From mboxrd@z Thu Jan 1 00:00:00 1970 From: Markus Trippelsdorf Subject: git-blame segfault Date: Mon, 2 Dec 2013 13:57:48 +0100 Message-ID: <20131202125748.GA275@x4> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Mon Dec 02 14:04:42 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1VnTB3-0000gt-Dy for gcvg-git-2@plane.gmane.org; Mon, 02 Dec 2013 14:04:41 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753093Ab3LBNEg (ORCPT ); Mon, 2 Dec 2013 08:04:36 -0500 Received: from ud10.udmedia.de ([194.117.254.50]:52967 "EHLO mail.ud10.udmedia.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752556Ab3LBNEd (ORCPT ); Mon, 2 Dec 2013 08:04:33 -0500 X-Greylist: delayed 402 seconds by postgrey-1.27 at vger.kernel.org; Mon, 02 Dec 2013 08:04:33 EST DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=mail.ud10.udmedia.de; h= date:from:to:subject:message-id:mime-version:content-type; s= beta; bh=oLv8o9K6LDwFyUJBpMp/Ur/hC3v8CxnDi8kEuzxJ6qY=; b=uBRkPOU TV6RQiCPfkJVb4upxRefHhvUvS3V/zdTnocu4nxgSmwvyv0uiQ4CQuEEozB6dX59 9wfVqTQDfThnVEVufLiZPY9e3AvEpVsqdTlSZfbij5dnV5Tj5D33eOIr4bseQWGs eBxdq24MK7imxCZCXHej3QemHsAeYFliToPw= Received: (qmail 3534 invoked from network); 2 Dec 2013 13:57:49 +0100 Received: from unknown (HELO x4) (ud10?360p3@91.64.96.185) by mail.ud10.udmedia.de with ESMTPSA (DHE-RSA-AES256-SHA encrypted, authenticated); 2 Dec 2013 13:57:49 +0100 Content-Disposition: inline Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: When git is compiled with current gcc and "-march=native" git-blame segfaults: For example: % gdb --args /var/tmp/git/git-blame gcc/tree-object-size.c ... Program received signal SIGSEGV, Segmentation fault. 0x0000000000000000 in ?? () (gdb) bt #0 0x0000000000000000 in ?? () #1 0x000000000051240d in xdl_emit_hunk_hdr (s1=s1@entry=30, c1=, s2=s2@entry=30, c2=c2@entry=6, func=func@entry=0x7fffffffd2d8 "", funclen=0, ecb=ecb@entry=0x7fffffffd580) at xdiff/xutils.c:460 #2 0x0000000000512af7 in xdl_emit_diff (xe=0x7fffffffd390, xscr=, ecb=0x7fffffffd580, xecfg=0x7fffffffd590) at xdiff/xemit.c:237 #3 0x0000000000510a5d in xdl_diff (mf1=mf1@entry=0x7fffffffd510, mf2=mf2@entry=0x7fffffffd520, xpp=xpp@entry=0x7fffffffd570, xecfg=xecfg@entry=0x7fffffffd590, ecb=ecb@entry=0x7fffffffd580) at xdiff/xdiffi.c:601 #4 0x000000000050b005 in xdi_diff (mf1=, mf2=, xpp=xpp@entry=0x7fffffffd570, xecfg=xecfg@entry=0x7fffffffd590, xecb=xecb@entry=0x7fffffffd580) at xdiff-interface.c:136 #5 0x00000000004104df in diff_hunks (file_a=, file_b=, ctxlen=ctxlen@entry=0, hunk_func=hunk_func@entry=0x411320 , cb_data=cb_data@entry=0x7fffffffd830) at builtin/blame.c:105 #6 0x0000000000412b54 in pass_blame_to_parent (parent=0x11da810, target=0x11dab50, sb=0x7fffffffd6e0) at builtin/blame.c:815 #7 pass_blame (opt=0, origin=0x11dab50, sb=0x7fffffffd6e0) at builtin/blame.c:1281 #8 assign_blame (opt=, sb=0x7fffffffd6e0) at builtin/blame.c:1559 #9 cmd_blame (argc=, argv=, prefix=) at builtin/blame.c:2523 #10 0x00000000004060b5 in run_builtin (argv=0x7fffffffe528, argc=2, p=0x578bd8 ) at git.c:314 #11 handle_internal_command (argc=2, argv=0x7fffffffe528) at git.c:478 #12 0x0000000000405772 in main (argc=2, av=) at git.c:575 (gdb) up #1 0x000000000051240d in xdl_emit_hunk_hdr (s1=s1@entry=30, c1=, s2=s2@entry=30, c2=c2@entry=6, func=func@entry=0x7fffffffd2d8 "", funclen=0, ecb=ecb@entry=0x7fffffffd580) at xdiff/xutils.c:460 460 if (ecb->outf(ecb->priv, &mb, 1) < 0) (gdb) l 455 } 456 buf[nb++] = '\n'; 457 458 mb.ptr = buf; 459 mb.size = nb; 460 if (ecb->outf(ecb->priv, &mb, 1) < 0) 461 return -1; 462 463 return 0; 464 } (gdb) p *ecb $1 = { priv = 0x7fffffffd830, outf = 0x0 } If I leave xecfg uninitialized in the following function the issue goes away. >>From builtin/blame.c: 94 static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen, 95 xdl_emit_hunk_consume_func_t hunk_func, void *cb_data) 96 { 97 xpparam_t xpp = {0}; 98 xdemitconf_t xecfg = {0}; 99 xdemitcb_t ecb = {NULL}; 100 101 xpp.flags = xdl_opts; 102 xecfg.ctxlen = ctxlen; 103 xecfg.hunk_func = hunk_func; 104 ecb.priv = cb_data; 105 return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb); 106 } 107 I'm not sure if this a git bug or a gcc bug. In any case I've opened a gcc bug-report here: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59363 -- Markus