1 //===--- SemaExceptionSpec.cpp - C++ Exception Specifications ---*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file provides Sema routines for C++ exception specification testing.
11 //===----------------------------------------------------------------------===//
13 #include "clang/Sema/SemaInternal.h"
14 #include "clang/AST/ASTMutationListener.h"
15 #include "clang/AST/CXXInheritance.h"
16 #include "clang/AST/Expr.h"
17 #include "clang/AST/ExprCXX.h"
18 #include "clang/AST/TypeLoc.h"
19 #include "clang/Basic/Diagnostic.h"
20 #include "clang/Basic/SourceManager.h"
21 #include "llvm/ADT/SmallPtrSet.h"
22 #include "llvm/ADT/SmallString.h"
26 static const FunctionProtoType *GetUnderlyingFunction(QualType T)
28 if (const PointerType *PtrTy = T->getAs<PointerType>())
29 T = PtrTy->getPointeeType();
30 else if (const ReferenceType *RefTy = T->getAs<ReferenceType>())
31 T = RefTy->getPointeeType();
32 else if (const MemberPointerType *MPTy = T->getAs<MemberPointerType>())
33 T = MPTy->getPointeeType();
34 return T->getAs<FunctionProtoType>();
37 /// HACK: libstdc++ has a bug where it shadows std::swap with a member
38 /// swap function then tries to call std::swap unqualified from the exception
39 /// specification of that function. This function detects whether we're in
40 /// such a case and turns off delay-parsing of exception specifications.
41 bool Sema::isLibstdcxxEagerExceptionSpecHack(const Declarator &D) {
42 auto *RD = dyn_cast<CXXRecordDecl>(CurContext);
44 // All the problem cases are member functions named "swap" within class
45 // templates declared directly within namespace std or std::__debug or
47 if (!RD || !RD->getIdentifier() || !RD->getDescribedClassTemplate() ||
48 !D.getIdentifier() || !D.getIdentifier()->isStr("swap"))
51 auto *ND = dyn_cast<NamespaceDecl>(RD->getDeclContext());
55 bool IsInStd = ND->isStdNamespace();
57 // This isn't a direct member of namespace std, but it might still be
58 // libstdc++'s std::__debug::array or std::__profile::array.
59 IdentifierInfo *II = ND->getIdentifier();
60 if (!II || !(II->isStr("__debug") || II->isStr("__profile")) ||
61 !ND->isInStdNamespace())
65 // Only apply this hack within a system header.
66 if (!Context.getSourceManager().isInSystemHeader(D.getBeginLoc()))
69 return llvm::StringSwitch<bool>(RD->getIdentifier()->getName())
71 .Case("pair", IsInStd)
72 .Case("priority_queue", IsInStd)
73 .Case("stack", IsInStd)
74 .Case("queue", IsInStd)
78 ExprResult Sema::ActOnNoexceptSpec(SourceLocation NoexceptLoc,
80 ExceptionSpecificationType &EST) {
81 // FIXME: This is bogus, a noexcept expression is not a condition.
82 ExprResult Converted = CheckBooleanCondition(NoexceptLoc, NoexceptExpr);
83 if (Converted.isInvalid())
86 if (Converted.get()->isValueDependent()) {
87 EST = EST_DependentNoexcept;
92 Converted = VerifyIntegerConstantExpression(
93 Converted.get(), &Result,
94 diag::err_noexcept_needs_constant_expression,
96 if (!Converted.isInvalid())
97 EST = !Result ? EST_NoexceptFalse : EST_NoexceptTrue;
101 /// CheckSpecifiedExceptionType - Check if the given type is valid in an
102 /// exception specification. Incomplete types, or pointers to incomplete types
103 /// other than void are not allowed.
105 /// \param[in,out] T The exception type. This will be decayed to a pointer type
106 /// when the input is an array or a function type.
107 bool Sema::CheckSpecifiedExceptionType(QualType &T, SourceRange Range) {
108 // C++11 [except.spec]p2:
109 // A type cv T, "array of T", or "function returning T" denoted
110 // in an exception-specification is adjusted to type T, "pointer to T", or
111 // "pointer to function returning T", respectively.
113 // We also apply this rule in C++98.
114 if (T->isArrayType())
115 T = Context.getArrayDecayedType(T);
116 else if (T->isFunctionType())
117 T = Context.getPointerType(T);
120 QualType PointeeT = T;
121 if (const PointerType *PT = T->getAs<PointerType>()) {
122 PointeeT = PT->getPointeeType();
125 // cv void* is explicitly permitted, despite being a pointer to an
127 if (PointeeT->isVoidType())
129 } else if (const ReferenceType *RT = T->getAs<ReferenceType>()) {
130 PointeeT = RT->getPointeeType();
133 if (RT->isRValueReferenceType()) {
134 // C++11 [except.spec]p2:
135 // A type denoted in an exception-specification shall not denote [...]
136 // an rvalue reference type.
137 Diag(Range.getBegin(), diag::err_rref_in_exception_spec)
143 // C++11 [except.spec]p2:
144 // A type denoted in an exception-specification shall not denote an
145 // incomplete type other than a class currently being defined [...].
146 // A type denoted in an exception-specification shall not denote a
147 // pointer or reference to an incomplete type, other than (cv) void* or a
148 // pointer or reference to a class currently being defined.
149 // In Microsoft mode, downgrade this to a warning.
150 unsigned DiagID = diag::err_incomplete_in_exception_spec;
151 bool ReturnValueOnError = true;
152 if (getLangOpts().MicrosoftExt) {
153 DiagID = diag::ext_incomplete_in_exception_spec;
154 ReturnValueOnError = false;
156 if (!(PointeeT->isRecordType() &&
157 PointeeT->getAs<RecordType>()->isBeingDefined()) &&
158 RequireCompleteType(Range.getBegin(), PointeeT, DiagID, Kind, Range))
159 return ReturnValueOnError;
164 /// CheckDistantExceptionSpec - Check if the given type is a pointer or pointer
165 /// to member to a function with an exception specification. This means that
166 /// it is invalid to add another level of indirection.
