From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH] valgrind: ignore SSE-based strlen invalid reads
Date: Wed, 16 Mar 2011 05:52:14 -0500
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Cc: git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>
To: Carlos =?utf-8?Q?Mart=C3=ADn?= Nieto <cmn@elego.de>
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Carlos Mart=C3=ADn Nieto wrote:

> The GNU C Library (glibc) uses SSE instructions to make strlen (among
> others) faster, loading 4 bytes at a time and reading past the end of
> the allocated memory. This read is safe and when the strlen function
> is inlined, it is (obviously) not replaced by valgrind, which reports
> a false-possitive.

This still makes no sense to me.  How is it possible to inline a
function from glibc?  When I look in /usr/include/string.h, I see

extern size_t strlen (__const char *__s)
     __THROW __attribute_pure__ __nonnull ((1));

> Tell valgrind to ignore this particular error, as the read is, in
> fact, safe.

I'm happy to see a workaround.  I would be even happier if it came
with documentation about which versions of valgrind need it.

Thanks again.
Jonathan