From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 16701 invoked by alias); 22 Jul 2013 22:03:12 -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 Received: (qmail 11885 invoked by uid 48); 22 Jul 2013 22:01:08 -0000 From: "jakub at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/57661] [4.9 Regression] ICE: SIGSEGV in verify_ssa Date: Mon, 22 Jul 2013 22:03:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: middle-end X-Bugzilla-Version: 4.9.0 X-Bugzilla-Keywords: ice-on-valid-code X-Bugzilla-Severity: normal X-Bugzilla-Who: jakub at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 4.9.0 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2013-07/txt/msg01049.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57661 Jakub Jelinek changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jakub at gcc dot gnu.org --- Comment #3 from Jakub Jelinek --- Yeah, ipa-split.c together with MEM_REF gimple_clobber_p and anonymous SSA_NAME cause this. ipa-split intentionally ignores clobber stmts during analysis, because they aren't real stmts, worst case we just ignore them and/or throw them away. If a clobber has a decl on lhs, then the decl is always present and not a problem. If it is a MEM_REF clobber with non-anonymous SSA_NAME, it is also just fine, ipa-split will during the cloning of the fn to *.part.* turn those SSA_NAMEs into SSA_NAME_IS_DEFAULT_DEF ones, and then tree-ssa-live will throw such clobbers away as useless. But anonymous SSA_NAMEs aren't meant to be ever SSA_NAME_IS_DEFAULT_DEF, which causes this problem. Perhaps ipa-split should just fix such SSA_NAMEs up (look up what anonymous SSA_NAMEs have no SSA_NAME_DEFAULT_STMT and remove all clobbers that depend on those and remove those SSA_NAMEs?