diff --git a/support/mkdep b/support/mkdep
index fcad5c025..9cd911c79 100755
--- a/support/mkdep
+++ b/support/mkdep
@@ -1,6 +1,7 @@
 #!/bin/sh
 #
-# mkdep,v 1.3 1996/04/10 15:41:58 tardieu Exp
+# Compute build dependencies
+# $Id$
 #
 
 PREFIXLIST=
@@ -12,6 +13,9 @@ do
       PREFIXLIST="${PREFIXLIST}"`echo "$1" | sed 's/^-I//'`:
       shift
       ;;
+    -*)
+      shift
+      ;;
     *)
       break
       ;;