167 bool Sema::CheckDistantExceptionSpec(QualType T) {
168 // C++17 removes this rule in favor of putting exception specifications into
170 if (getLangOpts().CPlusPlus17)
173 if (const PointerType *PT = T->getAs<PointerType>())
174 T = PT->getPointeeType();
175 else if (const MemberPointerType *PT = T->getAs<MemberPointerType>())
176 T = PT->getPointeeType();
180 const FunctionProtoType *FnT = T->getAs<FunctionProtoType>();
184 return FnT->hasExceptionSpec();
187 const FunctionProtoType *
188 Sema::ResolveExceptionSpec(SourceLocation Loc, const FunctionProtoType *FPT) {
189 if (FPT->getExceptionSpecType() == EST_Unparsed) {
190 Diag(Loc, diag::err_exception_spec_not_parsed);
194 if (!isUnresolvedExceptionSpec(FPT->getExceptionSpecType()))
197 FunctionDecl *SourceDecl = FPT->getExceptionSpecDecl();
198 const FunctionProtoType *SourceFPT =
199 SourceDecl->getType()->castAs<FunctionProtoType>();
201 // If the exception specification has already been resolved, just return it.
202 if (!isUnresolvedExceptionSpec(SourceFPT->getExceptionSpecType()))
205 // Compute or instantiate the exception specification now.
206 if (SourceFPT->getExceptionSpecType() == EST_Unevaluated)
207 EvaluateImplicitExceptionSpec(Loc, cast<CXXMethodDecl>(SourceDecl));
209 InstantiateExceptionSpec(Loc, SourceDecl);
211 const FunctionProtoType *Proto =
212 SourceDecl->getType()->castAs<FunctionProtoType>();
213 if (Proto->getExceptionSpecType() == clang::EST_Unparsed) {
214 Diag(Loc, diag::err_exception_spec_not_parsed);
221 Sema::UpdateExceptionSpec(FunctionDecl *FD,
222 const FunctionProtoType::ExceptionSpecInfo &ESI) {
223 // If we've fully resolved the exception specification, notify listeners.
224 if (!isUnresolvedExceptionSpec(ESI.Type))
225 if (auto *Listener = getASTMutationListener())
226 Listener->ResolvedExceptionSpec(FD);
228 for (FunctionDecl *Redecl : FD->redecls())
229 Context.adjustExceptionSpec(Redecl, ESI);
232 static bool exceptionSpecNotKnownYet(const FunctionDecl *FD) {
233 auto *MD = dyn_cast<CXXMethodDecl>(FD);
237 auto EST = MD->getType()->castAs<FunctionProtoType>()->getExceptionSpecType();
238 return EST == EST_Unparsed ||
239 (EST == EST_Unevaluated && MD->getParent()->isBeingDefined());
242 static bool CheckEquivalentExceptionSpecImpl(
243 Sema &S, const PartialDiagnostic &DiagID, const PartialDiagnostic &NoteID,
244 const FunctionProtoType *Old, SourceLocation OldLoc,
245 const FunctionProtoType *New, SourceLocation NewLoc,
246 bool *MissingExceptionSpecification = nullptr,
247 bool *MissingEmptyExceptionSpecification = nullptr,
248 bool AllowNoexceptAllMatchWithNoSpec = false, bool IsOperatorNew = false);
250 /// Determine whether a function has an implicitly-generated exception
252 static bool hasImplicitExceptionSpec(FunctionDecl *Decl) {
253 if (!isa<CXXDestructorDecl>(Decl) &&
254 Decl->getDeclName().getCXXOverloadedOperator() != OO_Delete &&
255 Decl->getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
258 // For a function that the user didn't declare:
259 // - if this is a destructor, its exception specification is implicit.
260 // - if this is 'operator delete' or 'operator delete[]', the exception
261 // specification is as-if an explicit exception specification was given
262 // (per [basic.stc.dynamic]p2).
263 if (!Decl->getTypeSourceInfo())
264 return isa<CXXDestructorDecl>(Decl);
266 const FunctionProtoType *Ty =
267 Decl->getTypeSourceInfo()->getType()->getAs<FunctionProtoType>();
268 return !Ty->hasExceptionSpec();
271 bool Sema::CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New) {
272 // Just completely ignore this under -fno-exceptions prior to C++17.
273 // In C++17 onwards, the exception specification is part of the type and
274 // we will diagnose mismatches anyway, so it's better to check for them here.
275 if (!getLangOpts().CXXExceptions && !getLangOpts().CPlusPlus17)
278 OverloadedOperatorKind OO = New->getDeclName().getCXXOverloadedOperator();
279 bool IsOperatorNew = OO == OO_New || OO == OO_Array_New;
280 bool MissingExceptionSpecification = false;
281 bool MissingEmptyExceptionSpecification = false;
283 unsigned DiagID = diag::err_mismatched_exception_spec;
284 bool ReturnValueOnError = true;
285 if (getLangOpts().MicrosoftExt) {
286 DiagID = diag::ext_mismatched_exception_spec;
287 ReturnValueOnError = false;
290 // If we're befriending a member function of a class that's currently being
291 // defined, we might not be able to work out its exception specification yet.
292 // If not, defer the check until later.
293 if (exceptionSpecNotKnownYet(Old) || exceptionSpecNotKnownYet(New)) {
294 DelayedEquivalentExceptionSpecChecks.push_back({New, Old});
298 // Check the types as written: they must match before any exception
299 // specification adjustment is applied.
300 if (!CheckEquivalentExceptionSpecImpl(
301 *this, PDiag(DiagID), PDiag(diag::note_previous_declaration),
302 Old->getType()->getAs<FunctionProtoType>(), Old->getLocation(),
303 New->getType()->getAs<FunctionProtoType>(), New->getLocation(),
304 &MissingExceptionSpecification, &MissingEmptyExceptionSpecification,
305 /*AllowNoexceptAllMatchWithNoSpec=*/true, IsOperatorNew)) {
306 // C++11 [except.spec]p4 [DR1492]:
307 // If a declaration of a function has an implicit
308 // exception-specification, other declarations of the function shall
309 // not specify an exception-specification.
310 if (getLangOpts().CPlusPlus11 && getLangOpts().CXXExceptions &&
311 hasImplicitExceptionSpec(Old) != hasImplicitExceptionSpec(New)) {
312 Diag(New->getLocation(), diag::ext_implicit_exception_spec_mismatch)
313 << hasImplicitExceptionSpec(Old);
314 if (Old->getLocation().isValid())
315 Diag(Old->getLocation(), diag::note_previous_declaration);
320 // The failure was something other than an missing exception
321 // specification; return an error, except in MS mode where this is a warning.
322 if (!MissingExceptionSpecification)
323 return ReturnValueOnError;
325 const FunctionProtoType *NewProto =
326 New->getType()->castAs<FunctionProtoType>();
328 // The new function declaration is only missing an empty exception
329 // specification "throw()". If the throw() specification came from a
330 // function in a system header that has C linkage, just add an empty
331 // exception specification to the "new" declaration. Note that C library
332 // implementations are permitted to add these nothrow exception
335 // Likewise if the old function is a builtin.
