Re: [PATCH 2/2] pahole: Allow asking for extra features using the '+' prefix in --btf_features

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Fri, Apr 19, 2024 at 1:58 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> From: Arnaldo Carvalho de Melo <acme@redhat.com>
>
> Instead of the somewhat confusing:
>
>   --btf_features=all,reproducible_build
>
> That means "'all' the standard BTF features plus the 'reproducible_build'
> extra BTF feature", use + directly, making it more compact:
>
>   --btf_features=+reproducible_build
>

for older paholes that don't yet know about + syntax, but support
--btf_features, will this effectively disable all features or how will
it work?

I'm thinking from the perspective of using +reproducible_build
unconditionally in kernel's build scripts, will it regress something
for current pahole versions?

> In the future we may want the '-' counterpart as a way to _remove_ some
> of the standard set of BTF features.
>
> Cc: Alan Maguire <alan.maguire@oracle.com>
> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
> Cc: Daniel Xu <dxu@dxuuu.xyz>
> Cc: Eduard Zingerman <eddyz87@gmail.com>
> Cc: Jiri Olsa <jolsa@kernel.org>
> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> ---
>  man-pages/pahole.1          | 6 ++++++
>  pahole.c                    | 6 ++++++
>  tests/reproducible_build.sh | 2 +-
>  3 files changed, 13 insertions(+), 1 deletion(-)
>

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