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From: "bugdal at aerifal dot cx" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/55431] Invalid auxv search in ppc linux-unwind code.
Date: Sun, 09 Dec 2012 02:37:00 -0000	[thread overview]
Message-ID: <bug-55431-4-XaK2pzRV91@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-55431-4@http.gcc.gnu.org/bugzilla/>


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55431

--- Comment #2 from Rich Felker <bugdal at aerifal dot cx> 2012-12-09 02:37:19 UTC ---
The ABI issue is a dependency on an undocumented part of glibc's ABI behavior
-- I don't see anywhere it's documented that __libc_stack_end points at "argc"
(i.e. the original place the stack pointer points to on program entry), just
some point past the end of the stack, and thus it's conceivable that even in
glibc it could change to point somewhere else. In any case, it's a gratuitous
dependency on glibc internals.

The logic error issue (assuming the initial environ array is still intact) is
of course an outright observable bug even without any incompatible changes at
the libc level.

Do you have any idea why this code was added to begin with? It seems completely
unnecessary.


  parent reply	other threads:[~2012-12-09  2:37 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-21 17:42 [Bug target/55431] New: " bugdal at aerifal dot cx
2012-12-09  0:59 ` [Bug target/55431] " pinskia at gcc dot gnu.org
2012-12-09  2:37 ` bugdal at aerifal dot cx [this message]
2013-02-11  9:12 ` aldot at gcc dot gnu.org
2013-02-11 18:17 ` dje at gcc dot gnu.org
2013-02-11 22:42 ` amodra at gmail dot com
2013-02-12  3:05 ` amodra at gmail dot com
2013-02-12  7:08 ` bugdal at aerifal dot cx
2013-02-12 13:24 ` amodra at gmail dot com
2013-02-12 15:28 ` bugdal at aerifal dot cx
2013-02-15 13:54 ` amodra at gcc dot gnu.org
2013-02-15 13:55 ` amodra at gmail dot com
2013-02-15 13:56 ` amodra at gmail dot com

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