336 if (MissingEmptyExceptionSpecification && NewProto &&
337 (Old->getLocation().isInvalid() ||
338 Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
339 Old->getBuiltinID()) &&
341 New->setType(Context.getFunctionType(
342 NewProto->getReturnType(), NewProto->getParamTypes(),
343 NewProto->getExtProtoInfo().withExceptionSpec(EST_DynamicNone)));
347 const FunctionProtoType *OldProto =
348 Old->getType()->castAs<FunctionProtoType>();
350 FunctionProtoType::ExceptionSpecInfo ESI = OldProto->getExceptionSpecType();
351 if (ESI.Type == EST_Dynamic) {
352 // FIXME: What if the exceptions are described in terms of the old
353 // prototype's parameters?
354 ESI.Exceptions = OldProto->exceptions();
357 if (ESI.Type == EST_NoexceptFalse)
359 if (ESI.Type == EST_NoexceptTrue)
360 ESI.Type = EST_BasicNoexcept;
362 // For dependent noexcept, we can't just take the expression from the old
363 // prototype. It likely contains references to the old prototype's parameters.
364 if (ESI.Type == EST_DependentNoexcept) {
365 New->setInvalidDecl();
367 // Update the type of the function with the appropriate exception
369 New->setType(Context.getFunctionType(
370 NewProto->getReturnType(), NewProto->getParamTypes(),
371 NewProto->getExtProtoInfo().withExceptionSpec(ESI)));
374 if (getLangOpts().MicrosoftExt && ESI.Type != EST_DependentNoexcept) {
375 // Allow missing exception specifications in redeclarations as an extension.
376 DiagID = diag::ext_ms_missing_exception_specification;
377 ReturnValueOnError = false;
378 } else if (New->isReplaceableGlobalAllocationFunction() &&
379 ESI.Type != EST_DependentNoexcept) {
380 // Allow missing exception specifications in redeclarations as an extension,
381 // when declaring a replaceable global allocation function.
382 DiagID = diag::ext_missing_exception_specification;
383 ReturnValueOnError = false;
384 } else if (ESI.Type == EST_NoThrow) {
385 // Allow missing attribute 'nothrow' in redeclarations, since this is a very
387 DiagID = diag::ext_missing_exception_specification;
388 ReturnValueOnError = false;
390 DiagID = diag::err_missing_exception_specification;
391 ReturnValueOnError = true;
394 // Warn about the lack of exception specification.
395 SmallString<128> ExceptionSpecString;
396 llvm::raw_svector_ostream OS(ExceptionSpecString);
397 switch (OldProto->getExceptionSpecType()) {
398 case EST_DynamicNone:
404 bool OnFirstException = true;
405 for (const auto &E : OldProto->exceptions()) {
406 if (OnFirstException)
407 OnFirstException = false;
411 OS << E.getAsString(getPrintingPolicy());
417 case EST_BasicNoexcept:
421 case EST_DependentNoexcept:
422 case EST_NoexceptFalse:
423 case EST_NoexceptTrue:
425 assert(OldProto->getNoexceptExpr() != nullptr && "Expected non-null Expr");
426 OldProto->getNoexceptExpr()->printPretty(OS, nullptr, getPrintingPolicy());
430 OS <<"__attribute__((nothrow))";
434 case EST_Unevaluated:
435 case EST_Uninstantiated:
437 llvm_unreachable("This spec type is compatible with none.");
440 SourceLocation FixItLoc;
441 if (TypeSourceInfo *TSInfo = New->getTypeSourceInfo()) {
442 TypeLoc TL = TSInfo->getTypeLoc().IgnoreParens();
443 // FIXME: Preserve enough information so that we can produce a correct fixit
444 // location when there is a trailing return type.
445 if (auto FTLoc = TL.getAs<FunctionProtoTypeLoc>())
446 if (!FTLoc.getTypePtr()->hasTrailingReturn())
447 FixItLoc = getLocForEndOfToken(FTLoc.getLocalRangeEnd());
450 if (FixItLoc.isInvalid())
451 Diag(New->getLocation(), DiagID)
454 Diag(New->getLocation(), DiagID)
456 << FixItHint::CreateInsertion(FixItLoc, " " + OS.str().str());
459 if (Old->getLocation().isValid())
460 Diag(Old->getLocation(), diag::note_previous_declaration);
462 return ReturnValueOnError;
465 /// CheckEquivalentExceptionSpec - Check if the two types have equivalent
466 /// exception specifications. Exception specifications are equivalent if
467 /// they allow exactly the same set of exception types. It does not matter how
468 /// that is achieved. See C++ [except.spec]p2.
469 bool Sema::CheckEquivalentExceptionSpec(
470 const FunctionProtoType *Old, SourceLocation OldLoc,
471 const FunctionProtoType *New, SourceLocation NewLoc) {
472 if (!getLangOpts().CXXExceptions)
475 unsigned DiagID = diag::err_mismatched_exception_spec;
476 if (getLangOpts().MicrosoftExt)
477 DiagID = diag::ext_mismatched_exception_spec;
478 bool Result = CheckEquivalentExceptionSpecImpl(
479 *this, PDiag(DiagID), PDiag(diag::note_previous_declaration),
480 Old, OldLoc, New, NewLoc);
482 // In Microsoft mode, mismatching exception specifications just cause a warning.
483 if (getLangOpts().MicrosoftExt)
488 /// CheckEquivalentExceptionSpec - Check if the two types have compatible
489 /// exception specifications. See C++ [except.spec]p3.
491 /// \return \c false if the exception specifications match, \c true if there is
492 /// a problem. If \c true is returned, either a diagnostic has already been
493 /// produced or \c *MissingExceptionSpecification is set to \c true.
