Re: [PATCH] scripts/setlocalversion: clear local varaible to make it work for sh

From: Geert Uytterhoeven
Date: Tue Oct 01 2019 - 09:20:41 EST


Hi Yamada-san,

s/varaible/variable/ in subject.

On Tue, Oct 1, 2019 at 2:17 PM Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> wrote:
> Geert Uytterhoeven reports a strange side-effect of commit 858805b336be
> ("kbuild: add $(BASH) to run scripts with bash-extension"), which
> inserts the contents of a localversion file in the build directory twice.
>
> [Steps to Reproduce]
> $ echo bar > localversion
> $ mkdir build
> $ cd build/
> $ echo foo > localversion
> $ make -s -f ../Makefile defconfig include/config/kernel.release
> $ cat include/config/kernel.release
> 5.4.0-rc1foofoobar
>
> This comes down to the behavior change of 'local' variables.
>
> The 'man sh' on my Ubuntu machine, where sh is an alias to dash,
> explains as follows:
> When a variable is made local, it inherits the initial value and
> exported and readonly flags from the variable with the same name
> in the surrounding scope, if there is one. Otherwise, the variable
> is initially unset.
>
> [Test Code]
>
> foo ()
> {
> local res
> echo "res: $res"
> }
>
> res=1
> foo
>
> [Result]
>
> $ sh test.sh
> res: 1
> $ bash test.sh
> res:
>
> So, scripts/setlocalversion correctly works only for bash in spite of
> its hashbang being #!/bin/sh. Nobody had noticed it before because
> CONFIG_SHELL was previously set to sh only when bash is missing, which
> is very unlikely to happen.
>
> The benefit of commit 858805b336be is to make people write portable and
> correct code. I gave it the Fixes tag since it uncovered the issue for
> most of people.
>
> Clear the variable 'res' in collect_files() to make it work for sh
> (and it also works on distributions where sh is an alias to bash).
>
> Fixes: commit 858805b336be ("kbuild: add $(BASH) to run scripts with bash-extension")
> Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>

Can you please use

Reported-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

instead?

> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>

Thanks, that fixes the issue for me!

Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds