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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Peter Steele <psteele@maxiscale.com>
References: <7B9397B189EB6E46A5EE7B4C8A4BB7CB3B5AACBE@MBX03.exg5.exghost.com>
Date: Fri, 26 Mar 2010 13:43:16 +0100
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	(Peter Steele's message of "Fri, 26 Mar 2010 07:33:10 -0500")
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Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>
Subject: Re: Puzzling stack trace
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Peter Steele <psteele@maxiscale.com> writes:
> #8 0x00000008011ffe8f in malloc () from /lib/libc.so.7
>
> #9 0x000000080127374b in memchr () from /lib/libc.so.7

The stack trace is clearly incorrect:

void *
memchr(const void *s, int c, size_t n)
{
        if (n !=3D 0) {
                const unsigned char *p =3D s;

                do {
                        if (*p++ =3D=3D (unsigned char)c)
                                return ((void *)(p - 1));
                } while (--n !=3D 0);
        }
        return (NULL);
}

Type "frame 9" and see what it says.  If the bug is easily reproducable,
try reproducing it with a debugging version of libc (buildworld with
DEBUG_FLAGS=3D-g)

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no