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From: Jim Meyering <jim@meyering.net>
Newsgroups: gmane.linux.lib.musl.general,gmane.comp.lib.gnulib.bugs
Subject: Re: musl, printf out-of-memory test
Date: Wed, 20 Jun 2012 13:00:30 +0200
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Cc: Rich Felker <dalias@aerifal.cx>,  musl@lists.openwall.com,  bug-gnulib@gnu.org
To: Bruno Haible <bruno@clisp.org>
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Bruno Haible wrote:
> Rich Felker wrote:
>> The problem was an obscure pointer-arithmetic overflow ...
>> where the stack pointer is near the 4GB boundary.
>
> This explains also why it occurred only with a certain probability
> outside gdb, but with 100% probability from within gdb: Apparently gdb
> runs the program without address space layout randomization.

That is correct.  It is a feature of gdb-7.0 and newer.
You can inspect (watch/break-at/etc.) the same address and expect it
to refer to the same memory location in multiple invocations.
This makes gdb's command-line history even more useful.