494 static bool CheckEquivalentExceptionSpecImpl(
495 Sema &S, const PartialDiagnostic &DiagID, const PartialDiagnostic &NoteID,
496 const FunctionProtoType *Old, SourceLocation OldLoc,
497 const FunctionProtoType *New, SourceLocation NewLoc,
498 bool *MissingExceptionSpecification,
499 bool *MissingEmptyExceptionSpecification,
500 bool AllowNoexceptAllMatchWithNoSpec, bool IsOperatorNew) {
501 if (MissingExceptionSpecification)
502 *MissingExceptionSpecification = false;
504 if (MissingEmptyExceptionSpecification)
505 *MissingEmptyExceptionSpecification = false;
507 Old = S.ResolveExceptionSpec(NewLoc, Old);
510 New = S.ResolveExceptionSpec(NewLoc, New);
514 // C++0x [except.spec]p3: Two exception-specifications are compatible if:
515 // - both are non-throwing, regardless of their form,
516 // - both have the form noexcept(constant-expression) and the constant-
517 // expressions are equivalent,
518 // - both are dynamic-exception-specifications that have the same set of
521 // C++0x [except.spec]p12: An exception-specification is non-throwing if it is
522 // of the form throw(), noexcept, or noexcept(constant-expression) where the
523 // constant-expression yields true.
525 // C++0x [except.spec]p4: If any declaration of a function has an exception-
526 // specifier that is not a noexcept-specification allowing all exceptions,
527 // all declarations [...] of that function shall have a compatible
528 // exception-specification.
530 // That last point basically means that noexcept(false) matches no spec.
531 // It's considered when AllowNoexceptAllMatchWithNoSpec is true.
533 ExceptionSpecificationType OldEST = Old->getExceptionSpecType();
534 ExceptionSpecificationType NewEST = New->getExceptionSpecType();
536 assert(!isUnresolvedExceptionSpec(OldEST) &&
537 !isUnresolvedExceptionSpec(NewEST) &&
538 "Shouldn't see unknown exception specifications here");
540 CanThrowResult OldCanThrow = Old->canThrow();
541 CanThrowResult NewCanThrow = New->canThrow();
543 // Any non-throwing specifications are compatible.
544 if (OldCanThrow == CT_Cannot && NewCanThrow == CT_Cannot)
547 // Any throws-anything specifications are usually compatible.
548 if (OldCanThrow == CT_Can && OldEST != EST_Dynamic &&
549 NewCanThrow == CT_Can && NewEST != EST_Dynamic) {
550 // The exception is that the absence of an exception specification only
551 // matches noexcept(false) for functions, as described above.
552 if (!AllowNoexceptAllMatchWithNoSpec &&
553 ((OldEST == EST_None && NewEST == EST_NoexceptFalse) ||
554 (OldEST == EST_NoexceptFalse && NewEST == EST_None))) {
555 // This is the disallowed case.
561 // C++14 [except.spec]p3:
562 // Two exception-specifications are compatible if [...] both have the form
563 // noexcept(constant-expression) and the constant-expressions are equivalent
564 if (OldEST == EST_DependentNoexcept && NewEST == EST_DependentNoexcept) {
565 llvm::FoldingSetNodeID OldFSN, NewFSN;
566 Old->getNoexceptExpr()->Profile(OldFSN, S.Context, true);
567 New->getNoexceptExpr()->Profile(NewFSN, S.Context, true);
568 if (OldFSN == NewFSN)
572 // Dynamic exception specifications with the same set of adjusted types
574 if (OldEST == EST_Dynamic && NewEST == EST_Dynamic) {
576 // Both have a dynamic exception spec. Collect the first set, then compare
578 llvm::SmallPtrSet<CanQualType, 8> OldTypes, NewTypes;
579 for (const auto &I : Old->exceptions())
580 OldTypes.insert(S.Context.getCanonicalType(I).getUnqualifiedType());
582 for (const auto &I : New->exceptions()) {
583 CanQualType TypePtr = S.Context.getCanonicalType(I).getUnqualifiedType();
584 if (OldTypes.count(TypePtr))
585 NewTypes.insert(TypePtr);
592 if (Success && OldTypes.size() == NewTypes.size())
596 // As a special compatibility feature, under C++0x we accept no spec and
597 // throw(std::bad_alloc) as equivalent for operator new and operator new[].
598 // This is because the implicit declaration changed, but old code would break.
599 if (S.getLangOpts().CPlusPlus11 && IsOperatorNew) {
600 const FunctionProtoType *WithExceptions = nullptr;
601 if (OldEST == EST_None && NewEST == EST_Dynamic)
602 WithExceptions = New;
603 else if (OldEST == EST_Dynamic && NewEST == EST_None)
604 WithExceptions = Old;
605 if (WithExceptions && WithExceptions->getNumExceptions() == 1) {
606 // One has no spec, the other throw(something). If that something is
607 // std::bad_alloc, all conditions are met.
608 QualType Exception = *WithExceptions->exception_begin();
609 if (CXXRecordDecl *ExRecord = Exception->getAsCXXRecordDecl()) {
610 IdentifierInfo* Name = ExRecord->getIdentifier();
611 if (Name && Name->getName() == "bad_alloc") {
612 // It's called bad_alloc, but is it in std?
613 if (ExRecord->isInStdNamespace()) {
621 // If the caller wants to handle the case that the new function is
622 // incompatible due to a missing exception specification, let it.
623 if (MissingExceptionSpecification && OldEST != EST_None &&
624 NewEST == EST_None) {
625 // The old type has an exception specification of some sort, but
626 // the new type does not.
627 *MissingExceptionSpecification = true;
629 if (MissingEmptyExceptionSpecification && OldCanThrow == CT_Cannot) {
630 // The old type has a throw() or noexcept(true) exception specification
631 // and the new type has no exception specification, and the caller asked
632 // to handle this itself.
633 *MissingEmptyExceptionSpecification = true;
639 S.Diag(NewLoc, DiagID);
640 if (NoteID.getDiagID() != 0 && OldLoc.isValid())
641 S.Diag(OldLoc, NoteID);
645 bool Sema::CheckEquivalentExceptionSpec(const PartialDiagnostic &DiagID,
646 const PartialDiagnostic &NoteID,
647 const FunctionProtoType *Old,
648 SourceLocation OldLoc,
649 const FunctionProtoType *New,
650 SourceLocation NewLoc) {
651 if (!getLangOpts().CXXExceptions)
653 return CheckEquivalentExceptionSpecImpl(*this, DiagID, NoteID, Old, OldLoc,
657 bool Sema::handlerCanCatch(QualType HandlerType, QualType ExceptionType) {
658 // [except.handle]p3:
659 // A handler is a match for an exception object of type E if:
661 // HandlerType must be ExceptionType or derived from it, or pointer or
662 // reference to such types.
663 const ReferenceType *RefTy = HandlerType->getAs<ReferenceType>();
665 HandlerType = RefTy->getPointeeType();
667 // -- the handler is of type cv T or cv T& and E and T are the same type
668 if (Context.hasSameUnqualifiedType(ExceptionType, HandlerType))
671 // FIXME: ObjC pointer types?
