The CMPLIB (Compare Objects) tool compares objects from anywhere on the system to find differences in the object definition, or embedded modules or source version it was compiled from:
CMPOBJ OBJ(*ALL/PGM_NAME) TYPE(*ALL)
This will show all the objects that match your selection – then create a SHAH1 hash value based on
- object name
- object description
- source change date
- and embedded modules if an ILE object
For example, here is a real-world example where we want to see every occurrence of a program called pgm(ATLIMPRT) and compare the differences in any library system-wide:
CMPOBJ OBJ(*ALLUSR/ATLIMPRT) TYPE(*PGM)

We can see the different hash values on the right-hand column clearly showing which programs are identical and which have differences.