Dear MPICH discuss group, Sorry if this is a duplicate, I tried to send it before being subscribed, and am not sure if it ever made it to the list. I am encountering an issue when trying to use lldb with both mpich 3.1 and 3.0.4. The command that generates the error is computer:tests ME$ mpirun -np 1 lldb ./a.out Current executable set to './a.out' (x86_64). (lldb) run run Process 67202 launched: './a.out' (x86_64) [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(467): MPID_Init(140).......: channel initialization failed MPID_Init(422).......: PMI_Get_appnum returned -1 Process 67202 exited with status = 1 (0x00000001) mpich 3.1 was configured with $SRC_DIR/configure \ --prefix=$INSTALL_ROOT/$BUILD_DIR \ --disable-cxx \ --disable-f77 \ --disable-fc \ CC=clang \ CXX=clang++ \ The version of lldb is lldb-310.2.36 The minimal example that shows the problem is #include <mpi.h> int main(int argc, char**argv){ MPI_Init(&argc, &argv); MPI_Finalize(); return 0; } compiled with mpicc Since I know it has been an issue in the past the shell I am using is GNU bash, version 3.2.51(1)-release (x86_64-apple-darwin13) Copyright (C) 2007 Free Software Foundation, Inc. any help you can offer would be much appreciated. Thank you, -Drew Lewis