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From: "hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/65780] [5/6 Regression] Uninitialized common handling in executables Date: Thu, 16 Apr 2015 11:20:00 -0000 [thread overview] Message-ID: <bug-65780-4-559gI4MmrI@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-65780-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65780 --- Comment #14 from H.J. Lu <hjl.tools at gmail dot com> --- (In reply to Jakub Jelinek from comment #10) > (In reply to H.J. Lu from comment #9) > > Created attachment 35327 [details] > > A different patch > > > > On x86, this issue only shows up with PIE. Here is a different > > patch to treat common symbol defined locally only if the backend > > passes true common_maybe_local. For x86-64, it is true only if > > HAVE_LD_PIE_COPYRELOC is 1. For i386, it is always false. If > > we aren't building PIE, common_maybe_local is true or false > > doesn't make a difference for x86 since the common symbol is > > always referenced normally with copy reloc. For PIE on x86-64, > > common symbol is local only if HAVE_LD_PIE_COPYRELOC is 1. > > + > + /* For common symbol, it is defined locally only if common_maybe_local > + is true. */ > + bool defined_locally = (!DECL_EXTERNAL (exp) > + && (!DECL_COMMON (exp) || common_maybe_local)); > > I think better would be: > bool uninited_common = (DECL_COMMON (exp) > && (DECL_INITIAL (exp) == NULL > || (!in_lto_p && DECL_INITIAL (exp) == > error_mark_node))); > /* For common symbol, it is defined locally only if common_maybe_local > is true. */ > bool defined_locally = (!DECL_EXTERNAL (exp) && (!uninited_common || > common_maybe_local)); > ... > and then use > /* Uninitialized COMMON variable may be unified with symbols > resolved from other modules. */ > if (uninited_common && !resolved_locally) > return false; What does initialized COMMON look like to linker? If it is marked as COMMON symbol to linker, it will be treated the same as uninitialized COMMON symbol. >From gcc-bugs-return-483779-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Thu Apr 16 11:31:42 2015 Return-Path: <gcc-bugs-return-483779-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org> Delivered-To: listarch-gcc-bugs@gcc.gnu.org Received: (qmail 7502 invoked by alias); 16 Apr 2015 11:31:42 -0000 Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: <gcc-bugs.gcc.gnu.org> List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/> List-Post: <mailto:gcc-bugs@gcc.gnu.org> List-Help: <mailto:gcc-bugs-help@gcc.gnu.org> Sender: gcc-bugs-owner@gcc.gnu.org Delivered-To: mailing list gcc-bugs@gcc.gnu.org Received: (qmail 7459 invoked by uid 48); 16 Apr 2015 11:31:38 -0000 From: "schwab@linux-m68k.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/65774] [6.0 regression] FAIL: gcc.dg/builtin-arith-overflow-1.c (internal compiler error) Date: Thu, 16 Apr 2015 11:31:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: tree-optimization X-Bugzilla-Version: 6.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: schwab@linux-m68k.org X-Bugzilla-Status: ASSIGNED X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org X-Bugzilla-Target-Milestone: 6.0 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: <bug-65774-4-xy8wk0odaA@http.gcc.gnu.org/bugzilla/> In-Reply-To: <bug-65774-4@http.gcc.gnu.org/bugzilla/> References: <bug-65774-4@http.gcc.gnu.org/bugzilla/> 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: 2015-04/txt/msg01331.txt.bz2 Content-length: 167 https://gcc.gnu.org/bugzilla/show_bug.cgi?ide774 --- Comment #3 from Andreas Schwab <schwab@linux-m68k.org> --- wi::sext has undefined behaviour with offset == 0.
next prev parent reply other threads:[~2015-04-16 11:20 UTC|newest] Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-04-15 22:29 [Bug target/65780] New: [5 " jakub at gcc dot gnu.org 2015-04-15 22:30 ` [Bug target/65780] " jakub at gcc dot gnu.org 2015-04-15 23:01 ` james410 at cowgill dot org.uk 2015-04-15 23:13 ` hjl.tools at gmail dot com 2015-04-15 23:41 ` hjl.tools at gmail dot com 2015-04-16 0:37 ` amodra at gmail dot com 2015-04-16 2:10 ` hjl.tools at gmail dot com 2015-04-16 2:38 ` hjl.tools at gmail dot com 2015-04-16 3:22 ` [Bug target/65780] [5 Regression] Uninitialized common handling in PIE hjl.tools at gmail dot com 2015-04-16 3:28 ` [Bug target/65780] [5 Regression] Uninitialized common handling in executables amodra at gmail dot com 2015-04-16 4:32 ` hjl.tools at gmail dot com 2015-04-16 7:33 ` jakub at gcc dot gnu.org 2015-04-16 7:39 ` [Bug target/65780] [5/6 " rguenth at gcc dot gnu.org 2015-04-16 7:46 ` jakub at gcc dot gnu.org 2015-04-16 11:09 ` jakub at gcc dot gnu.org 2015-04-16 11:12 ` hjl.tools at gmail dot com 2015-04-16 11:20 ` hjl.tools at gmail dot com [this message] 2015-04-16 11:40 ` hjl.tools at gmail dot com 2015-04-16 11:44 ` jakub at gcc dot gnu.org 2015-04-16 11:46 ` hjl.tools at gmail dot com 2015-04-16 11:53 ` hjl.tools at gmail dot com 2015-04-16 12:12 ` jakub at gcc dot gnu.org 2015-04-16 12:33 ` hjl.tools at gmail dot com 2015-04-16 12:41 ` jakub at gcc dot gnu.org 2015-04-16 13:08 ` hjl.tools at gmail dot com 2015-04-16 13:10 ` jakub at gcc dot gnu.org 2015-04-16 13:16 ` hjl.tools at gmail dot com 2015-04-16 15:36 ` jakub at gcc dot gnu.org 2015-04-16 16:09 ` hjl.tools at gmail dot com 2015-04-16 18:14 ` law at redhat dot com 2015-04-16 18:33 ` hjl.tools at gmail dot com 2015-04-16 18:36 ` hjl.tools at gmail dot com 2015-04-16 19:20 ` law at redhat dot com 2015-04-16 19:28 ` hjl.tools at gmail dot com 2015-04-16 21:03 ` jakub at gcc dot gnu.org 2015-04-16 22:02 ` hjl.tools at gmail dot com 2015-04-17 16:12 ` law at redhat dot com 2015-04-17 16:26 ` [Bug target/65780] [5 " hjl.tools at gmail dot com 2015-04-17 16:30 ` jakub at gcc dot gnu.org 2015-04-17 16:36 ` hjl at gcc dot gnu.org 2015-04-17 16:37 ` hjl.tools at gmail dot com 2015-04-17 21:14 ` dominiq at lps dot ens.fr 2015-04-17 21:54 ` hjl at gcc dot gnu.org 2015-04-17 21:55 ` hjl at gcc dot gnu.org 2015-04-17 23:16 ` howarth.at.gcc at gmail dot com 2015-04-18 5:36 ` jakub at gcc dot gnu.org 2015-04-21 14:14 ` evstupac at gmail dot com 2015-04-21 14:18 ` jakub at gcc dot gnu.org 2015-05-11 7:09 ` jakub at gcc dot gnu.org 2015-05-11 7:14 ` jakub at gcc dot gnu.org
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