Hi, I have a problem when trying to use gdb in mpich-3.0.4 MPICH is configured with: ./configure --prefix=/homes/fisaila/software/mpich --enable-g=all --enable-fast=O0 --enable-shared When running a the cpi from examples directory with: mpiexec -np 1 xterm -e gdb cpi I am getting the xterm window correctly and: (gdb) r Starting program: /nfs2/fisaila/software/mpich-3.0.4/examples/cpi [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [cli_0]: write_line error; fd=6 buf=:cmd=init pmi_version=1 pmi_subversion=1 : system msg for write_line failure : Bad file descriptor [cli_0]: Unable to write to PMI_fd [cli_0]: write_line error; fd=6 buf=:cmd=get_appnum : system msg for write_line failure : Bad file descriptor Fatal error in MPI_Init: Other MPI error, error stack: MPIR_Init_thread(433): MPID_Init(139).......: channel initialization failed MPID_Init(421).......: PMI_Get_appnum returned -1 [Inferior 1 (process 14215) exited with code 01] The gdb version is: gdb -v GNU gdb (Ubuntu/Linaro 7.4-2012.04-0ubuntu2.1) 7.4-2012.04 Any suggestion? Thanks Florin