Add support for attribute 'trivial_abi'.
The 'trivial_abi' attribute can be applied to a C++ class, struct, or
union. It makes special functions of the annotated class (the destructor
and copy/move constructors) to be trivial for the purpose of calls and,
as a result, enables the annotated class or containing classes to be
passed or returned using the C ABI for the underlying type.
When a type that is considered trivial for the purpose of calls despite
having a non-trivial destructor (which happens only when the class type
or one of its subobjects is a 'trivial_abi' class) is passed to a
function, the callee is responsible for destroying the object.
For more background, see the discussions that took place on the mailing
list:
http://lists.llvm.org/pipermail/cfe-dev/2017-November/055955.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180101/thread.html#214043
rdar://problem/35204524
Differential Revision: https://reviews.llvm.org/D41039
llvm-svn: 324269
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 3a6988c..31c1b89 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -10814,23 +10814,18 @@
// information is added for it.
diagnoseArrayStarInParamType(*this, PType, Param->getLocation());
- // MSVC destroys objects passed by value in the callee. Therefore a
- // function definition which takes such a parameter must be able to call the
- // object's destructor. However, we don't perform any direct access check
- // on the dtor.
- if (getLangOpts().CPlusPlus && Context.getTargetInfo()
- .getCXXABI()
- .areArgsDestroyedLeftToRightInCallee()) {
- if (!Param->isInvalidDecl()) {
- if (const RecordType *RT = Param->getType()->getAs<RecordType>()) {
- CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RT->getDecl());
- if (!ClassDecl->isInvalidDecl() &&
- !ClassDecl->hasIrrelevantDestructor() &&
- !ClassDecl->isDependentContext()) {
- CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
- MarkFunctionReferenced(Param->getLocation(), Destructor);
- DiagnoseUseOfDecl(Destructor, Param->getLocation());
- }
+ // If the parameter is a c++ class type and it has to be destructed in the
+ // callee function, declare the destructor so that it can be called by the
+ // callee function. Do not perfom any direct access check on the dtor here.
+ if (!Param->isInvalidDecl()) {
+ if (CXXRecordDecl *ClassDecl = Param->getType()->getAsCXXRecordDecl()) {
+ if (!ClassDecl->isInvalidDecl() &&
+ !ClassDecl->hasIrrelevantDestructor() &&
+ !ClassDecl->isDependentContext() &&
+ Context.isParamDestroyedInCallee(Param->getType())) {
+ CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
+ MarkFunctionReferenced(Param->getLocation(), Destructor);
+ DiagnoseUseOfDecl(Destructor, Param->getLocation());
}
}
}