // a generic lambda's call operator (represented by the Current LSI, and
1114 // should be the only scenario where an inconsistency between the LSI and the
1115 // DeclContext should occur), so climb out the DeclContexts if they
1116 // represent lambdas, while querying the corresponding closure types
1117 // regarding capture information.
1118
1119 // 1) Climb down the function scope info stack.
1120 for (int I = FunctionScopes.size();
1121 I-- && isa<LambdaScopeInfo>(FunctionScopes[I]) &&
1122 (!CurLSI || !CurLSI->Lambda || CurLSI->Lambda->getDeclContext() ==
1123 cast<LambdaScopeInfo>(FunctionScopes[I])->CallOperator);
1124 CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
1125 CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
1126
1127 if (!CurLSI->isCXXThisCaptured())
1128 continue;
1129
1130 auto C = CurLSI->getCXXThisCapture();
1131
1132 if (C.isCopyCapture()) {
1133 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1134 if (CurLSI->CallOperator->isConst())
1135 ClassType.addConst();
1136 return ASTCtx.getPointerType(ClassType);
1137 }
1138 }
1139
1140 // 2) We've run out of ScopeInfos but check if CurDC is a lambda (which can
1141 // happen during instantiation of its nested generic lambda call operator)
1142 if (isLambdaCallOperator(CurDC)) {
1143 assert(CurLSI && "While computing 'this' capture-type for a generic "(static_cast<void> (0))
1144 "lambda, we must have a corresponding LambdaScopeInfo")(static_cast<void> (0));
1145 assert(isGenericLambdaCallOperatorSpecialization(CurLSI->CallOperator) &&(static_cast<void> (0))
1146 "While computing 'this' capture-type for a generic lambda, when we "(static_cast<void> (0))
1147 "run out of enclosing LSI's, yet the enclosing DC is a "(static_cast<void> (0))
1148 "lambda-call-operator we must be (i.e. Current LSI) in a generic "(static_cast<void> (0))
1149 "lambda call oeprator")(static_cast<void> (0));
1150 assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator))(static_cast<void> (0));
1151
1152 auto IsThisCaptured =
1153 [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
1154 IsConst = false;
1155 IsByCopy = false;
1156 for (auto &&C : Closure->captures()) {
1157 if (C.capturesThis()) {
1158 if (C.getCaptureKind() == LCK_StarThis)
1159 IsByCopy = true;
1160 if (Closure->getLambdaCallOperator()->isConst())
1161 IsConst = true;
1162 return true;
1163 }
1164 }
1165 return false;
1166 };
1167
1168 bool IsByCopyCapture = false;
1169 bool IsConstCapture = false;
1170 CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
1171 while (Closure &&
1172 IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
1173 if (IsByCopyCapture) {
1174 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1175 if (IsConstCapture)
1176 ClassType.addConst();
1177 return ASTCtx.getPointerType(ClassType);
1178 }
1179 Closure = isLambdaCallOperator(Closure->getParent())
1180 ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
1181 : nullptr;
1182 }
1183 }
1184 return ASTCtx.getPointerType(ClassType);
1185}
1186
1187QualType Sema::getCurrentThisType() {
1188 DeclContext *DC = getFunctionLevelDeclContext();
1189 QualType ThisTy = CXXThisTypeOverride;
1190
1191 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
1192 if (method && method->isInstance())
1193 ThisTy = method->getThisType();
1194 }
1195
1196 if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
1197 inTemplateInstantiation() && isa<CXXRecordDecl>(DC)) {
1198
1199 // This is a lambda call operator that is being instantiated as a default
1200 // initializer. DC must point to the enclosing class type, so we can recover
1201 // the 'this' type from it.
1202 QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
1203 // There are no cv-qualifiers for 'this' within default initializers,
1204 // per [expr.prim.general]p4.
1205 ThisTy = Context.getPointerType(ClassTy);
1206 }
1207
1208 // If we are within a lambda's call operator, the cv-qualifiers of 'this'
1209 // might need to be adjusted if the lambda or any of its enclosing lambda's
1210 // captures '*this' by copy.
1211 if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
1212 return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1213 CurContext, Context);
1214 return ThisTy;
1215}
1216
1217Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
1218 Decl *ContextDecl,
1219 Qualifiers CXXThisTypeQuals,
1220 bool Enabled)
1221 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1222{
1223 if (!Enabled || !ContextDecl)
1224 return;
1225
1226 CXXRecordDecl *Record = nullptr;
1227 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1228 Record = Template->getTemplatedDecl();
1229 else
1230 Record = cast<CXXRecordDecl>(ContextDecl);
1231
1232 QualType T = S.Context.getRecordType(Record);
1233 T = S.getASTContext().getQualifiedType(T, CXXThisTypeQuals);
1234
1235 S.CXXThisTypeOverride = S.Context.getPointerType(T);
1236
1237 this->Enabled = true;
1238}
1239
1240
1241Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
1242 if (Enabled) {
1243 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1244 }
1245}
1246
1247static void buildLambdaThisCaptureFixit(Sema &Sema, LambdaScopeInfo *LSI) {
1248 SourceLocation DiagLoc = LSI->IntroducerRange.getEnd();
1249 assert(!LSI->isCXXThisCaptured())(static_cast<void> (0));
1250 // [=, this] {}; // until C++20: Error: this when = is the default
1251 if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval &&
1252 !Sema.getLangOpts().CPlusPlus20)
1253 return;
1254 Sema.Diag(DiagLoc, diag::note_lambda_this_capture_fixit)
1255 << FixItHint::CreateInsertion(
1256 DiagLoc, LSI->NumExplicitCaptures > 0 ? ", this" : "this");
1257}
1258
1259bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1260 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1261 const bool ByCopy) {
1262 // We don't need to capture this in an unevaluated context.
1263 if (isUnevaluatedContext() && !Explicit)
1264 return true;
1265
1266 assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value")(static_cast<void> (0));
1267
1268 const int MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
1269 ? *FunctionScopeIndexToStopAt
1270 : FunctionScopes.size() - 1;
1271
1272 // Check that we can capture the *enclosing object* (referred to by '*this')
1273 // by the capturing-entity/closure (lambda/block/etc) at
1274 // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1275
1276 // Note: The *enclosing object* can only be captured by-value by a
1277 // closure that is a lambda, using the explicit notation:
1278 // [*this] { ... }.
1279 // Every other capture of the *enclosing object* results in its by-reference
1280 // capture.
1281
1282 // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1283 // stack), we can capture the *enclosing object* only if:
1284 // - 'L' has an explicit byref or byval capture of the *enclosing object*
1285 // - or, 'L' has an implicit capture.
1286 // AND
1287 // -- there is no enclosing closure
1288 // -- or, there is some enclosing closure 'E' that has already captured the
1289 // *enclosing object*, and every intervening closure (if any) between 'E'
1290 // and 'L' can implicitly capture the *enclosing object*.
1291 // -- or, every enclosing closure can implicitly capture the
1292 // *enclosing object*
1293
1294
1295 unsigned NumCapturingClosures = 0;
1296 for (int idx = MaxFunctionScopesIndex; idx >= 0; idx--) {
1297 if (CapturingScopeInfo *CSI =
1298 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1299 if (CSI->CXXThisCaptureIndex != 0) {
1300 // 'this' is already being captured; there isn't anything more to do.
1301 CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(BuildAndDiagnose);
1302 break;
1303 }
1304 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1305 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
1306 // This context can't implicitly capture 'this'; fail out.
1307 if (BuildAndDiagnose) {
1308 Diag(Loc, diag::err_this_capture)
1309 << (Explicit && idx == MaxFunctionScopesIndex);
1310 if (!Explicit)
1311 buildLambdaThisCaptureFixit(*this, LSI);
1312 }
1313 return true;
1314 }
1315 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1316 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1317 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1318 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1319 (Explicit && idx == MaxFunctionScopesIndex)) {
1320 // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1321 // iteration through can be an explicit capture, all enclosing closures,
1322 // if any, must perform implicit captures.
1323
1324 // This closure can capture 'this'; continue looking upwards.
1325 NumCapturingClosures++;
1326 continue;
1327 }
1328 // This context can't implicitly capture 'this'; fail out.
1329 if (BuildAndDiagnose)
1330 Diag(Loc, diag::err_this_capture)
1331 << (Explicit && idx == MaxFunctionScopesIndex);
1332
1333 if (!Explicit)
1334 buildLambdaThisCaptureFixit(*this, LSI);
1335 return true;
1336 }
1337 break;
1338 }
1339 if (!BuildAndDiagnose) return false;
1340
1341 // If we got here, then the closure at MaxFunctionScopesIndex on the
1342 // FunctionScopes stack, can capture the *enclosing object*, so capture it
1343 // (including implicit by-reference captures in any enclosing closures).
1344
1345 // In the loop below, respect the ByCopy flag only for the closure requesting
1346 // the capture (i.e. first iteration through the loop below). Ignore it for
1347 // all enclosing closure's up to NumCapturingClosures (since they must be
1348 // implicitly capturing the *enclosing object* by reference (see loop
1349 // above)).
1350 assert((!ByCopy ||(static_cast<void> (0))
1351 dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&(static_cast<void> (0))
1352 "Only a lambda can capture the enclosing object (referred to by "(static_cast<void> (0))
1353 "*this) by copy")(static_cast<void> (0));
1354 QualType ThisTy = getCurrentThisType();
1355 for (int idx = MaxFunctionScopesIndex; NumCapturingClosures;
1356 --idx, --NumCapturingClosures) {
1357 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1358
1359 // The type of the corresponding data member (not a 'this' pointer if 'by
1360 // copy').
1361 QualType CaptureType = ThisTy;
1362 if (ByCopy) {
1363 // If we are capturing the object referred to by '*this' by copy, ignore
1364 // any cv qualifiers inherited from the type of the member function for
1365 // the type of the closure-type's corresponding data member and any use
1366 // of 'this'.
1367 CaptureType = ThisTy->getPointeeType();
1368 CaptureType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1369 }
1370
1371 bool isNested = NumCapturingClosures > 1;
1372 CSI->addThisCapture(isNested, Loc, CaptureType, ByCopy);
1373 }
1374 return false;
1375}
1376
1377ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
1378 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1379 /// is a non-lvalue expression whose value is the address of the object for
1380 /// which the function is called.
1381
1382 QualType ThisTy = getCurrentThisType();
1383 if (ThisTy.isNull())
1384 return Diag(Loc, diag::err_invalid_this_use);
1385 return BuildCXXThisExpr(Loc, ThisTy, /*IsImplicit=*/false);
1386}
1387
1388Expr *Sema::BuildCXXThisExpr(SourceLocation Loc, QualType Type,
1389 bool IsImplicit) {
1390 auto *This = new (Context) CXXThisExpr(Loc, Type, IsImplicit);
1391 MarkThisReferenced(This);
1392 return This;
1393}
1394
1395void Sema::MarkThisReferenced(CXXThisExpr *This) {
1396 CheckCXXThisCapture(This->getExprLoc());
1397}
1398
1399bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
1400 // If we're outside the body of a member function, then we'll have a specified
1401 // type for 'this'.
1402 if (CXXThisTypeOverride.isNull())
1403 return false;
1404
1405 // Determine whether we're looking into a class that's currently being
1406 // defined.
1407 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1408 return Class && Class->isBeingDefined();
1409}
1410
1411/// Parse construction of a specified type.
1412/// Can be interpreted either as function-style casting ("int(x)")
1413/// or class type construction ("ClassType(x,y,z)")
1414/// or creation of a value-initialized type ("int()").
1415ExprResult
1416Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
1417 SourceLocation LParenOrBraceLoc,
1418 MultiExprArg exprs,
1419 SourceLocation RParenOrBraceLoc,
1420 bool ListInitialization) {
1421 if (!TypeRep)
1422 return ExprError();
1423
1424 TypeSourceInfo *TInfo;
1425 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1426 if (!TInfo)
1427 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
1428
1429 auto Result = BuildCXXTypeConstructExpr(TInfo, LParenOrBraceLoc, exprs,
1430 RParenOrBraceLoc, ListInitialization);
1431 // Avoid creating a non-type-dependent expression that contains typos.
1432 // Non-type-dependent expressions are liable to be discarded without
1433 // checking for embedded typos.
1434 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1435 !Result.get()->isTypeDependent())
1436 Result = CorrectDelayedTyposInExpr(Result.get());
1437 else if (Result.isInvalid())
1438 Result = CreateRecoveryExpr(TInfo->getTypeLoc().getBeginLoc(),
1439 RParenOrBraceLoc, exprs, Ty);
1440 return Result;
1441}
1442
1443ExprResult
1444Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1445 SourceLocation LParenOrBraceLoc,
1446 MultiExprArg Exprs,
1447 SourceLocation RParenOrBraceLoc,
1448 bool ListInitialization) {
1449 QualType Ty = TInfo->getType();
1450 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1451
1452 assert((!ListInitialization ||(static_cast<void> (0))
1453 (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) &&(static_cast<void> (0))
1454 "List initialization must have initializer list as expression.")(static_cast<void> (0));
1455 SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc);
1456
1457 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1458 InitializationKind Kind =
1459 Exprs.size()
1460 ? ListInitialization
1461 ? InitializationKind::CreateDirectList(
1462 TyBeginLoc, LParenOrBraceLoc, RParenOrBraceLoc)
1463 : InitializationKind::CreateDirect(TyBeginLoc, LParenOrBraceLoc,
1464 RParenOrBraceLoc)
1465 : InitializationKind::CreateValue(TyBeginLoc, LParenOrBraceLoc,
1466 RParenOrBraceLoc);
1467
1468 // C++1z [expr.type.conv]p1:
1469 // If the type is a placeholder for a deduced class type, [...perform class
1470 // template argument deduction...]
1471 DeducedType *Deduced = Ty->getContainedDeducedType();
1472 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1473 Ty = DeduceTemplateSpecializationFromInitializer(TInfo, Entity,
1474 Kind, Exprs);
1475 if (Ty.isNull())
1476 return ExprError();
1477 Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
1478 }
1479
1480 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1481 // FIXME: CXXUnresolvedConstructExpr does not model list-initialization
1482 // directly. We work around this by dropping the locations of the braces.
1483 SourceRange Locs = ListInitialization
1484 ? SourceRange()
1485 : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1486 return CXXUnresolvedConstructExpr::Create(Context, Ty.getNonReferenceType(),
1487 TInfo, Locs.getBegin(), Exprs,
1488 Locs.getEnd());
1489 }
1490
1491 // C++ [expr.type.conv]p1:
1492 // If the expression list is a parenthesized single expression, the type
1493 // conversion expression is equivalent (in definedness, and if defined in
1494 // meaning) to the corresponding cast expression.
1495 if (Exprs.size() == 1 && !ListInitialization &&
1496 !isa<InitListExpr>(Exprs[0])) {
1497 Expr *Arg = Exprs[0];
1498 return BuildCXXFunctionalCastExpr(TInfo, Ty, LParenOrBraceLoc, Arg,
1499 RParenOrBraceLoc);
1500 }
1501
1502 // For an expression of the form T(), T shall not be an array type.
1503 QualType ElemTy = Ty;
1504 if (Ty->isArrayType()) {
1505 if (!ListInitialization)
1506 return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_array_type)
1507 << FullRange);
1508 ElemTy = Context.getBaseElementType(Ty);
1509 }
1510
1511 // There doesn't seem to be an explicit rule against this but sanity demands
1512 // we only construct objects with object types.
1513 if (Ty->isFunctionType())
1514 return ExprError(Diag(TyBeginLoc, diag::err_init_for_function_type)
1515 << Ty << FullRange);
1516
1517 // C++17 [expr.type.conv]p2:
1518 // If the type is cv void and the initializer is (), the expression is a
1519 // prvalue of the specified type that performs no initialization.
1520 if (!Ty->isVoidType() &&
1521 RequireCompleteType(TyBeginLoc, ElemTy,
1522 diag::err_invalid_incomplete_type_use, FullRange))
1523 return ExprError();
1524
1525 // Otherwise, the expression is a prvalue of the specified type whose
1526 // result object is direct-initialized (11.6) with the initializer.
1527 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1528 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1529
1530 if (Result.isInvalid())
1531 return Result;
1532
1533 Expr *Inner = Result.get();
1534 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1535 Inner = BTE->getSubExpr();
1536 if (!isa<CXXTemporaryObjectExpr>(Inner) &&
1537 !isa<CXXScalarValueInitExpr>(Inner)) {
1538 // If we created a CXXTemporaryObjectExpr, that node also represents the
1539 // functional cast. Otherwise, create an explicit cast to represent
1540 // the syntactic form of a functional-style cast that was used here.
1541 //
1542 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1543 // would give a more consistent AST representation than using a
1544 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1545 // is sometimes handled by initialization and sometimes not.
1546 QualType ResultType = Result.get()->getType();
1547 SourceRange Locs = ListInitialization
1548 ? SourceRange()
1549 : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1550 Result = CXXFunctionalCastExpr::Create(
1551 Context, ResultType, Expr::getValueKindForType(Ty), TInfo, CK_NoOp,
1552 Result.get(), /*Path=*/nullptr, CurFPFeatureOverrides(),
1553 Locs.getBegin(), Locs.getEnd());
1554 }
1555
1556 return Result;
1557}
1558
1559bool Sema::isUsualDeallocationFunction(const CXXMethodDecl *Method) {
1560 // [CUDA] Ignore this function, if we can't call it.
1561 const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext);
1562 if (getLangOpts().CUDA) {
1563 auto CallPreference = IdentifyCUDAPreference(Caller, Method);
1564 // If it's not callable at all, it's not the right function.
1565 if (CallPreference < CFP_WrongSide)
1566 return false;
1567 if (CallPreference == CFP_WrongSide) {
1568 // Maybe. We have to check if there are better alternatives.
1569 DeclContext::lookup_result R =
1570 Method->getDeclContext()->lookup(Method->getDeclName());
1571 for (const auto *D : R) {
1572 if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
1573 if (IdentifyCUDAPreference(Caller, FD) > CFP_WrongSide)
1574 return false;
1575 }
1576 }
1577 // We've found no better variants.
1578 }
1579 }
1580
1581 SmallVector<const FunctionDecl*, 4> PreventedBy;
1582 bool Result = Method->isUsualDeallocationFunction(PreventedBy);
1583
1584 if (Result || !getLangOpts().CUDA || PreventedBy.empty())
1585 return Result;
1586
1587 // In case of CUDA, return true if none of the 1-argument deallocator
1588 // functions are actually callable.
1589 return llvm::none_of(PreventedBy, [&](const FunctionDecl *FD) {
1590 assert(FD->getNumParams() == 1 &&(static_cast<void> (0))
1591 "Only single-operand functions should be in PreventedBy")(static_cast<void> (0));
1592 return IdentifyCUDAPreference(Caller, FD) >= CFP_HostDevice;
1593 });
1594}
1595
1596/// Determine whether the given function is a non-placement
1597/// deallocation function.
1598static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1599 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1600 return S.isUsualDeallocationFunction(Method);
1601
1602 if (FD->getOverloadedOperator() != OO_Delete &&
1603 FD->getOverloadedOperator() != OO_Array_Delete)
1604 return false;
1605
1606 unsigned UsualParams = 1;
1607
1608 if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1609 S.Context.hasSameUnqualifiedType(
1610 FD->getParamDecl(UsualParams)->getType(),
1611 S.Context.getSizeType()))
1612 ++UsualParams;
1613
1614 if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1615 S.Context.hasSameUnqualifiedType(
1616 FD->getParamDecl(UsualParams)->getType(),
1617 S.Context.getTypeDeclType(S.getStdAlignValT())))
1618 ++UsualParams;
1619
1620 return UsualParams == FD->getNumParams();
1621}
1622
1623namespace {
1624 struct UsualDeallocFnInfo {
1625 UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1626 UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1627 : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1628 Destroying(false), HasSizeT(false), HasAlignValT(false),
1629 CUDAPref(Sema::CFP_Native) {
1630 // A function template declaration is never a usual deallocation function.
1631 if (!FD)
1632 return;
1633 unsigned NumBaseParams = 1;
1634 if (FD->isDestroyingOperatorDelete()) {
1635 Destroying = true;
1636 ++NumBaseParams;
1637 }
1638
1639 if (NumBaseParams < FD->getNumParams() &&
1640 S.Context.hasSameUnqualifiedType(
1641 FD->getParamDecl(NumBaseParams)->getType(),
1642 S.Context.getSizeType())) {
1643 ++NumBaseParams;
1644 HasSizeT = true;
1645 }
1646
1647 if (NumBaseParams < FD->getNumParams() &&
1648 FD->getParamDecl(NumBaseParams)->getType()->isAlignValT()) {
1649 ++NumBaseParams;
1650 HasAlignValT = true;
1651 }
1652
1653 // In CUDA, determine how much we'd like / dislike to call this.
1654 if (S.getLangOpts().CUDA)
1655 if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1656 CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1657 }
1658
1659 explicit operator bool() const { return FD; }
1660
1661 bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1662 bool WantAlign) const {
1663 // C++ P0722:
1664 // A destroying operator delete is preferred over a non-destroying
1665 // operator delete.
1666 if (Destroying != Other.Destroying)
1667 return Destroying;
1668
1669 // C++17 [expr.delete]p10:
1670 // If the type has new-extended alignment, a function with a parameter
1671 // of type std::align_val_t is preferred; otherwise a function without
1672 // such a parameter is preferred
1673 if (HasAlignValT != Other.HasAlignValT)
1674 return HasAlignValT == WantAlign;
1675
1676 if (HasSizeT != Other.HasSizeT)
1677 return HasSizeT == WantSize;
1678
1679 // Use CUDA call preference as a tiebreaker.
1680 return CUDAPref > Other.CUDAPref;
1681 }
1682
1683 DeclAccessPair Found;
1684 FunctionDecl *FD;
1685 bool Destroying, HasSizeT, HasAlignValT;
1686 Sema::CUDAFunctionPreference CUDAPref;
1687 };
1688}
1689
1690/// Determine whether a type has new-extended alignment. This may be called when
1691/// the type is incomplete (for a delete-expression with an incomplete pointee
1692/// type), in which case it will conservatively return false if the alignment is
1693/// not known.
1694static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1695 return S.getLangOpts().AlignedAllocation &&
1696 S.getASTContext().getTypeAlignIfKnown(AllocType) >
1697 S.getASTContext().getTargetInfo().getNewAlign();
1698}
1699
1700/// Select the correct "usual" deallocation function to use from a selection of
1701/// deallocation functions (either global or class-scope).
1702static UsualDeallocFnInfo resolveDeallocationOverload(
1703 Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1704 llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1705 UsualDeallocFnInfo Best;
1706
1707 for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1708 UsualDeallocFnInfo Info(S, I.getPair());
1709 if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1710 Info.CUDAPref == Sema::CFP_Never)
1711 continue;
1712
1713 if (!Best) {
1714 Best = Info;
1715 if (BestFns)
1716 BestFns->push_back(Info);
1717 continue;
1718 }
1719
1720 if (Best.isBetterThan(Info, WantSize, WantAlign))
1721 continue;
1722
1723 // If more than one preferred function is found, all non-preferred
1724 // functions are eliminated from further consideration.