672 if (HandlerType->isPointerType() || HandlerType->isMemberPointerType()) {
673 if (RefTy && (!HandlerType.isConstQualified() ||
674 HandlerType.isVolatileQualified()))
677 // -- the handler is of type cv T or const T& where T is a pointer or
678 // pointer to member type and E is std::nullptr_t
679 if (ExceptionType->isNullPtrType())
682 // -- the handler is of type cv T or const T& where T is a pointer or
683 // pointer to member type and E is a pointer or pointer to member type
684 // that can be converted to T by one or more of
685 // -- a qualification conversion
686 // -- a function pointer conversion
689 // FIXME: Should we treat the exception as catchable if a lifetime
690 // conversion is required?
691 if (IsQualificationConversion(ExceptionType, HandlerType, false,
693 IsFunctionConversion(ExceptionType, HandlerType, Result))
696 // -- a standard pointer conversion [...]
697 if (!ExceptionType->isPointerType() || !HandlerType->isPointerType())
700 // Handle the "qualification conversion" portion.
701 Qualifiers EQuals, HQuals;
702 ExceptionType = Context.getUnqualifiedArrayType(
703 ExceptionType->getPointeeType(), EQuals);
704 HandlerType = Context.getUnqualifiedArrayType(
705 HandlerType->getPointeeType(), HQuals);
706 if (!HQuals.compatiblyIncludes(EQuals))
709 if (HandlerType->isVoidType() && ExceptionType->isObjectType())
712 // The only remaining case is a derived-to-base conversion.
715 // -- the handler is of type cg T or cv T& and T is an unambiguous public
717 if (!ExceptionType->isRecordType() || !HandlerType->isRecordType())
719 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
720 /*DetectVirtual=*/false);
721 if (!IsDerivedFrom(SourceLocation(), ExceptionType, HandlerType, Paths) ||
722 Paths.isAmbiguous(Context.getCanonicalType(HandlerType)))
725 // Do this check from a context without privileges.
726 switch (CheckBaseClassAccess(SourceLocation(), HandlerType, ExceptionType,
730 /*ForceUnprivileged*/ true)) {
731 case AR_accessible: return true;
732 case AR_inaccessible: return false;
734 llvm_unreachable("access check dependent for unprivileged context");
736 llvm_unreachable("access check delayed in non-declaration");
738 llvm_unreachable("unexpected access check result");
741 /// CheckExceptionSpecSubset - Check whether the second function type's
742 /// exception specification is a subset (or equivalent) of the first function
743 /// type. This is used by override and pointer assignment checks.
744 bool Sema::CheckExceptionSpecSubset(const PartialDiagnostic &DiagID,
745 const PartialDiagnostic &NestedDiagID,
746 const PartialDiagnostic &NoteID,
747 const PartialDiagnostic &NoThrowDiagID,
748 const FunctionProtoType *Superset,
749 SourceLocation SuperLoc,
750 const FunctionProtoType *Subset,
751 SourceLocation SubLoc) {
753 // Just auto-succeed under -fno-exceptions.
754 if (!getLangOpts().CXXExceptions)
757 // FIXME: As usual, we could be more specific in our error messages, but
758 // that better waits until we've got types with source locations.
760 if (!SubLoc.isValid())
763 // Resolve the exception specifications, if needed.
764 Superset = ResolveExceptionSpec(SuperLoc, Superset);
767 Subset = ResolveExceptionSpec(SubLoc, Subset);
771 ExceptionSpecificationType SuperEST = Superset->getExceptionSpecType();
772 ExceptionSpecificationType SubEST = Subset->getExceptionSpecType();
773 assert(!isUnresolvedExceptionSpec(SuperEST) &&
774 !isUnresolvedExceptionSpec(SubEST) &&
775 "Shouldn't see unknown exception specifications here");
777 // If there are dependent noexcept specs, assume everything is fine. Unlike
778 // with the equivalency check, this is safe in this case, because we don't
779 // want to merge declarations. Checks after instantiation will catch any
780 // omissions we make here.
781 if (SuperEST == EST_DependentNoexcept || SubEST == EST_DependentNoexcept)
784 CanThrowResult SuperCanThrow = Superset->canThrow();
785 CanThrowResult SubCanThrow = Subset->canThrow();
787 // If the superset contains everything or the subset contains nothing, we're
789 if ((SuperCanThrow == CT_Can && SuperEST != EST_Dynamic) ||
790 SubCanThrow == CT_Cannot)
791 return CheckParamExceptionSpec(NestedDiagID, NoteID, Superset, SuperLoc,
794 // Allow __declspec(nothrow) to be missing on redeclaration as an extension in
796 if (NoThrowDiagID.getDiagID() != 0 && SubCanThrow == CT_Can &&
797 SuperCanThrow == CT_Cannot && SuperEST == EST_NoThrow) {
798 Diag(SubLoc, NoThrowDiagID);
799 if (NoteID.getDiagID() != 0)
800 Diag(SuperLoc, NoteID);
804 // If the subset contains everything or the superset contains nothing, we've
806 if ((SubCanThrow == CT_Can && SubEST != EST_Dynamic) ||
807 SuperCanThrow == CT_Cannot) {
808 Diag(SubLoc, DiagID);
809 if (NoteID.getDiagID() != 0)
810 Diag(SuperLoc, NoteID);
814 assert(SuperEST == EST_Dynamic && SubEST == EST_Dynamic &&
815 "Exception spec subset: non-dynamic case slipped through.");
817 // Neither contains everything or nothing. Do a proper comparison.
818 for (QualType SubI : Subset->exceptions()) {
819 if (const ReferenceType *RefTy = SubI->getAs<ReferenceType>())
820 SubI = RefTy->getPointeeType();
822 // Make sure it's in the superset.
823 bool Contained = false;
824 for (QualType SuperI : Superset->exceptions()) {
826 // the target entity shall allow at least the exceptions allowed by the
829 // We interpret this as meaning that a handler for some target type would
830 // catch an exception of each source type.
831 if (handlerCanCatch(SuperI, SubI)) {
837 Diag(SubLoc, DiagID);
838 if (NoteID.getDiagID() != 0)
839 Diag(SuperLoc, NoteID);
843 // We've run half the gauntlet.
