-showme
       Do  not  invoke the underlying compiler.  Instead, show the command line that would be executed to
       compile the program.  NOTE: If a non-filename argument is passed on the command line, the  -showme
       option  will  not  display  any  additional  flags.  For example, both "mpicc --showme" and "mpicc
       --showme my_source.c" will show all the wrapper-supplied flags.  But "mpicc -showme -v" will  only
       show the underlying compiler name and "-v".