[Patch, Fortran, committed] PR 60777: [F03] RECURSIVE function rejected in specification expression

[Janus Weil]

Hi all,

I just committed a close-to-obvious fix for PR60777 (ok'd by Steve in
the PR), see attachment:

https://gcc.gnu.org/viewcvs?rev=242009&root=gcc&view=rev

Cheers,
Janus

Index: gcc/fortran/expr.c
===================================================================
--- gcc/fortran/expr.c  (Revision 241993)
+++ gcc/fortran/expr.c  (Arbeitskopie)
@@ -2794,12 +2794,12 @@ external_spec_function (gfc_expr *e)
       return false;
     }
 
-  if (f->attr.recursive)
-    {
-      gfc_error ("Specification function %qs at %L cannot be RECURSIVE",
-                f->name, &e->where);
+  /* F08:7.1.11.6. */
+  if (f->attr.recursive
+      && !gfc_notify_std (GFC_STD_F2003,
+                         "Specification function '%s' "
+                         "at %L cannot be RECURSIVE",  f->name, &e->where))
       return false;
-    }
 
 function_allowed:
   return restricted_args (e->value.function.actual);

! { dg-do run }
!
! PR 60777: [F03] RECURSIVE function rejected in specification expression
!
! Contributed by Vladimir Fuka <vladimir.f...@gmail.com>

module recur
  implicit none
contains

  pure recursive function f(n) result(answer)
    integer, intent(in) :: n
    integer             :: answer
    if (n<2) then
      answer = 1
    else
      answer = f(n-1)*n
    end if
  end function

  pure function usef(n)
    integer,intent(in) :: n
    character(f(n))    :: usef
    usef = repeat('*',f(n))
  end function
end module

program testspecexpr
  use recur
  implicit none
  if (usef(1) /= '*')      call abort()
  if (usef(2) /= '**')     call abort()
  if (usef(3) /= '******') call abort()
end