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Date:   Tue, 7 Jun 2022 19:11:31 +0900
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Subject: Re: [PATCH v2] kbuild: fix build failure by
 scripts/check-local-export
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To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>
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 <CAK7LNAREqTb=Y08R-jX8mNZoTmEYt_6WrUrP+U2oZQk2tT9kBg@mail.gmail.com>
From:   Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
In-Reply-To: <CAK7LNAREqTb=Y08R-jX8mNZoTmEYt_6WrUrP+U2oZQk2tT9kBg@mail.gmail.com>
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On 2022/06/07 17:34, Masahiro Yamada wrote:
> This patch does not work because you did not avoid
> running the while-loop in a subshell.
> 
> It is well described in  this page:
> https://riptutorial.com/bash/example/26955/to-avoid-usage-of-a-sub-shell
> 

I didn't know that. Then, adding below diff will work.

@@ -24,7 +24,7 @@ exit_code=0
 # symbol_types is fine because export_symbols will remain empty.
 result=$(${NM} ${1} 2>&1) || die "${result}"

-echo "${result}" | while read value type name
+while read value type name
 do
        # Skip the line if the number of fields is less than 3.
        #
@@ -48,7 +48,9 @@ do
        if [[ ${name} == __ksymtab_* ]]; then
                export_symbols+=(${name#__ksymtab_})
        fi
-done
+done <<EOF
+"${result}"
+EOF

 for name in "${export_symbols[@]}"
 do

> 
> 
> I will send a working patch with a proper commit log.

OK. "[PATCH] scripts/check-local-export: avoid 'wait $!' for process substitution" works.

Thank you.