From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13988 invoked by alias); 27 Mar 2013 12:47:10 -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 13921 invoked by uid 48); 27 Mar 2013 12:47:05 -0000 From: "hubicka at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug lto/55102] The options -flto and -On do not behave as described in GCC docs Date: Wed, 27 Mar 2013 12:47:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: lto X-Bugzilla-Keywords: documentation, lto, missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: hubicka 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: --- 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" MIME-Version: 1.0 X-SW-Source: 2013-03/txt/msg02014.txt.bz2 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55102 --- Comment #3 from Jan Hubicka 2013-03-27 12:47:04 UTC --- Doing IPA analysis at -O0 for LTO streaming won't really solve the fact that functions are not early optimized. I would vote for at least issuing a waning when LTOing -O0 objects into -On, n>=1 LTO binary or simply declaring -O0 to be non-LTO only. But indeed, we probably should make analysis/summary streaming of all IPA passes so -fno-ipa-cp and such works as expected all the time. I have patch fot that somewhere already. We probably should lean the route of streaming the options used and honoring them rather than taking whatever is passed to linker...