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 Sat, 11 Apr 2020 12:39:00 +0300 (MSK)
Date: Sat, 11 Apr 2020 12:38:58 +0300
From: Alexander Turenko <alexander.turenko@tarantool.org>
Message-ID: <20200411093858.nwsnbhjjcqi4qqri@tkn_work_nb>
References: <5f71273b0240cfc9cb1ee6f6473e30850650be25.1586557519.git.alexander.turenko@tarantool.org>
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Subject: Re: [Tarantool-patches] [PATCH] popen: fix 'may be clobbered'
	compiler warning
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To: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: tarantool-patches@dev.tarantool.org

On Sat, Apr 11, 2020 at 10:30:26AM +0300, Cyrill Gorcunov wrote:
> On Sat, Apr 11, 2020 at 01:28:07AM +0300, Alexander Turenko wrote:
> > I guess a compiler assumes that the code inside vfork may use the stack
> > slot that corresponds the variable and so clobber it. The recent commit
> > 07a07b3cc7b85375d20b3fc6ca1e5060304f337b ('popen: decouple logger fd
> > from stderr') adds read from this variable after vfork() in the parent
> > process.
> > 
> > The warning is produced on RelWithDebInfo build with LTO enabled on GCC
> > 9.2.0 (locally) and on GCC 8.3.0 (in CI).
> > 
> > Part of #4031
> Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>

Pushed to master.

WBR, Alexander Turenko.