From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11980 invoked by alias); 27 Jun 2012 05:42:41 -0000 Received: (qmail 11878 invoked by uid 22791); 27 Jun 2012 05:42:41 -0000 X-SWARE-Spam-Status: No, hits=-4.3 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00,KHOP_THREADED,TW_TM X-Spam-Check-By: sourceware.org Received: from localhost (HELO gcc.gnu.org) (127.0.0.1) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 27 Jun 2012 05:42:27 +0000 From: "aoliva at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug debug/53740] [4.8 Regression] --enable-checking=yes,rtl bootstrap failure with ada Date: Wed, 27 Jun 2012 05:42:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: debug X-Bugzilla-Keywords: ice-checking, ice-on-valid-code X-Bugzilla-Severity: normal X-Bugzilla-Who: aoliva at gcc dot gnu.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: aoliva at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.8.0 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" Content-Transfer-Encoding: quoted-printable 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: 2012-06/txt/msg01764.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D53740 --- Comment #6 from Alexandre Oliva 2012-06-27 = 05:42:26 UTC --- The bug was introduced in r188527, with the conditionalization of calling insert_dead_debug_temp in the =E2=80=9Celse=E2=80=9D clause, so that we wou= ld no longer insert debug temps for sets that were not themselves dead, but that were used in d= ebug stmts after their death. This caused a chain of debug temps to be incorrec= tly introduced, which ended up triggering the problem. Now, there is indeed a bug in the way we deal with multiregs: we're happily using paradoxical SUBREGs to extend the value stored in a single REG to determine the value of the whole multi-reg expression. We only refrained f= rom doing so if the SET was already a SUBREG, but we had to do that for REGs to= o. In the patch I'm testing now, I fix both problems. Will post soon.