diff --git a/gcc/toplev.c b/gcc/toplev.c
index c3269f4edd0..f24767a845a 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -2389,8 +2389,12 @@ output_file_directive (asm_file, input_name)
   /* NA gets INPUT_NAME sans directory names.  */
   while (na > input_name)
     {
+      if (na[-1] == '/')
+	break;
+#ifdef DIR_SEPARATOR
       if (na[-1] == DIR_SEPARATOR)
 	break;
+#endif
       na--;
     }