[Bug fortran/51338] [4.6/4.7 Regression] seg fault in gfc_dep_compare_expr with -O2

[bdavis at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51338

--- Comment #5 from Bud Davis <bdavis at gcc dot gnu.org> 2011-11-28 22:49:33 
UTC ---
Index: gcc/gcc/fortran/dependency.c
===================================================================
--- gcc/gcc/fortran/dependency.c    (revision 181789)
+++ gcc/gcc/fortran/dependency.c    (working copy)
@@ -245,6 +245,10 @@
   int i;
   gfc_expr *n1, *n2;

+  /* nothing to do here, move along */
+  if (e1 == NULL && e2 == NULL)
+     return 0;
+
   n1 = NULL;
   n2 = NULL;