free-format support and handling/ignoring COBOL directives

In my humble opinion it would be best to just ignore any directive, that isn't supported, while adding a warning message. If those are used. A directive is always "first non-space is >>, followed by \s* then some directive words (only "reserved" there).

The likely most famous one is:

       >> SOURCE [FORMAT] [IS] FREE   [*> optional inline-comment]

Supporting free format would be good to allow testing with "more modern" code (some people are effectively writing ANSI85 + intrinsic functions in free-form reference-format).