Author: Yonghong Song Date: 2021-10-11T15:34:26-07:00 New Revision: c5fb1a09533ec2ed43a80f39c1592e5ee887ef9e
URL: https://github.com/llvm/llvm-project/commit/c5fb1a09533ec2ed43a80f39c1592e5ee887ef9e DIFF: https://github.com/llvm/llvm-project/commit/c5fb1a09533ec2ed43a80f39c1592e5ee887ef9e.diff LOG: Revert "[Clang] Ignore BTFTag attr if used as a type attribute" 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. Added: Modified: clang/include/clang/Basic/Attr.td clang/include/clang/Basic/AttrDocs.td clang/lib/AST/TypePrinter.cpp clang/lib/Sema/SemaType.cpp clang/test/Sema/attr-btf_tag.c Removed: ################################################################################ diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td index bd6510677fac0..c39657e6c8351 100644 --- a/clang/include/clang/Basic/Attr.td +++ b/clang/include/clang/Basic/Attr.td @@ -1836,7 +1836,7 @@ def BPFPreserveAccessIndex : InheritableAttr, 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>; diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td index d3b0de06e7172..b2b41c3bb4197 100644 --- a/clang/include/clang/Basic/AttrDocs.td +++ b/clang/include/clang/Basic/AttrDocs.td @@ -2019,10 +2019,6 @@ targets. This attribute may be attached to a struct/union, struct/union field, 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. }]; } diff --git a/clang/lib/AST/TypePrinter.cpp b/clang/lib/AST/TypePrinter.cpp index 2805916b1f7bb..3c7a6b8b9e953 100644 --- a/clang/lib/AST/TypePrinter.cpp +++ b/clang/lib/AST/TypePrinter.cpp @@ -1704,7 +1704,6 @@ void TypePrinter::printAttributedAfter(const AttributedType *T, case attr::UPtr: case attr::AddressSpace: case attr::CmseNSCall: - case attr::BTFTag: llvm_unreachable("This attribute should have been handled already"); case attr::NSReturnsRetained: diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp index 11a6d3faf2dd6..d2d54281c63e0 100644 --- a/clang/lib/Sema/SemaType.cpp +++ b/clang/lib/Sema/SemaType.cpp @@ -8127,12 +8127,6 @@ static void processTypeAttrs(TypeProcessingState &state, QualType &type, 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. diff --git a/clang/test/Sema/attr-btf_tag.c b/clang/test/Sema/attr-btf_tag.c index 2ba2515868344..88452fa875b1a 100644 --- a/clang/test/Sema/attr-btf_tag.c +++ b/clang/test/Sema/attr-btf_tag.c @@ -40,11 +40,3 @@ int __tag2 __tag3 foo(struct t1 *arg, struct t2 *arg2); 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; -} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
