Fix typo

From-SVN: r40426

gcc/alias.c

@@ -312,7 +312,7 @@ objects_must_conflict_p (t1, t2)
   /* If neither has a type specified, we don't know if they'll conflict
      because we may be using them to store objects of various types, for
      example the argument and local variables areas of inlined functions.  */
-  if (t1 == 0 && t1 == 0)
+  if (t1 == 0 && t2 == 0)
     return 0;
 
   /* If one or the other has readonly fields or is readonly,