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From: Segher Boessenkool <segher@kernel•crashing.org>
To: William Kennington <wak@google•com>
Cc: linuxppc-dev@lists•ozlabs.org
Subject: Re: GCC strcmp optimizations causing valgrind uninitialized conditional jumps
Date: Tue, 3 Jul 2018 13:46:18 -0500	[thread overview]
Message-ID: <20180703184617.GF16221@gate.crashing.org> (raw)
In-Reply-To: <CAPnigKnVTg5UiEfou=ABL2DH31rFyGZ_1qtqevJqPPw-V-E6-A@mail.gmail.com>

Hi!

On Tue, Jul 03, 2018 at 11:26:55AM -0700, William Kennington wrote:
> I've noticed while trying to do some valgrind testing on code linked
> against system libraries that have inlined strcmps that valgrind is
> unhappy about branches depending on uninitialized memory. I've read

The branches here do *not* depend on uninitialised memory.  Valgrind
does not realise that however.  The valgrind people are aware of this
problem.

> Any ideas on how to workaround / fix this?

Does -fno-builtin-strcmp do the trick?


Segher

  reply	other threads:[~2018-07-03 18:46 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-03 18:26 GCC strcmp optimizations causing valgrind uninitialized conditional jumps William Kennington
2018-07-03 18:46 ` Segher Boessenkool [this message]
2018-07-03 18:59   ` William Kennington
2018-07-03 19:18     ` Segher Boessenkool

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