On Tue, Sep 14, 2021 at 11:10 PM Yonghong Song <yhs@xxxxxx> wrote:
>
> Commit c240ba287890 ("selftests/bpf: Add a test with a bpf
> program with btf_tag attributes") added btf_tag selftest
> to test BTF_KIND_TAG generation from C source code, and to
> test kernel validation of generated BTF types.
> But if an old clang (clang 13 or earlier) is used, the
> following compiler warning may be seen:
> progs/tag.c:23:20: warning: unknown attribute 'btf_tag' ignored
> and the test itself is marked OK. The compiler warning is bad
> and the test itself shouldn't be marked OK.
>
> This patch added the check for btf_tag attribute support.
> If btf_tag is not supported by the clang, the attribute will
> not be used in the code and the test will be marked as skipped.
> For example, with clang 13:
> ./test_progs -t btf_tag
> #21 btf_tag:SKIP
> Summary: 1/0 PASSED, 1 SKIPPED, 0 FAILED
>
> The selftests/README.rst is updated to clarify when the btf_tag
> test may be skipped.
>
> Signed-off-by: Yonghong Song <yhs@xxxxxx>
Applied. Thanks for the quick follow up.
