[Bug fortran/48298] [F03] User-Defined Derived-Type IO (DTIO)

[jvdelisle at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48298

--- Comment #21 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
Created attachment 39669
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39669&action=edit
Revised patch for review/testing

This revised patch speeds up execution on non DTIO internal units by saving and
reusing the unit structure, avoiding memory allocations.  I am still testing.
So far it passes regression tests.