Get the basename of MPI_LAUNCH more carefully.

configure.ac

@@ -183,7 +183,9 @@ AS_IF([test x"$mpi" != xfalse],
          [AC_MSG_WARN([check for MPI_LAUNCH disabled])],
          [AC_PATH_PROGS([MPI_LAUNCH], [poe mpirun mpiexec], [true])
        # set MP_HOSTFILE if we are using IBM PE
-       if test x"$(basename $ac_cv_path_MPI_LAUNCH)" == x"poe"; then
+       # $ac_cv_path_MPI_LAUNCH can be a command with arguments:
+       set dummy $ac_cv_path_MPI_LAUNCH
+       if test x"$(basename $[2])" == x"poe"; then
          # create tmp hostfile and export envVar MP_HOSTFILE
          # to enable compiler check for MPI compiler in case of IBM PE
          if test -z "${MP_HOSTFILE}"; then