1725 if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1726 BestFns->clear();
1727
1728 Best = Info;
1729 if (BestFns)
1730 BestFns->push_back(Info);
1731 }
1732
1733 return Best;
1734}
1735
1736/// Determine whether a given type is a class for which 'delete[]' would call
1737/// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1738/// we need to store the array size (even if the type is
1739/// trivially-destructible).
1740static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1741 QualType allocType) {
1742 const RecordType *record =
1743 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1744 if (!record) return false;
1745
1746 // Try to find an operator delete[] in class scope.
1747
1748 DeclarationName deleteName =
1749 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1750 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1751 S.LookupQualifiedName(ops, record->getDecl());
1752
1753 // We're just doing this for information.
1754 ops.suppressDiagnostics();
1755
1756 // Very likely: there's no operator delete[].
1757 if (ops.empty()) return false;
1758
1759 // If it's ambiguous, it should be illegal to call operator delete[]
1760 // on this thing, so it doesn't matter if we allocate extra space or not.
1761 if (ops.isAmbiguous()) return false;
1762
1763 // C++17 [expr.delete]p10:
1764 // If the deallocation functions have class scope, the one without a
1765 // parameter of type std::size_t is selected.
1766 auto Best = resolveDeallocationOverload(
1767 S, ops, /*WantSize*/false,
1768 /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1769 return Best && Best.HasSizeT;
1770}
1771
1772/// Parsed a C++ 'new' expression (C++ 5.3.4).
1773///
1774/// E.g.:
1775/// @code new (memory) int[size][4] @endcode
1776/// or
1777/// @code ::new Foo(23, "hello") @endcode
1778///
1779/// \param StartLoc The first location of the expression.
1780/// \param UseGlobal True if 'new' was prefixed with '::'.
1781/// \param PlacementLParen Opening paren of the placement arguments.
1782/// \param PlacementArgs Placement new arguments.
1783/// \param PlacementRParen Closing paren of the placement arguments.
1784/// \param TypeIdParens If the type is in parens, the source range.
1785/// \param D The type to be allocated, as well as array dimensions.
1786/// \param Initializer The initializing expression or initializer-list, or null
1787/// if there is none.
1788ExprResult
1789Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1790 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1791 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1792 Declarator &D, Expr *Initializer) {
1793 Optional<Expr *> ArraySize;
1794 // If the specified type is an array, unwrap it and save the expression.
1795 if (D.getNumTypeObjects() > 0 &&
1796 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1797 DeclaratorChunk &Chunk = D.getTypeObject(0);
1798 if (D.getDeclSpec().hasAutoTypeSpec())
1799 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1800 << D.getSourceRange());
1801 if (Chunk.Arr.hasStatic)
1802 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1803 << D.getSourceRange());
1804 if (!Chunk.Arr.NumElts && !Initializer)
1805 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1806 << D.getSourceRange());
1807
1808 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1809 D.DropFirstTypeObject();
1810 }
1811
1812 // Every dimension shall be of constant size.
1813 if (ArraySize) {
1814 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1815 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1816 break;
1817
1818 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1819 if (Expr *NumElts = (Expr *)Array.NumElts) {
1820 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1821 // FIXME: GCC permits constant folding here. We should either do so consistently
1822 // or not do so at all, rather than changing behavior in C++14 onwards.
1823 if (getLangOpts().CPlusPlus14) {
1824 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1825 // shall be a converted constant expression (5.19) of type std::size_t
1826 // and shall evaluate to a strictly positive value.
1827 llvm::APSInt Value(Context.getIntWidth(Context.getSizeType()));
1828 Array.NumElts
1829 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1830 CCEK_ArrayBound)
1831 .get();
1832 } else {
1833 Array.NumElts =
1834 VerifyIntegerConstantExpression(
1835 NumElts, nullptr, diag::err_new_array_nonconst, AllowFold)
1836 .get();
1837 }
1838 if (!Array.NumElts)
1839 return ExprError();
1840 }
1841 }
1842 }
1843 }
1844
1845 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1846 QualType AllocType = TInfo->getType();
1847 if (D.isInvalidType())
1848 return ExprError();
1849
1850 SourceRange DirectInitRange;
1851 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1852 DirectInitRange = List->getSourceRange();
1853
1854 return BuildCXXNew(SourceRange(StartLoc, D.getEndLoc()), UseGlobal,
1855 PlacementLParen, PlacementArgs, PlacementRParen,
1856 TypeIdParens, AllocType, TInfo, ArraySize, DirectInitRange,
1857 Initializer);
1858}
1859
1860static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1861 Expr *Init) {
1862 if (!Init)
1863 return true;
1864 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1865 return PLE->getNumExprs() == 0;
1866 if (isa<ImplicitValueInitExpr>(Init))
1867 return true;
1868 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1869 return !CCE->isListInitialization() &&
1870 CCE->getConstructor()->isDefaultConstructor();
1871 else if (Style == CXXNewExpr::ListInit) {
1872 assert(isa<InitListExpr>(Init) &&(static_cast<void> (0))
1873 "Shouldn't create list CXXConstructExprs for arrays.")(static_cast<void> (0));
1874 return true;
1875 }
1876 return false;
1877}
1878
1879bool
1880Sema::isUnavailableAlignedAllocationFunction(const FunctionDecl &FD) const {
1881 if (!getLangOpts().AlignedAllocationUnavailable)
1882 return false;
1883 if (FD.isDefined())
1884 return false;
1885 Optional<unsigned> AlignmentParam;
1886 if (FD.isReplaceableGlobalAllocationFunction(&AlignmentParam) &&
1887 AlignmentParam.hasValue())
1888 return true;
1889 return false;
1890}
1891
1892// Emit a diagnostic if an aligned allocation/deallocation function that is not
1893// implemented in the standard library is selected.
1894void Sema::diagnoseUnavailableAlignedAllocation(const FunctionDecl &FD,
1895 SourceLocation Loc) {
1896 if (isUnavailableAlignedAllocationFunction(FD)) {
1897 const llvm::Triple &T = getASTContext().getTargetInfo().getTriple();
1898 StringRef OSName = AvailabilityAttr::getPlatformNameSourceSpelling(
1899 getASTContext().getTargetInfo().getPlatformName());
1900 VersionTuple OSVersion = alignedAllocMinVersion(T.getOS());
1901
1902 OverloadedOperatorKind Kind = FD.getDeclName().getCXXOverloadedOperator();
1903 bool IsDelete = Kind == OO_Delete || Kind == OO_Array_Delete;
1904 Diag(Loc, diag::err_aligned_allocation_unavailable)
1905 << IsDelete << FD.getType().getAsString() << OSName
1906 << OSVersion.getAsString() << OSVersion.empty();
1907 Diag(Loc, diag::note_silence_aligned_allocation_unavailable);
1908 }
1909}
1910
1911ExprResult
1912Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1913 SourceLocation PlacementLParen,
1914 MultiExprArg PlacementArgs,
1915 SourceLocation PlacementRParen,
1916 SourceRange TypeIdParens,
1917 QualType AllocType,
1918 TypeSourceInfo *AllocTypeInfo,
1919 Optional<Expr *> ArraySize,
1920 SourceRange DirectInitRange,
1921 Expr *Initializer) {
1922 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1923 SourceLocation StartLoc = Range.getBegin();
1924
1925 CXXNewExpr::InitializationStyle initStyle;
1926 if (DirectInitRange.isValid()) {
1927 assert(Initializer && "Have parens but no initializer.")(static_cast<void> (0));
1928 initStyle = CXXNewExpr::CallInit;
1929 } else if (Initializer && isa<InitListExpr>(Initializer))
1930 initStyle = CXXNewExpr::ListInit;
1931 else {
1932 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||(static_cast<void> (0))
1933 isa<CXXConstructExpr>(Initializer)) &&(static_cast<void> (0))
1934 "Initializer expression that cannot have been implicitly created.")(static_cast<void> (0));
1935 initStyle = CXXNewExpr::NoInit;
1936 }
1937
1938 Expr **Inits = &Initializer;
1939 unsigned NumInits = Initializer ? 1 : 0;
1940 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1941 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init")(static_cast<void> (0));
1942 Inits = List->getExprs();
1943 NumInits = List->getNumExprs();
1944 }
1945
1946 // C++11 [expr.new]p15:
1947 // A new-expression that creates an object of type T initializes that
1948 // object as follows:
1949 InitializationKind Kind
1950 // - If the new-initializer is omitted, the object is default-
1951 // initialized (8.5); if no initialization is performed,
1952 // the object has indeterminate value
1953 = initStyle == CXXNewExpr::NoInit
1954 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1955 // - Otherwise, the new-initializer is interpreted according to
1956 // the
1957 // initialization rules of 8.5 for direct-initialization.
1958 : initStyle == CXXNewExpr::ListInit
1959 ? InitializationKind::CreateDirectList(
1960 TypeRange.getBegin(), Initializer->getBeginLoc(),
1961 Initializer->getEndLoc())
1962 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1963 DirectInitRange.getBegin(),
1964 DirectInitRange.getEnd());
1965
1966 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1967 auto *Deduced = AllocType->getContainedDeducedType();
1968 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1969 if (ArraySize)
1970 return ExprError(
1971 Diag(ArraySize ? (*ArraySize)->getExprLoc() : TypeRange.getBegin(),
1972 diag::err_deduced_class_template_compound_type)
1973 << /*array*/ 2
1974 << (ArraySize ? (*ArraySize)->getSourceRange() : TypeRange));
1975
1976 InitializedEntity Entity
1977 = InitializedEntity::InitializeNew(StartLoc, AllocType);
1978 AllocType = DeduceTemplateSpecializationFromInitializer(
1979 AllocTypeInfo, Entity, Kind, MultiExprArg(Inits, NumInits));
1980 if (AllocType.isNull())
1981 return ExprError();
1982 } else if (Deduced) {
1983 bool Braced = (initStyle == CXXNewExpr::ListInit);
1984 if (NumInits == 1) {
1985 if (auto p = dyn_cast_or_null<InitListExpr>(Inits[0])) {
1986 Inits = p->getInits();
1987 NumInits = p->getNumInits();
1988 Braced = true;
1989 }
1990 }
1991
1992 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1993 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1994 << AllocType << TypeRange);
1995 if (NumInits > 1) {
1996 Expr *FirstBad = Inits[1];
1997 return ExprError(Diag(FirstBad->getBeginLoc(),
1998 diag::err_auto_new_ctor_multiple_expressions)
1999 << AllocType << TypeRange);
2000 }
2001 if (Braced && !getLangOpts().CPlusPlus17)
2002 Diag(Initializer->getBeginLoc(), diag::ext_auto_new_list_init)
2003 << AllocType << TypeRange;
2004 Expr *Deduce = Inits[0];
2005 QualType DeducedType;
2006 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
2007 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
2008 << AllocType << Deduce->getType()
2009 << TypeRange << Deduce->getSourceRange());
2010 if (DeducedType.isNull())
2011 return ExprError();
2012 AllocType = DeducedType;
2013 }
2014
2015 // Per C++0x [expr.new]p5, the type being constructed may be a
2016 // typedef of an array type.
2017 if (!ArraySize) {
2018 if (const ConstantArrayType *Array
2019 = Context.getAsConstantArrayType(AllocType)) {
2020 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
2021 Context.getSizeType(),
2022 TypeRange.getEnd());
2023 AllocType = Array->getElementType();
2024 }
2025 }
2026
2027 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
2028 return ExprError();
2029
2030 // In ARC, infer 'retaining' for the allocated
2031 if (getLangOpts().ObjCAutoRefCount &&
2032 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2033 AllocType->isObjCLifetimeType()) {
2034 AllocType = Context.getLifetimeQualifiedType(AllocType,
2035 AllocType->getObjCARCImplicitLifetime());
2036 }
2037
2038 QualType ResultType = Context.getPointerType(AllocType);
2039
2040 if (ArraySize && *ArraySize &&
2041 (*ArraySize)->getType()->isNonOverloadPlaceholderType()) {
2042 ExprResult result = CheckPlaceholderExpr(*ArraySize);
2043 if (result.isInvalid()) return ExprError();
2044 ArraySize = result.get();
2045 }
2046 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
2047 // integral or enumeration type with a non-negative value."
2048 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
2049 // enumeration type, or a class type for which a single non-explicit
2050 // conversion function to integral or unscoped enumeration type exists.
2051 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
2052 // std::size_t.
2053 llvm::Optional<uint64_t> KnownArraySize;
2054 if (ArraySize && *ArraySize && !(*ArraySize)->isTypeDependent()) {
2055 ExprResult ConvertedSize;
2056 if (getLangOpts().CPlusPlus14) {
2057 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?")(static_cast<void> (0));
2058
2059 ConvertedSize = PerformImplicitConversion(*ArraySize, Context.getSizeType(),
2060 AA_Converting);
2061
2062 if (!ConvertedSize.isInvalid() &&
2063 (*ArraySize)->getType()->getAs<RecordType>())
2064 // Diagnose the compatibility of this conversion.
2065 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
2066 << (*ArraySize)->getType() << 0 << "'size_t'";
2067 } else {
2068 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
2069 protected:
2070 Expr *ArraySize;
2071
2072 public:
2073 SizeConvertDiagnoser(Expr *ArraySize)
2074 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
2075 ArraySize(ArraySize) {}
2076
2077 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
2078 QualType T) override {
2079 return S.Diag(Loc, diag::err_array_size_not_integral)
2080 << S.getLangOpts().CPlusPlus11 << T;
2081 }
2082
2083 SemaDiagnosticBuilder diagnoseIncomplete(
2084 Sema &S, SourceLocation Loc, QualType T) override {
2085 return S.Diag(Loc, diag::err_array_size_incomplete_type)
2086 << T << ArraySize->getSourceRange();
2087 }
2088
2089 SemaDiagnosticBuilder diagnoseExplicitConv(
2090 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
2091 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
2092 }
2093
2094 SemaDiagnosticBuilder noteExplicitConv(
2095 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2096 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
2097 << ConvTy->isEnumeralType() << ConvTy;
2098 }
2099
2100 SemaDiagnosticBuilder diagnoseAmbiguous(
2101 Sema &S, SourceLocation Loc, QualType T) override {
2102 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
2103 }
2104
2105 SemaDiagnosticBuilder noteAmbiguous(
2106 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2107 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
2108 << ConvTy->isEnumeralType() << ConvTy;
2109 }
2110
2111 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2112 QualType T,
2113 QualType ConvTy) override {
2114 return S.Diag(Loc,
2115 S.getLangOpts().CPlusPlus11
2116 ? diag::warn_cxx98_compat_array_size_conversion
2117 : diag::ext_array_size_conversion)
2118 << T << ConvTy->isEnumeralType() << ConvTy;
2119 }
2120 } SizeDiagnoser(*ArraySize);
2121
2122 ConvertedSize = PerformContextualImplicitConversion(StartLoc, *ArraySize,
2123 SizeDiagnoser);
2124 }
2125 if (ConvertedSize.isInvalid())
2126 return ExprError();
2127
2128 ArraySize = ConvertedSize.get();
2129 QualType SizeType = (*ArraySize)->getType();
2130
2131 if (!SizeType->isIntegralOrUnscopedEnumerationType())
2132 return ExprError();
2133
2134 // C++98 [expr.new]p7:
2135 // The expression in a direct-new-declarator shall have integral type
2136 // with a non-negative value.
2137 //
2138 // Let's see if this is a constant < 0. If so, we reject it out of hand,
2139 // per CWG1464. Otherwise, if it's not a constant, we must have an
2140 // unparenthesized array type.
2141 if (!(*ArraySize)->isValueDependent()) {
2142 // We've already performed any required implicit conversion to integer or
2143 // unscoped enumeration type.
2144 // FIXME: Per CWG1464, we are required to check the value prior to
2145 // converting to size_t. This will never find a negative array size in
2146 // C++14 onwards, because Value is always unsigned here!
2147 if (Optional<llvm::APSInt> Value =
2148 (*ArraySize)->getIntegerConstantExpr(Context)) {
2149 if (Value->isSigned() && Value->isNegative()) {
2150 return ExprError(Diag((*ArraySize)->getBeginLoc(),
2151 diag::err_typecheck_negative_array_size)
2152 << (*ArraySize)->getSourceRange());
2153 }
2154
2155 if (!AllocType->isDependentType()) {
2156 unsigned ActiveSizeBits = ConstantArrayType::getNumAddressingBits(
2157 Context, AllocType, *Value);
2158 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
2159 return ExprError(
2160 Diag((*ArraySize)->getBeginLoc(), diag::err_array_too_large)
2161 << toString(*Value, 10) << (*ArraySize)->getSourceRange());
2162 }
2163
2164 KnownArraySize = Value->getZExtValue();
2165 } else if (TypeIdParens.isValid()) {
2166 // Can't have dynamic array size when the type-id is in parentheses.
2167 Diag((*ArraySize)->getBeginLoc(), diag::ext_new_paren_array_nonconst)
2168 << (*ArraySize)->getSourceRange()
2169 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
2170 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
2171
2172 TypeIdParens = SourceRange();
2173 }
2174 }
2175
2176 // Note that we do *not* convert the argument in any way. It can
2177 // be signed, larger than size_t, whatever.
2178 }
2179
2180 FunctionDecl *OperatorNew = nullptr;
2181 FunctionDecl *OperatorDelete = nullptr;
2182 unsigned Alignment =
2183 AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
2184 unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
2185 bool PassAlignment = getLangOpts().AlignedAllocation &&
2186 Alignment > NewAlignment;
2187
2188 AllocationFunctionScope Scope = UseGlobal ? AFS_Global : AFS_Both;
2189 if (!AllocType->isDependentType() &&
2190 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
2191 FindAllocationFunctions(
2192 StartLoc, SourceRange(PlacementLParen, PlacementRParen), Scope, Scope,
2193 AllocType, ArraySize.hasValue(), PassAlignment, PlacementArgs,
2194 OperatorNew, OperatorDelete))
2195 return ExprError();
2196
2197 // If this is an array allocation, compute whether the usual array
2198 // deallocation function for the type has a size_t parameter.
2199 bool UsualArrayDeleteWantsSize = false;
2200 if (ArraySize && !AllocType->isDependentType())
2201 UsualArrayDeleteWantsSize =
2202 doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
2203
2204 SmallVector<Expr *, 8> AllPlaceArgs;
2205 if (OperatorNew) {
2206 auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2207 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
2208 : VariadicDoesNotApply;
2209
2210 // We've already converted the placement args, just fill in any default
2211 // arguments. Skip the first parameter because we don't have a corresponding
2212 // argument. Skip the second parameter too if we're passing in the
2213 // alignment; we've already filled it in.
2214 unsigned NumImplicitArgs = PassAlignment ? 2 : 1;
2215 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
2216 NumImplicitArgs, PlacementArgs, AllPlaceArgs,
2217 CallType))
2218 return ExprError();
2219
2220 if (!AllPlaceArgs.empty())
2221 PlacementArgs = AllPlaceArgs;
2222
2223 // We would like to perform some checking on the given `operator new` call,
2224 // but the PlacementArgs does not contain the implicit arguments,
2225 // namely allocation size and maybe allocation alignment,
2226 // so we need to conjure them.
2227
2228 QualType SizeTy = Context.getSizeType();
2229 unsigned SizeTyWidth = Context.getTypeSize(SizeTy);
2230
2231 llvm::APInt SingleEltSize(
2232 SizeTyWidth, Context.getTypeSizeInChars(AllocType).getQuantity());
2233
2234 // How many bytes do we want to allocate here?
2235 llvm::Optional<llvm::APInt> AllocationSize;
2236 if (!ArraySize.hasValue() && !AllocType->isDependentType()) {
2237 // For non-array operator new, we only want to allocate one element.
2238 AllocationSize = SingleEltSize;
2239 } else if (KnownArraySize.hasValue() && !AllocType->isDependentType()) {
2240 // For array operator new, only deal with static array size case.
2241 bool Overflow;
2242 AllocationSize = llvm::APInt(SizeTyWidth, *KnownArraySize)
2243 .umul_ov(SingleEltSize, Overflow);
2244 (void)Overflow;
2245 assert((static_cast<void> (0))
2246 !Overflow &&(static_cast<void> (0))
2247 "Expected that all the overflows would have been handled already.")(static_cast<void> (0));
2248 }
2249
2250 IntegerLiteral AllocationSizeLiteral(
2251 Context,
2252 AllocationSize.getValueOr(llvm::APInt::getNullValue(SizeTyWidth)),
2253 SizeTy, SourceLocation());
2254 // Otherwise, if we failed to constant-fold the allocation size, we'll
2255 // just give up and pass-in something opaque, that isn't a null pointer.
2256 OpaqueValueExpr OpaqueAllocationSize(SourceLocation(), SizeTy, VK_PRValue,
2257 OK_Ordinary, /*SourceExpr=*/nullptr);
2258
2259 // Let's synthesize the alignment argument in case we will need it.
2260 // Since we *really* want to allocate these on stack, this is slightly ugly
2261 // because there might not be a `std::align_val_t` type.
2262 EnumDecl *StdAlignValT = getStdAlignValT();
2263 QualType AlignValT =
2264 StdAlignValT ? Context.getTypeDeclType(StdAlignValT) : SizeTy;
2265 IntegerLiteral AlignmentLiteral(
2266 Context,
2267 llvm::APInt(Context.getTypeSize(SizeTy),
2268 Alignment / Context.getCharWidth()),
2269 SizeTy, SourceLocation());
2270 ImplicitCastExpr DesiredAlignment(ImplicitCastExpr::OnStack, AlignValT,
2271 CK_IntegralCast, &AlignmentLiteral,
2272 VK_PRValue, FPOptionsOverride());
2273
2274 // Adjust placement args by prepending conjured size and alignment exprs.
2275 llvm::SmallVector<Expr *, 8> CallArgs;
2276 CallArgs.reserve(NumImplicitArgs + PlacementArgs.size());
2277 CallArgs.emplace_back(AllocationSize.hasValue()
2278 ? static_cast<Expr *>(&AllocationSizeLiteral)
2279 : &OpaqueAllocationSize);
2280 if (PassAlignment)
2281 CallArgs.emplace_back(&DesiredAlignment);
2282 CallArgs.insert(CallArgs.end(), PlacementArgs.begin(), PlacementArgs.end());
2283
2284 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, CallArgs);
2285
2286 checkCall(OperatorNew, Proto, /*ThisArg=*/nullptr, CallArgs,
2287 /*IsMemberFunction=*/false, StartLoc, Range, CallType);
2288
2289 // Warn if the type is over-aligned and is being allocated by (unaligned)
2290 // global operator new.
