This reverts commit
b875343873a584965daf507d73ff1fe71eab1953.
Per discussion in https://reviews.llvm.org/D111199, instead to make
existing btf_tag attribute as a type-or-decl attribute, we will
make existing btf_tag attribute as a decl only attribute, and
introduce btf_type_tag as a type only attribute. This will make
it easy for cases like typedef where an attribute may be applied
as either a type attribute or a decl attribute.
let LangOpts = [COnly];
}
-def BTFTag : DeclOrTypeAttr {
+def BTFTag : InheritableAttr {
let Spellings = [Clang<"btf_tag">];
let Args = [StringArgument<"BTFTag">];
let Subjects = SubjectList<[Var, Function, Record, Field], ErrorDiag>;
function, function parameter or variable declaration. If -g is specified,
the ``ARGUMENT`` info will be preserved in IR and be emitted to dwarf.
For BPF targets, the ``ARGUMENT`` info will be emitted to .BTF ELF section too.
-
-The attribute can also be used as a type qualifier. Right now it is accepted
-and silently ignored in order to permit the linux kernel to build with the
-attribute.
}];
}
case attr::UPtr:
case attr::AddressSpace:
case attr::CmseNSCall:
- case attr::BTFTag:
llvm_unreachable("This attribute should have been handled already");
case attr::NSReturnsRetained:
case ParsedAttr::IgnoredAttribute:
break;
- case ParsedAttr::AT_BTFTag:
- // FIXME: Linux kernel may also use this attribute for type casting check,
- // which clang doesn's support for now. Let us ignore them so linux kernel
- // build won't break.
- attr.setUsedAsTypeAttr();
- break;
case ParsedAttr::AT_MayAlias:
// FIXME: This attribute needs to actually be handled, but if we ignore
// it it breaks large amounts of Linux software.
int __tag1 foo(struct t1 *arg __tag1, struct t2 *arg2) {
return arg->a + arg2->a;
}
-
-void * convert(long arg) {
- /* FIXME: the attribute __tag1 is accepted but didn't really do type conversion
- * or enforce type checking. This is to permit linux kernel build with btf_tag
- * attribute.
- */
- return (void __tag1 *)arg;
-}