Re: 64bit: segfault on program exit

[marco atzeri <marco dot atzeri at gmail dot com>]

On 4/2/2013 10:59 AM, Corinna Vinschen wrote:
> Hi Marco,
>
> On Apr  1 17:11, marco atzeri wrote:
> > I am building and testing openmpi-1.7.0rc9 on
> >    CYGWIN_NT-6.1 1.7.18(0.263/5/3) 2013-03-28 22:07 x86_64 Cygwin
> > every looks fine except when all the processes on several cores
> > end and should return to lunching program, something go wrong
> > (of course on 32bit everyhing is OK)
> >
> > Attached stackdump.
>
> Not all 64 bit issues are Cygwin's fault.  It's not clear in your
> case, but it is pretty clear that this happens in a DLL other than
> the Cygwin DLL.  Look at the stack trace:
>
> > Stack trace:
> > Frame        Function    Args
> > 0000022A630  00488F23380 (004CCD00004, 0060008C820, 00600082970, 0000022CCF0)
> > 00600012500  00488F1C48C (00000000000, 0000022AB10, 00180134344, 00000000000)
> > 0000022A900  0010040234B (0000022AB10, 00000000000, 00000000000, 0000022AB80)
> > 0000022AAC0  001004010F3 (0000022AB10, 00000000000, 00000000030, 30001000000FF00)
> > 0000022AB80  001800478A7 (00000000000, 00000000000, 00000000000, 00000000000)
> > 00000000000  0018004576B (00000000000, 00000000000, 00000000000, 00000000000)
> > 00000000000  0018004592F (00000000000, 00000000000, 00000000000, 00000000000)
> > 00000000000  00100407CB1 (00000000000, 00000000000, 00000000000, 00000000000)
> > 00000000000  00100401010 (00000000000, 00000000000, 00000000000, 00000000000)
> > 00000000000  0007710652D (00000000000, 00000000000, 00000000000, 00077189300)
> > 00000000000  0007733C521 (00000000000, 00000000000, 00000000000, 00077189300)
> > End of stack trace
>
> The function addresses starting with 0x4 are distro DLLs.  So the crash
> occurs in a DLL at address 0x4:88F23380.  The easiest way to find out
> which DLL is the culprit, is this:  Call `rebase -i /bin/*.dll' and see
> which DLL covers the 0x4:88Fxxxxx addresses.

it is one of the openmpi dll.
> The next addresses on the stack are applicaton addresses (0x1:0xxxxxxx)
> The Cygwin DLL itself only shows up in the 6th frame (0x1:8xxxxxxx).
> This is apparently the DLL entry point which ultimately calls the
> application's main function.

unfortunately GDB freezes before hitting breakpoints in code
portion where the segfault is supposed to be.
So something is fishy and GDB seems unable to catch it


> Did you see my mail describing the memory layout on the
> cygwin-developers list?  This is a bit helpful I hope:
>
>    http://cygwin.com/ml/cygwin-developers/2013-02/msg00027.html
>
>
> Corinna

Thanks
Marco