[Bug fortran/51995] [OOP] Polymorphic class fails at runtime

["jilfa12 at yahoo dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51995

--- Comment #9 from Prince <jilfa12 at yahoo dot com> 2012-01-25 13:32:50 UTC ---
Using five days old gcc version 4.7.0 20120120 (experimental) (GCC), 
the problem still persists.

I think the problem has not been fixed for the i686 architecture.
Do you know of any work-around for this? 
Ifort 12.1 runs the program successfully without memory leak.


________________________________
 From: burnus at gcc dot gnu.org <gcc-bugzilla@gcc.gnu.org>
To: jilfa12@yahoo.com 
Sent: Wednesday, January 25, 2012 2:47 PM
Subject: [Bug fortran/51995] [OOP] Polymorphic class fails at runtime

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51995

--- Comment #7 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-01-25
12:47:49 UTC ---
The problem seems to be the following:

One properly calls match_typebound_call, which sets "base" (alias "primary") to
the symtree of "db_connect" (which is of type BT_CLASS). Then it calls:

gfc_match_varspec (primary=0x16cf3d0, equiv_flag=0, sub_flag=true,
ppc_arg=true)

There, the problem is that one has:

  sym = sym->ts.u.derived;
  if (sym->f2k_derived)

But "sym" is only the class container. One needs
sym->components->ts.u.derived->f2k_derived.


One could simply do:

--- a/gcc/fortran/primary.c
+++ b/gcc/fortran/primary.c
@@ -1911 +1911,2 @@ gfc_match_varspec (gfc_expr *primary, int equiv_flag,
-  sym = sym->ts.u.derived;
+  sym = (sym->ts.type == BT_CLASS) ? CLASS_DATA (sym)->ts.u.derived
+                                  : sym->ts.u.derived;

But that will fail later with
internal compiler error: in gfc_conv_component_ref, at
fortran/trans-expr.c:1100