844 return CheckParamExceptionSpec(NestedDiagID, NoteID, Superset, SuperLoc,
849 CheckSpecForTypesEquivalent(Sema &S, const PartialDiagnostic &DiagID,
850 const PartialDiagnostic &NoteID, QualType Target,
851 SourceLocation TargetLoc, QualType Source,
852 SourceLocation SourceLoc) {
853 const FunctionProtoType *TFunc = GetUnderlyingFunction(Target);
856 const FunctionProtoType *SFunc = GetUnderlyingFunction(Source);
860 return S.CheckEquivalentExceptionSpec(DiagID, NoteID, TFunc, TargetLoc,
864 /// CheckParamExceptionSpec - Check if the parameter and return types of the
865 /// two functions have equivalent exception specs. This is part of the
866 /// assignment and override compatibility check. We do not check the parameters
867 /// of parameter function pointers recursively, as no sane programmer would
868 /// even be able to write such a function type.
869 bool Sema::CheckParamExceptionSpec(const PartialDiagnostic &DiagID,
870 const PartialDiagnostic &NoteID,
871 const FunctionProtoType *Target,
872 SourceLocation TargetLoc,
873 const FunctionProtoType *Source,
874 SourceLocation SourceLoc) {
875 auto RetDiag = DiagID;
877 if (CheckSpecForTypesEquivalent(
878 *this, RetDiag, PDiag(),
879 Target->getReturnType(), TargetLoc, Source->getReturnType(),
883 // We shouldn't even be testing this unless the arguments are otherwise
885 assert(Target->getNumParams() == Source->getNumParams() &&
886 "Functions have different argument counts.");
887 for (unsigned i = 0, E = Target->getNumParams(); i != E; ++i) {
888 auto ParamDiag = DiagID;
890 if (CheckSpecForTypesEquivalent(
891 *this, ParamDiag, PDiag(),
892 Target->getParamType(i), TargetLoc, Source->getParamType(i),
899 bool Sema::CheckExceptionSpecCompatibility(Expr *From, QualType ToType) {
900 // First we check for applicability.
901 // Target type must be a function, function pointer or function reference.
902 const FunctionProtoType *ToFunc = GetUnderlyingFunction(ToType);
903 if (!ToFunc || ToFunc->hasDependentExceptionSpec())
906 // SourceType must be a function or function pointer.
907 const FunctionProtoType *FromFunc = GetUnderlyingFunction(From->getType());
908 if (!FromFunc || FromFunc->hasDependentExceptionSpec())
911 unsigned DiagID = diag::err_incompatible_exception_specs;
912 unsigned NestedDiagID = diag::err_deep_exception_specs_differ;
913 // This is not an error in C++17 onwards, unless the noexceptness doesn't
914 // match, but in that case we have a full-on type mismatch, not just a
915 // type sugar mismatch.
916 if (getLangOpts().CPlusPlus17) {
917 DiagID = diag::warn_incompatible_exception_specs;
918 NestedDiagID = diag::warn_deep_exception_specs_differ;
921 // Now we've got the correct types on both sides, check their compatibility.
922 // This means that the source of the conversion can only throw a subset of
923 // the exceptions of the target, and any exception specs on arguments or
924 // return types must be equivalent.
926 // FIXME: If there is a nested dependent exception specification, we should
927 // not be checking it here. This is fine:
928 // template<typename T> void f() {
929 // void (*p)(void (*) throw(T));
930 // void (*q)(void (*) throw(int)) = p;
932 // ... because it might be instantiated with T=int.
933 return CheckExceptionSpecSubset(
934 PDiag(DiagID), PDiag(NestedDiagID), PDiag(), PDiag(), ToFunc,
935 From->getSourceRange().getBegin(), FromFunc, SourceLocation()) &&
936 !getLangOpts().CPlusPlus17;
939 bool Sema::CheckOverridingFunctionExceptionSpec(const CXXMethodDecl *New,
940 const CXXMethodDecl *Old) {
941 // If the new exception specification hasn't been parsed yet, skip the check.
942 // We'll get called again once it's been parsed.
943 if (New->getType()->castAs<FunctionProtoType>()->getExceptionSpecType() ==
947 // Don't check uninstantiated template destructors at all. We can only
948 // synthesize correct specs after the template is instantiated.
949 if (isa<CXXDestructorDecl>(New) && New->getParent()->isDependentType())
952 // If the old exception specification hasn't been parsed yet, or the new
953 // exception specification can't be computed yet, remember that we need to
954 // perform this check when we get to the end of the outermost
955 // lexically-surrounding class.
956 if (exceptionSpecNotKnownYet(Old) || exceptionSpecNotKnownYet(New)) {
957 DelayedOverridingExceptionSpecChecks.push_back({New, Old});
961 unsigned DiagID = diag::err_override_exception_spec;
962 if (getLangOpts().MicrosoftExt)
963 DiagID = diag::ext_override_exception_spec;
964 return CheckExceptionSpecSubset(PDiag(DiagID),
965 PDiag(diag::err_deep_exception_specs_differ),
966 PDiag(diag::note_overridden_virtual_function),
967 PDiag(diag::ext_override_exception_spec),
968 Old->getType()->getAs<FunctionProtoType>(),
970 New->getType()->getAs<FunctionProtoType>(),
974 static CanThrowResult canSubExprsThrow(Sema &S, const Expr *E) {
975 CanThrowResult R = CT_Cannot;
976 for (const Stmt *SubStmt : E->children()) {
977 R = mergeCanThrow(R, S.canThrow(cast<Expr>(SubStmt)));
984 static CanThrowResult canCalleeThrow(Sema &S, const Expr *E, const Decl *D) {
985 // As an extension, we assume that __attribute__((nothrow)) functions don't
987 if (D && isa<FunctionDecl>(D) && D->hasAttr<NoThrowAttr>())
992 // In C++1z, just look at the function type of the callee.
993 if (S.getLangOpts().CPlusPlus17 && isa<CallExpr>(E)) {
994 E = cast<CallExpr>(E)->getCallee();
996 if (T->isSpecificPlaceholderType(BuiltinType::BoundMember)) {
997 // Sadly we don't preserve the actual type as part of the "bound member"
998 // placeholder, so we need to reconstruct it.
999 E = E->IgnoreParenImpCasts();
1001 // Could be a call to a pointer-to-member or a plain member access.
1002 if (auto *Op = dyn_cast<BinaryOperator>(E)) {
1003 assert(Op->getOpcode() == BO_PtrMemD || Op->getOpcode() == BO_PtrMemI);
1004 T = Op->getRHS()->getType()
1005 ->castAs<MemberPointerType>()->getPointeeType();
1007 T = cast<MemberExpr>(E)->getMemberDecl()->getType();
1010 } else if (const ValueDecl *VD = dyn_cast_or_null<ValueDecl>(D))
1013 // If we have no clue what we're calling, assume the worst.
