From: Yonghong Song <yonghong.song@linux.dev>
To: David Faust <david.faust@oracle.com>,
"Jose E. Marchesi" <jose.marchesi@oracle.com>,
bpf@vger.kernel.org
Cc: cupertino.miranda@oracle.com, Eduard Zingerman <eddyz87@gmail.com>
Subject: Re: [PATCH bpf-next] bpf: disable some `attribute ignored' warnings in GCC
Date: Mon, 6 May 2024 14:42:43 -0700 [thread overview]
Message-ID: <74b4dfa9-f0c0-4b9c-9353-d82b2d74c1ba@linux.dev> (raw)
In-Reply-To: <18123833-2d51-432d-9803-20dd76d7cccd@oracle.com>
On 5/6/24 12:09 PM, David Faust wrote:
>
> On 5/6/24 11:32 AM, Yonghong Song wrote:
>> On 5/3/24 5:32 AM, Jose E. Marchesi wrote:
>>> This patch modifies selftests/bpf/Makefile to pass -Wno-attributes to
>>> GCC. This is because of the following attributes which are ignored:
>>>
>>> - btf_decl_tag
>>> - btf_type_tag
>>>
>>> There are many of these. At the moment none of these are
>>> recognized/handled by gcc-bpf.
>>>
>>> We are aware that btf_decl_tag is necessary for some of the
>>> selftest harness to communicate test failure/success. Support for
>>> it is in progress in GCC upstream:
>>>
>>> https://gcc.gnu.org/pipermail/gcc-patches/2024-May/650482.html
>>>
>>> However, the GCC master branch is not yet open, so the series
>>> above (currently under review upstream) wont be able to make it
>>> there until 14.1 gets released, probably mid next week.
>> Thanks. It would be great if the patch can be merged soon.
> A small note here - the above series does not itself contain the patch
> to support decl_tag, it is just some prerequisite structural changes and
> the option to prune BTF before emission similar to clang to slim the
> selftest (and other) program sizes down.
>
> The patch to enable decl_tag for functions in BTF, enough for the
> selftest harness, can go up after that. But, it will require some
> approvals from the C front-end maintainers, since it is a new attribute,
> so it may take longer, and may be contentious.
Thanks for the update! Let me know if I can help from llvm/kernel/bpf
perspective.
>
>>> As for btf_type_tag, more extensive work will be needed in GCC
>>> upstream to support it in both BTF and DWARF. We have a WIP big
>>> patch for that, but that is not needed to compile/build the
>>> selftests.
>> Thanks. Eduard has implemented in llvm with agreed new format. Since
>> the old phabricator becomes readonly, he will upstream the original
>> patch to llvm-project soon.
[...]
prev parent reply other threads:[~2024-05-06 21:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-03 12:32 [PATCH bpf-next] bpf: disable some `attribute ignored' warnings in GCC Jose E. Marchesi
2024-05-06 18:32 ` Yonghong Song
2024-05-06 19:09 ` David Faust
2024-05-06 21:42 ` Yonghong Song [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=74b4dfa9-f0c0-4b9c-9353-d82b2d74c1ba@linux.dev \
--to=yonghong.song@linux.dev \
--cc=bpf@vger.kernel.org \
--cc=cupertino.miranda@oracle.com \
--cc=david.faust@oracle.com \
--cc=eddyz87@gmail.com \
--cc=jose.marchesi@oracle.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).