The PVM package comes with a portable wrapper script for make called aimk, which takes care of setting all the right option for a given architecture. The program aimk assumes that the Makefile is named Makefile.aimk. A sample Makefile.aimk can be downloaded here: http://cs.boisestate.edu/~amit/teaching/430/lab/Makefile.aimk.sample
Edit the file Makefile.aimk to include a rule for your program and compile using the aimk command. Assuming that your rule in the Makefile.aimk is called myprog, you would use the following command.
aimk myprog
The executable will be placed in the directory ~/pvm3/bin/LINUXI386.