"defaulting this %select{default constructor|copy constructor|move "
"constructor|copy assignment operator|move assignment operator|destructor}0 "
"would delete it after its first declaration">;
+def ext_implicit_exception_spec_mismatch : ExtWarn<
+ "function previously declared with an %select{explicit|implicit}0 exception "
+ "specification redeclared with an %select{implicit|explicit}0 exception "
+ "specification">, InGroup<DiagGroup<"implicit-exception-spec-mismatch">>;
def warn_ptr_arith_precedes_bounds : Warning<
"the pointer decremented by %0 refers before the beginning of the array">,
diag::err_static_out_of_line)
<< FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
}
+
+ // C++11 [except.spec]p15:
+ // A deallocation function with no exception-specification is treated
+ // as if it were specified with noexcept(true).
+ const FunctionProtoType *FPT = R->getAs<FunctionProtoType>();
+ if ((Name.getCXXOverloadedOperator() == OO_Delete ||
+ Name.getCXXOverloadedOperator() == OO_Array_Delete) &&
+ getLangOpts().CPlusPlus0x && FPT && !FPT->hasExceptionSpec()) {
+ FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
+ EPI.ExceptionSpecType = EST_BasicNoexcept;
+ NewFD->setType(Context.getFunctionType(FPT->getResultType(),
+ FPT->arg_type_begin(),
+ FPT->getNumArgs(), EPI));
+ }
}
// Filter out previous declarations that don't match the scope.
}
static bool
-CheckOperatorDeleteDeclaration(Sema &SemaRef, const FunctionDecl *FnDecl) {
+CheckOperatorDeleteDeclaration(Sema &SemaRef, FunctionDecl *FnDecl) {
// C++ [basic.stc.dynamic.deallocation]p1:
// A program is ill-formed if deallocation functions are declared in a
// namespace scope other than global scope or declared static in global
return SourceDecl->getType()->castAs<FunctionProtoType>();
}
-/// Get the type that a function had prior to adjustment of the exception
+/// Determine whether a function has an implicitly-generated exception
/// specification.
-static const FunctionProtoType *getUnadjustedFunctionType(FunctionDecl *Decl) {
- if (isa<CXXDestructorDecl>(Decl) && Decl->getTypeSourceInfo()) {
- const FunctionProtoType *Ty =
- Decl->getTypeSourceInfo()->getType()->getAs<FunctionProtoType>();
- if (!Ty->hasExceptionSpec())
- // The type will be adjusted. Use the EST_None exception specification
- // from the type as written.
- return Ty;
- }
+static bool hasImplicitExceptionSpec(FunctionDecl *Decl) {
+ if (!isa<CXXDestructorDecl>(Decl) &&
+ Decl->getDeclName().getCXXOverloadedOperator() != OO_Delete &&
+ Decl->getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
+ return false;
+
+ // If the user didn't declare the function, its exception specification must
+ // be implicit.
+ if (!Decl->getTypeSourceInfo())
+ return true;
- // Use whatever type the function now has. The TypeSourceInfo does not contain
- // an instantiated exception specification for a function template,
- return Decl->getType()->getAs<FunctionProtoType>();
+ const FunctionProtoType *Ty =
+ Decl->getTypeSourceInfo()->getType()->getAs<FunctionProtoType>();
+ return !Ty->hasExceptionSpec();
}
bool Sema::CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New) {
// specification adjustment is applied.
if (!CheckEquivalentExceptionSpec(
PDiag(DiagID), PDiag(diag::note_previous_declaration),
- getUnadjustedFunctionType(Old), Old->getLocation(),
- getUnadjustedFunctionType(New), New->getLocation(),
+ Old->getType()->getAs<FunctionProtoType>(), Old->getLocation(),
+ New->getType()->getAs<FunctionProtoType>(), New->getLocation(),
&MissingExceptionSpecification, &MissingEmptyExceptionSpecification,
- /*AllowNoexceptAllMatchWithNoSpec=*/true, IsOperatorNew))
+ /*AllowNoexceptAllMatchWithNoSpec=*/true, IsOperatorNew)) {
+ // C++11 [except.spec]p4 [DR1492]:
+ // If a declaration of a function has an implicit
+ // exception-specification, other declarations of the function shall
+ // not specify an exception-specification.
+ if (getLangOpts().CPlusPlus0x &&
+ hasImplicitExceptionSpec(Old) != hasImplicitExceptionSpec(New)) {
+ Diag(New->getLocation(), diag::ext_implicit_exception_spec_mismatch)
+ << hasImplicitExceptionSpec(Old);
+ if (!Old->getLocation().isInvalid())
+ Diag(Old->getLocation(), diag::note_previous_declaration);
+ }
return false;
+ }
// The failure was something other than an empty exception
// specification; return an error.
if (!MissingExceptionSpecification && !MissingEmptyExceptionSpecification)
return true;
- const FunctionProtoType *NewProto = getUnadjustedFunctionType(New);
+ const FunctionProtoType *NewProto =
+ New->getType()->getAs<FunctionProtoType>();
// The new function declaration is only missing an empty exception
// specification "throw()". If the throw() specification came from a
}
if (MissingExceptionSpecification && NewProto) {
- const FunctionProtoType *OldProto = getUnadjustedFunctionType(Old);
+ const FunctionProtoType *OldProto =
+ Old->getType()->getAs<FunctionProtoType>();
FunctionProtoType::ExtProtoInfo EPI = NewProto->getExtProtoInfo();
EPI.ExceptionSpecType = OldProto->getExceptionSpecType();
/// CheckEquivalentExceptionSpec - Check if the two types have compatible
/// exception specifications. See C++ [except.spec]p3.
