From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 55999 invoked by alias); 10 Apr 2015 18:39:42 -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 55925 invoked by uid 48); 10 Apr 2015 18:39:38 -0000 From: "howarth.at.gcc at gmail dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug bootstrap/65733] New: gcc 4.9.2 suffers bootstrap comparison failures with clang 3.5.1 and later. Date: Fri, 10 Apr 2015 18:39:00 -0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: bootstrap X-Bugzilla-Version: 5.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: howarth.at.gcc at gmail dot com X-Bugzilla-Status: UNCONFIRMED 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_id short_desc product version bug_status bug_severity priority component assigned_to reporter Message-ID: 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/msg00890.txt.bz2 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65733 Bug ID: 65733 Summary: gcc 4.9.2 suffers bootstrap comparison failures with clang 3.5.1 and later. Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: bootstrap Assignee: unassigned at gcc dot gnu.org Reporter: howarth.at.gcc at gmail dot com The Xcode 6.3 release (with Apple Clang 6.1 compilers based on 3.6.0svn) produces bootstrap comparison failures in the gcc 4.9.2 build on x86_64-apple-darwin14. The same bootstrap comparison failure is also seen on x86_64-apple-darwin13 with Xcode 6.2 but using the llvm.org clang 3.5.1, 3.5.2 or 3.6.0 compilers instead of the Apple Clang 6.0 compilers. Comparing stages 2 and 3 warning: gcc/cc1-checksum.o differs warning: gcc/cc1obj-checksum.o differs warning: gcc/cc1objplus-checksum.o differs warning: gcc/cc1plus-checksum.o differs Bootstrap comparison failure! gcc/asan.o differs gcc/attribs.o differs gcc/bitmap.o differs gcc/c/c-decl.o differs gcc/cfg.o differs gcc/coverage.o differs gcc/cp/class.o differs gcc/cp/semantics.o differs gcc/cp/tree.o differs gcc/dse.o differs gcc/dwarf2out.o differs gcc/except.o differs gcc/fortran/trans-common.o differs gcc/ggc-common.o differs gcc/graphite-clast-to-gimple.o differs gcc/graphite.o differs gcc/ipa-profile.o differs gcc/ira-color.o differs gcc/ira-costs.o differs gcc/java/jcf-io.o differs gcc/loop-unroll.o differs gcc/lto-streamer-in.o differs gcc/lto-streamer-out.o differs gcc/objc/objc-act.o differs gcc/objcp/objcp-act.o differs gcc/passes.o differs gcc/plugin.o differs gcc/postreload-gcse.o differs gcc/statistics.o differs gcc/trans-mem.o differs gcc/tree-cfg.o differs gcc/tree-eh.o differs gcc/tree-ssa-ccp.o differs gcc/tree-ssa-coalesce.o differs gcc/tree-ssa-dom.o differs gcc/tree-ssa-live.o differs gcc/tree-ssa-loop-ivopts.o differs gcc/tree-ssa-phiopt.o differs gcc/tree-ssa-pre.o differs gcc/tree-ssa-reassoc.o differs gcc/tree-ssa-threadupdate.o differs gcc/tree-ssa-uncprop.o differs gcc/tree-vectorizer.o differs gcc/valtrack.o differs gcc/vtable-verify.o differs Makefile:20180: recipe for target 'compare' failed The observation, that the llvm.org clang 3.5.1 or later compilers along side Xcode 6.2 produces the same bootstrap comparison failure, eliminates the cctools changes in Xcode 6.3 as the culprit and points to miscompilation of the stage1 compiler instead. Reducing the optimization of the stage1 bootstrap with STAGE1_CFLAGS="-O0 -g" and STAGE1_CXXFLAGS="-O0 -g" doesn't eliminate the bootstrap comparison failure. Interestingly, current gcc trunk 5.0svn doesn't exhibit the bootstrap comparison failure (with the stock build or using --enable-checking=release).