RFC: Adding debug information to LLVM to support Fortran

We use DW_TAG_string_type on OpenVMS I64 for Fortran CHARACTER*n,
Pascal's PACKED ARRAY OF CHAR, COBOL, etc. We'll want it as well. I
had sorta assumed it was already there?

For arrays with run-time bounds, we have them too in Pascal (they are
called "Schema Types" in the Extended Pascal standard). I'd prefer that
you pick a more generic name than "DIFortranSubrange" Again on OpenVMS
I64, we support bounds as subranges with literals, simple locations, or
thunk calls (as Pascal's computation of array bounds or size can get
complicated with uplevel referencing in the mix - we didn't want to have
to describe how to walk the static link in a location expression)

And Fortran's assumed shape arrays is exactly mapped to an OpenVMS
descriptor format (we have several) so we'll use these as well for
non-Fortran too.

Other than suggesting to make the names less Fortran specific (the folks
looking at adding PL/1 support would probably want to leverage all of
this, Ada too if somebody tackles that), I'm OK with the approach.


Hi John,

Thanks for the feedback. Glad that this might have broader usefulness.

We've obviously been focused on Fortran implementations, but we're not against generalizing.