Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Date: Tue, 30 Dec 2003 16:43:09 -0500 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: Re: 1.5.6-pre: Occasional bad memory accesses within cygwin1.dll Message-ID: <20031230214309.GA30386@redhat.com> Mail-Followup-To: cygwin AT cygwin DOT com References: <010b01c3cd5a$a138c9b0$d6e28351 AT starfruit> <20031230033711 DOT GA20304 AT redhat DOT com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i X-IsSubscribed: yes Reply-To: cygwin AT cygwin DOT com On Tue, Dec 30, 2003 at 02:36:12PM -0600, Brian Ford wrote: >On Mon, 29 Dec 2003, Christopher Faylor wrote: > >> On Sun, Dec 28, 2003 at 03:52:33PM -0000, Max Bowsher wrote: >> >I installed a self-built cygwin HEAD version - mostly it works fine, but it >> >causes odd failures during builds (speculation: race when many processes >> >being created and destroyed?) >> > >> >The most common failure is a Windows error box: >> > >> >The instruction at "0x6108621a" references memory at "0x610030b0". The >> >memory could not be written. >> > >> >(These addresses are constant.) >> > >> >$ addr2line -e /bin/cygwin1.dll 0x6108621a 0x610030b0 >> >.../src/winsup/cygwin/shm.cc:331 >> >.../src/winsup/cygwin/cygthread.cc:34 >> >> This isn't too useful, unfortunately. The line numbers are an artifact >> of the fact that there is no STABS information in the generated asm in >> 'sigfe.s'. Can you get an assembly listing of the lines around this >> instruction? >> >I think this is the same problem. It shows up all over the place for me >in the testsuite. > >$ env >GNU gdb 5.3 >Copyright 2002 Free Software Foundation, Inc. >GDB is free software, covered by the GNU General Public License, and you are >welcome to change it and/or distribute copies of it under certain conditions. >Type "show copying" to see the conditions. >There is absolutely no warranty for GDB. Type "show warranty" for details. >This GDB was configured as "i686-pc-cygwin"... >(gdb) r >Starting program: >/home/ford/downloads/cygb2/i686-pc-cygwin/winsup/testsuite/testsuite/checksignal.exe > >Program received signal SIGSEGV, Segmentation fault. >0x6108bcad in _sigfe () >Current language: auto; currently c++ >(gdb) bt >#0 0x6108bcad in _sigfe () >#1 0xffffffff in ?? () >#2 0x00402b1f in cygwin_crt0 (f=0x401134
) > at ../../../../cygwin/winsup/cygwin/lib/cygwin_crt0.c:24 >#3 0x0040103c in mainCRTStartup () >#4 0x77f1bb7b in _system_dlls__ () >(gdb) disassemble >Dump of assembler code for function _sigfe: >0x6108bc90 <_sigfe>: push %edx >0x6108bc91 <_sigfe+1>: mov %fs:0x4,%eax >0x6108bc97 <_sigfe+7>: mov $0x4,%edx >0x6108bc9c <_sigfe+12>: xadd %edx,0xffffeff8(%eax) >0x6108bca3 <_sigfe+19>: lea 0x6108bcb1,%eax >0x6108bca9 <_sigfe+25>: xchg %eax,0x8(%esp,1) >0x6108bcad <_sigfe+29>: mov %eax,(%edx) >0x6108bcaf <_sigfe+31>: pop %edx >0x6108bcb0 <_sigfe+32>: ret >End of assembler dump. >(gdb) $edx? cgf -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/