2291 if (PlacementArgs.empty() && !PassAlignment &&
2292 (OperatorNew->isImplicit() ||
2293 (OperatorNew->getBeginLoc().isValid() &&
2294 getSourceManager().isInSystemHeader(OperatorNew->getBeginLoc())))) {
2295 if (Alignment > NewAlignment)
2296 Diag(StartLoc, diag::warn_overaligned_type)
2297 << AllocType
2298 << unsigned(Alignment / Context.getCharWidth())
2299 << unsigned(NewAlignment / Context.getCharWidth());
2300 }
2301 }
2302
2303 // Array 'new' can't have any initializers except empty parentheses.
2304 // Initializer lists are also allowed, in C++11. Rely on the parser for the
2305 // dialect distinction.
2306 if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
2307 SourceRange InitRange(Inits[0]->getBeginLoc(),
2308 Inits[NumInits - 1]->getEndLoc());
2309 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
2310 return ExprError();
2311 }
2312
2313 // If we can perform the initialization, and we've not already done so,
2314 // do it now.
2315 if (!AllocType->isDependentType() &&
2316 !Expr::hasAnyTypeDependentArguments(
2317 llvm::makeArrayRef(Inits, NumInits))) {
2318 // The type we initialize is the complete type, including the array bound.
2319 QualType InitType;
2320 if (KnownArraySize)
2321 InitType = Context.getConstantArrayType(
2322 AllocType,
2323 llvm::APInt(Context.getTypeSize(Context.getSizeType()),
2324 *KnownArraySize),
2325 *ArraySize, ArrayType::Normal, 0);
2326 else if (ArraySize)
2327 InitType =
2328 Context.getIncompleteArrayType(AllocType, ArrayType::Normal, 0);
2329 else
2330 InitType = AllocType;
2331
2332 InitializedEntity Entity
2333 = InitializedEntity::InitializeNew(StartLoc, InitType);
2334 InitializationSequence InitSeq(*this, Entity, Kind,
2335 MultiExprArg(Inits, NumInits));
2336 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
2337 MultiExprArg(Inits, NumInits));
2338 if (FullInit.isInvalid())
2339 return ExprError();
2340
2341 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
2342 // we don't want the initialized object to be destructed.
2343 // FIXME: We should not create these in the first place.
2344 if (CXXBindTemporaryExpr *Binder =
2345 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
2346 FullInit = Binder->getSubExpr();
2347
2348 Initializer = FullInit.get();
2349
2350 // FIXME: If we have a KnownArraySize, check that the array bound of the
2351 // initializer is no greater than that constant value.
2352
2353 if (ArraySize && !*ArraySize) {
2354 auto *CAT = Context.getAsConstantArrayType(Initializer->getType());
2355 if (CAT) {
2356 // FIXME: Track that the array size was inferred rather than explicitly
2357 // specified.
2358 ArraySize = IntegerLiteral::Create(
2359 Context, CAT->getSize(), Context.getSizeType(), TypeRange.getEnd());
2360 } else {
2361 Diag(TypeRange.getEnd(), diag::err_new_array_size_unknown_from_init)
2362 << Initializer->getSourceRange();
2363 }
2364 }
2365 }
2366
2367 // Mark the new and delete operators as referenced.
2368 if (OperatorNew) {
2369 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
2370 return ExprError();
2371 MarkFunctionReferenced(StartLoc, OperatorNew);
2372 }
2373 if (OperatorDelete) {
2374 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
2375 return ExprError();
2376 MarkFunctionReferenced(StartLoc, OperatorDelete);
2377 }
2378
2379 return CXXNewExpr::Create(Context, UseGlobal, OperatorNew, OperatorDelete,
2380 PassAlignment, UsualArrayDeleteWantsSize,
2381 PlacementArgs, TypeIdParens, ArraySize, initStyle,
2382 Initializer, ResultType, AllocTypeInfo, Range,
2383 DirectInitRange);
2384}
2385
2386/// Checks that a type is suitable as the allocated type
2387/// in a new-expression.
2388bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
2389 SourceRange R) {
2390 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2391 // abstract class type or array thereof.
2392 if (AllocType->isFunctionType())
2393 return Diag(Loc, diag::err_bad_new_type)
2394 << AllocType << 0 << R;
2395 else if (AllocType->isReferenceType())
2396 return Diag(Loc, diag::err_bad_new_type)
2397 << AllocType << 1 << R;
2398 else if (!AllocType->isDependentType() &&
2399 RequireCompleteSizedType(
2400 Loc, AllocType, diag::err_new_incomplete_or_sizeless_type, R))
2401 return true;
2402 else if (RequireNonAbstractType(Loc, AllocType,
2403 diag::err_allocation_of_abstract_type))
2404 return true;
2405 else if (AllocType->isVariablyModifiedType())
2406 return Diag(Loc, diag::err_variably_modified_new_type)
2407 << AllocType;
2408 else if (AllocType.getAddressSpace() != LangAS::Default &&
2409 !getLangOpts().OpenCLCPlusPlus)
2410 return Diag(Loc, diag::err_address_space_qualified_new)
2411 << AllocType.getUnqualifiedType()
2412 << AllocType.getQualifiers().getAddressSpaceAttributePrintValue();
2413 else if (getLangOpts().ObjCAutoRefCount) {
2414 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2415 QualType BaseAllocType = Context.getBaseElementType(AT);
2416 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2417 BaseAllocType->isObjCLifetimeType())
2418 return Diag(Loc, diag::err_arc_new_array_without_ownership)
2419 << BaseAllocType;
2420 }
2421 }
2422
2423 return false;
2424}
2425
2426static bool resolveAllocationOverload(
2427 Sema &S, LookupResult &R, SourceRange Range, SmallVectorImpl<Expr *> &Args,
2428 bool &PassAlignment, FunctionDecl *&Operator,
2429 OverloadCandidateSet *AlignedCandidates, Expr *AlignArg, bool Diagnose) {
2430 OverloadCandidateSet Candidates(R.getNameLoc(),
2431 OverloadCandidateSet::CSK_Normal);
2432 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2433 Alloc != AllocEnd; ++Alloc) {
2434 // Even member operator new/delete are implicitly treated as
2435 // static, so don't use AddMemberCandidate.
2436 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2437
2438 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2439 S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2440 /*ExplicitTemplateArgs=*/nullptr, Args,
2441 Candidates,
2442 /*SuppressUserConversions=*/false);
2443 continue;
2444 }
2445
2446 FunctionDecl *Fn = cast<FunctionDecl>(D);
2447 S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2448 /*SuppressUserConversions=*/false);
2449 }
2450
2451 // Do the resolution.
2452 OverloadCandidateSet::iterator Best;
2453 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2454 case OR_Success: {
2455 // Got one!
2456 FunctionDecl *FnDecl = Best->Function;
2457 if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2458 Best->FoundDecl) == Sema::AR_inaccessible)
2459 return true;
2460
2461 Operator = FnDecl;
2462 return false;
2463 }
2464
2465 case OR_No_Viable_Function:
2466 // C++17 [expr.new]p13:
2467 // If no matching function is found and the allocated object type has
2468 // new-extended alignment, the alignment argument is removed from the
2469 // argument list, and overload resolution is performed again.
2470 if (PassAlignment) {
2471 PassAlignment = false;
2472 AlignArg = Args[1];
2473 Args.erase(Args.begin() + 1);
2474 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2475 Operator, &Candidates, AlignArg,
2476 Diagnose);
2477 }
2478
2479 // MSVC will fall back on trying to find a matching global operator new
2480 // if operator new[] cannot be found. Also, MSVC will leak by not
2481 // generating a call to operator delete or operator delete[], but we
2482 // will not replicate that bug.
2483 // FIXME: Find out how this interacts with the std::align_val_t fallback
2484 // once MSVC implements it.
2485 if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2486 S.Context.getLangOpts().MSVCCompat) {
2487 R.clear();
2488 R.setLookupName(S.Context.DeclarationNames.getCXXOperatorName(OO_New));
2489 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
2490 // FIXME: This will give bad diagnostics pointing at the wrong functions.
2491 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2492 Operator, /*Candidates=*/nullptr,
2493 /*AlignArg=*/nullptr, Diagnose);
2494 }
2495
2496 if (Diagnose) {
2497 // If this is an allocation of the form 'new (p) X' for some object
2498 // pointer p (or an expression that will decay to such a pointer),
2499 // diagnose the missing inclusion of <new>.
2500 if (!R.isClassLookup() && Args.size() == 2 &&
2501 (Args[1]->getType()->isObjectPointerType() ||
2502 Args[1]->getType()->isArrayType())) {
2503 S.Diag(R.getNameLoc(), diag::err_need_header_before_placement_new)
2504 << R.getLookupName() << Range;
2505 // Listing the candidates is unlikely to be useful; skip it.
2506 return true;
2507 }
2508
2509 // Finish checking all candidates before we note any. This checking can
2510 // produce additional diagnostics so can't be interleaved with our
2511 // emission of notes.
2512 //
2513 // For an aligned allocation, separately check the aligned and unaligned
2514 // candidates with their respective argument lists.
2515 SmallVector<OverloadCandidate*, 32> Cands;
2516 SmallVector<OverloadCandidate*, 32> AlignedCands;
2517 llvm::SmallVector<Expr*, 4> AlignedArgs;
2518 if (AlignedCandidates) {
2519 auto IsAligned = [](OverloadCandidate &C) {
2520 return C.Function->getNumParams() > 1 &&
2521 C.Function->getParamDecl(1)->getType()->isAlignValT();
2522 };
2523 auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2524
2525 AlignedArgs.reserve(Args.size() + 1);
2526 AlignedArgs.push_back(Args[0]);
2527 AlignedArgs.push_back(AlignArg);
2528 AlignedArgs.append(Args.begin() + 1, Args.end());
2529 AlignedCands = AlignedCandidates->CompleteCandidates(
2530 S, OCD_AllCandidates, AlignedArgs, R.getNameLoc(), IsAligned);
2531
2532 Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args,
2533 R.getNameLoc(), IsUnaligned);
2534 } else {
2535 Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args,
2536 R.getNameLoc());
2537 }
2538
2539 S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
2540 << R.getLookupName() << Range;
2541 if (AlignedCandidates)
2542 AlignedCandidates->NoteCandidates(S, AlignedArgs, AlignedCands, "",
2543 R.getNameLoc());
2544 Candidates.NoteCandidates(S, Args, Cands, "", R.getNameLoc());
2545 }
2546 return true;
2547
2548 case OR_Ambiguous:
2549 if (Diagnose) {
2550 Candidates.NoteCandidates(
2551 PartialDiagnosticAt(R.getNameLoc(),
2552 S.PDiag(diag::err_ovl_ambiguous_call)
2553 << R.getLookupName() << Range),
2554 S, OCD_AmbiguousCandidates, Args);
2555 }
2556 return true;
2557
2558 case OR_Deleted: {
2559 if (Diagnose) {
2560 Candidates.NoteCandidates(
2561 PartialDiagnosticAt(R.getNameLoc(),
2562 S.PDiag(diag::err_ovl_deleted_call)
2563 << R.getLookupName() << Range),
2564 S, OCD_AllCandidates, Args);
2565 }
2566 return true;
2567 }
2568 }
2569 llvm_unreachable("Unreachable, bad result from BestViableFunction")__builtin_unreachable();
2570}
2571
2572bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
2573 AllocationFunctionScope NewScope,
2574 AllocationFunctionScope DeleteScope,
2575 QualType AllocType, bool IsArray,
2576 bool &PassAlignment, MultiExprArg PlaceArgs,
2577 FunctionDecl *&OperatorNew,
2578 FunctionDecl *&OperatorDelete,
2579 bool Diagnose) {
2580 // --- Choosing an allocation function ---
2581 // C++ 5.3.4p8 - 14 & 18
2582 // 1) If looking in AFS_Global scope for allocation functions, only look in
2583 // the global scope. Else, if AFS_Class, only look in the scope of the
2584 // allocated class. If AFS_Both, look in both.
2585 // 2) If an array size is given, look for operator new[], else look for
2586 // operator new.
2587 // 3) The first argument is always size_t. Append the arguments from the
2588 // placement form.
2589
2590 SmallVector<Expr*, 8> AllocArgs;
2591 AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2592
2593 // We don't care about the actual value of these arguments.
2594 // FIXME: Should the Sema create the expression and embed it in the syntax
2595 // tree? Or should the consumer just recalculate the value?
2596 // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2597 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
2598 Context.getTargetInfo().getPointerWidth(0)),
2599 Context.getSizeType(),
2600 SourceLocation());
2601 AllocArgs.push_back(&Size);
2602
2603 QualType AlignValT = Context.VoidTy;
2604 if (PassAlignment) {
2605 DeclareGlobalNewDelete();
2606 AlignValT = Context.getTypeDeclType(getStdAlignValT());
2607 }
2608 CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2609 if (PassAlignment)
2610 AllocArgs.push_back(&Align);
2611
2612 AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2613
2614 // C++ [expr.new]p8:
2615 // If the allocated type is a non-array type, the allocation
2616 // function's name is operator new and the deallocation function's
2617 // name is operator delete. If the allocated type is an array
2618 // type, the allocation function's name is operator new[] and the
2619 // deallocation function's name is operator delete[].
2620 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
2621 IsArray ? OO_Array_New : OO_New);
2622
2623 QualType AllocElemType = Context.getBaseElementType(AllocType);
2624
2625 // Find the allocation function.
2626 {
2627 LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2628
2629 // C++1z [expr.new]p9:
2630 // If the new-expression begins with a unary :: operator, the allocation
2631 // function's name is looked up in the global scope. Otherwise, if the
2632 // allocated type is a class type T or array thereof, the allocation
2633 // function's name is looked up in the scope of T.
2634 if (AllocElemType->isRecordType() && NewScope != AFS_Global)
2635 LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2636
2637 // We can see ambiguity here if the allocation function is found in
2638 // multiple base classes.
2639 if (R.isAmbiguous())
2640 return true;
2641
2642 // If this lookup fails to find the name, or if the allocated type is not
2643 // a class type, the allocation function's name is looked up in the
2644 // global scope.
2645 if (R.empty()) {
2646 if (NewScope == AFS_Class)
2647 return true;
2648
2649 LookupQualifiedName(R, Context.getTranslationUnitDecl());
2650 }
2651
2652 if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
2653 if (PlaceArgs.empty()) {
2654 Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
2655 } else {
2656 Diag(StartLoc, diag::err_openclcxx_placement_new);
2657 }
2658 return true;
2659 }
2660
2661 assert(!R.empty() && "implicitly declared allocation functions not found")(static_cast<void> (0));
2662 assert(!R.isAmbiguous() && "global allocation functions are ambiguous")(static_cast<void> (0));
2663
2664 // We do our own custom access checks below.
2665 R.suppressDiagnostics();
2666
2667 if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2668 OperatorNew, /*Candidates=*/nullptr,
2669 /*AlignArg=*/nullptr, Diagnose))
2670 return true;
2671 }
2672
2673 // We don't need an operator delete if we're running under -fno-exceptions.
2674 if (!getLangOpts().Exceptions) {
2675 OperatorDelete = nullptr;
2676 return false;
2677 }
2678
2679 // Note, the name of OperatorNew might have been changed from array to
2680 // non-array by resolveAllocationOverload.
2681 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2682 OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2683 ? OO_Array_Delete
2684 : OO_Delete);
2685
2686 // C++ [expr.new]p19:
2687 //
2688 // If the new-expression begins with a unary :: operator, the
2689 // deallocation function's name is looked up in the global
2690 // scope. Otherwise, if the allocated type is a class type T or an
2691 // array thereof, the deallocation function's name is looked up in
2692 // the scope of T. If this lookup fails to find the name, or if
2693 // the allocated type is not a class type or array thereof, the
2694 // deallocation function's name is looked up in the global scope.
2695 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2696 if (AllocElemType->isRecordType() && DeleteScope != AFS_Global) {
2697 auto *RD =
2698 cast<CXXRecordDecl>(AllocElemType->castAs<RecordType>()->getDecl());
2699 LookupQualifiedName(FoundDelete, RD);
2700 }
2701 if (FoundDelete.isAmbiguous())
2702 return true; // FIXME: clean up expressions?
2703
2704 // Filter out any destroying operator deletes. We can't possibly call such a
2705 // function in this context, because we're handling the case where the object
2706 // was not successfully constructed.
2707 // FIXME: This is not covered by the language rules yet.
2708 {
2709 LookupResult::Filter Filter = FoundDelete.makeFilter();
2710 while (Filter.hasNext()) {
2711 auto *FD = dyn_cast<FunctionDecl>(Filter.next()->getUnderlyingDecl());
2712 if (FD && FD->isDestroyingOperatorDelete())
2713 Filter.erase();
2714 }
2715 Filter.done();
2716 }
2717
2718 bool FoundGlobalDelete = FoundDelete.empty();
2719 if (FoundDelete.empty()) {
2720 FoundDelete.clear(LookupOrdinaryName);
2721
2722 if (DeleteScope == AFS_Class)
2723 return true;
2724
2725 DeclareGlobalNewDelete();
2726 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2727 }
2728
2729 FoundDelete.suppressDiagnostics();
2730
2731 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2732
2733 // Whether we're looking for a placement operator delete is dictated
2734 // by whether we selected a placement operator new, not by whether
2735 // we had explicit placement arguments. This matters for things like
2736 // struct A { void *operator new(size_t, int = 0); ... };
2737 // A *a = new A()
2738 //
2739 // We don't have any definition for what a "placement allocation function"
2740 // is, but we assume it's any allocation function whose
2741 // parameter-declaration-clause is anything other than (size_t).
2742 //
2743 // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2744 // This affects whether an exception from the constructor of an overaligned
2745 // type uses the sized or non-sized form of aligned operator delete.
2746 bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2747 OperatorNew->isVariadic();
2748
2749 if (isPlacementNew) {
2750 // C++ [expr.new]p20:
2751 // A declaration of a placement deallocation function matches the
2752 // declaration of a placement allocation function if it has the
2753 // same number of parameters and, after parameter transformations
2754 // (8.3.5), all parameter types except the first are
2755 // identical. [...]
2756 //
2757 // To perform this comparison, we compute the function type that
2758 // the deallocation function should have, and use that type both
2759 // for template argument deduction and for comparison purposes.
2760 QualType ExpectedFunctionType;
2761 {
2762 auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2763
2764 SmallVector<QualType, 4> ArgTypes;
2765 ArgTypes.push_back(Context.VoidPtrTy);
2766 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2767 ArgTypes.push_back(Proto->getParamType(I));
2768
2769 FunctionProtoType::ExtProtoInfo EPI;
2770 // FIXME: This is not part of the standard's rule.
2771 EPI.Variadic = Proto->isVariadic();
2772
2773 ExpectedFunctionType
2774 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2775 }
2776
2777 for (LookupResult::iterator D = FoundDelete.begin(),
2778 DEnd = FoundDelete.end();
2779 D != DEnd; ++D) {
2780 FunctionDecl *Fn = nullptr;
2781 if (FunctionTemplateDecl *FnTmpl =
2782 dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2783 // Perform template argument deduction to try to match the
2784 // expected function type.
2785 TemplateDeductionInfo Info(StartLoc);
2786 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2787 Info))
2788 continue;
2789 } else
2790 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2791
2792 if (Context.hasSameType(adjustCCAndNoReturn(Fn->getType(),
2793 ExpectedFunctionType,
2794 /*AdjustExcpetionSpec*/true),
2795 ExpectedFunctionType))
2796 Matches.push_back(std::make_pair(D.getPair(), Fn));
2797 }
2798
2799 if (getLangOpts().CUDA)
2800 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2801 } else {
2802 // C++1y [expr.new]p22:
2803 // For a non-placement allocation function, the normal deallocation
2804 // function lookup is used
2805 //
2806 // Per [expr.delete]p10, this lookup prefers a member operator delete
2807 // without a size_t argument, but prefers a non-member operator delete
2808 // with a size_t where possible (which it always is in this case).
2809 llvm::SmallVector<UsualDeallocFnInfo, 4> BestDeallocFns;
2810 UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2811 *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2812 /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2813 &BestDeallocFns);
2814 if (Selected)
2815 Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2816 else {
2817 // If we failed to select an operator, all remaining functions are viable
2818 // but ambiguous.
2819 for (auto Fn : BestDeallocFns)
2820 Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2821 }
2822 }
2823
2824 // C++ [expr.new]p20:
2825 // [...] If the lookup finds a single matching deallocation
2826 // function, that function will be called; otherwise, no
2827 // deallocation function will be called.
2828 if (Matches.size() == 1) {
2829 OperatorDelete = Matches[0].second;
2830
2831 // C++1z [expr.new]p23:
2832 // If the lookup finds a usual deallocation function (3.7.4.2)
2833 // with a parameter of type std::size_t and that function, considered
2834 // as a placement deallocation function, would have been
2835 // selected as a match for the allocation function, the program
2836 // is ill-formed.
2837 if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2838 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2839 UsualDeallocFnInfo Info(*this,
2840 DeclAccessPair::make(OperatorDelete, AS_public));
2841 // Core issue, per mail to core reflector, 2016-10-09:
2842 // If this is a member operator delete, and there is a corresponding
2843 // non-sized member operator delete, this isn't /really/ a sized
2844 // deallocation function, it just happens to have a size_t parameter.
2845 bool IsSizedDelete = Info.HasSizeT;
2846 if (IsSizedDelete && !FoundGlobalDelete) {
2847 auto NonSizedDelete =
2848 resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2849 /*WantAlign*/Info.HasAlignValT);
2850 if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2851 NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2852 IsSizedDelete = false;
2853 }
2854
2855 if (IsSizedDelete) {
2856 SourceRange R = PlaceArgs.empty()
2857 ? SourceRange()
2858 : SourceRange(PlaceArgs.front()->getBeginLoc(),
2859 PlaceArgs.back()->getEndLoc());
2860 Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2861 if (!OperatorDelete->isImplicit())
2862 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2863 << DeleteName;
2864 }
2865 }
2866
2867 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2868 Matches[0].first);
2869 } else if (!Matches.empty()) {
2870 // We found multiple suitable operators. Per [expr.new]p20, that means we
2871 // call no 'operator delete' function, but we should at least warn the user.
2872 // FIXME: Suppress this warning if the construction cannot throw.
2873 Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2874 << DeleteName << AllocElemType;
2875
2876 for (auto &Match : Matches)
2877 Diag(Match.second->getLocation(),
2878 diag::note_member_declared_here) << DeleteName;
2879 }
2880
2881 return false;
2882}
2883
2884/// DeclareGlobalNewDelete - Declare the global forms of operator new and
2885/// delete. These are:
2886/// @code
2887/// // C++03:
2888/// void* operator new(std::size_t) throw(std::bad_alloc);
2889/// void* operator new[](std::size_t) throw(std::bad_alloc);
2890/// void operator delete(void *) throw();
2891/// void operator delete[](void *) throw();
2892/// // C++11:
2893/// void* operator new(std::size_t);
2894/// void* operator new[](std::size_t);
2895/// void operator delete(void *) noexcept;
2896/// void operator delete[](void *) noexcept;
2897/// // C++1y:
2898/// void* operator new(std::size_t);
2899/// void* operator new[](std::size_t);
2900/// void operator delete(void *) noexcept;
2901/// void operator delete[](void *) noexcept;
2902/// void operator delete(void *, std::size_t) noexcept;
2903/// void operator delete[](void *, std::size_t) noexcept;
2904/// @endcode
2905/// Note that the placement and nothrow forms of new are *not* implicitly
2906/// declared. Their use requires including \<new\>.