1016 const FunctionProtoType *FT;
1017 if ((FT = T->getAs<FunctionProtoType>())) {
1018 } else if (const PointerType *PT = T->getAs<PointerType>())
1019 FT = PT->getPointeeType()->getAs<FunctionProtoType>();
1020 else if (const ReferenceType *RT = T->getAs<ReferenceType>())
1021 FT = RT->getPointeeType()->getAs<FunctionProtoType>();
1022 else if (const MemberPointerType *MT = T->getAs<MemberPointerType>())
1023 FT = MT->getPointeeType()->getAs<FunctionProtoType>();
1024 else if (const BlockPointerType *BT = T->getAs<BlockPointerType>())
1025 FT = BT->getPointeeType()->getAs<FunctionProtoType>();
1030 FT = S.ResolveExceptionSpec(E->getBeginLoc(), FT);
1034 return FT->canThrow();
1037 static CanThrowResult canDynamicCastThrow(const CXXDynamicCastExpr *DC) {
1038 if (DC->isTypeDependent())
1039 return CT_Dependent;
1041 if (!DC->getTypeAsWritten()->isReferenceType())
1044 if (DC->getSubExpr()->isTypeDependent())
1045 return CT_Dependent;
1047 return DC->getCastKind() == clang::CK_Dynamic? CT_Can : CT_Cannot;
1050 static CanThrowResult canTypeidThrow(Sema &S, const CXXTypeidExpr *DC) {
1051 if (DC->isTypeOperand())
1054 Expr *Op = DC->getExprOperand();
1055 if (Op->isTypeDependent())
1056 return CT_Dependent;
1058 const RecordType *RT = Op->getType()->getAs<RecordType>();
1062 if (!cast<CXXRecordDecl>(RT->getDecl())->isPolymorphic())
1065 if (Op->Classify(S.Context).isPRValue())
1071 CanThrowResult Sema::canThrow(const Expr *E) {
1072 // C++ [expr.unary.noexcept]p3:
1073 // [Can throw] if in a potentially-evaluated context the expression would
1075 switch (E->getStmtClass()) {
1076 case Expr::ConstantExprClass:
1077 return canThrow(cast<ConstantExpr>(E)->getSubExpr());
1079 case Expr::CXXThrowExprClass:
1080 // - a potentially evaluated throw-expression
1083 case Expr::CXXDynamicCastExprClass: {
1084 // - a potentially evaluated dynamic_cast expression dynamic_cast<T>(v),
1085 // where T is a reference type, that requires a run-time check
1086 CanThrowResult CT = canDynamicCastThrow(cast<CXXDynamicCastExpr>(E));
1089 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1092 case Expr::CXXTypeidExprClass:
1093 // - a potentially evaluated typeid expression applied to a glvalue
1094 // expression whose type is a polymorphic class type
1095 return canTypeidThrow(*this, cast<CXXTypeidExpr>(E));
1097 // - a potentially evaluated call to a function, member function, function
1098 // pointer, or member function pointer that does not have a non-throwing
1099 // exception-specification
1100 case Expr::CallExprClass:
1101 case Expr::CXXMemberCallExprClass:
1102 case Expr::CXXOperatorCallExprClass:
1103 case Expr::UserDefinedLiteralClass: {
1104 const CallExpr *CE = cast<CallExpr>(E);
1106 if (E->isTypeDependent())
1108 else if (isa<CXXPseudoDestructorExpr>(CE->getCallee()->IgnoreParens()))
1111 CT = canCalleeThrow(*this, E, CE->getCalleeDecl());
1114 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1117 case Expr::CXXConstructExprClass:
1118 case Expr::CXXTemporaryObjectExprClass: {
1119 CanThrowResult CT = canCalleeThrow(*this, E,
1120 cast<CXXConstructExpr>(E)->getConstructor());
1123 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1126 case Expr::CXXInheritedCtorInitExprClass:
1127 return canCalleeThrow(*this, E,
1128 cast<CXXInheritedCtorInitExpr>(E)->getConstructor());
1130 case Expr::LambdaExprClass: {
1131 const LambdaExpr *Lambda = cast<LambdaExpr>(E);
1132 CanThrowResult CT = CT_Cannot;
1133 for (LambdaExpr::const_capture_init_iterator
1134 Cap = Lambda->capture_init_begin(),
1135 CapEnd = Lambda->capture_init_end();
1136 Cap != CapEnd; ++Cap)
1137 CT = mergeCanThrow(CT, canThrow(*Cap));
1141 case Expr::CXXNewExprClass: {
1143 if (E->isTypeDependent())
1146 CT = canCalleeThrow(*this, E, cast<CXXNewExpr>(E)->getOperatorNew());
1149 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1152 case Expr::CXXDeleteExprClass: {
1154 QualType DTy = cast<CXXDeleteExpr>(E)->getDestroyedType();
1155 if (DTy.isNull() || DTy->isDependentType()) {
1158 CT = canCalleeThrow(*this, E,
1159 cast<CXXDeleteExpr>(E)->getOperatorDelete());
1160 if (const RecordType *RT = DTy->getAs<RecordType>()) {
1161 const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
1162 const CXXDestructorDecl *DD = RD->getDestructor();
1164 CT = mergeCanThrow(CT, canCalleeThrow(*this, E, DD));
1169 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1172 case Expr::CXXBindTemporaryExprClass: {
1173 // The bound temporary has to be destroyed again, which might throw.
1174 CanThrowResult CT = canCalleeThrow(*this, E,
1175 cast<CXXBindTemporaryExpr>(E)->getTemporary()->getDestructor());
1178 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1181 // ObjC message sends are like function calls, but never have exception
1183 case Expr::ObjCMessageExprClass:
1184 case Expr::ObjCPropertyRefExprClass:
1185 case Expr::ObjCSubscriptRefExprClass:
1188 // All the ObjC literals that are implemented as calls are
1189 // potentially throwing unless we decide to close off that
1191 case Expr::ObjCArrayLiteralClass:
1192 case Expr::ObjCDictionaryLiteralClass:
1193 case Expr::ObjCBoxedExprClass:
1196 // Many other things have subexpressions, so we have to test those.
