[Bug fortran/77517] ICE in conv_intrinsic_move_alloc, at fortran/trans-intrinsic.c:9517

[anlauf at gmx dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77517

--- Comment #5 from Harald Anlauf <anlauf at gmx dot de> ---
Besides the lack of diagnosing the conflicting definitions,
I think there is a missing check in gfc_check_move_alloc().

The test case

program p
   class(*), allocatable :: a, b
   call move_alloc (a, b)
contains
   subroutine a
   end
end

hits near the end of the function

  /* CLASS arguments: Make sure the vtab of from is present.  */
  if (to->ts.type == BT_CLASS && !UNLIMITED_POLY (from))
    gfc_find_vtab (&from->ts);

However, for that case I get

 (gdb) print from->ts.type
$7 = BT_PROCEDURE

which should never happen, and is not expected.
To avoid an ICE, one might add a check just before this block, like:

  if (to->ts.type == BT_CLASS && from->ts.type != BT_CLASS)
    {
      gfc_error ("The FROM and TO arguments at %L are incompatible",
&to->where);
      return false;
    }