2907void Sema::DeclareGlobalNewDelete() {
2908 if (GlobalNewDeleteDeclared)
2909 return;
2910
2911 // The implicitly declared new and delete operators
2912 // are not supported in OpenCL.
2913 if (getLangOpts().OpenCLCPlusPlus)
2914 return;
2915
2916 // C++ [basic.std.dynamic]p2:
2917 // [...] The following allocation and deallocation functions (18.4) are
2918 // implicitly declared in global scope in each translation unit of a
2919 // program
2920 //
2921 // C++03:
2922 // void* operator new(std::size_t) throw(std::bad_alloc);
2923 // void* operator new[](std::size_t) throw(std::bad_alloc);
2924 // void operator delete(void*) throw();
2925 // void operator delete[](void*) throw();
2926 // C++11:
2927 // void* operator new(std::size_t);
2928 // void* operator new[](std::size_t);
2929 // void operator delete(void*) noexcept;
2930 // void operator delete[](void*) noexcept;
2931 // C++1y:
2932 // void* operator new(std::size_t);
2933 // void* operator new[](std::size_t);
2934 // void operator delete(void*) noexcept;
2935 // void operator delete[](void*) noexcept;
2936 // void operator delete(void*, std::size_t) noexcept;
2937 // void operator delete[](void*, std::size_t) noexcept;
2938 //
2939 // These implicit declarations introduce only the function names operator
2940 // new, operator new[], operator delete, operator delete[].
2941 //
2942 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2943 // "std" or "bad_alloc" as necessary to form the exception specification.
2944 // However, we do not make these implicit declarations visible to name
2945 // lookup.
2946 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2947 // The "std::bad_alloc" class has not yet been declared, so build it
2948 // implicitly.
2949 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2950 getOrCreateStdNamespace(),
2951 SourceLocation(), SourceLocation(),
2952 &PP.getIdentifierTable().get("bad_alloc"),
2953 nullptr);
2954 getStdBadAlloc()->setImplicit(true);
2955 }
2956 if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2957 // The "std::align_val_t" enum class has not yet been declared, so build it
2958 // implicitly.
2959 auto *AlignValT = EnumDecl::Create(
2960 Context, getOrCreateStdNamespace(), SourceLocation(), SourceLocation(),
2961 &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2962 AlignValT->setIntegerType(Context.getSizeType());
2963 AlignValT->setPromotionType(Context.getSizeType());
2964 AlignValT->setImplicit(true);
2965 StdAlignValT = AlignValT;
2966 }
2967
2968 GlobalNewDeleteDeclared = true;
2969
2970 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2971 QualType SizeT = Context.getSizeType();
2972
2973 auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2974 QualType Return, QualType Param) {
2975 llvm::SmallVector<QualType, 3> Params;
2976 Params.push_back(Param);
2977
2978 // Create up to four variants of the function (sized/aligned).
2979 bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2980 (Kind == OO_Delete || Kind == OO_Array_Delete);
2981 bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2982
2983 int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2984 int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2985 for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2986 if (Sized)
2987 Params.push_back(SizeT);
2988
2989 for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2990 if (Aligned)
2991 Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2992
2993 DeclareGlobalAllocationFunction(
2994 Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2995
2996 if (Aligned)
2997 Params.pop_back();
2998 }
2999 }
3000 };
3001
3002 DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
3003 DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
3004 DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
3005 DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
3006}
3007
3008/// DeclareGlobalAllocationFunction - Declares a single implicit global
3009/// allocation function if it doesn't already exist.
3010void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
3011 QualType Return,
3012 ArrayRef<QualType> Params) {
3013 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
3014
3015 // Check if this function is already declared.
3016 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
3017 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
3018 Alloc != AllocEnd; ++Alloc) {
3019 // Only look at non-template functions, as it is the predefined,
3020 // non-templated allocation function we are trying to declare here.
3021 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
3022 if (Func->getNumParams() == Params.size()) {
3023 llvm::SmallVector<QualType, 3> FuncParams;
3024 for (auto *P : Func->parameters())
3025 FuncParams.push_back(
3026 Context.getCanonicalType(P->getType().getUnqualifiedType()));
3027 if (llvm::makeArrayRef(FuncParams) == Params) {
3028 // Make the function visible to name lookup, even if we found it in
3029 // an unimported module. It either is an implicitly-declared global
3030 // allocation function, or is suppressing that function.
3031 Func->setVisibleDespiteOwningModule();
3032 return;
3033 }
3034 }
3035 }
3036 }
3037
3038 FunctionProtoType::ExtProtoInfo EPI(Context.getDefaultCallingConvention(
3039 /*IsVariadic=*/false, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
3040
3041 QualType BadAllocType;
3042 bool HasBadAllocExceptionSpec
3043 = (Name.getCXXOverloadedOperator() == OO_New ||
3044 Name.getCXXOverloadedOperator() == OO_Array_New);
3045 if (HasBadAllocExceptionSpec) {
3046 if (!getLangOpts().CPlusPlus11) {
3047 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
3048 assert(StdBadAlloc && "Must have std::bad_alloc declared")(static_cast<void> (0));
3049 EPI.ExceptionSpec.Type = EST_Dynamic;
3050 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
3051 }
3052 if (getLangOpts().NewInfallible) {
3053 EPI.ExceptionSpec.Type = EST_DynamicNone;
3054 }
3055 } else {
3056 EPI.ExceptionSpec =
3057 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
3058 }
3059
3060 auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
3061 QualType FnType = Context.getFunctionType(Return, Params, EPI);
3062 FunctionDecl *Alloc = FunctionDecl::Create(
3063 Context, GlobalCtx, SourceLocation(), SourceLocation(), Name, FnType,
3064 /*TInfo=*/nullptr, SC_None, getCurFPFeatures().isFPConstrained(), false,
3065 true);
3066 Alloc->setImplicit();
3067 // Global allocation functions should always be visible.
3068 Alloc->setVisibleDespiteOwningModule();
3069
3070 if (HasBadAllocExceptionSpec && getLangOpts().NewInfallible)
3071 Alloc->addAttr(
3072 ReturnsNonNullAttr::CreateImplicit(Context, Alloc->getLocation()));
3073
3074 Alloc->addAttr(VisibilityAttr::CreateImplicit(
3075 Context, LangOpts.GlobalAllocationFunctionVisibilityHidden
3076 ? VisibilityAttr::Hidden
3077 : VisibilityAttr::Default));
3078
3079 llvm::SmallVector<ParmVarDecl *, 3> ParamDecls;
3080 for (QualType T : Params) {
3081 ParamDecls.push_back(ParmVarDecl::Create(
3082 Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
3083 /*TInfo=*/nullptr, SC_None, nullptr));
3084 ParamDecls.back()->setImplicit();
3085 }
3086 Alloc->setParams(ParamDecls);
3087 if (ExtraAttr)
3088 Alloc->addAttr(ExtraAttr);
3089 AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction(Alloc);
3090 Context.getTranslationUnitDecl()->addDecl(Alloc);
3091 IdResolver.tryAddTopLevelDecl(Alloc, Name);
3092 };
3093
3094 if (!LangOpts.CUDA)
3095 CreateAllocationFunctionDecl(nullptr);
3096 else {
3097 // Host and device get their own declaration so each can be
3098 // defined or re-declared independently.
3099 CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
3100 CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
3101 }
3102}
3103
3104FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
3105 bool CanProvideSize,
3106 bool Overaligned,
3107 DeclarationName Name) {
3108 DeclareGlobalNewDelete();
3109
3110 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
3111 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
3112
3113 // FIXME: It's possible for this to result in ambiguity, through a
3114 // user-declared variadic operator delete or the enable_if attribute. We
3115 // should probably not consider those cases to be usual deallocation
3116 // functions. But for now we just make an arbitrary choice in that case.
3117 auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
3118 Overaligned);
3119 assert(Result.FD && "operator delete missing from global scope?")(static_cast<void> (0));
3120 return Result.FD;
3121}
3122
3123FunctionDecl *Sema::FindDeallocationFunctionForDestructor(SourceLocation Loc,
3124 CXXRecordDecl *RD) {
3125 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
3126
3127 FunctionDecl *OperatorDelete = nullptr;
3128 if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
3129 return nullptr;
3130 if (OperatorDelete)
3131 return OperatorDelete;
3132
3133 // If there's no class-specific operator delete, look up the global
3134 // non-array delete.
3135 return FindUsualDeallocationFunction(
3136 Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
3137 Name);
3138}
3139
3140bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
3141 DeclarationName Name,
3142 FunctionDecl *&Operator, bool Diagnose) {
3143 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
3144 // Try to find operator delete/operator delete[] in class scope.
3145 LookupQualifiedName(Found, RD);
3146
3147 if (Found.isAmbiguous())
3148 return true;
3149
3150 Found.suppressDiagnostics();
3151
3152 bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
3153
3154 // C++17 [expr.delete]p10:
3155 // If the deallocation functions have class scope, the one without a
3156 // parameter of type std::size_t is selected.
3157 llvm::SmallVector<UsualDeallocFnInfo, 4> Matches;
3158 resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
3159 /*WantAlign*/ Overaligned, &Matches);
3160
3161 // If we could find an overload, use it.
3162 if (Matches.size() == 1) {
3163 Operator = cast<CXXMethodDecl>(Matches[0].FD);
3164
3165 // FIXME: DiagnoseUseOfDecl?
3166 if (Operator->isDeleted()) {
3167 if (Diagnose) {
3168 Diag(StartLoc, diag::err_deleted_function_use);
3169 NoteDeletedFunction(Operator);
3170 }
3171 return true;
3172 }
3173
3174 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
3175 Matches[0].Found, Diagnose) == AR_inaccessible)
3176 return true;
3177
3178 return false;
3179 }
3180
3181 // We found multiple suitable operators; complain about the ambiguity.
3182 // FIXME: The standard doesn't say to do this; it appears that the intent
3183 // is that this should never happen.
3184 if (!Matches.empty()) {
3185 if (Diagnose) {
3186 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
3187 << Name << RD;
3188 for (auto &Match : Matches)
3189 Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
3190 }
3191 return true;
3192 }
3193
3194 // We did find operator delete/operator delete[] declarations, but
3195 // none of them were suitable.
3196 if (!Found.empty()) {
3197 if (Diagnose) {
3198 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
3199 << Name << RD;
3200
3201 for (NamedDecl *D : Found)
3202 Diag(D->getUnderlyingDecl()->getLocation(),
3203 diag::note_member_declared_here) << Name;
3204 }
3205 return true;
3206 }
3207
3208 Operator = nullptr;
3209 return false;
3210}
3211
3212namespace {
3213/// Checks whether delete-expression, and new-expression used for
3214/// initializing deletee have the same array form.
3215class MismatchingNewDeleteDetector {
3216public:
3217 enum MismatchResult {
3218 /// Indicates that there is no mismatch or a mismatch cannot be proven.
3219 NoMismatch,
3220 /// Indicates that variable is initialized with mismatching form of \a new.
3221 VarInitMismatches,
3222 /// Indicates that member is initialized with mismatching form of \a new.
3223 MemberInitMismatches,
3224 /// Indicates that 1 or more constructors' definitions could not been
3225 /// analyzed, and they will be checked again at the end of translation unit.
3226 AnalyzeLater
3227 };
3228
3229 /// \param EndOfTU True, if this is the final analysis at the end of
3230 /// translation unit. False, if this is the initial analysis at the point
3231 /// delete-expression was encountered.
3232 explicit MismatchingNewDeleteDetector(bool EndOfTU)
3233 : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
3234 HasUndefinedConstructors(false) {}
3235
3236 /// Checks whether pointee of a delete-expression is initialized with
3237 /// matching form of new-expression.
3238 ///
3239 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
3240 /// point where delete-expression is encountered, then a warning will be
3241 /// issued immediately. If return value is \c AnalyzeLater at the point where
3242 /// delete-expression is seen, then member will be analyzed at the end of
3243 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
3244 /// couldn't be analyzed. If at least one constructor initializes the member
3245 /// with matching type of new, the return value is \c NoMismatch.
3246 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
3247 /// Analyzes a class member.
3248 /// \param Field Class member to analyze.
3249 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
3250 /// for deleting the \p Field.
3251 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
3252 FieldDecl *Field;
3253 /// List of mismatching new-expressions used for initialization of the pointee
3254 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
3255 /// Indicates whether delete-expression was in array form.
3256 bool IsArrayForm;
3257
3258private:
3259 const bool EndOfTU;
3260 /// Indicates that there is at least one constructor without body.
3261 bool HasUndefinedConstructors;
3262 /// Returns \c CXXNewExpr from given initialization expression.
3263 /// \param E Expression used for initializing pointee in delete-expression.
3264 /// E can be a single-element \c InitListExpr consisting of new-expression.
3265 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
3266 /// Returns whether member is initialized with mismatching form of
3267 /// \c new either by the member initializer or in-class initialization.
3268 ///
3269 /// If bodies of all constructors are not visible at the end of translation
3270 /// unit or at least one constructor initializes member with the matching
3271 /// form of \c new, mismatch cannot be proven, and this function will return
3272 /// \c NoMismatch.
3273 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
3274 /// Returns whether variable is initialized with mismatching form of
3275 /// \c new.
3276 ///
3277 /// If variable is initialized with matching form of \c new or variable is not
3278 /// initialized with a \c new expression, this function will return true.
3279 /// If variable is initialized with mismatching form of \c new, returns false.
3280 /// \param D Variable to analyze.
3281 bool hasMatchingVarInit(const DeclRefExpr *D);
3282 /// Checks whether the constructor initializes pointee with mismatching
3283 /// form of \c new.
3284 ///
3285 /// Returns true, if member is initialized with matching form of \c new in
3286 /// member initializer list. Returns false, if member is initialized with the
3287 /// matching form of \c new in this constructor's initializer or given
3288 /// constructor isn't defined at the point where delete-expression is seen, or
3289 /// member isn't initialized by the constructor.
3290 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
3291 /// Checks whether member is initialized with matching form of
3292 /// \c new in member initializer list.
3293 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
3294 /// Checks whether member is initialized with mismatching form of \c new by
3295 /// in-class initializer.
3296 MismatchResult analyzeInClassInitializer();
3297};
3298}
3299
3300MismatchingNewDeleteDetector::MismatchResult
3301MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
3302 NewExprs.clear();
3303 assert(DE && "Expected delete-expression")(static_cast<void> (0));
3304 IsArrayForm = DE->isArrayForm();
3305 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
3306 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
3307 return analyzeMemberExpr(ME);
3308 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
3309 if (!hasMatchingVarInit(D))
3310 return VarInitMismatches;
3311 }
3312 return NoMismatch;
3313}
3314
3315const CXXNewExpr *
3316MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
3317 assert(E != nullptr && "Expected a valid initializer expression")(static_cast<void> (0));
3318 E = E->IgnoreParenImpCasts();
3319 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
3320 if (ILE->getNumInits() == 1)
3321 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
3322 }
3323
3324 return dyn_cast_or_null<const CXXNewExpr>(E);
3325}
3326
3327bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
3328 const CXXCtorInitializer *CI) {
3329 const CXXNewExpr *NE = nullptr;
3330 if (Field == CI->getMember() &&
3331 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
3332 if (NE->isArray() == IsArrayForm)
3333 return true;
3334 else
3335 NewExprs.push_back(NE);
3336 }
3337 return false;
3338}
3339
3340bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
3341 const CXXConstructorDecl *CD) {
3342 if (CD->isImplicit())
3343 return false;
3344 const FunctionDecl *Definition = CD;
3345 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
3346 HasUndefinedConstructors = true;
3347 return EndOfTU;
3348 }
3349 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
3350 if (hasMatchingNewInCtorInit(CI))
3351 return true;
3352 }
3353 return false;
3354}
3355
3356MismatchingNewDeleteDetector::MismatchResult
3357MismatchingNewDeleteDetector::analyzeInClassInitializer() {
3358 assert(Field != nullptr && "This should be called only for members")(static_cast<void> (0));
3359 const Expr *InitExpr = Field->getInClassInitializer();
3360 if (!InitExpr)
3361 return EndOfTU ? NoMismatch : AnalyzeLater;
3362 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
3363 if (NE->isArray() != IsArrayForm) {
3364 NewExprs.push_back(NE);
3365 return MemberInitMismatches;
3366 }
3367 }
3368 return NoMismatch;
3369}
3370
3371MismatchingNewDeleteDetector::MismatchResult
3372MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
3373 bool DeleteWasArrayForm) {
3374 assert(Field != nullptr && "Analysis requires a valid class member.")(static_cast<void> (0));
3375 this->Field = Field;
3376 IsArrayForm = DeleteWasArrayForm;
3377 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
3378 for (const auto *CD : RD->ctors()) {
3379 if (hasMatchingNewInCtor(CD))
3380 return NoMismatch;
3381 }
3382 if (HasUndefinedConstructors)
3383 return EndOfTU ? NoMismatch : AnalyzeLater;
3384 if (!NewExprs.empty())
3385 return MemberInitMismatches;
3386 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
3387 : NoMismatch;
3388}
3389
3390MismatchingNewDeleteDetector::MismatchResult
3391MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
3392 assert(ME != nullptr && "Expected a member expression")(static_cast<void> (0));
3393 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3394 return analyzeField(F, IsArrayForm);
3395 return NoMismatch;
3396}
3397
3398bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
3399 const CXXNewExpr *NE = nullptr;
3400 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
3401 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
3402 NE->isArray() != IsArrayForm) {
3403 NewExprs.push_back(NE);
3404 }
3405 }
3406 return NewExprs.empty();
3407}
3408
3409static void
3410DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
3411 const MismatchingNewDeleteDetector &Detector) {
3412 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
3413 FixItHint H;
3414 if (!Detector.IsArrayForm)
3415 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
3416 else {
3417 SourceLocation RSquare = Lexer::findLocationAfterToken(
3418 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
3419 SemaRef.getLangOpts(), true);
3420 if (RSquare.isValid())
3421 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
3422 }
3423 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
3424 << Detector.IsArrayForm << H;
3425
3426 for (const auto *NE : Detector.NewExprs)
3427 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
3428 << Detector.IsArrayForm;
3429}
3430
3431void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
3432 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
3433 return;
3434 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
3435 switch (Detector.analyzeDeleteExpr(DE)) {
3436 case MismatchingNewDeleteDetector::VarInitMismatches:
3437 case MismatchingNewDeleteDetector::MemberInitMismatches: {
3438 DiagnoseMismatchedNewDelete(*this, DE->getBeginLoc(), Detector);
3439 break;
3440 }
3441 case MismatchingNewDeleteDetector::AnalyzeLater: {
3442 DeleteExprs[Detector.Field].push_back(
3443 std::make_pair(DE->getBeginLoc(), DE->isArrayForm()));
3444 break;
3445 }
3446 case MismatchingNewDeleteDetector::NoMismatch:
3447 break;
3448 }
3449}
3450
3451void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3452 bool DeleteWasArrayForm) {
3453 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3454 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3455 case MismatchingNewDeleteDetector::VarInitMismatches:
3456 llvm_unreachable("This analysis should have been done for class members.")__builtin_unreachable();
3457 case MismatchingNewDeleteDetector::AnalyzeLater:
3458 llvm_unreachable("Analysis cannot be postponed any point beyond end of "__builtin_unreachable()
3459 "translation unit.")__builtin_unreachable();
3460 case MismatchingNewDeleteDetector::MemberInitMismatches:
3461 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3462 break;
3463 case MismatchingNewDeleteDetector::NoMismatch:
3464 break;
3465 }
3466}
3467
3468/// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3469/// @code ::delete ptr; @endcode
3470/// or
3471/// @code delete [] ptr; @endcode
3472ExprResult
3473Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3474 bool ArrayForm, Expr *ExE) {
3475 // C++ [expr.delete]p1:
3476 // The operand shall have a pointer type, or a class type having a single
3477 // non-explicit conversion function to a pointer type. The result has type
3478 // void.
3479 //
3480 // DR599 amends "pointer type" to "pointer to object type" in both cases.
3481
3482 ExprResult Ex = ExE;
3483 FunctionDecl *OperatorDelete = nullptr;
3484 bool ArrayFormAsWritten = ArrayForm;
3485 bool UsualArrayDeleteWantsSize = false;
3486
3487 if (!Ex.get()->isTypeDependent()) {
3488 // Perform lvalue-to-rvalue cast, if needed.
3489 Ex = DefaultLvalueConversion(Ex.get());
3490 if (Ex.isInvalid())
3491 return ExprError();
3492
3493 QualType Type = Ex.get()->getType();
3494
3495 class DeleteConverter : public ContextualImplicitConverter {
3496 public:
3497 DeleteConverter() : ContextualImplicitConverter(false, true) {}
3498
3499 bool match(QualType ConvType) override {
3500 // FIXME: If we have an operator T* and an operator void*, we must pick
3501 // the operator T*.
3502 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3503 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3504 return true;
3505 return false;
3506 }
3507
3508 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3509 QualType T) override {
3510 return S.Diag(Loc, diag::err_delete_operand) << T;
3511 }
3512
3513 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3514 QualType T) override {
3515 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3516 }
3517
3518 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3519 QualType T,
3520 QualType ConvTy) override {
3521 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3522 }
3523
3524 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3525 QualType ConvTy) override {
3526 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3527 << ConvTy;
3528 }
3529
3530 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3531 QualType T) override {
3532 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3533 }
3534
3535 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3536 QualType ConvTy) override {
3537 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3538 << ConvTy;
3539 }
3540
3541 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3542 QualType T,
3543 QualType ConvTy) override {
3544 llvm_unreachable("conversion functions are permitted")__builtin_unreachable();
3545 }
3546 } Converter;
3547
3548 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3549 if (Ex.isInvalid())
3550 return ExprError();
3551 Type = Ex.get()->getType();
3552 if (!Converter.match(Type))
3553 // FIXME: PerformContextualImplicitConversion should return ExprError
3554 // itself in this case.
3555 return ExprError();
3556
3557 QualType Pointee = Type->castAs<PointerType>()->getPointeeType();
3558 QualType PointeeElem = Context.getBaseElementType(Pointee);
3559
3560 if (Pointee.getAddressSpace() != LangAS::Default &&
3561 !getLangOpts().OpenCLCPlusPlus)
3562 return Diag(Ex.get()->getBeginLoc(),
3563 diag::err_address_space_qualified_delete)
3564 << Pointee.getUnqualifiedType()
3565 << Pointee.getQualifiers().getAddressSpaceAttributePrintValue();
3566
3567 CXXRecordDecl *PointeeRD = nullptr;
3568 if (Pointee->isVoidType() && !isSFINAEContext()) {
3569 // The C++ standard bans deleting a pointer to a non-object type, which
3570 // effectively bans deletion of "void*". However, most compilers support
3571 // this, so we treat it as a warning unless we're in a SFINAE context.
