It is observed that a Copy of a load module under Endevor, via BSTCOPY, from PDSE to PDSE, can result in slight differences within the module, if a Byte compare using SuperCE is done.
It is advisable to do the comparison with PDSM36 (PDSMan) or AMBLIST (IBM); it will show that there is no actual difference in the executable code.
Referring to the SuperCE help - tutorial option 17.5 'Comparing load modules' - ISPF compares the entire module, not only the executable code. This would include IDR data which would have compile and linkedit information, as well as other undocumented information for a program object (a load module in a PDSE library).
BSTCOPY will use the Binder API to perform the operation of copying the program object, and this implies effectively a re-Binding of the program.
The best way to compare Load modules, is therefore not to use SuperCE, but instead use either AMBLIST or PDSM36( PDSMAN); these will only consider the executable code, instead of reading the module using BSAM.
Sample JCL forPDSM36:
//PDSM36 EXEC PGM=PDSM36,PARM='mbrname' //* //PDSMRPT DD SYSOUT=* //PDSMOLD DD DISP=SHR,DSN=library1 //PDSMNEW DD DISP=SHR,DSN=library2