[mod4 (modulerc)]$ module purge
[mod4 (modulerc)]$ module load pgi/19.4
[mod4 (modulerc)]$ module load openmpi/4.0
[mod4 (modulerc)]$ module list
Currently Loaded Modulefiles:
 1) pgi/19.4   2) openmpi/4.0/pgi/19.4(default)
[mod4 (modulerc)]$ mpirun
mpirun (openmpi/4.0, pgi/19.4)
[mod4 (modulerc)]$ module unload openmpi
[mod4 (modulerc)]$ module switch --auto pgi intel/2019
[mod4 (modulerc)]$ module load openmpi/4.0
[mod4 (modulerc)]$ module list
Currently Loaded Modulefiles:
 1) intel/2019   2) openmpi/4.0/intel/2019(default)
[mod4 (modulerc)]$ mpirun
mpirun (openmpi/4.0, intel/2019)
[mod4 (modulerc)]$ module unload openmpi
[mod4 (modulerc)]$ module switch --auto intel gcc/9.1.0
[mod4 (modulerc)]$ module load openmpi/4.0
[mod4 (modulerc)]$ mpirun
mpirun (openmpi/4.0, gcc/9.1.0)
[mod4 (modulerc)]$ module unload openmpi
[mod4 (modulerc)]$ module switch --auto gcc gcc/8.2.0
[mod4 (modulerc)]$ module load openmpi/4.0

**** ERROR *****:
Compiler Mismatch
Package openmpi/4.0 does not appear to be built for currently
loaded compiler gcc/8.2.0.


Loading openmpi/4.0/gcc/9.1.0
  ERROR: Module evaluation aborted
[mod4 (modulerc)]$ module list
Currently Loaded Modulefiles:
 1) gcc/8.2.0