3572 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3573 << Type << Ex.get()->getSourceRange();
3574 } else if (Pointee->isFunctionType() || Pointee->isVoidType() ||
3575 Pointee->isSizelessType()) {
3576 return ExprError(Diag(StartLoc, diag::err_delete_operand)
3577 << Type << Ex.get()->getSourceRange());
3578 } else if (!Pointee->isDependentType()) {
3579 // FIXME: This can result in errors if the definition was imported from a
3580 // module but is hidden.
3581 if (!RequireCompleteType(StartLoc, Pointee,
3582 diag::warn_delete_incomplete, Ex.get())) {
3583 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3584 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3585 }
3586 }
3587
3588 if (Pointee->isArrayType() && !ArrayForm) {
3589 Diag(StartLoc, diag::warn_delete_array_type)
3590 << Type << Ex.get()->getSourceRange()
3591 << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3592 ArrayForm = true;
3593 }
3594
3595 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
3596 ArrayForm ? OO_Array_Delete : OO_Delete);
3597
3598 if (PointeeRD) {
3599 if (!UseGlobal &&
3600 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3601 OperatorDelete))
3602 return ExprError();
3603
3604 // If we're allocating an array of records, check whether the
3605 // usual operator delete[] has a size_t parameter.
3606 if (ArrayForm) {
3607 // If the user specifically asked to use the global allocator,
3608 // we'll need to do the lookup into the class.
3609 if (UseGlobal)
3610 UsualArrayDeleteWantsSize =
3611 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3612
3613 // Otherwise, the usual operator delete[] should be the
3614 // function we just found.
3615 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3616 UsualArrayDeleteWantsSize =
3617 UsualDeallocFnInfo(*this,
3618 DeclAccessPair::make(OperatorDelete, AS_public))
3619 .HasSizeT;
3620 }
3621
3622 if (!PointeeRD->hasIrrelevantDestructor())
3623 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3624 MarkFunctionReferenced(StartLoc,
3625 const_cast<CXXDestructorDecl*>(Dtor));
3626 if (DiagnoseUseOfDecl(Dtor, StartLoc))
3627 return ExprError();
3628 }
3629
3630 CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3631 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3632 /*WarnOnNonAbstractTypes=*/!ArrayForm,
3633 SourceLocation());
3634 }
3635
3636 if (!OperatorDelete) {
3637 if (getLangOpts().OpenCLCPlusPlus) {
3638 Diag(StartLoc, diag::err_openclcxx_not_supported) << "default delete";
3639 return ExprError();
3640 }
3641
3642 bool IsComplete = isCompleteType(StartLoc, Pointee);
3643 bool CanProvideSize =
3644 IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3645 Pointee.isDestructedType());
3646 bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3647
3648 // Look for a global declaration.
3649 OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3650 Overaligned, DeleteName);
3651 }
3652
3653 MarkFunctionReferenced(StartLoc, OperatorDelete);
3654
3655 // Check access and ambiguity of destructor if we're going to call it.
3656 // Note that this is required even for a virtual delete.
3657 bool IsVirtualDelete = false;
3658 if (PointeeRD) {
3659 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3660 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3661 PDiag(diag::err_access_dtor) << PointeeElem);
3662 IsVirtualDelete = Dtor->isVirtual();
3663 }
3664 }
3665
3666 DiagnoseUseOfDecl(OperatorDelete, StartLoc);
3667
3668 // Convert the operand to the type of the first parameter of operator
3669 // delete. This is only necessary if we selected a destroying operator
3670 // delete that we are going to call (non-virtually); converting to void*
3671 // is trivial and left to AST consumers to handle.
3672 QualType ParamType = OperatorDelete->getParamDecl(0)->getType();
3673 if (!IsVirtualDelete && !ParamType->getPointeeType()->isVoidType()) {
3674 Qualifiers Qs = Pointee.getQualifiers();
3675 if (Qs.hasCVRQualifiers()) {
3676 // Qualifiers are irrelevant to this conversion; we're only looking
3677 // for access and ambiguity.
3678 Qs.removeCVRQualifiers();
3679 QualType Unqual = Context.getPointerType(
3680 Context.getQualifiedType(Pointee.getUnqualifiedType(), Qs));
3681 Ex = ImpCastExprToType(Ex.get(), Unqual, CK_NoOp);
3682 }
3683 Ex = PerformImplicitConversion(Ex.get(), ParamType, AA_Passing);
3684 if (Ex.isInvalid())
3685 return ExprError();
3686 }
3687 }
3688
3689 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3690 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3691 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3692 AnalyzeDeleteExprMismatch(Result);
3693 return Result;
3694}
3695
3696static bool resolveBuiltinNewDeleteOverload(Sema &S, CallExpr *TheCall,
3697 bool IsDelete,
3698 FunctionDecl *&Operator) {
3699
3700 DeclarationName NewName = S.Context.DeclarationNames.getCXXOperatorName(
3701 IsDelete ? OO_Delete : OO_New);
5
Assuming 'IsDelete' is false
6
'?' condition is false
3702
3703 LookupResult R(S, NewName, TheCall->getBeginLoc(), Sema::LookupOrdinaryName);
3704 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
3705 assert(!R.empty() && "implicitly declared allocation functions not found")(static_cast<void> (0));
3706 assert(!R.isAmbiguous() && "global allocation functions are ambiguous")(static_cast<void> (0));
3707
3708 // We do our own custom access checks below.
3709 R.suppressDiagnostics();
3710
3711 SmallVector<Expr *, 8> Args(TheCall->arg_begin(), TheCall->arg_end());
3712 OverloadCandidateSet Candidates(R.getNameLoc(),
3713 OverloadCandidateSet::CSK_Normal);
3714 for (LookupResult::iterator FnOvl = R.begin(), FnOvlEnd = R.end();
7
Loop condition is false. Execution continues on line 3733
3715 FnOvl != FnOvlEnd; ++FnOvl) {
3716 // Even member operator new/delete are implicitly treated as
3717 // static, so don't use AddMemberCandidate.
3718 NamedDecl *D = (*FnOvl)->getUnderlyingDecl();
3719
3720 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
3721 S.AddTemplateOverloadCandidate(FnTemplate, FnOvl.getPair(),
3722 /*ExplicitTemplateArgs=*/nullptr, Args,
3723 Candidates,
3724 /*SuppressUserConversions=*/false);
3725 continue;
3726 }
3727
3728 FunctionDecl *Fn = cast<FunctionDecl>(D);
3729 S.AddOverloadCandidate(Fn, FnOvl.getPair(), Args, Candidates,
3730 /*SuppressUserConversions=*/false);
3731 }
3732
3733 SourceRange Range = TheCall->getSourceRange();
3734
3735 // Do the resolution.
3736 OverloadCandidateSet::iterator Best;
3737 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
8
Control jumps to 'case OR_Success:' at line 3738
3738 case OR_Success: {
3739 // Got one!
3740 FunctionDecl *FnDecl = Best->Function;
3741 assert(R.getNamingClass() == nullptr &&(static_cast<void> (0))
3742 "class members should not be considered")(static_cast<void> (0));
3743
3744 if (!FnDecl->isReplaceableGlobalAllocationFunction()) {
9
Assuming the condition is false
10
Taking false branch
3745 S.Diag(R.getNameLoc(), diag::err_builtin_operator_new_delete_not_usual)
3746 << (IsDelete ? 1 : 0) << Range;
3747 S.Diag(FnDecl->getLocation(), diag::note_non_usual_function_declared_here)
3748 << R.getLookupName() << FnDecl->getSourceRange();
3749 return true;
3750 }
3751
3752 Operator = FnDecl;
3753 return false;
11
Returning zero, which participates in a condition later
3754 }
3755
3756 case OR_No_Viable_Function:
3757 Candidates.NoteCandidates(
3758 PartialDiagnosticAt(R.getNameLoc(),
3759 S.PDiag(diag::err_ovl_no_viable_function_in_call)
3760 << R.getLookupName() << Range),
3761 S, OCD_AllCandidates, Args);
3762 return true;
3763
3764 case OR_Ambiguous:
3765 Candidates.NoteCandidates(
3766 PartialDiagnosticAt(R.getNameLoc(),
3767 S.PDiag(diag::err_ovl_ambiguous_call)
3768 << R.getLookupName() << Range),
3769 S, OCD_AmbiguousCandidates, Args);
3770 return true;
3771
3772 case OR_Deleted: {
3773 Candidates.NoteCandidates(
3774 PartialDiagnosticAt(R.getNameLoc(), S.PDiag(diag::err_ovl_deleted_call)
3775 << R.getLookupName() << Range),
3776 S, OCD_AllCandidates, Args);
3777 return true;
3778 }
3779 }
3780 llvm_unreachable("Unreachable, bad result from BestViableFunction")__builtin_unreachable();
3781}
3782
3783ExprResult
3784Sema::SemaBuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
3785 bool IsDelete) {
3786 CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
1
The object is a 'CallExpr'
3787 if (!getLangOpts().CPlusPlus) {
2
Assuming field 'CPlusPlus' is not equal to 0
3
Taking false branch
3788 Diag(TheCall->getExprLoc(), diag::err_builtin_requires_language)
3789 << (IsDelete ? "__builtin_operator_delete" : "__builtin_operator_new")
3790 << "C++";
3791 return ExprError();
3792 }
3793 // CodeGen assumes it can find the global new and delete to call,
3794 // so ensure that they are declared.
3795 DeclareGlobalNewDelete();
3796
3797 FunctionDecl *OperatorNewOrDelete = nullptr;
3798 if (resolveBuiltinNewDeleteOverload(*this, TheCall, IsDelete,
4
Calling 'resolveBuiltinNewDeleteOverload'
12
Returning from 'resolveBuiltinNewDeleteOverload'
13
Taking false branch
3799 OperatorNewOrDelete))
3800 return ExprError();
3801 assert(OperatorNewOrDelete && "should be found")(static_cast<void> (0));
3802
3803 DiagnoseUseOfDecl(OperatorNewOrDelete, TheCall->getExprLoc());
3804 MarkFunctionReferenced(TheCall->getExprLoc(), OperatorNewOrDelete);
3805
3806 TheCall->setType(OperatorNewOrDelete->getReturnType());
3807 for (unsigned i = 0; i != TheCall->getNumArgs(); ++i) {
14
Assuming the condition is false
15
Loop condition is false. Execution continues on line 3817
3808 QualType ParamTy = OperatorNewOrDelete->getParamDecl(i)->getType();
3809 InitializedEntity Entity =
3810 InitializedEntity::InitializeParameter(Context, ParamTy, false);
3811 ExprResult Arg = PerformCopyInitialization(
3812 Entity, TheCall->getArg(i)->getBeginLoc(), TheCall->getArg(i));
3813 if (Arg.isInvalid())
3814 return ExprError();
3815 TheCall->setArg(i, Arg.get());
3816 }
3817 auto Callee = dyn_cast<ImplicitCastExpr>(TheCall->getCallee());
16
Assuming the object is not a 'ImplicitCastExpr'
17
'Callee' initialized to a null pointer value
3818 assert(Callee && Callee->getCastKind() == CK_BuiltinFnToFnPtr &&(static_cast<void> (0))
3819 "Callee expected to be implicit cast to a builtin function pointer")(static_cast<void> (0));
3820 Callee->setType(OperatorNewOrDelete->getType());
18
Called C++ object pointer is null
3821
3822 return TheCallResult;
3823}
3824
3825void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3826 bool IsDelete, bool CallCanBeVirtual,
3827 bool WarnOnNonAbstractTypes,
3828 SourceLocation DtorLoc) {
3829 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual || isUnevaluatedContext())
3830 return;
3831
3832 // C++ [expr.delete]p3:
3833 // In the first alternative (delete object), if the static type of the
3834 // object to be deleted is different from its dynamic type, the static
3835 // type shall be a base class of the dynamic type of the object to be
3836 // deleted and the static type shall have a virtual destructor or the
3837 // behavior is undefined.
3838 //
3839 const CXXRecordDecl *PointeeRD = dtor->getParent();
3840 // Note: a final class cannot be derived from, no issue there
3841 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3842 return;
3843
3844 // If the superclass is in a system header, there's nothing that can be done.
3845 // The `delete` (where we emit the warning) can be in a system header,
3846 // what matters for this warning is where the deleted type is defined.
3847 if (getSourceManager().isInSystemHeader(PointeeRD->getLocation()))
3848 return;
3849
3850 QualType ClassType = dtor->getThisType()->getPointeeType();
3851 if (PointeeRD->isAbstract()) {
3852 // If the class is abstract, we warn by default, because we're
3853 // sure the code has undefined behavior.
3854 Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3855 << ClassType;
3856 } else if (WarnOnNonAbstractTypes) {
3857 // Otherwise, if this is not an array delete, it's a bit suspect,
3858 // but not necessarily wrong.
3859 Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3860 << ClassType;
3861 }
3862 if (!IsDelete) {
3863 std::string TypeStr;
3864 ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3865 Diag(DtorLoc, diag::note_delete_non_virtual)
3866 << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3867 }
3868}
3869
3870Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
3871 SourceLocation StmtLoc,
3872 ConditionKind CK) {
3873 ExprResult E =
3874 CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3875 if (E.isInvalid())
3876 return ConditionError();
3877 return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3878 CK == ConditionKind::ConstexprIf);
3879}
3880
3881/// Check the use of the given variable as a C++ condition in an if,
3882/// while, do-while, or switch statement.
3883ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
3884 SourceLocation StmtLoc,
3885 ConditionKind CK) {
3886 if (ConditionVar->isInvalidDecl())
3887 return ExprError();
3888
3889 QualType T = ConditionVar->getType();
3890
3891 // C++ [stmt.select]p2:
3892 // The declarator shall not specify a function or an array.
3893 if (T->isFunctionType())
3894 return ExprError(Diag(ConditionVar->getLocation(),
3895 diag::err_invalid_use_of_function_type)
3896 << ConditionVar->getSourceRange());
3897 else if (T->isArrayType())
3898 return ExprError(Diag(ConditionVar->getLocation(),
3899 diag::err_invalid_use_of_array_type)
3900 << ConditionVar->getSourceRange());
3901
3902 ExprResult Condition = BuildDeclRefExpr(
3903 ConditionVar, ConditionVar->getType().getNonReferenceType(), VK_LValue,
3904 ConditionVar->getLocation());
3905
3906 switch (CK) {
3907 case ConditionKind::Boolean:
3908 return CheckBooleanCondition(StmtLoc, Condition.get());
3909
3910 case ConditionKind::ConstexprIf:
3911 return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3912
3913 case ConditionKind::Switch:
3914 return CheckSwitchCondition(StmtLoc, Condition.get());
3915 }
3916
3917 llvm_unreachable("unexpected condition kind")__builtin_unreachable();
3918}
3919
3920/// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3921ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3922 // C++11 6.4p4:
3923 // The value of a condition that is an initialized declaration in a statement
3924 // other than a switch statement is the value of the declared variable
3925 // implicitly converted to type bool. If that conversion is ill-formed, the
3926 // program is ill-formed.
3927 // The value of a condition that is an expression is the value of the
3928 // expression, implicitly converted to bool.
3929 //
3930 // C++2b 8.5.2p2
3931 // If the if statement is of the form if constexpr, the value of the condition
3932 // is contextually converted to bool and the converted expression shall be
3933 // a constant expression.
3934 //
3935
3936 ExprResult E = PerformContextuallyConvertToBool(CondExpr);
3937 if (!IsConstexpr || E.isInvalid() || E.get()->isValueDependent())
3938 return E;
3939
3940 // FIXME: Return this value to the caller so they don't need to recompute it.
3941 llvm::APSInt Cond;
3942 E = VerifyIntegerConstantExpression(
3943 E.get(), &Cond,
3944 diag::err_constexpr_if_condition_expression_is_not_constant);
3945 return E;
3946}
3947
3948/// Helper function to determine whether this is the (deprecated) C++
3949/// conversion from a string literal to a pointer to non-const char or
3950/// non-const wchar_t (for narrow and wide string literals,
3951/// respectively).
3952bool
3953Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
3954 // Look inside the implicit cast, if it exists.
3955 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3956 From = Cast->getSubExpr();
3957
3958 // A string literal (2.13.4) that is not a wide string literal can
3959 // be converted to an rvalue of type "pointer to char"; a wide
3960 // string literal can be converted to an rvalue of type "pointer
3961 // to wchar_t" (C++ 4.2p2).
3962 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3963 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3964 if (const BuiltinType *ToPointeeType
3965 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3966 // This conversion is considered only when there is an
3967 // explicit appropriate pointer target type (C++ 4.2p2).
3968 if (!ToPtrType->getPointeeType().hasQualifiers()) {
3969 switch (StrLit->getKind()) {
3970 case StringLiteral::UTF8:
3971 case StringLiteral::UTF16:
3972 case StringLiteral::UTF32:
3973 // We don't allow UTF literals to be implicitly converted
3974 break;
3975 case StringLiteral::Ascii:
3976 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3977 ToPointeeType->getKind() == BuiltinType::Char_S);
3978 case StringLiteral::Wide:
3979 return Context.typesAreCompatible(Context.getWideCharType(),
3980 QualType(ToPointeeType, 0));
3981 }
3982 }
3983 }
3984
3985 return false;
3986}
3987
3988static ExprResult BuildCXXCastArgument(Sema &S,
3989 SourceLocation CastLoc,
3990 QualType Ty,
3991 CastKind Kind,
3992 CXXMethodDecl *Method,
3993 DeclAccessPair FoundDecl,
3994 bool HadMultipleCandidates,
3995 Expr *From) {
3996 switch (Kind) {
3997 default: llvm_unreachable("Unhandled cast kind!")__builtin_unreachable();
3998 case CK_ConstructorConversion: {
3999 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
4000 SmallVector<Expr*, 8> ConstructorArgs;
4001
4002 if (S.RequireNonAbstractType(CastLoc, Ty,
4003 diag::err_allocation_of_abstract_type))
4004 return ExprError();
4005
4006 if (S.CompleteConstructorCall(Constructor, Ty, From, CastLoc,
4007 ConstructorArgs))
4008 return ExprError();
4009
4010 S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
4011 InitializedEntity::InitializeTemporary(Ty));
4012 if (S.DiagnoseUseOfDecl(Method, CastLoc))
4013 return ExprError();
4014
4015 ExprResult Result = S.BuildCXXConstructExpr(
4016 CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
4017 ConstructorArgs, HadMultipleCandidates,
4018 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4019 CXXConstructExpr::CK_Complete, SourceRange());
4020 if (Result.isInvalid())
4021 return ExprError();
4022
4023 return S.MaybeBindToTemporary(Result.getAs<Expr>());
4024 }
4025
4026 case CK_UserDefinedConversion: {
4027 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!")(static_cast<void> (0));
4028
4029 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
4030 if (S.DiagnoseUseOfDecl(Method, CastLoc))
4031 return ExprError();
4032
4033 // Create an implicit call expr that calls it.
4034 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
4035 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
4036 HadMultipleCandidates);
4037 if (Result.isInvalid())
4038 return ExprError();
4039 // Record usage of conversion in an implicit cast.
4040 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
4041 CK_UserDefinedConversion, Result.get(),
4042 nullptr, Result.get()->getValueKind(),
4043 S.CurFPFeatureOverrides());
4044
4045 return S.MaybeBindToTemporary(Result.get());
4046 }
4047 }
4048}
4049
4050/// PerformImplicitConversion - Perform an implicit conversion of the
4051/// expression From to the type ToType using the pre-computed implicit
4052/// conversion sequence ICS. Returns the converted
4053/// expression. Action is the kind of conversion we're performing,
4054/// used in the error message.
4055ExprResult
4056Sema::PerformImplicitConversion(Expr *From, QualType ToType,
4057 const ImplicitConversionSequence &ICS,
4058 AssignmentAction Action,
4059 CheckedConversionKind CCK) {
4060 // C++ [over.match.oper]p7: [...] operands of class type are converted [...]
4061 if (CCK == CCK_ForBuiltinOverloadedOp && !From->getType()->isRecordType())
4062 return From;
4063
4064 switch (ICS.getKind()) {
4065 case ImplicitConversionSequence::StandardConversion: {
4066 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
4067 Action, CCK);
4068 if (Res.isInvalid())
4069 return ExprError();
4070 From = Res.get();
4071 break;
4072 }
4073
4074 case ImplicitConversionSequence::UserDefinedConversion: {
4075
4076 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
4077 CastKind CastKind;
4078 QualType BeforeToType;
4079 assert(FD && "no conversion function for user-defined conversion seq")(static_cast<void> (0));
4080 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
4081 CastKind = CK_UserDefinedConversion;
4082
4083 // If the user-defined conversion is specified by a conversion function,
4084 // the initial standard conversion sequence converts the source type to
4085 // the implicit object parameter of the conversion function.
4086 BeforeToType = Context.getTagDeclType(Conv->getParent());
4087 } else {
4088 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
4089 CastKind = CK_ConstructorConversion;
4090 // Do no conversion if dealing with ... for the first conversion.
4091 if (!ICS.UserDefined.EllipsisConversion) {
4092 // If the user-defined conversion is specified by a constructor, the
4093 // initial standard conversion sequence converts the source type to
4094 // the type required by the argument of the constructor
4095 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
4096 }
4097 }
4098 // Watch out for ellipsis conversion.
4099 if (!ICS.UserDefined.EllipsisConversion) {
4100 ExprResult Res =
4101 PerformImplicitConversion(From, BeforeToType,
4102 ICS.UserDefined.Before, AA_Converting,
4103 CCK);
4104 if (Res.isInvalid())
4105 return ExprError();
4106 From = Res.get();
4107 }
4108
4109 ExprResult CastArg = BuildCXXCastArgument(
4110 *this, From->getBeginLoc(), ToType.getNonReferenceType(), CastKind,
4111 cast<CXXMethodDecl>(FD), ICS.UserDefined.FoundConversionFunction,
4112 ICS.UserDefined.HadMultipleCandidates, From);
4113
4114 if (CastArg.isInvalid())
4115 return ExprError();
4116
4117 From = CastArg.get();
4118
4119 // C++ [over.match.oper]p7:
4120 // [...] the second standard conversion sequence of a user-defined
4121 // conversion sequence is not applied.
