No, I don't really have any idea what it's doing. You have to add manual sleeps and attach another instance of gdb if you want to step through the child, since I also can't get follow-fork-mode child to work. I only tried that once, and it segfaulted accessing the zero pointer destroying the stack in the process. I haven't done manual stepping or printf searches, so I don't know where in MPI_Init it breaks.
I'm trying to install gdb 7.5.1 now (a nontrivial process on Mac, unfortunately) to see if that fixes it. Geoffrey On Thu, Feb 21, 2013 at 4:28 PM, Ralph Castain <r...@open-mpi.org> wrote: > Hmmm...how about that? Yeah, it doesn't work with the devel trunk either - > I'd missed that point. > > No idea why, I'm afraid - never tried it before. Are you sure it "crashes"? > I'm still getting a child status of "0", but no message output. My guess is > that the I/O is being lost for some reason. > > On Feb 21, 2013, at 4:09 PM, Geoffrey Irving <irv...@naml.us> wrote: > >> Actually, I don't see it printing "We're an MPI program!" under gdb, >> which means it isn't working. >> >> Geoffrey >> >> On Thu, Feb 21, 2013 at 4:07 PM, Ralph Castain <r...@open-mpi.org> wrote: >>> Hmmm...works with 1.6.4 for me on Mac 10.8.2: >>> >>> Ralphs-iMac:v1.6 rhc$ ./fork-bug >>> We're an MPI program! >>> child status = 0 >>> Ralphs-iMac:v1.6 rhc$ gdb ./fork-bug >>> GNU gdb 6.3.50-20050815 (Apple version gdb-1820) (Sat Jun 16 02:40:11 UTC >>> 2012) >>> Copyright 2004 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 "x86_64-apple-darwin"...Reading symbols for >>> shared libraries ... done >>> >>> (gdb) r >>> Starting program: /Volumes/RHCHD/rhc/openmpi/v1.6/fork-bug >>> Reading symbols for shared libraries ++............................. done >>> child status = 0 >>> >>> Program exited normally. >>> (gdb) >>> >>> Afraid I have no idea why you might be hitting the problem, though... >>> >>> >>> On Feb 21, 2013, at 3:50 PM, Geoffrey Irving <irv...@naml.us> wrote: >>> >>>> The singleton fork/exec itself is fine, since normal MPI programs work >>>> under gdb (e.g., fork-bug.c without the fork). gdb is has >>>> follow-fork-mode set to parent, so it's odd that gdb is looking at the >>>> child process's trickery at all. >>>> >>>> I've confirmed that it's still broken under 1.6.4, unfortunately. >>>> >>>> Geoffrey >>>> >>>> On Thu, Feb 21, 2013 at 3:36 PM, Ralph Castain <r...@open-mpi.org> wrote: >>>>> Singletons fork/exec a daemon to support them - my guess is that gdb may >>>>> not like it on your machine? >>>>> >>>>> FWIW - it runs fine for me using the developer's trunk. You might try >>>>> with 1.6.4 in case it's a bug in 1.6.0 >>>>> >>>>> >>>>> On Feb 21, 2013, at 3:18 PM, Geoffrey Irving <irv...@naml.us> wrote: >>>>> >>>>>> The attached program illustrates the problem. It forks, and the child >>>>>> calls MPI_Init. This works fine unless I'm inside gdb. Inside gdb, >>>>>> MPI_Init silently crashes. >>>>>> >>>>>> I'm using OpenMPI 1.6.0 on Mac 10.8.2. I'm running the program >>>>>> directly, not through mpirun. >>>>>> >>>>>> Any ideas what might be wrong? >>>>>> >>>>>> Thanks, >>>>>> Geoffrey >>>>>> >>>>>> cone:scratch% /usr/local/bin/mpicc -o fork-bug fork-bug.c >>>>>> cone:scratch% ./fork-bug >>>>>> We're an MPI program! >>>>>> child status = 0 >>>>>> cone:scratch% gdb ./fork-bug >>>>>> gdb ./fork-bug >>>>>> GNU gdb 6.3.50-20050815 (Apple version gdb-1824) (Thu Nov 15 10:42:43 >>>>>> UTC 2012) >>>>>> Copyright 2004 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 "x86_64-apple-darwin"...Reading symbols for >>>>>> shared libraries ... done >>>>>> >>>>>> (gdb) run >>>>>> Reading symbols for shared libraries ++............................. done >>>>>> child status = 5 >>>>>> >>>>>> Program exited normally. >>>>>> (gdb) cone:scratch% >>>>>> <fork-bug.c>_______________________________________________ >>>>>> users mailing list >>>>>> us...@open-mpi.org >>>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users >>>>> >>>>> >>>>> _______________________________________________ >>>>> users mailing list >>>>> us...@open-mpi.org >>>>> http://www.open-mpi.org/mailman/listinfo.cgi/users >>>> _______________________________________________ >>>> users mailing list >>>> us...@open-mpi.org >>>> http://www.open-mpi.org/mailman/listinfo.cgi/users >>> >>> >>> _______________________________________________ >>> users mailing list >>> us...@open-mpi.org >>> http://www.open-mpi.org/mailman/listinfo.cgi/users >> _______________________________________________ >> users mailing list >> us...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/users > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
