From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 123875 invoked by alias); 12 Aug 2015 20:26:48 -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 123804 invoked by uid 48); 12 Aug 2015 20:26:45 -0000 From: "manu at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/67196] Another false positive from -Wmaybe-uninitialized Date: Wed, 12 Aug 2015 20:26:00 -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: manu at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_status cf_reconfirmed_on cc blocked everconfirmed Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-SW-Source: 2015-08/txt/msg00829.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D67196 Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2015-08-12 CC| |manu at gcc dot gnu.org Blocks| |24639 Ever confirmed|0 |1 --- Comment #1 from Manuel L=C3=B3pez-Ib=C3=A1=C3=B1ez --- For some reason, the uninit pass does not even analyze the predicates and thinks all uses are unguarded (or it doesn't dump it). A shorter testcase: int some_test(int); int test (int n) { int num_captions_in_row =3D 0; int first_caption =3D 0; /* set to zero here */ int first_caption_idx; int i; for (i =3D 0; i < n; i++) { if (some_test (i)) { num_captions_in_row++; first_caption =3D 1; /* only ever set here */ first_caption_idx =3D i; /* set here */ } } /* The guard on "first_caption" here requires we entered the block above that sets "first_caption_idx". */ if (first_caption && num_captions_in_row =3D=3D 1) return first_caption_idx; /* get bogus warning here at -O1 and above */ return 0; } Referenced Bugs: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D24639 [Bug 24639] [meta-bug] bug to track all Wuninitialized issues >>From gcc-bugs-return-494688-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Wed Aug 12 21:00:20 2015 Return-Path: Delivered-To: listarch-gcc-bugs@gcc.gnu.org Received: (qmail 57861 invoked by alias); 12 Aug 2015 21:00:20 -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 Delivered-To: mailing list gcc-bugs@gcc.gnu.org Received: (qmail 57820 invoked by uid 55); 12 Aug 2015 21:00:16 -0000 From: "joseph at codesourcery dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/67172] [5/6 regression] i686-w64-mingw32 dwarf2 bootstrap fails with undefined reference to __EH_FRAME_BEGIN__ Date: Wed, 12 Aug 2015 21:00:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 5.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: joseph at codesourcery dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 5.3 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: 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: 2015-08/txt/msg00830.txt.bz2 Content-length: 831 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67172 --- Comment #4 from joseph at codesourcery dot com --- On Tue, 11 Aug 2015, breedlove.matt at gmail dot com wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67172 > > --- Comment #3 from Matt Breedlove --- > In gcc/defaults.h, it gets defined via: So why does not exactly the same sequence of conditional macro definitions apply when libgcc is being built and so cause your patch to be ineffective, given that libgcc does still include the host-side tm.h until the transition away from host-side target macros in target-side code is complete? (In any case, my point still applies: stop __LIBGCC_EH_FRAME_SECTION_NAME__ being defined if it's incorrect, which means some sort of host-side change.)