4122 if (CCK == CCK_ForBuiltinOverloadedOp)
4123 return From;
4124
4125 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
4126 AA_Converting, CCK);
4127 }
4128
4129 case ImplicitConversionSequence::AmbiguousConversion:
4130 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
4131 PDiag(diag::err_typecheck_ambiguous_condition)
4132 << From->getSourceRange());
4133 return ExprError();
4134
4135 case ImplicitConversionSequence::EllipsisConversion:
4136 llvm_unreachable("Cannot perform an ellipsis conversion")__builtin_unreachable();
4137
4138 case ImplicitConversionSequence::BadConversion:
4139 Sema::AssignConvertType ConvTy =
4140 CheckAssignmentConstraints(From->getExprLoc(), ToType, From->getType());
4141 bool Diagnosed = DiagnoseAssignmentResult(
4142 ConvTy == Compatible ? Incompatible : ConvTy, From->getExprLoc(),
4143 ToType, From->getType(), From, Action);
4144 assert(Diagnosed && "failed to diagnose bad conversion")(static_cast<void> (0)); (void)Diagnosed;
4145 return ExprError();
4146 }
4147
4148 // Everything went well.
4149 return From;
4150}
4151
4152/// PerformImplicitConversion - Perform an implicit conversion of the
4153/// expression From to the type ToType by following the standard
4154/// conversion sequence SCS. Returns the converted
4155/// expression. Flavor is the context in which we're performing this
4156/// conversion, for use in error messages.
4157ExprResult
4158Sema::PerformImplicitConversion(Expr *From, QualType ToType,
4159 const StandardConversionSequence& SCS,
4160 AssignmentAction Action,
4161 CheckedConversionKind CCK) {
4162 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
4163
4164 // Overall FIXME: we are recomputing too many types here and doing far too
4165 // much extra work. What this means is that we need to keep track of more
4166 // information that is computed when we try the implicit conversion initially,
4167 // so that we don't need to recompute anything here.
4168 QualType FromType = From->getType();
4169
4170 if (SCS.CopyConstructor) {
4171 // FIXME: When can ToType be a reference type?
4172 assert(!ToType->isReferenceType())(static_cast<void> (0));
4173 if (SCS.Second == ICK_Derived_To_Base) {
4174 SmallVector<Expr*, 8> ConstructorArgs;
4175 if (CompleteConstructorCall(
4176 cast<CXXConstructorDecl>(SCS.CopyConstructor), ToType, From,
4177 /*FIXME:ConstructLoc*/ SourceLocation(), ConstructorArgs))
4178 return ExprError();
4179 return BuildCXXConstructExpr(
4180 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
4181 SCS.FoundCopyConstructor, SCS.CopyConstructor,
4182 ConstructorArgs, /*HadMultipleCandidates*/ false,
4183 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4184 CXXConstructExpr::CK_Complete, SourceRange());
4185 }
4186 return BuildCXXConstructExpr(
4187 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
4188 SCS.FoundCopyConstructor, SCS.CopyConstructor,
4189 From, /*HadMultipleCandidates*/ false,
4190 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4191 CXXConstructExpr::CK_Complete, SourceRange());
4192 }
4193
4194 // Resolve overloaded function references.
4195 if (Context.hasSameType(FromType, Context.OverloadTy)) {
4196 DeclAccessPair Found;
4197 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
4198 true, Found);
4199 if (!Fn)
4200 return ExprError();
4201
4202 if (DiagnoseUseOfDecl(Fn, From->getBeginLoc()))
4203 return ExprError();
4204
4205 From = FixOverloadedFunctionReference(From, Found, Fn);
4206 FromType = From->getType();
4207 }
4208
4209 // If we're converting to an atomic type, first convert to the corresponding
4210 // non-atomic type.
4211 QualType ToAtomicType;
4212 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
4213 ToAtomicType = ToType;
4214 ToType = ToAtomic->getValueType();
4215 }
4216
4217 QualType InitialFromType = FromType;
4218 // Perform the first implicit conversion.
4219 switch (SCS.First) {
4220 case ICK_Identity:
4221 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
4222 FromType = FromAtomic->getValueType().getUnqualifiedType();
4223 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
4224 From, /*BasePath=*/nullptr, VK_PRValue,
4225 FPOptionsOverride());
4226 }
4227 break;
4228
4229 case ICK_Lvalue_To_Rvalue: {
4230 assert(From->getObjectKind() != OK_ObjCProperty)(static_cast<void> (0));
4231 ExprResult FromRes = DefaultLvalueConversion(From);
4232 if (FromRes.isInvalid())
4233 return ExprError();
4234
4235 From = FromRes.get();
4236 FromType = From->getType();
4237 break;
4238 }
4239
4240 case ICK_Array_To_Pointer:
4241 FromType = Context.getArrayDecayedType(FromType);
4242 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, VK_PRValue,
4243 /*BasePath=*/nullptr, CCK)
4244 .get();
4245 break;
4246
4247 case ICK_Function_To_Pointer:
4248 FromType = Context.getPointerType(FromType);
4249 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
4250 VK_PRValue, /*BasePath=*/nullptr, CCK)
4251 .get();
4252 break;
4253
4254 default:
4255 llvm_unreachable("Improper first standard conversion")__builtin_unreachable();
4256 }
4257
4258 // Perform the second implicit conversion
4259 switch (SCS.Second) {
4260 case ICK_Identity:
4261 // C++ [except.spec]p5:
4262 // [For] assignment to and initialization of pointers to functions,
4263 // pointers to member functions, and references to functions: the
4264 // target entity shall allow at least the exceptions allowed by the
4265 // source value in the assignment or initialization.
4266 switch (Action) {
4267 case AA_Assigning:
4268 case AA_Initializing:
4269 // Note, function argument passing and returning are initialization.
4270 case AA_Passing:
4271 case AA_Returning:
4272 case AA_Sending:
4273 case AA_Passing_CFAudited:
4274 if (CheckExceptionSpecCompatibility(From, ToType))
4275 return ExprError();
4276 break;
4277
4278 case AA_Casting:
4279 case AA_Converting:
4280 // Casts and implicit conversions are not initialization, so are not
4281 // checked for exception specification mismatches.
4282 break;
4283 }
4284 // Nothing else to do.
4285 break;
4286
4287 case ICK_Integral_Promotion:
4288 case ICK_Integral_Conversion:
4289 if (ToType->isBooleanType()) {
4290 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&(static_cast<void> (0))
4291 SCS.Second == ICK_Integral_Promotion &&(static_cast<void> (0))
4292 "only enums with fixed underlying type can promote to bool")(static_cast<void> (0));
4293 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, VK_PRValue,
4294 /*BasePath=*/nullptr, CCK)
4295 .get();
4296 } else {
4297 From = ImpCastExprToType(From, ToType, CK_IntegralCast, VK_PRValue,
4298 /*BasePath=*/nullptr, CCK)
4299 .get();
4300 }
4301 break;
4302
4303 case ICK_Floating_Promotion:
4304 case ICK_Floating_Conversion:
4305 From = ImpCastExprToType(From, ToType, CK_FloatingCast, VK_PRValue,
4306 /*BasePath=*/nullptr, CCK)
4307 .get();
4308 break;
4309
4310 case ICK_Complex_Promotion:
4311 case ICK_Complex_Conversion: {
4312 QualType FromEl = From->getType()->castAs<ComplexType>()->getElementType();
4313 QualType ToEl = ToType->castAs<ComplexType>()->getElementType();
4314 CastKind CK;
4315 if (FromEl->isRealFloatingType()) {
4316 if (ToEl->isRealFloatingType())
4317 CK = CK_FloatingComplexCast;
4318 else
4319 CK = CK_FloatingComplexToIntegralComplex;
4320 } else if (ToEl->isRealFloatingType()) {
4321 CK = CK_IntegralComplexToFloatingComplex;
4322 } else {
4323 CK = CK_IntegralComplexCast;
4324 }
4325 From = ImpCastExprToType(From, ToType, CK, VK_PRValue, /*BasePath=*/nullptr,
4326 CCK)
4327 .get();
4328 break;
4329 }
4330
4331 case ICK_Floating_Integral:
4332 if (ToType->isRealFloatingType())
4333 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, VK_PRValue,
4334 /*BasePath=*/nullptr, CCK)
4335 .get();
4336 else
4337 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, VK_PRValue,
4338 /*BasePath=*/nullptr, CCK)
4339 .get();
4340 break;
4341
4342 case ICK_Compatible_Conversion:
4343 From = ImpCastExprToType(From, ToType, CK_NoOp, From->getValueKind(),
4344 /*BasePath=*/nullptr, CCK).get();
4345 break;
4346
4347 case ICK_Writeback_Conversion:
4348 case ICK_Pointer_Conversion: {
4349 if (SCS.IncompatibleObjC && Action != AA_Casting) {
4350 // Diagnose incompatible Objective-C conversions
4351 if (Action == AA_Initializing || Action == AA_Assigning)
4352 Diag(From->getBeginLoc(),
4353 diag::ext_typecheck_convert_incompatible_pointer)
4354 << ToType << From->getType() << Action << From->getSourceRange()
4355 << 0;
4356 else
4357 Diag(From->getBeginLoc(),
4358 diag::ext_typecheck_convert_incompatible_pointer)
4359 << From->getType() << ToType << Action << From->getSourceRange()
4360 << 0;
4361
4362 if (From->getType()->isObjCObjectPointerType() &&
4363 ToType->isObjCObjectPointerType())
4364 EmitRelatedResultTypeNote(From);
4365 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
4366 !CheckObjCARCUnavailableWeakConversion(ToType,
4367 From->getType())) {
4368 if (Action == AA_Initializing)
4369 Diag(From->getBeginLoc(), diag::err_arc_weak_unavailable_assign);
4370 else
4371 Diag(From->getBeginLoc(), diag::err_arc_convesion_of_weak_unavailable)
4372 << (Action == AA_Casting) << From->getType() << ToType
4373 << From->getSourceRange();
4374 }
4375
4376 // Defer address space conversion to the third conversion.
4377 QualType FromPteeType = From->getType()->getPointeeType();
4378 QualType ToPteeType = ToType->getPointeeType();
4379 QualType NewToType = ToType;
4380 if (!FromPteeType.isNull() && !ToPteeType.isNull() &&
4381 FromPteeType.getAddressSpace() != ToPteeType.getAddressSpace()) {
4382 NewToType = Context.removeAddrSpaceQualType(ToPteeType);
4383 NewToType = Context.getAddrSpaceQualType(NewToType,
4384 FromPteeType.getAddressSpace());
4385 if (ToType->isObjCObjectPointerType())
4386 NewToType = Context.getObjCObjectPointerType(NewToType);
4387 else if (ToType->isBlockPointerType())
4388 NewToType = Context.getBlockPointerType(NewToType);
4389 else
4390 NewToType = Context.getPointerType(NewToType);
4391 }
4392
4393 CastKind Kind;
4394 CXXCastPath BasePath;
4395 if (CheckPointerConversion(From, NewToType, Kind, BasePath, CStyle))
4396 return ExprError();
4397
4398 // Make sure we extend blocks if necessary.
4399 // FIXME: doing this here is really ugly.
4400 if (Kind == CK_BlockPointerToObjCPointerCast) {
4401 ExprResult E = From;
4402 (void) PrepareCastToObjCObjectPointer(E);
4403 From = E.get();
4404 }
4405 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
4406 CheckObjCConversion(SourceRange(), NewToType, From, CCK);
4407 From = ImpCastExprToType(From, NewToType, Kind, VK_PRValue, &BasePath, CCK)
4408 .get();
4409 break;
4410 }
4411
4412 case ICK_Pointer_Member: {
4413 CastKind Kind;
4414 CXXCastPath BasePath;
4415 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
4416 return ExprError();
4417 if (CheckExceptionSpecCompatibility(From, ToType))
4418 return ExprError();
4419
4420 // We may not have been able to figure out what this member pointer resolved
4421 // to up until this exact point. Attempt to lock-in it's inheritance model.
4422 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
4423 (void)isCompleteType(From->getExprLoc(), From->getType());
4424 (void)isCompleteType(From->getExprLoc(), ToType);
4425 }
4426
4427 From =
4428 ImpCastExprToType(From, ToType, Kind, VK_PRValue, &BasePath, CCK).get();
4429 break;
4430 }
4431
4432 case ICK_Boolean_Conversion:
4433 // Perform half-to-boolean conversion via float.
4434 if (From->getType()->isHalfType()) {
4435 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
4436 FromType = Context.FloatTy;
4437 }
4438
4439 From = ImpCastExprToType(From, Context.BoolTy,
4440 ScalarTypeToBooleanCastKind(FromType), VK_PRValue,
4441 /*BasePath=*/nullptr, CCK)
4442 .get();
4443 break;
4444
4445 case ICK_Derived_To_Base: {
4446 CXXCastPath BasePath;
4447 if (CheckDerivedToBaseConversion(
4448 From->getType(), ToType.getNonReferenceType(), From->getBeginLoc(),
4449 From->getSourceRange(), &BasePath, CStyle))
4450 return ExprError();
4451
4452 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
4453 CK_DerivedToBase, From->getValueKind(),
4454 &BasePath, CCK).get();
4455 break;
4456 }
4457
4458 case ICK_Vector_Conversion:
4459 From = ImpCastExprToType(From, ToType, CK_BitCast, VK_PRValue,
4460 /*BasePath=*/nullptr, CCK)
4461 .get();
4462 break;
4463
4464 case ICK_SVE_Vector_Conversion:
4465 From = ImpCastExprToType(From, ToType, CK_BitCast, VK_PRValue,
4466 /*BasePath=*/nullptr, CCK)
4467 .get();
4468 break;
4469
4470 case ICK_Vector_Splat: {
4471 // Vector splat from any arithmetic type to a vector.
4472 Expr *Elem = prepareVectorSplat(ToType, From).get();
4473 From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_PRValue,
4474 /*BasePath=*/nullptr, CCK)
4475 .get();
4476 break;
4477 }
4478
4479 case ICK_Complex_Real:
4480 // Case 1. x -> _Complex y
4481 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
4482 QualType ElType = ToComplex->getElementType();
4483 bool isFloatingComplex = ElType->isRealFloatingType();
4484
4485 // x -> y
4486 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
4487 // do nothing
4488 } else if (From->getType()->isRealFloatingType()) {
4489 From = ImpCastExprToType(From, ElType,
4490 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
4491 } else {
4492 assert(From->getType()->isIntegerType())(static_cast<void> (0));
4493 From = ImpCastExprToType(From, ElType,
4494 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
4495 }
4496 // y -> _Complex y
4497 From = ImpCastExprToType(From, ToType,
4498 isFloatingComplex ? CK_FloatingRealToComplex
4499 : CK_IntegralRealToComplex).get();
4500
4501 // Case 2. _Complex x -> y
4502 } else {
4503 auto *FromComplex = From->getType()->castAs<ComplexType>();
4504 QualType ElType = FromComplex->getElementType();
4505 bool isFloatingComplex = ElType->isRealFloatingType();
4506
4507 // _Complex x -> x
4508 From = ImpCastExprToType(From, ElType,
4509 isFloatingComplex ? CK_FloatingComplexToReal
4510 : CK_IntegralComplexToReal,
4511 VK_PRValue, /*BasePath=*/nullptr, CCK)
4512 .get();
4513
4514 // x -> y
4515 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
4516 // do nothing
4517 } else if (ToType->isRealFloatingType()) {
4518 From = ImpCastExprToType(From, ToType,
4519 isFloatingComplex ? CK_FloatingCast
4520 : CK_IntegralToFloating,
4521 VK_PRValue, /*BasePath=*/nullptr, CCK)
4522 .get();
4523 } else {
4524 assert(ToType->isIntegerType())(static_cast<void> (0));
4525 From = ImpCastExprToType(From, ToType,
4526 isFloatingComplex ? CK_FloatingToIntegral
4527 : CK_IntegralCast,
4528 VK_PRValue, /*BasePath=*/nullptr, CCK)
4529 .get();
4530 }
4531 }
4532 break;
4533
4534 case ICK_Block_Pointer_Conversion: {
4535 LangAS AddrSpaceL =
4536 ToType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4537 LangAS AddrSpaceR =
4538 FromType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4539 assert(Qualifiers::isAddressSpaceSupersetOf(AddrSpaceL, AddrSpaceR) &&(static_cast<void> (0))
4540 "Invalid cast")(static_cast<void> (0));
4541 CastKind Kind =
4542 AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
4543 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), Kind,
4544 VK_PRValue, /*BasePath=*/nullptr, CCK)
4545 .get();
4546 break;
4547 }
4548
4549 case ICK_TransparentUnionConversion: {
4550 ExprResult FromRes = From;
4551 Sema::AssignConvertType ConvTy =
4552 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
4553 if (FromRes.isInvalid())
4554 return ExprError();
4555 From = FromRes.get();
4556 assert ((ConvTy == Sema::Compatible) &&(static_cast<void> (0))
4557 "Improper transparent union conversion")(static_cast<void> (0));
4558 (void)ConvTy;
4559 break;
4560 }
4561
4562 case ICK_Zero_Event_Conversion:
4563 case ICK_Zero_Queue_Conversion:
4564 From = ImpCastExprToType(From, ToType,
4565 CK_ZeroToOCLOpaqueType,
4566 From->getValueKind()).get();
4567 break;
4568
4569 case ICK_Lvalue_To_Rvalue:
4570 case ICK_Array_To_Pointer:
4571 case ICK_Function_To_Pointer:
4572 case ICK_Function_Conversion:
4573 case ICK_Qualification:
4574 case ICK_Num_Conversion_Kinds:
4575 case ICK_C_Only_Conversion:
4576 case ICK_Incompatible_Pointer_Conversion:
4577 llvm_unreachable("Improper second standard conversion")__builtin_unreachable();
4578 }
4579
4580 switch (SCS.Third) {
4581 case ICK_Identity:
4582 // Nothing to do.
4583 break;
4584
4585 case ICK_Function_Conversion:
4586 // If both sides are functions (or pointers/references to them), there could
4587 // be incompatible exception declarations.
4588 if (CheckExceptionSpecCompatibility(From, ToType))
4589 return ExprError();
4590
4591 From = ImpCastExprToType(From, ToType, CK_NoOp, VK_PRValue,
4592 /*BasePath=*/nullptr, CCK)
4593 .get();
4594 break;
4595
4596 case ICK_Qualification: {
4597 ExprValueKind VK = From->getValueKind();
4598 CastKind CK = CK_NoOp;
4599
4600 if (ToType->isReferenceType() &&
4601 ToType->getPointeeType().getAddressSpace() !=
4602 From->getType().getAddressSpace())
4603 CK = CK_AddressSpaceConversion;
4604
4605 if (ToType->isPointerType() &&
4606 ToType->getPointeeType().getAddressSpace() !=
4607 From->getType()->getPointeeType().getAddressSpace())
4608 CK = CK_AddressSpaceConversion;
4609
4610 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), CK, VK,
4611 /*BasePath=*/nullptr, CCK)
4612 .get();
4613
4614 if (SCS.DeprecatedStringLiteralToCharPtr &&
4615 !getLangOpts().WritableStrings) {
4616 Diag(From->getBeginLoc(),
4617 getLangOpts().CPlusPlus11
4618 ? diag::ext_deprecated_string_literal_conversion
4619 : diag::warn_deprecated_string_literal_conversion)
4620 << ToType.getNonReferenceType();
4621 }
4622
4623 break;
4624 }
4625
4626 default:
4627 llvm_unreachable("Improper third standard conversion")__builtin_unreachable();
4628 }
4629
4630 // If this conversion sequence involved a scalar -> atomic conversion, perform
4631 // that conversion now.
4632 if (!ToAtomicType.isNull()) {
4633 assert(Context.hasSameType((static_cast<void> (0))
4634 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()))(static_cast<void> (0));
4635 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
4636 VK_PRValue, nullptr, CCK)
4637 .get();
4638 }
4639
4640 // Materialize a temporary if we're implicitly converting to a reference
4641 // type. This is not required by the C++ rules but is necessary to maintain
4642 // AST invariants.
4643 if (ToType->isReferenceType() && From->isPRValue()) {
4644 ExprResult Res = TemporaryMaterializationConversion(From);
4645 if (Res.isInvalid())
4646 return ExprError();
4647 From = Res.get();
4648 }
4649
4650 // If this conversion sequence succeeded and involved implicitly converting a
4651 // _Nullable type to a _Nonnull one, complain.
4652 if (!isCast(CCK))
4653 diagnoseNullableToNonnullConversion(ToType, InitialFromType,
4654 From->getBeginLoc());
4655
4656 return From;
4657}
4658
4659/// Check the completeness of a type in a unary type trait.
4660///
4661/// If the particular type trait requires a complete type, tries to complete
4662/// it. If completing the type fails, a diagnostic is emitted and false
4663/// returned. If completing the type succeeds or no completion was required,
4664/// returns true.
4665static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
4666 SourceLocation Loc,
4667 QualType ArgTy) {
4668 // C++0x [meta.unary.prop]p3:
4669 // For all of the class templates X declared in this Clause, instantiating
4670 // that template with a template argument that is a class template
4671 // specialization may result in the implicit instantiation of the template
4672 // argument if and only if the semantics of X require that the argument
4673 // must be a complete type.
4674 // We apply this rule to all the type trait expressions used to implement
4675 // these class templates. We also try to follow any GCC documented behavior
4676 // in these expressions to ensure portability of standard libraries.
4677 switch (UTT) {
4678 default: llvm_unreachable("not a UTT")__builtin_unreachable();
4679 // is_complete_type somewhat obviously cannot require a complete type.
4680 case UTT_IsCompleteType:
4681 // Fall-through
4682
4683 // These traits are modeled on the type predicates in C++0x
4684 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4685 // requiring a complete type, as whether or not they return true cannot be
4686 // impacted by the completeness of the type.
4687 case UTT_IsVoid:
4688 case UTT_IsIntegral:
4689 case UTT_IsFloatingPoint:
4690 case UTT_IsArray:
4691 case UTT_IsPointer:
4692 case UTT_IsLvalueReference:
4693 case UTT_IsRvalueReference:
4694 case UTT_IsMemberFunctionPointer:
4695 case UTT_IsMemberObjectPointer:
4696 case UTT_IsEnum:
4697 case UTT_IsUnion:
4698 case UTT_IsClass:
4699 case UTT_IsFunction:
4700 case UTT_IsReference:
4701 case UTT_IsArithmetic:
4702 case UTT_IsFundamental:
4703 case UTT_IsObject:
4704 case UTT_IsScalar:
4705 case UTT_IsCompound:
4706 case UTT_IsMemberPointer:
4707 // Fall-through
4708
4709 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4710 // which requires some of its traits to have the complete type. However,
4711 // the completeness of the type cannot impact these traits' semantics, and
4712 // so they don't require it. This matches the comments on these traits in
4713 // Table 49.
4714 case UTT_IsConst:
4715 case UTT_IsVolatile:
4716 case UTT_IsSigned:
4717 case UTT_IsUnsigned:
4718
4719 // This type trait always returns false, checking the type is moot.
4720 case UTT_IsInterfaceClass:
4721 return true;
4722
4723 // C++14 [meta.unary.prop]:
4724 // If T is a non-union class type, T shall be a complete type.
