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From: "msebor at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug sanitizer/65479] sanitizer stack trace missing frames past #0 on powerpc64
Date: Fri, 10 Apr 2015 02:14:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65479

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|powerpc64*-linux-*          |

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
The bug in backtrace_qsort is actually worse than the regression introduced in
r208403.  There is a fundamental problem with relying on the addresses of the
array elements to maintain stability.  Either the algorithm needs to be
replaced with a stable one like Merge Sort, or a new data member needs to be
introduced into struct line to reflect their initial order.  I suspect the
latter alternative will be cheaper in terms of resources (i.e., less memory and
faster sort time).

This also means that the aspect of the bug isn't powerpc specific.  It only
happens to manifest in the testsuite runs on that target.