1198 case Expr::CoawaitExprClass:
1199 case Expr::ConditionalOperatorClass:
1200 case Expr::CompoundLiteralExprClass:
1201 case Expr::CoyieldExprClass:
1202 case Expr::CXXConstCastExprClass:
1203 case Expr::CXXReinterpretCastExprClass:
1204 case Expr::BuiltinBitCastExprClass:
1205 case Expr::CXXStdInitializerListExprClass:
1206 case Expr::DesignatedInitExprClass:
1207 case Expr::DesignatedInitUpdateExprClass:
1208 case Expr::ExprWithCleanupsClass:
1209 case Expr::ExtVectorElementExprClass:
1210 case Expr::InitListExprClass:
1211 case Expr::ArrayInitLoopExprClass:
1212 case Expr::MemberExprClass:
1213 case Expr::ObjCIsaExprClass:
1214 case Expr::ObjCIvarRefExprClass:
1215 case Expr::ParenExprClass:
1216 case Expr::ParenListExprClass:
1217 case Expr::ShuffleVectorExprClass:
1218 case Expr::ConvertVectorExprClass:
1219 case Expr::VAArgExprClass:
1220 return canSubExprsThrow(*this, E);
1222 // Some might be dependent for other reasons.
1223 case Expr::ArraySubscriptExprClass:
1224 case Expr::OMPArraySectionExprClass:
1225 case Expr::BinaryOperatorClass:
1226 case Expr::DependentCoawaitExprClass:
1227 case Expr::CompoundAssignOperatorClass:
1228 case Expr::CStyleCastExprClass:
1229 case Expr::CXXStaticCastExprClass:
1230 case Expr::CXXFunctionalCastExprClass:
1231 case Expr::ImplicitCastExprClass:
1232 case Expr::MaterializeTemporaryExprClass:
1233 case Expr::UnaryOperatorClass: {
1234 CanThrowResult CT = E->isTypeDependent() ? CT_Dependent : CT_Cannot;
1235 return mergeCanThrow(CT, canSubExprsThrow(*this, E));
1238 // FIXME: We should handle StmtExpr, but that opens a MASSIVE can of worms.
1239 case Expr::StmtExprClass:
1242 case Expr::CXXDefaultArgExprClass:
1243 return canThrow(cast<CXXDefaultArgExpr>(E)->getExpr());
1245 case Expr::CXXDefaultInitExprClass:
1246 return canThrow(cast<CXXDefaultInitExpr>(E)->getExpr());
1248 case Expr::ChooseExprClass:
1249 if (E->isTypeDependent() || E->isValueDependent())
1250 return CT_Dependent;
1251 return canThrow(cast<ChooseExpr>(E)->getChosenSubExpr());
1253 case Expr::GenericSelectionExprClass:
1254 if (cast<GenericSelectionExpr>(E)->isResultDependent())
1255 return CT_Dependent;
1256 return canThrow(cast<GenericSelectionExpr>(E)->getResultExpr());
1258 // Some expressions are always dependent.
1259 case Expr::CXXDependentScopeMemberExprClass:
1260 case Expr::CXXUnresolvedConstructExprClass:
1261 case Expr::DependentScopeDeclRefExprClass:
1262 case Expr::CXXFoldExprClass:
1263 return CT_Dependent;
1265 case Expr::AsTypeExprClass:
1266 case Expr::BinaryConditionalOperatorClass:
1267 case Expr::BlockExprClass:
1268 case Expr::CUDAKernelCallExprClass:
1269 case Expr::DeclRefExprClass:
1270 case Expr::ObjCBridgedCastExprClass:
1271 case Expr::ObjCIndirectCopyRestoreExprClass:
1272 case Expr::ObjCProtocolExprClass:
1273 case Expr::ObjCSelectorExprClass:
1274 case Expr::ObjCAvailabilityCheckExprClass:
1275 case Expr::OffsetOfExprClass:
1276 case Expr::PackExpansionExprClass:
1277 case Expr::PseudoObjectExprClass:
1278 case Expr::SubstNonTypeTemplateParmExprClass:
1279 case Expr::SubstNonTypeTemplateParmPackExprClass:
1280 case Expr::FunctionParmPackExprClass:
1281 case Expr::UnaryExprOrTypeTraitExprClass:
1282 case Expr::UnresolvedLookupExprClass:
1283 case Expr::UnresolvedMemberExprClass:
1284 case Expr::TypoExprClass:
1285 // FIXME: Can any of the above throw? If so, when?
1288 case Expr::AddrLabelExprClass:
1289 case Expr::ArrayTypeTraitExprClass:
1290 case Expr::AtomicExprClass:
1291 case Expr::TypeTraitExprClass:
1292 case Expr::CXXBoolLiteralExprClass:
1293 case Expr::CXXNoexceptExprClass:
1294 case Expr::CXXNullPtrLiteralExprClass:
1295 case Expr::CXXPseudoDestructorExprClass:
1296 case Expr::CXXScalarValueInitExprClass:
1297 case Expr::CXXThisExprClass:
1298 case Expr::CXXUuidofExprClass:
1299 case Expr::CharacterLiteralClass:
1300 case Expr::ExpressionTraitExprClass:
1301 case Expr::FloatingLiteralClass:
1302 case Expr::GNUNullExprClass:
1303 case Expr::ImaginaryLiteralClass:
1304 case Expr::ImplicitValueInitExprClass:
1305 case Expr::IntegerLiteralClass:
1306 case Expr::FixedPointLiteralClass:
1307 case Expr::ArrayInitIndexExprClass:
1308 case Expr::NoInitExprClass:
1309 case Expr::ObjCEncodeExprClass:
1310 case Expr::ObjCStringLiteralClass:
1311 case Expr::ObjCBoolLiteralExprClass:
1312 case Expr::OpaqueValueExprClass:
1313 case Expr::PredefinedExprClass:
1314 case Expr::SizeOfPackExprClass:
1315 case Expr::StringLiteralClass:
1316 case Expr::SourceLocExprClass:
1317 // These expressions can never throw.
1320 case Expr::MSPropertyRefExprClass:
1321 case Expr::MSPropertySubscriptExprClass:
1322 llvm_unreachable("Invalid class for expression");
1324 #define STMT(CLASS, PARENT) case Expr::CLASS##Class:
1325 #define STMT_RANGE(Base, First, Last)
1326 #define LAST_STMT_RANGE(BASE, FIRST, LAST)
1327 #define EXPR(CLASS, PARENT)
1328 #define ABSTRACT_STMT(STMT)
1329 #include "clang/AST/StmtNodes.inc"
1330 case Expr::NoStmtClass:
1331 llvm_unreachable("Invalid class for expression");
1333 llvm_unreachable("Bogus StmtClass");
1336 } // end namespace clang