diff --git a/src/popupmnu.c b/src/popupmnu.c
index 7d2e137..eb4631a 100644
--- a/src/popupmnu.c
+++ b/src/popupmnu.c
@@ -466,7 +466,7 @@
 			set_option_value((char_u *)"bh", 0L,
 						 (char_u *)"wipe", OPT_LOCAL);
 			set_option_value((char_u *)"diff", 0L,
-						     (char_u *)"", OPT_LOCAL);
+							     NULL, OPT_LOCAL);
 		    }
 		}
 		if (res == OK)
diff --git a/src/quickfix.c b/src/quickfix.c
index 3b47132..1ae175b 100644
--- a/src/quickfix.c
+++ b/src/quickfix.c
@@ -2331,7 +2331,7 @@
 	    set_option_value((char_u *)"bt", 0L, (char_u *)"quickfix",
 								   OPT_LOCAL);
 	    set_option_value((char_u *)"bh", 0L, (char_u *)"wipe", OPT_LOCAL);
-	    set_option_value((char_u *)"diff", 0L, (char_u *)"", OPT_LOCAL);
+	    set_option_value((char_u *)"diff", 0L, NULL, OPT_LOCAL);
 	}
 
 	/* Only set the height when still in the same tab page and there is no
diff --git a/src/version.c b/src/version.c
index b68beb0..a69bbd2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -667,6 +667,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    16,
+/**/
     15,
 /**/
     14,