+///
+/// \return \c false if the exception specifications match, \c true if there is
+/// a problem. If \c true is returned, either a diagnostic has already been
+/// produced or \c *MissingExceptionSpecification is set to \c true.
bool Sema::CheckEquivalentExceptionSpec(const PartialDiagnostic &DiagID,
const PartialDiagnostic & NoteID,
const FunctionProtoType *Old,
ASTContext &Context = S.Context;
const LangOptions &LangOpts = S.getLangOpts();
- bool ImplicitlyNoexcept = false;
- if (D.getName().getKind() == UnqualifiedId::IK_OperatorFunctionId &&
- LangOpts.CPlusPlus0x) {
- OverloadedOperatorKind OO = D.getName().OperatorFunctionId.Operator;
- /// In C++0x, deallocation functions (normal and array operator delete)
- /// are implicitly noexcept.
- if (OO == OO_Delete || OO == OO_Array_Delete)
- ImplicitlyNoexcept = true;
- }
-
// The name we're declaring, if any.
DeclarationName Name;
if (D.getIdentifier())
Exceptions,
EPI);
- if (FTI.getExceptionSpecType() == EST_None &&
- ImplicitlyNoexcept && chunkIndex == 0) {
- // Only the outermost chunk is marked noexcept, of course.
- EPI.ExceptionSpecType = EST_BasicNoexcept;
- }
-
T = Context.getFunctionType(T, ArgTys.data(), ArgTys.size(), EPI);
}
delete[] new int[1];
}
-void operator delete(void*) noexcept;
-void operator delete[](void*) noexcept;
+void operator delete(void*);
+void operator delete[](void*);
+
+static_assert(noexcept(operator delete(0)), "");
+static_assert(noexcept(operator delete[](0)), "");
// Same goes for explicit declarations.
void operator delete(void*, float);
-void operator delete(void*, float) noexcept;
-
void operator delete[](void*, float);
-void operator delete[](void*, float) noexcept;
+
+static_assert(noexcept(operator delete(0, 0.f)), "");
+static_assert(noexcept(operator delete[](0, 0.f)), "");
// But explicit specs stay.
void operator delete(void*, double) throw(int); // expected-note {{previous}}
+static_assert(!noexcept(operator delete(0, 0.)), "");
void operator delete(void*, double) noexcept; // expected-error {{does not match}}
--- /dev/null
+// RUN: %clang_cc1 -std=c++11 %s -verify -fcxx-exceptions
+
+// We permit overriding an implicit exception specification with an explicit one
+// as an extension, for compatibility with existing code.
+
+struct S {
+ void a(); // expected-note {{here}}
+ ~S(); // expected-note {{here}}
+ void operator delete(void*); // expected-note {{here}}
+};
+
+void S::a() noexcept {} // expected-error {{does not match previous}}
+S::~S() noexcept {} // expected-warning {{function previously declared with an implicit exception specification redeclared with an explicit exception specification}}
+void S::operator delete(void*) noexcept {} // expected-warning {{function previously declared with an implicit exception specification redeclared with an explicit exception specification}}
+
+struct T {
+ void a() noexcept; // expected-note {{here}}
+ ~T() noexcept; // expected-note {{here}}
+ void operator delete(void*) noexcept; // expected-note {{here}}
+};
+
+void T::a() {} // expected-warning {{missing exception specification 'noexcept'}}
+T::~T() {} // expected-warning {{function previously declared with an explicit exception specification redeclared with an implicit exception specification}}
+void T::operator delete(void*) {} // expected-warning {{function previously declared with an explicit exception specification redeclared with an implicit exception specification}}
+
+
+// The extension does not extend to function templates.
+
+template<typename T> struct U {
+ T t;
+ ~U(); // expected-note {{here}}
+ void operator delete(void*); // expected-note {{here}}
+};
+
+template<typename T> U<T>::~U() noexcept(true) {} // expected-error {{exception specification in declaration does not match previous declaration}}
+template<typename T> void U<T>::operator delete(void*) noexcept(false) {} // expected-error {{exception specification in declaration does not match previous declaration}}
// the exception specification adjustment occurs.
namespace DR1492 {
struct A { ~A(); }; // expected-note {{here}}
- A::~A() noexcept {} // expected-error {{does not match previous declaration}}
+ A::~A() noexcept {} // expected-warning {{previously declared with an implicit exception specification}}
struct B { ~B() noexcept; }; // expected-note {{here}}
- B::~B() {} // expected-warning {{~B' is missing exception specification 'noexcept'}}
+ B::~B() {} // expected-warning {{previously declared with an explicit exception specification}}
template<typename T> struct C {
T t;