From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/5116 Path: news.gmane.org!not-for-mail From: Natanael Copa Newsgroups: gmane.linux.lib.musl.general Subject: Re: Broken GCC versions: 4.8.2 and 4.9.0 Date: Mon, 12 May 2014 11:28:33 +0200 Message-ID: <20140512112833.596ca259@ncopa-desktop.alpinelinux.org> References: <20140511010503.GA6502@brightrain.aerifal.cx> <20140511181020.0a8b66f1@free-electrons.com> <20140511161943.GR26358@brightrain.aerifal.cx> <20140511190320.GV26358@brightrain.aerifal.cx> <20140511212030.GY26358@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Trace: ger.gmane.org 1399886948 29034 80.91.229.3 (12 May 2014 09:29:08 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Mon, 12 May 2014 09:29:08 +0000 (UTC) Cc: dalias@libc.org, James Cloos , Thomas Petazzoni To: musl@lists.openwall.com Original-X-From: musl-return-5121-gllmg-musl=m.gmane.org@lists.openwall.com Mon May 12 11:29:00 2014 Return-path: Envelope-to: gllmg-musl@plane.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1WjmXU-0005xL-MN for gllmg-musl@plane.gmane.org; Mon, 12 May 2014 11:28:52 +0200 Original-Received: (qmail 3168 invoked by uid 550); 12 May 2014 09:28:51 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 3160 invoked from network); 12 May 2014 09:28:50 -0000 In-Reply-To: <20140511212030.GY26358@brightrain.aerifal.cx> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.23; x86_64-alpine-linux-musl) Xref: news.gmane.org gmane.linux.lib.musl.general:5116 Archived-At: On Sun, 11 May 2014 17:20:30 -0400 Rich Felker wrote: > On Sun, May 11, 2014 at 04:08:37PM -0400, James Cloos wrote: > > >>>>> "RF" == Rich Felker writes: > > > > RF> I've tested it on gcc.godbolt.org and others have tested with local > > RF> gcc 4.8.2 and 4.9.0, probably distro-provided (I didn't ask). > > > > I just tried debian-sid's 4.9. That does show the bug. As does their > > gcc-snapshot version (a 4.10 pre). > > > > Perhaps the distro(s) which have the bug with 4.8.2 backported the commit > > where the bug first occurs? > > Sounds plausible. Maybe that will help find the offending commit. I have tried to reproduce the issue on Alpine Linux without success. We have gcc-4.8.2 with lots of patches from gentoo and with a hardened default (default enabled). I have tried run with GCC_SPECS=vanilla (should disable the hardened part) and without the -Os without any difference. It would be interesting to know what patches was used on the affected gcc-4.8.2 systems. > > RF> I wonder if the broken GCC is using isl/cloog > > > > I use the graphite optimizer on my Gentoo box (which generated the > > assembly I quoted). The graphite code is only used when one or more > > of -floop-interchange -floop-strip-mine -floop-block are specified. > > > > Testing with those options doesn't change the results. > > OK, ruled that out then. We also have a patch[1] that will dlopen libcloog-isl.so.4 instead of link to it directly for upgrade purposes. I have tried to build musl with and without libcloog-isl.so.4 installed without it making any difference. > > Rich