How to use me:
1 Edit the SOURCES file to list all the header files you want to check
2 build -clean (or "iebuild -clean" if you are an IE weenie)
This step is important. build -c isn't good enough. Clean rebuilds
ensure that the tables are properly rebuilt.
3 build (or "iebuild")
This parses all the header files and builds a binary.
4 Run packchk.exe and save the output to a file ("before.csv")
5 Change your header files.
6 Repeat steps 2 and 3 to build a new exe.
7 Run packchk.exe and save the output to a new file ("after.csv")
8 Diff the two files. The results should be identical, except for
structures you deleted/added/modified.
If the diff reveals any other differences, then your structures are
not binary-compatible with the previous version of the header file.