[Bug fortran/71412] iso_c_bindings and optimization interaction bug

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71412

--- Comment #3 from kargl at gcc dot gnu.org ---
(In reply to relliott from comment #2)
> > I believe gfortran's behavior conforms to the standard.  F2003 states
> >
> >   When the execution of a procedure is terminated by execution
> >   of a RETURN or END statement, an allocatable variable that is
> >   a named local variable of the procedure retains its allocation
> >   and definition status if it has the SAVE attribute or is a
> >   function result variable or a subobject thereof; otherwise, it
> >   is deallocated.
> >
> > val is a local variable.  val does not have the SAVE attribute.
> 
> If that is the case, how should the desired result be achieved in a standard 
> conformant way?

Ahem, give val the SAVE attribute.

  integer(c_int), pointer, save :: val