4725 case UTT_IsEmpty:
4726 case UTT_IsPolymorphic:
4727 case UTT_IsAbstract:
4728 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4729 if (!RD->isUnion())
4730 return !S.RequireCompleteType(
4731 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4732 return true;
4733
4734 // C++14 [meta.unary.prop]:
4735 // If T is a class type, T shall be a complete type.
4736 case UTT_IsFinal:
4737 case UTT_IsSealed:
4738 if (ArgTy->getAsCXXRecordDecl())
4739 return !S.RequireCompleteType(
4740 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4741 return true;
4742
4743 // C++1z [meta.unary.prop]:
4744 // remove_all_extents_t<T> shall be a complete type or cv void.
4745 case UTT_IsAggregate:
4746 case UTT_IsTrivial:
4747 case UTT_IsTriviallyCopyable:
4748 case UTT_IsStandardLayout:
4749 case UTT_IsPOD:
4750 case UTT_IsLiteral:
4751 // Per the GCC type traits documentation, T shall be a complete type, cv void,
4752 // or an array of unknown bound. But GCC actually imposes the same constraints
4753 // as above.
4754 case UTT_HasNothrowAssign:
4755 case UTT_HasNothrowMoveAssign:
4756 case UTT_HasNothrowConstructor:
4757 case UTT_HasNothrowCopy:
4758 case UTT_HasTrivialAssign:
4759 case UTT_HasTrivialMoveAssign:
4760 case UTT_HasTrivialDefaultConstructor:
4761 case UTT_HasTrivialMoveConstructor:
4762 case UTT_HasTrivialCopy:
4763 case UTT_HasTrivialDestructor:
4764 case UTT_HasVirtualDestructor:
4765 ArgTy = QualType(ArgTy->getBaseElementTypeUnsafe(), 0);
4766 LLVM_FALLTHROUGH[[gnu::fallthrough]];
4767
4768 // C++1z [meta.unary.prop]:
4769 // T shall be a complete type, cv void, or an array of unknown bound.
4770 case UTT_IsDestructible:
4771 case UTT_IsNothrowDestructible:
4772 case UTT_IsTriviallyDestructible:
4773 case UTT_HasUniqueObjectRepresentations:
4774 if (ArgTy->isIncompleteArrayType() || ArgTy->isVoidType())
4775 return true;
4776
4777 return !S.RequireCompleteType(
4778 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4779 }
4780}
4781
4782static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
4783 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4784 bool (CXXRecordDecl::*HasTrivial)() const,
4785 bool (CXXRecordDecl::*HasNonTrivial)() const,
4786 bool (CXXMethodDecl::*IsDesiredOp)() const)
4787{
4788 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4789 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4790 return true;
4791
4792 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
4793 DeclarationNameInfo NameInfo(Name, KeyLoc);
4794 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4795 if (Self.LookupQualifiedName(Res, RD)) {
4796 bool FoundOperator = false;
4797 Res.suppressDiagnostics();
4798 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4799 Op != OpEnd; ++Op) {
4800 if (isa<FunctionTemplateDecl>(*Op))
4801 continue;
4802
4803 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4804 if((Operator->*IsDesiredOp)()) {
4805 FoundOperator = true;
4806 auto *CPT = Operator->getType()->castAs<FunctionProtoType>();
4807 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4808 if (!CPT || !CPT->isNothrow())
4809 return false;
4810 }
4811 }
4812 return FoundOperator;
4813 }
4814 return false;
4815}
4816
4817static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4818 SourceLocation KeyLoc, QualType T) {
4819 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type")(static_cast<void> (0));
4820
4821 ASTContext &C = Self.Context;
4822 switch(UTT) {
4823 default: llvm_unreachable("not a UTT")__builtin_unreachable();
4824 // Type trait expressions corresponding to the primary type category
4825 // predicates in C++0x [meta.unary.cat].
4826 case UTT_IsVoid:
4827 return T->isVoidType();
4828 case UTT_IsIntegral:
4829 return T->isIntegralType(C);
4830 case UTT_IsFloatingPoint:
4831 return T->isFloatingType();
4832 case UTT_IsArray:
4833 return T->isArrayType();
4834 case UTT_IsPointer:
4835 return T->isAnyPointerType();
4836 case UTT_IsLvalueReference:
4837 return T->isLValueReferenceType();
4838 case UTT_IsRvalueReference:
4839 return T->isRValueReferenceType();
4840 case UTT_IsMemberFunctionPointer:
4841 return T->isMemberFunctionPointerType();
4842 case UTT_IsMemberObjectPointer:
4843 return T->isMemberDataPointerType();
4844 case UTT_IsEnum:
4845 return T->isEnumeralType();
4846 case UTT_IsUnion:
4847 return T->isUnionType();
4848 case UTT_IsClass:
4849 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4850 case UTT_IsFunction:
4851 return T->isFunctionType();
4852
4853 // Type trait expressions which correspond to the convenient composition
4854 // predicates in C++0x [meta.unary.comp].
4855 case UTT_IsReference:
4856 return T->isReferenceType();
4857 case UTT_IsArithmetic:
4858 return T->isArithmeticType() && !T->isEnumeralType();
4859 case UTT_IsFundamental:
4860 return T->isFundamentalType();
4861 case UTT_IsObject:
4862 return T->isObjectType();
4863 case UTT_IsScalar:
4864 // Note: semantic analysis depends on Objective-C lifetime types to be
4865 // considered scalar types. However, such types do not actually behave
4866 // like scalar types at run time (since they may require retain/release
4867 // operations), so we report them as non-scalar.
4868 if (T->isObjCLifetimeType()) {
4869 switch (T.getObjCLifetime()) {
4870 case Qualifiers::OCL_None:
4871 case Qualifiers::OCL_ExplicitNone:
4872 return true;
4873
4874 case Qualifiers::OCL_Strong:
4875 case Qualifiers::OCL_Weak:
4876 case Qualifiers::OCL_Autoreleasing:
4877 return false;
4878 }
4879 }
4880
4881 return T->isScalarType();
4882 case UTT_IsCompound:
4883 return T->isCompoundType();
4884 case UTT_IsMemberPointer:
4885 return T->isMemberPointerType();
4886
4887 // Type trait expressions which correspond to the type property predicates
4888 // in C++0x [meta.unary.prop].
4889 case UTT_IsConst:
4890 return T.isConstQualified();
4891 case UTT_IsVolatile:
4892 return T.isVolatileQualified();
4893 case UTT_IsTrivial:
4894 return T.isTrivialType(C);
4895 case UTT_IsTriviallyCopyable:
4896 return T.isTriviallyCopyableType(C);
4897 case UTT_IsStandardLayout:
4898 return T->isStandardLayoutType();
4899 case UTT_IsPOD:
4900 return T.isPODType(C);
4901 case UTT_IsLiteral:
4902 return T->isLiteralType(C);
4903 case UTT_IsEmpty:
4904 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4905 return !RD->isUnion() && RD->isEmpty();
4906 return false;
4907 case UTT_IsPolymorphic:
4908 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4909 return !RD->isUnion() && RD->isPolymorphic();
4910 return false;
4911 case UTT_IsAbstract:
4912 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4913 return !RD->isUnion() && RD->isAbstract();
4914 return false;
4915 case UTT_IsAggregate:
4916 // Report vector extensions and complex types as aggregates because they
4917 // support aggregate initialization. GCC mirrors this behavior for vectors
4918 // but not _Complex.
4919 return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
4920 T->isAnyComplexType();
4921 // __is_interface_class only returns true when CL is invoked in /CLR mode and
4922 // even then only when it is used with the 'interface struct ...' syntax
4923 // Clang doesn't support /CLR which makes this type trait moot.
4924 case UTT_IsInterfaceClass:
4925 return false;
4926 case UTT_IsFinal:
4927 case UTT_IsSealed:
4928 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4929 return RD->hasAttr<FinalAttr>();
4930 return false;
4931 case UTT_IsSigned:
4932 // Enum types should always return false.
4933 // Floating points should always return true.
4934 return T->isFloatingType() ||
4935 (T->isSignedIntegerType() && !T->isEnumeralType());
4936 case UTT_IsUnsigned:
4937 // Enum types should always return false.
4938 return T->isUnsignedIntegerType() && !T->isEnumeralType();
4939
4940 // Type trait expressions which query classes regarding their construction,
4941 // destruction, and copying. Rather than being based directly on the
4942 // related type predicates in the standard, they are specified by both
4943 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4944 // specifications.
4945 //
4946 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4947 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4948 //
4949 // Note that these builtins do not behave as documented in g++: if a class
4950 // has both a trivial and a non-trivial special member of a particular kind,
4951 // they return false! For now, we emulate this behavior.
4952 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4953 // does not correctly compute triviality in the presence of multiple special
4954 // members of the same kind. Revisit this once the g++ bug is fixed.
4955 case UTT_HasTrivialDefaultConstructor:
4956 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4957 // If __is_pod (type) is true then the trait is true, else if type is
4958 // a cv class or union type (or array thereof) with a trivial default
4959 // constructor ([class.ctor]) then the trait is true, else it is false.
4960 if (T.isPODType(C))
4961 return true;
4962 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4963 return RD->hasTrivialDefaultConstructor() &&
4964 !RD->hasNonTrivialDefaultConstructor();
4965 return false;
4966 case UTT_HasTrivialMoveConstructor:
4967 // This trait is implemented by MSVC 2012 and needed to parse the
4968 // standard library headers. Specifically this is used as the logic
4969 // behind std::is_trivially_move_constructible (20.9.4.3).
4970 if (T.isPODType(C))
4971 return true;
4972 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4973 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4974 return false;
4975 case UTT_HasTrivialCopy:
4976 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4977 // If __is_pod (type) is true or type is a reference type then
4978 // the trait is true, else if type is a cv class or union type
4979 // with a trivial copy constructor ([class.copy]) then the trait
4980 // is true, else it is false.
4981 if (T.isPODType(C) || T->isReferenceType())
4982 return true;
4983 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4984 return RD->hasTrivialCopyConstructor() &&
4985 !RD->hasNonTrivialCopyConstructor();
4986 return false;
4987 case UTT_HasTrivialMoveAssign:
4988 // This trait is implemented by MSVC 2012 and needed to parse the
4989 // standard library headers. Specifically it is used as the logic
4990 // behind std::is_trivially_move_assignable (20.9.4.3)
4991 if (T.isPODType(C))
4992 return true;
4993 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4994 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4995 return false;
4996 case UTT_HasTrivialAssign:
4997 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4998 // If type is const qualified or is a reference type then the
4999 // trait is false. Otherwise if __is_pod (type) is true then the
5000 // trait is true, else if type is a cv class or union type with
5001 // a trivial copy assignment ([class.copy]) then the trait is
5002 // true, else it is false.
5003 // Note: the const and reference restrictions are interesting,
5004 // given that const and reference members don't prevent a class
5005 // from having a trivial copy assignment operator (but do cause
5006 // errors if the copy assignment operator is actually used, q.v.
5007 // [class.copy]p12).
5008
5009 if (T.isConstQualified())
5010 return false;
5011 if (T.isPODType(C))
5012 return true;
5013 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5014 return RD->hasTrivialCopyAssignment() &&
5015 !RD->hasNonTrivialCopyAssignment();
5016 return false;
5017 case UTT_IsDestructible:
5018 case UTT_IsTriviallyDestructible:
5019 case UTT_IsNothrowDestructible:
5020 // C++14 [meta.unary.prop]:
5021 // For reference types, is_destructible<T>::value is true.
5022 if (T->isReferenceType())
5023 return true;
5024
5025 // Objective-C++ ARC: autorelease types don't require destruction.
5026 if (T->isObjCLifetimeType() &&
5027 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
5028 return true;
5029
5030 // C++14 [meta.unary.prop]:
5031 // For incomplete types and function types, is_destructible<T>::value is
5032 // false.
5033 if (T->isIncompleteType() || T->isFunctionType())
5034 return false;
5035
5036 // A type that requires destruction (via a non-trivial destructor or ARC
5037 // lifetime semantics) is not trivially-destructible.
5038 if (UTT == UTT_IsTriviallyDestructible && T.isDestructedType())
5039 return false;
5040
5041 // C++14 [meta.unary.prop]:
5042 // For object types and given U equal to remove_all_extents_t<T>, if the
5043 // expression std::declval<U&>().~U() is well-formed when treated as an
5044 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
5045 if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
5046 CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
5047 if (!Destructor)
5048 return false;
5049 // C++14 [dcl.fct.def.delete]p2:
5050 // A program that refers to a deleted function implicitly or
5051 // explicitly, other than to declare it, is ill-formed.
5052 if (Destructor->isDeleted())
5053 return false;
5054 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
5055 return false;
5056 if (UTT == UTT_IsNothrowDestructible) {
5057 auto *CPT = Destructor->getType()->castAs<FunctionProtoType>();
5058 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5059 if (!CPT || !CPT->isNothrow())
5060 return false;
5061 }
5062 }
5063 return true;
5064
5065 case UTT_HasTrivialDestructor:
5066 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5067 // If __is_pod (type) is true or type is a reference type
5068 // then the trait is true, else if type is a cv class or union
5069 // type (or array thereof) with a trivial destructor
5070 // ([class.dtor]) then the trait is true, else it is
5071 // false.
5072 if (T.isPODType(C) || T->isReferenceType())
5073 return true;
5074
5075 // Objective-C++ ARC: autorelease types don't require destruction.
5076 if (T->isObjCLifetimeType() &&
5077 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
5078 return true;
5079
5080 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
5081 return RD->hasTrivialDestructor();
5082 return false;
5083 // TODO: Propagate nothrowness for implicitly declared special members.
5084 case UTT_HasNothrowAssign:
5085 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5086 // If type is const qualified or is a reference type then the
5087 // trait is false. Otherwise if __has_trivial_assign (type)
5088 // is true then the trait is true, else if type is a cv class
5089 // or union type with copy assignment operators that are known
5090 // not to throw an exception then the trait is true, else it is
5091 // false.
5092 if (C.getBaseElementType(T).isConstQualified())
5093 return false;
5094 if (T->isReferenceType())
5095 return false;
5096 if (T.isPODType(C) || T->isObjCLifetimeType())
5097 return true;
5098
5099 if (const RecordType *RT = T->getAs<RecordType>())
5100 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
5101 &CXXRecordDecl::hasTrivialCopyAssignment,
5102 &CXXRecordDecl::hasNonTrivialCopyAssignment,
5103 &CXXMethodDecl::isCopyAssignmentOperator);
5104 return false;
5105 case UTT_HasNothrowMoveAssign:
5106 // This trait is implemented by MSVC 2012 and needed to parse the
5107 // standard library headers. Specifically this is used as the logic
5108 // behind std::is_nothrow_move_assignable (20.9.4.3).
5109 if (T.isPODType(C))
5110 return true;
5111
5112 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
5113 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
5114 &CXXRecordDecl::hasTrivialMoveAssignment,
5115 &CXXRecordDecl::hasNonTrivialMoveAssignment,
5116 &CXXMethodDecl::isMoveAssignmentOperator);
5117 return false;
5118 case UTT_HasNothrowCopy:
5119 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5120 // If __has_trivial_copy (type) is true then the trait is true, else
5121 // if type is a cv class or union type with copy constructors that are
5122 // known not to throw an exception then the trait is true, else it is
5123 // false.
5124 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
5125 return true;
5126 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
5127 if (RD->hasTrivialCopyConstructor() &&
5128 !RD->hasNonTrivialCopyConstructor())
5129 return true;
5130
5131 bool FoundConstructor = false;
5132 unsigned FoundTQs;
5133 for (const auto *ND : Self.LookupConstructors(RD)) {
5134 // A template constructor is never a copy constructor.
5135 // FIXME: However, it may actually be selected at the actual overload
5136 // resolution point.
5137 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
5138 continue;
5139 // UsingDecl itself is not a constructor
5140 if (isa<UsingDecl>(ND))
5141 continue;
5142 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
5143 if (Constructor->isCopyConstructor(FoundTQs)) {
5144 FoundConstructor = true;
5145 auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5146 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5147 if (!CPT)
5148 return false;
5149 // TODO: check whether evaluating default arguments can throw.
5150 // For now, we'll be conservative and assume that they can throw.
5151 if (!CPT->isNothrow() || CPT->getNumParams() > 1)
5152 return false;
5153 }
5154 }
5155
5156 return FoundConstructor;
5157 }
5158 return false;
5159 case UTT_HasNothrowConstructor:
5160 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5161 // If __has_trivial_constructor (type) is true then the trait is
5162 // true, else if type is a cv class or union type (or array
5163 // thereof) with a default constructor that is known not to
5164 // throw an exception then the trait is true, else it is false.
5165 if (T.isPODType(C) || T->isObjCLifetimeType())
5166 return true;
5167 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
5168 if (RD->hasTrivialDefaultConstructor() &&
5169 !RD->hasNonTrivialDefaultConstructor())
5170 return true;
5171
5172 bool FoundConstructor = false;
5173 for (const auto *ND : Self.LookupConstructors(RD)) {
5174 // FIXME: In C++0x, a constructor template can be a default constructor.
5175 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
5176 continue;
5177 // UsingDecl itself is not a constructor
5178 if (isa<UsingDecl>(ND))
5179 continue;
5180 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
5181 if (Constructor->isDefaultConstructor()) {
5182 FoundConstructor = true;
5183 auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5184 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5185 if (!CPT)
5186 return false;
5187 // FIXME: check whether evaluating default arguments can throw.
5188 // For now, we'll be conservative and assume that they can throw.
5189 if (!CPT->isNothrow() || CPT->getNumParams() > 0)
5190 return false;
5191 }
5192 }
5193 return FoundConstructor;
5194 }
5195 return false;
5196 case UTT_HasVirtualDestructor:
5197 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5198 // If type is a class type with a virtual destructor ([class.dtor])
5199 // then the trait is true, else it is false.
5200 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5201 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
5202 return Destructor->isVirtual();
5203 return false;
5204
5205 // These type trait expressions are modeled on the specifications for the
5206 // Embarcadero C++0x type trait functions:
5207 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
5208 case UTT_IsCompleteType:
5209 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
5210 // Returns True if and only if T is a complete type at the point of the
5211 // function call.
5212 return !T->isIncompleteType();
5213 case UTT_HasUniqueObjectRepresentations:
5214 return C.hasUniqueObjectRepresentations(T);
5215 }
5216}
5217
5218static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
5219 QualType RhsT, SourceLocation KeyLoc);
5220
5221static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
5222 ArrayRef<TypeSourceInfo *> Args,
5223 SourceLocation RParenLoc) {
5224 if (Kind <= UTT_Last)
5225 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
5226
5227 // Evaluate BTT_ReferenceBindsToTemporary alongside the IsConstructible
5228 // traits to avoid duplication.
5229 if (Kind <= BTT_Last && Kind != BTT_ReferenceBindsToTemporary)
5230 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
5231 Args[1]->getType(), RParenLoc);
5232
5233 switch (Kind) {
5234 case clang::BTT_ReferenceBindsToTemporary:
5235 case clang::TT_IsConstructible:
5236 case clang::TT_IsNothrowConstructible:
5237 case clang::TT_IsTriviallyConstructible: {
5238 // C++11 [meta.unary.prop]:
5239 // is_trivially_constructible is defined as:
5240 //
5241 // is_constructible<T, Args...>::value is true and the variable
5242 // definition for is_constructible, as defined below, is known to call
5243 // no operation that is not trivial.
5244 //
5245 // The predicate condition for a template specialization
5246 // is_constructible<T, Args...> shall be satisfied if and only if the
5247 // following variable definition would be well-formed for some invented
5248 // variable t:
5249 //
5250 // T t(create<Args>()...);
5251 assert(!Args.empty())(static_cast<void> (0));
5252
5253 // Precondition: T and all types in the parameter pack Args shall be
5254 // complete types, (possibly cv-qualified) void, or arrays of
5255 // unknown bound.
5256 for (const auto *TSI : Args) {
5257 QualType ArgTy = TSI->getType();
5258 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
5259 continue;
5260
5261 if (S.RequireCompleteType(KWLoc, ArgTy,
5262 diag::err_incomplete_type_used_in_type_trait_expr))
5263 return false;
5264 }
5265
5266 // Make sure the first argument is not incomplete nor a function type.
5267 QualType T = Args[0]->getType();
5268 if (T->isIncompleteType() || T->isFunctionType())
5269 return false;
5270
5271 // Make sure the first argument is not an abstract type.
5272 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
5273 if (RD && RD->isAbstract())
5274 return false;
5275
5276 llvm::BumpPtrAllocator OpaqueExprAllocator;
5277 SmallVector<Expr *, 2> ArgExprs;
5278 ArgExprs.reserve(Args.size() - 1);
5279 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
5280 QualType ArgTy = Args[I]->getType();
5281 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
5282 ArgTy = S.Context.getRValueReferenceType(ArgTy);
5283 ArgExprs.push_back(
5284 new (OpaqueExprAllocator.Allocate<OpaqueValueExpr>())
5285 OpaqueValueExpr(Args[I]->getTypeLoc().getBeginLoc(),
5286 ArgTy.getNonLValueExprType(S.Context),
5287 Expr::getValueKindForType(ArgTy)));
5288 }
5289
5290 // Perform the initialization in an unevaluated context within a SFINAE
5291 // trap at translation unit scope.
5292 EnterExpressionEvaluationContext Unevaluated(
5293 S, Sema::ExpressionEvaluationContext::Unevaluated);
5294 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
5295 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
5296 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
5297 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
5298 RParenLoc));
5299 InitializationSequence Init(S, To, InitKind, ArgExprs);
5300 if (Init.Failed())
5301 return false;
5302
5303 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
5304 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5305 return false;
5306
5307 if (Kind == clang::TT_IsConstructible)
5308 return true;
5309
5310 if (Kind == clang::BTT_ReferenceBindsToTemporary) {
5311 if (!T->isReferenceType())
5312 return false;
5313
5314 return !Init.isDirectReferenceBinding();
5315 }
5316
5317 if (Kind == clang::TT_IsNothrowConstructible)
5318 return S.canThrow(Result.get()) == CT_Cannot;
5319
5320 if (Kind == clang::TT_IsTriviallyConstructible) {
5321 // Under Objective-C ARC and Weak, if the destination has non-trivial
5322 // Objective-C lifetime, this is a non-trivial construction.
5323 if (T.getNonReferenceType().hasNonTrivialObjCLifetime())
5324 return false;
5325
5326 // The initialization succeeded; now make sure there are no non-trivial
5327 // calls.
