Re: [PATCH v2] scripts/check-local-export: avoid 'wait $!' for process substitution

From: Masahiro Yamada
Date: Tue Jun 07 2022 - 23:39:49 EST


On Wed, Jun 8, 2022 at 2:24 AM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote:
>
> On Tue, Jun 7, 2022 at 9:41 AM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
> >
> > Bash>=4.4 supports 'wait $!' to check the exit status of a process
> > substitution, but some people using older bash versions reported an
> > error like this:
> >
> > Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> > Reported-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> > Reported-by: Wang Yugui <wangyugui@xxxxxxxxxxxx>
> > Tested-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> > Tested-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> > Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
>
> Acked-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
>
> Some comments below.
>
> > diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
> > index 34415ae1af1b..19c286c23786 100644
> > --- a/Documentation/process/changes.rst
> > +++ b/Documentation/process/changes.rst
> > @@ -32,6 +32,7 @@ you probably needn't concern yourself with pcmciautils.
> > GNU C 5.1 gcc --version
> > Clang/LLVM (optional) 11.0.0 clang --version
> > GNU make 3.81 make --version
> > +bash 4.2 bash --version
>
> /usr/bin/env bash
> and definitely /bin/bash
> both show up a lot in kernel sources. At this point, I think bash is a
> requirement at this point, so it's good to document it finally.
>
> > +# If there is no symbol in the object, ${NM} (both GNU nm and llvm-nm) shows
> > +# 'no symbols' diagnostic (but exits with 0). It is harmless and hidden by
> > +# '2>/dev/null'. However, it suppresses real error messages as well. Add a
> > +# hand-crafted error message here.
> > +#
> > +# Use --quiet instead of 2>/dev/null when we upgrade the minimum version of
> > +# binutils to 2.37, llvm to 13.0.0.
>
> Might be nice to include `TODO:` in the comment block. Vim will
> highlight these in comments.


OK. will do.

Thanks.


--
Best Regards
Masahiro Yamada