My shop has a similar tool (that I had no part in writing, so I can't assist with the details). Basically, it "maps" fields (FOO is on segment BAR, position 51, length 5, format packed decimal). Note that this solution requires at least one of:
- A team of people technical enough to perform the mapping by hand
- The re-creation of a portion of the compiler
- A tool capable of extracting the necessary information from the compile listings
Think of it as reproducing the DB2 SYSCOLUMNS table.
"You have sat too long for any good you have been doing lately ... Depart, I say; and let us have done with you. In the name of God, go!" -- what I say to a junior programmer at least once a day