Index: infrun.c
===================================================================
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.246
diff -u -p -r1.246 infrun.c
--- infrun.c	10 Sep 2007 18:49:26 -0000	1.246
+++ infrun.c	14 Sep 2007 21:28:04 -0000
@@ -2868,6 +2868,7 @@ insert_step_resume_breakpoint_at_frame (
 {
   struct symtab_and_line sr_sal;
 
+  gdb_assert (return_frame != NULL);
   init_sal (&sr_sal);		/* initialize to zeros */
 
   sr_sal.pc = gdbarch_addr_bits_remove