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Date: Tue, 3 Jul 2018 13:46:18 -0500
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
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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