From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/5108 Path: news.gmane.org!not-for-mail From: Thomas Petazzoni Newsgroups: gmane.linux.lib.musl.general Subject: Re: Broken GCC versions: 4.8.2 and 4.9.0 Date: Sun, 11 May 2014 18:10:20 +0200 Organization: Free Electrons Message-ID: <20140511181020.0a8b66f1@free-electrons.com> References: <20140511010503.GA6502@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 1399824652 32581 80.91.229.3 (11 May 2014 16:10:52 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 11 May 2014 16:10:52 +0000 (UTC) Cc: dalias@libc.org To: musl@lists.openwall.com Original-X-From: musl-return-5113-gllmg-musl=m.gmane.org@lists.openwall.com Sun May 11 18:10:47 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 1WjWKr-0007Pf-SP for gllmg-musl@plane.gmane.org; Sun, 11 May 2014 18:10:45 +0200 Original-Received: (qmail 11513 invoked by uid 550); 11 May 2014 16:10:44 -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 11503 invoked from network); 11 May 2014 16:10:43 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on mail.free-electrons.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.3.2 In-Reply-To: <20140511010503.GA6502@brightrain.aerifal.cx> X-Mailer: Claws Mail 3.9.3 (GTK+ 2.24.20; x86_64-pc-linux-gnu) Xref: news.gmane.org gmane.linux.lib.musl.general:5108 Archived-At: Dear Rich Felker, On Sat, 10 May 2014 21:05:03 -0400, Rich Felker wrote: > It's come to my attention that GCC versions 4.8.2 and 4.9.0 are > performing invalid optimizations that result in a broken musl > libc.a/libc.so. It's not clear yet whether there's a good workaround, > or whether we should attempt to work around the problem, so for now, > please just be aware that these versions of GCC cannot be used to > compile musl. Using them to compile programs against musl should not > be a problem. I'll post more details later. The short version is that > it's making incorrect assumptions about the reachability of global > variables that have a local weak definition and an external strong > one. Hum, interesting. I've recently tested gcc 4.8.2 + musl on ARM, and gcc 4.9.0 + musl on i386, and I could boot a minimal musl+Busybox system under Qemu perfectly fine. Maybe the problem you refer to only affects certain parts of libc.a/libc.so? Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com