From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13179 invoked by alias); 25 Sep 2010 16:49:58 -0000 Received: (qmail 13169 invoked by uid 22791); 25 Sep 2010 16:49:58 -0000 X-SWARE-Spam-Status: No, hits=-2.5 required=5.0 tests=ALL_TRUSTED,AWL,BAYES_00 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; Sat, 25 Sep 2010 16:49:51 +0000 From: "hp at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug rtl-optimization/45792] New: [4.6 Regression]: cris-elf build failure (hangs) due to fix for PR44374 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: rtl-optimization X-Bugzilla-Keywords: build X-Bugzilla-Severity: normal X-Bugzilla-Who: hp at gcc dot gnu.org 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: X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated Content-Type: text/plain; charset="UTF-8" MIME-Version: 1.0 Date: Sat, 25 Sep 2010 19:06:00 -0000 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: 2010-09/txt/msg02786.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45792 Summary: [4.6 Regression]: cris-elf build failure (hangs) due to fix for PR44374 Product: gcc Version: 4.6.0 Status: UNCONFIRMED Keywords: build Severity: normal Priority: P3 Component: rtl-optimization AssignedTo: unassigned@gcc.gnu.org ReportedBy: hp@gcc.gnu.org CC: bernds@gcc.gnu.org Host: x86_64-unknown-linux-gnu Target: cris-*-* Created attachment 21882 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=21882 Preprocessed dtoa.c At r164551 the tree built with few regressions. At r164560 building newlib/libc/stdlib/dtoa.c hangs (cpu-time > 38 hours) and at r164619 the build is at a similar state (didn't wait 38 hours, but see below). Attaching a gdb-session to the running cc1 at r164619 shows an infinite loop in gcc/emit-rtl.c:reorder_insns: 4027 for (x = from; x != NEXT_INSN (to); x = NEXT_INSN (x)) 4028 if (!BARRIER_P (x)) 4029 df_insn_change_bb (x, bb); But "x" is bogus; it seems to have been deleted or at least removed from the insn stream: (insn 2210 2210 2210 239 (set (cc0) (compare (reg/v/f:SI 3 r3 [orig:95 mlo ] [95]) (reg/v/f:SI 4 r4 [orig:97 mhi ] [97]))) /tmp/hpautotest-gcc1/gcc/newlib/libc/stdlib/dtoa.c:808 11 {*cmpsi} (nil)) The call to df_insn_change_bb takes the (old_bb == new_bb) early return. Author of suspect patch in revision range CC:ed. Preprocessed dtoa.c attached. Compile with -O2.