[Info-vax] GCC for VMS, was: Re: fortran compiler roadmap?

[Bob Koehler]

In article <kl4ag3$29k$1 at speranza.aioe.org>, glen herrmannsfeldt <gah at ugcs.caltech.edu> writes:
> 
> It seems to have taken a special fixup in the VMS linker to make it work.

   For passing CHARACTER to CHARACTER, no fix up is needed.  Lots of
   Fortran-77 compilers only support that.  To implement the
   Fortran-77 standard the compiler needs to pass both the size and
   location of CHARACTER arguments.

   But DEC supported passing character constants to integer, real, ...
   variables, as we had always done in Fortran-IV.  That took a linker
   fixup as in the calling routine the compiler would generate pass by
   descriptor, but in the receiving routine it would be expecting pass
   by reference.

   Different Fortran compilers have different ways of passing CHARACTER
   variable length between routines, but the RSX just didn't pass it. 
   So existing RSX code that passed character constants to integer, ...
   would keep running, but new code could not take advantage of the
   passed length wihtout explicitly passing it.