/// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
/// C++ if/switch/while/for statement.
/// e.g: "if (int x = f()) {...}"
Action::OwningExprResult
Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
Declarator &D,
SourceLocation EqualLoc,
ExprArg AssignExprVal) {
assert(AssignExprVal.get() && "Null assignment expression");
// C++ 6.4p2:
// The declarator shall not specify a function or an array.
// The type-specifier-seq shall not contain typedef and shall not declare a
// new class or enumeration.
assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
"Parser allowed 'typedef' as storage class of condition decl.");
QualType Ty = GetTypeForDeclarator(D, S);
if (Ty->isFunctionType()) { // The declarator shall not specify a function...
// We exit without creating a CXXConditionDeclExpr because a FunctionDecl
// would be created and CXXConditionDeclExpr wants a VarDecl.
return ExprError(Diag(StartLoc, diag::err_invalid_use_of_function_type)
<< SourceRange(StartLoc, EqualLoc));
} else if (Ty->isArrayType()) { // ...or an array.
Diag(StartLoc, diag::err_invalid_use_of_array_type)
<< SourceRange(StartLoc, EqualLoc);
} else if (const RecordType *RT = Ty->getAsRecordType()) {
RecordDecl *RD = RT->getDecl();
// The type-specifier-seq shall not declare a new class...
if (RD->isDefinition() &&
(RD->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(RD))))
Diag(RD->getLocation(), diag::err_type_defined_in_condition);
} else if (const EnumType *ET = Ty->getAsEnumType()) {
EnumDecl *ED = ET->getDecl();
// ...or enumeration.
if (ED->isDefinition() &&
(ED->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(ED))))
Diag(ED->getLocation(), diag::err_type_defined_in_condition);
}
DeclPtrTy Dcl = ActOnDeclarator(S, D, DeclPtrTy());
if (!Dcl)
return ExprError();
AddInitializerToDecl(Dcl, move(AssignExprVal));
// Mark this variable as one that is declared within a conditional.
// We know that the decl had to be a VarDecl because that is the only type of
// decl that can be assigned and the grammar requires an '='.
VarDecl *VD = cast<VarDecl>(Dcl.getAs<Decl>());
VD->setDeclaredInCondition(true);
return Owned(new (Context) CXXConditionDeclExpr(StartLoc, EqualLoc, VD));
}
