I apologize if this is a stupid question, but I would like MPICH to crash and burn rather than terminate gently when an error occurs so that I can gdb bt it to know where the error is in my program, since I am absolutely certain that this error is in the application and not MPICH. Ideally, I would be able to select the failure mode at runtime, e.g. MPICH_FAILURE_MODE={hard,soft}, so that I can get either the nice MPICH trace when I think MPICH is the problem and a brutal light-the-machine-room-on-fire-and-abort-the-universe error when I think it's my fault. Thanks, Jeff <running in gdb> Assertion failed in file ../src/mpi/coll/helper_fns.c at line 81: FALSE memcpy argument memory ranges overlap, dst_=0x101401000 src_=0x101401000 len_=400 internal ABORT - process 0 Fatal error in MPI_Win_free: Other MPI error, error stack: MPI_Win_free(134)..........: MPI_Win_free(win=0x10000b394) failed MPIDI_CH3_SHM_Win_free(103): pthread mutex routine failed (Resource busy) Program exited with code 01. (gdb) bt $ mpichversion MPICH Version: 3.1b2 MPICH Release date: unreleased development copy MPICH Device: ch3:nemesis MPICH configure: CC=clang CXX=clang++ FC=/bin/false --disable-fc --disable-f77 --enable-threads --enable-g --with-pm=hydra --prefix=/opt/mpich/dev/clang MPICH CC: clang -g -O2 MPICH CXX: clang++ -g -O2 MPICH F77: no -g MPICH FC: no -g -- Jeff Hammond [email protected]