From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 3001 invoked by alias); 9 Dec 2012 02:37:34 -0000 Received: (qmail 2939 invoked by uid 48); 9 Dec 2012 02:37:20 -0000 From: "bugdal at aerifal dot cx" 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 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: bugdal at aerifal dot cx X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2012-12/txt/msg00832.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55431 --- Comment #2 from Rich Felker 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.