5328 return !Result.get()->hasNonTrivialCall(S.Context);
5329 }
5330
5331 llvm_unreachable("unhandled type trait")__builtin_unreachable();
5332 return false;
5333 }
5334 default: llvm_unreachable("not a TT")__builtin_unreachable();
5335 }
5336
5337 return false;
5338}
5339
5340ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
5341 ArrayRef<TypeSourceInfo *> Args,
5342 SourceLocation RParenLoc) {
5343 QualType ResultType = Context.getLogicalOperationType();
5344
5345 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
5346 *this, Kind, KWLoc, Args[0]->getType()))
5347 return ExprError();
5348
5349 bool Dependent = false;
5350 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5351 if (Args[I]->getType()->isDependentType()) {
5352 Dependent = true;
5353 break;
5354 }
5355 }
5356
5357 bool Result = false;
5358 if (!Dependent)
5359 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
5360
5361 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
5362 RParenLoc, Result);
5363}
5364
5365ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
5366 ArrayRef<ParsedType> Args,
5367 SourceLocation RParenLoc) {
5368 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
5369 ConvertedArgs.reserve(Args.size());
5370
5371 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5372 TypeSourceInfo *TInfo;
5373 QualType T = GetTypeFromParser(Args[I], &TInfo);
5374 if (!TInfo)
5375 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
5376
5377 ConvertedArgs.push_back(TInfo);
5378 }
5379
5380 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
5381}
5382
5383static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
5384 QualType RhsT, SourceLocation KeyLoc) {
5385 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&(static_cast<void> (0))
5386 "Cannot evaluate traits of dependent types")(static_cast<void> (0));
5387
5388 switch(BTT) {
5389 case BTT_IsBaseOf: {
5390 // C++0x [meta.rel]p2
5391 // Base is a base class of Derived without regard to cv-qualifiers or
5392 // Base and Derived are not unions and name the same class type without
5393 // regard to cv-qualifiers.
5394
5395 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
5396 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
5397 if (!rhsRecord || !lhsRecord) {
5398 const ObjCObjectType *LHSObjTy = LhsT->getAs<ObjCObjectType>();
5399 const ObjCObjectType *RHSObjTy = RhsT->getAs<ObjCObjectType>();
5400 if (!LHSObjTy || !RHSObjTy)
5401 return false;
5402
5403 ObjCInterfaceDecl *BaseInterface = LHSObjTy->getInterface();
5404 ObjCInterfaceDecl *DerivedInterface = RHSObjTy->getInterface();
5405 if (!BaseInterface || !DerivedInterface)
5406 return false;
5407
5408 if (Self.RequireCompleteType(
5409 KeyLoc, RhsT, diag::err_incomplete_type_used_in_type_trait_expr))
5410 return false;
5411
5412 return BaseInterface->isSuperClassOf(DerivedInterface);
5413 }
5414
5415 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)(static_cast<void> (0))
5416 == (lhsRecord == rhsRecord))(static_cast<void> (0));
5417
5418 // Unions are never base classes, and never have base classes.
5419 // It doesn't matter if they are complete or not. See PR#41843
5420 if (lhsRecord && lhsRecord->getDecl()->isUnion())
5421 return false;
5422 if (rhsRecord && rhsRecord->getDecl()->isUnion())
5423 return false;
5424
5425 if (lhsRecord == rhsRecord)
5426 return true;
5427
5428 // C++0x [meta.rel]p2:
5429 // If Base and Derived are class types and are different types
5430 // (ignoring possible cv-qualifiers) then Derived shall be a
5431 // complete type.
5432 if (Self.RequireCompleteType(KeyLoc, RhsT,
5433 diag::err_incomplete_type_used_in_type_trait_expr))
5434 return false;
5435
5436 return cast<CXXRecordDecl>(rhsRecord->getDecl())
5437 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
5438 }
5439 case BTT_IsSame:
5440 return Self.Context.hasSameType(LhsT, RhsT);
5441 case BTT_TypeCompatible: {
5442 // GCC ignores cv-qualifiers on arrays for this builtin.
5443 Qualifiers LhsQuals, RhsQuals;
5444 QualType Lhs = Self.getASTContext().getUnqualifiedArrayType(LhsT, LhsQuals);
5445 QualType Rhs = Self.getASTContext().getUnqualifiedArrayType(RhsT, RhsQuals);
5446 return Self.Context.typesAreCompatible(Lhs, Rhs);
5447 }
5448 case BTT_IsConvertible:
5449 case BTT_IsConvertibleTo: {
5450 // C++0x [meta.rel]p4:
5451 // Given the following function prototype:
5452 //
5453 // template <class T>
5454 // typename add_rvalue_reference<T>::type create();
5455 //
5456 // the predicate condition for a template specialization
5457 // is_convertible<From, To> shall be satisfied if and only if
5458 // the return expression in the following code would be
5459 // well-formed, including any implicit conversions to the return
5460 // type of the function:
5461 //
5462 // To test() {
5463 // return create<From>();
5464 // }
5465 //
5466 // Access checking is performed as if in a context unrelated to To and
5467 // From. Only the validity of the immediate context of the expression
5468 // of the return-statement (including conversions to the return type)
5469 // is considered.
5470 //
5471 // We model the initialization as a copy-initialization of a temporary
5472 // of the appropriate type, which for this expression is identical to the
5473 // return statement (since NRVO doesn't apply).
5474
5475 // Functions aren't allowed to return function or array types.
5476 if (RhsT->isFunctionType() || RhsT->isArrayType())
5477 return false;
5478
5479 // A return statement in a void function must have void type.
5480 if (RhsT->isVoidType())
5481 return LhsT->isVoidType();
5482
5483 // A function definition requires a complete, non-abstract return type.
5484 if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
5485 return false;
5486
5487 // Compute the result of add_rvalue_reference.
5488 if (LhsT->isObjectType() || LhsT->isFunctionType())
5489 LhsT = Self.Context.getRValueReferenceType(LhsT);
5490
5491 // Build a fake source and destination for initialization.
5492 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
5493 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5494 Expr::getValueKindForType(LhsT));
5495 Expr *FromPtr = &From;
5496 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
5497 SourceLocation()));
5498
5499 // Perform the initialization in an unevaluated context within a SFINAE
5500 // trap at translation unit scope.
5501 EnterExpressionEvaluationContext Unevaluated(
5502 Self, Sema::ExpressionEvaluationContext::Unevaluated);
5503 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5504 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5505 InitializationSequence Init(Self, To, Kind, FromPtr);
5506 if (Init.Failed())
5507 return false;
5508
5509 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
5510 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
5511 }
5512
5513 case BTT_IsAssignable:
5514 case BTT_IsNothrowAssignable:
5515 case BTT_IsTriviallyAssignable: {
5516 // C++11 [meta.unary.prop]p3:
5517 // is_trivially_assignable is defined as:
5518 // is_assignable<T, U>::value is true and the assignment, as defined by
5519 // is_assignable, is known to call no operation that is not trivial
5520 //
5521 // is_assignable is defined as:
5522 // The expression declval<T>() = declval<U>() is well-formed when
5523 // treated as an unevaluated operand (Clause 5).
5524 //
5525 // For both, T and U shall be complete types, (possibly cv-qualified)
5526 // void, or arrays of unknown bound.
5527 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
5528 Self.RequireCompleteType(KeyLoc, LhsT,
5529 diag::err_incomplete_type_used_in_type_trait_expr))
5530 return false;
5531 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
5532 Self.RequireCompleteType(KeyLoc, RhsT,
5533 diag::err_incomplete_type_used_in_type_trait_expr))
5534 return false;
5535
5536 // cv void is never assignable.
5537 if (LhsT->isVoidType() || RhsT->isVoidType())
5538 return false;
5539
5540 // Build expressions that emulate the effect of declval<T>() and
5541 // declval<U>().
5542 if (LhsT->isObjectType() || LhsT->isFunctionType())
5543 LhsT = Self.Context.getRValueReferenceType(LhsT);
5544 if (RhsT->isObjectType() || RhsT->isFunctionType())
5545 RhsT = Self.Context.getRValueReferenceType(RhsT);
5546 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5547 Expr::getValueKindForType(LhsT));
5548 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
5549 Expr::getValueKindForType(RhsT));
5550
5551 // Attempt the assignment in an unevaluated context within a SFINAE
5552 // trap at translation unit scope.
5553 EnterExpressionEvaluationContext Unevaluated(
5554 Self, Sema::ExpressionEvaluationContext::Unevaluated);
5555 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5556 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5557 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
5558 &Rhs);
5559 if (Result.isInvalid())
5560 return false;
5561
5562 // Treat the assignment as unused for the purpose of -Wdeprecated-volatile.
5563 Self.CheckUnusedVolatileAssignment(Result.get());
5564
5565 if (SFINAE.hasErrorOccurred())
5566 return false;
5567
5568 if (BTT == BTT_IsAssignable)
5569 return true;
5570
5571 if (BTT == BTT_IsNothrowAssignable)
5572 return Self.canThrow(Result.get()) == CT_Cannot;
5573
5574 if (BTT == BTT_IsTriviallyAssignable) {
5575 // Under Objective-C ARC and Weak, if the destination has non-trivial
5576 // Objective-C lifetime, this is a non-trivial assignment.
5577 if (LhsT.getNonReferenceType().hasNonTrivialObjCLifetime())
5578 return false;
5579
5580 return !Result.get()->hasNonTrivialCall(Self.Context);
5581 }
5582
5583 llvm_unreachable("unhandled type trait")__builtin_unreachable();
5584 return false;
5585 }
5586 default: llvm_unreachable("not a BTT")__builtin_unreachable();
5587 }
5588 llvm_unreachable("Unknown type trait or not implemented")__builtin_unreachable();
5589}
5590
5591ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
5592 SourceLocation KWLoc,
5593 ParsedType Ty,
5594 Expr* DimExpr,
5595 SourceLocation RParen) {
5596 TypeSourceInfo *TSInfo;
5597 QualType T = GetTypeFromParser(Ty, &TSInfo);
5598 if (!TSInfo)
5599 TSInfo = Context.getTrivialTypeSourceInfo(T);
5600
5601 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
5602}
5603
5604static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
5605 QualType T, Expr *DimExpr,
5606 SourceLocation KeyLoc) {
5607 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type")(static_cast<void> (0));
5608
5609 switch(ATT) {
5610 case ATT_ArrayRank:
5611 if (T->isArrayType()) {
5612 unsigned Dim = 0;
5613 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5614 ++Dim;
5615 T = AT->getElementType();
5616 }
5617 return Dim;
5618 }
5619 return 0;
5620
5621 case ATT_ArrayExtent: {
5622 llvm::APSInt Value;
5623 uint64_t Dim;
5624 if (Self.VerifyIntegerConstantExpression(
5625 DimExpr, &Value, diag::err_dimension_expr_not_constant_integer)
5626 .isInvalid())
5627 return 0;
5628 if (Value.isSigned() && Value.isNegative()) {
5629 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
5630 << DimExpr->getSourceRange();
5631 return 0;
5632 }
5633 Dim = Value.getLimitedValue();
5634
5635 if (T->isArrayType()) {
5636 unsigned D = 0;
5637 bool Matched = false;
5638 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5639 if (Dim == D) {
5640 Matched = true;
5641 break;
5642 }
5643 ++D;
5644 T = AT->getElementType();
5645 }
5646
5647 if (Matched && T->isArrayType()) {
5648 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
5649 return CAT->getSize().getLimitedValue();
5650 }
5651 }
5652 return 0;
5653 }
5654 }
5655 llvm_unreachable("Unknown type trait or not implemented")__builtin_unreachable();
5656}
5657
5658ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
5659 SourceLocation KWLoc,
5660 TypeSourceInfo *TSInfo,
5661 Expr* DimExpr,
5662 SourceLocation RParen) {
5663 QualType T = TSInfo->getType();
5664
5665 // FIXME: This should likely be tracked as an APInt to remove any host
5666 // assumptions about the width of size_t on the target.
5667 uint64_t Value = 0;
5668 if (!T->isDependentType())
5669 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
5670
5671 // While the specification for these traits from the Embarcadero C++
5672 // compiler's documentation says the return type is 'unsigned int', Clang
5673 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
5674 // compiler, there is no difference. On several other platforms this is an
5675 // important distinction.
5676 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
5677 RParen, Context.getSizeType());
5678}
5679
5680ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
5681 SourceLocation KWLoc,
5682 Expr *Queried,
5683 SourceLocation RParen) {
5684 // If error parsing the expression, ignore.
5685 if (!Queried)
5686 return ExprError();
5687
5688 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
5689
5690 return Result;
5691}
5692
5693static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
5694 switch (ET) {
5695 case ET_IsLValueExpr: return E->isLValue();
5696 case ET_IsRValueExpr:
5697 return E->isPRValue();
5698 }
5699 llvm_unreachable("Expression trait not covered by switch")__builtin_unreachable();
5700}
5701
5702ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
5703 SourceLocation KWLoc,
5704 Expr *Queried,
5705 SourceLocation RParen) {
5706 if (Queried->isTypeDependent()) {
5707 // Delay type-checking for type-dependent expressions.
5708 } else if (Queried->getType()->isPlaceholderType()) {
5709 ExprResult PE = CheckPlaceholderExpr(Queried);
5710 if (PE.isInvalid()) return ExprError();
5711 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
5712 }
5713
5714 bool Value = EvaluateExpressionTrait(ET, Queried);
5715
5716 return new (Context)
5717 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
5718}
5719
5720QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
5721 ExprValueKind &VK,
5722 SourceLocation Loc,
5723 bool isIndirect) {
5724 assert(!LHS.get()->getType()->isPlaceholderType() &&(static_cast<void> (0))
5725 !RHS.get()->getType()->isPlaceholderType() &&(static_cast<void> (0))
5726 "placeholders should have been weeded out by now")(static_cast<void> (0));
5727
5728 // The LHS undergoes lvalue conversions if this is ->*, and undergoes the
5729 // temporary materialization conversion otherwise.
5730 if (isIndirect)
5731 LHS = DefaultLvalueConversion(LHS.get());
5732 else if (LHS.get()->isPRValue())
5733 LHS = TemporaryMaterializationConversion(LHS.get());
5734 if (LHS.isInvalid())
5735 return QualType();
5736
5737 // The RHS always undergoes lvalue conversions.
5738 RHS = DefaultLvalueConversion(RHS.get());
5739 if (RHS.isInvalid()) return QualType();
5740
5741 const char *OpSpelling = isIndirect ? "->*" : ".*";
5742 // C++ 5.5p2
5743 // The binary operator .* [p3: ->*] binds its second operand, which shall
5744 // be of type "pointer to member of T" (where T is a completely-defined
5745 // class type) [...]
5746 QualType RHSType = RHS.get()->getType();
5747 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
5748 if (!MemPtr) {
5749 Diag(Loc, diag::err_bad_memptr_rhs)
5750 << OpSpelling << RHSType << RHS.get()->getSourceRange();
5751 return QualType();
5752 }
5753
5754 QualType Class(MemPtr->getClass(), 0);
5755
5756 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
5757 // member pointer points must be completely-defined. However, there is no
5758 // reason for this semantic distinction, and the rule is not enforced by
5759 // other compilers. Therefore, we do not check this property, as it is
5760 // likely to be considered a defect.
5761
5762 // C++ 5.5p2
5763 // [...] to its first operand, which shall be of class T or of a class of
5764 // which T is an unambiguous and accessible base class. [p3: a pointer to
5765 // such a class]
5766 QualType LHSType = LHS.get()->getType();
5767 if (isIndirect) {
5768 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
5769 LHSType = Ptr->getPointeeType();
5770 else {
5771 Diag(Loc, diag::err_bad_memptr_lhs)
5772 << OpSpelling << 1 << LHSType
5773 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
5774 return QualType();
5775 }
5776 }
5777
5778 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
5779 // If we want to check the hierarchy, we need a complete type.
5780 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
5781 OpSpelling, (int)isIndirect)) {
5782 return QualType();
5783 }
5784
5785 if (!IsDerivedFrom(Loc, LHSType, Class)) {
5786 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
5787 << (int)isIndirect << LHS.get()->getType();
5788 return QualType();
5789 }
5790
5791 CXXCastPath BasePath;
5792 if (CheckDerivedToBaseConversion(
5793 LHSType, Class, Loc,
5794 SourceRange(LHS.get()->getBeginLoc(), RHS.get()->getEndLoc()),
5795 &BasePath))
5796 return QualType();
5797
5798 // Cast LHS to type of use.
5799 QualType UseType = Context.getQualifiedType(Class, LHSType.getQualifiers());
5800 if (isIndirect)
5801 UseType = Context.getPointerType(UseType);
5802 ExprValueKind VK = isIndirect ? VK_PRValue : LHS.get()->getValueKind();
5803 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
5804 &BasePath);
5805 }
5806
5807 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
5808 // Diagnose use of pointer-to-member type which when used as
5809 // the functional cast in a pointer-to-member expression.
5810 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
5811 return QualType();
5812 }
5813
5814 // C++ 5.5p2
5815 // The result is an object or a function of the type specified by the
5816 // second operand.
5817 // The cv qualifiers are the union of those in the pointer and the left side,
5818 // in accordance with 5.5p5 and 5.2.5.
5819 QualType Result = MemPtr->getPointeeType();
5820 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
5821
5822 // C++0x [expr.mptr.oper]p6:
5823 // In a .* expression whose object expression is an rvalue, the program is
5824 // ill-formed if the second operand is a pointer to member function with
5825 // ref-qualifier &. In a ->* expression or in a .* expression whose object
5826 // expression is an lvalue, the program is ill-formed if the second operand
5827 // is a pointer to member function with ref-qualifier &&.
5828 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
5829 switch (Proto->getRefQualifier()) {
5830 case RQ_None:
5831 // Do nothing
5832 break;
5833
5834 case RQ_LValue:
5835 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) {
5836 // C++2a allows functions with ref-qualifier & if their cv-qualifier-seq
5837 // is (exactly) 'const'.
5838 if (Proto->isConst() && !Proto->isVolatile())
5839 Diag(Loc, getLangOpts().CPlusPlus20
5840 ? diag::warn_cxx17_compat_pointer_to_const_ref_member_on_rvalue
5841 : diag::ext_pointer_to_const_ref_member_on_rvalue);
5842 else
5843 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5844 << RHSType << 1 << LHS.get()->getSourceRange();
5845 }
5846 break;
5847
5848 case RQ_RValue:
5849 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
5850 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5851 << RHSType << 0 << LHS.get()->getSourceRange();
5852 break;
5853 }
5854 }
5855
5856 // C++ [expr.mptr.oper]p6:
5857 // The result of a .* expression whose second operand is a pointer
5858 // to a data member is of the same value category as its
5859 // first operand. The result of a .* expression whose second
5860 // operand is a pointer to a member function is a prvalue. The
5861 // result of an ->* expression is an lvalue if its second operand
5862 // is a pointer to data member and a prvalue otherwise.
5863 if (Result->isFunctionType()) {
5864 VK = VK_PRValue;
5865 return Context.BoundMemberTy;
5866 } else if (isIndirect) {
5867 VK = VK_LValue;
5868 } else {
5869 VK = LHS.get()->getValueKind();
5870 }
5871
5872 return Result;
5873}
5874
5875/// Try to convert a type to another according to C++11 5.16p3.
5876///
5877/// This is part of the parameter validation for the ? operator. If either
5878/// value operand is a class type, the two operands are attempted to be
5879/// converted to each other. This function does the conversion in one direction.
5880/// It returns true if the program is ill-formed and has already been diagnosed
5881/// as such.
5882static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
5883 SourceLocation QuestionLoc,
5884 bool &HaveConversion,
5885 QualType &ToType) {
5886 HaveConversion = false;
5887 ToType = To->getType();
5888
5889 InitializationKind Kind =
5890 InitializationKind::CreateCopy(To->getBeginLoc(), SourceLocation());
5891 // C++11 5.16p3
5892 // The process for determining whether an operand expression E1 of type T1
5893 // can be converted to match an operand expression E2 of type T2 is defined
5894 // as follows:
5895 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
5896 // implicitly converted to type "lvalue reference to T2", subject to the
5897 // constraint that in the conversion the reference must bind directly to
5898 // an lvalue.
5899 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
5900 // implicitly converted to the type "rvalue reference to R2", subject to
5901 // the constraint that the reference must bind directly.
5902 if (To->isGLValue()) {
5903 QualType T = Self.Context.getReferenceQualifiedType(To);
5904 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5905
5906 InitializationSequence InitSeq(Self, Entity, Kind, From);
5907 if (InitSeq.isDirectReferenceBinding()) {
5908 ToType = T;
5909 HaveConversion = true;
5910 return false;
5911 }
5912
5913 if (InitSeq.isAmbiguous())
5914 return InitSeq.Diagnose(Self, Entity, Kind, From);
5915 }
5916
5917 // -- If E2 is an rvalue, or if the conversion above cannot be done:
5918 // -- if E1 and E2 have class type, and the underlying class types are
5919 // the same or one is a base class of the other:
5920 QualType FTy = From->getType();
5921 QualType TTy = To->getType();
5922 const RecordType *FRec = FTy->getAs<RecordType>();
5923 const RecordType *TRec = TTy->getAs<RecordType>();
5924 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
5925 Self.IsDerivedFrom(QuestionLoc, FTy, TTy);
5926 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
5927 Self.IsDerivedFrom(QuestionLoc, TTy, FTy))) {
5928 // E1 can be converted to match E2 if the class of T2 is the
5929 // same type as, or a base class of, the class of T1, and
5930 // [cv2 > cv1].
5931 if (FRec == TRec || FDerivedFromT) {
5932 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
5933 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5934 InitializationSequence InitSeq(Self, Entity, Kind, From);
5935 if (InitSeq) {
5936 HaveConversion = true;
5937 return false;
5938 }
5939
5940 if (InitSeq.isAmbiguous())
5941 return InitSeq.Diagnose(Self, Entity, Kind, From);
5942 }
5943 }
5944
5945 return false;
5946 }
5947
5948 // -- Otherwise: E1 can be converted to match E2 if E1 can be
5949 // implicitly converted to the type that expression E2 would have
5950 // if E2 were converted to an rvalue (or the type it has, if E2 is
5951 // an rvalue).
5952 //
5953 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
5954 // to the array-to-pointer or function-to-pointer conversions.
5955 TTy = TTy.getNonLValueExprType(Self.Context);
5956
5957 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5958 InitializationSequence InitSeq(Self, Entity, Kind, From);
5959 HaveConversion = !InitSeq.Failed();
5960 ToType = TTy;
5961 if (InitSeq.isAmbiguous())
5962 return InitSeq.Diagnose(Self, Entity, Kind, From);
5963
5964 return false;
5965}
5966
5967/// Try to find a common type for two according to C++0x 5.16p5.
5968///
5969/// This is part of the parameter validation for the ? operator. If either
5970/// value operand is a class type, overload resolution is used to find a
5971/// conversion to a common type.
5972static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
5973 SourceLocation QuestionLoc) {
5974 Expr *Args[2] = { LHS.get(), RHS.get() };
5975 OverloadCandidateSet CandidateSet(QuestionLoc,
5976 OverloadCandidateSet::CSK_Operator);
5977 Self.AddBuiltinOperatorCandidates(OO_Conditional,