[Bug fortran/46408] [OOP] Segfault when running gfortran.dg/class_allocate_6.f03

["janus at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46408

janus at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|unassigned at gcc dot       |janus at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #8 from janus at gcc dot gnu.org 2011-01-02 19:23:55 UTC ---
(In reply to comment #7)
> 2) Forget about freeing the old value of 'dst' (which is fine as long as we
> only call _copy on allocation, where dst is undefined; this is currently the
> case).

This is definitely the proper thing to do: We only need _copy for ALLOCATE with
SOURCE. And the best thing is, it's really easily done:

Index: gcc/fortran/class.c
===================================================================
--- gcc/fortran/class.c    (revision 168379)
+++ gcc/fortran/class.c    (working copy)
@@ -548,7 +548,7 @@ gfc_find_derived_vtab (gfc_symbol *derived)
           copy->formal->next->sym = dst;
           /* Set up code.  */
           sub_ns->code = gfc_get_code ();
-          sub_ns->code->op = EXEC_ASSIGN;
+          sub_ns->code->op = EXEC_INIT_ASSIGN;
           sub_ns->code->expr1 = gfc_lval_expr_from_sym (dst);
           sub_ns->code->expr2 = gfc_lval_expr_from_sym (src);
           /* Set initializer.  */


It took me a long while to see this, but in the end it's completely trivial.
I'll commit after regtesting.