diff --git a/src/vim.h b/src/vim.h
index 45cf8ca..7ef9b00 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -1255,6 +1255,7 @@
 #define WSP_BELOW	0x40	// put new window below/right
 #define WSP_ABOVE	0x80	// put new window above/left
 #define WSP_NEWLOC	0x100	// don't copy location list
+#define WSP_FORCE_ROOM	0x200	// ignore "not enough room" errors
 
 /*
  * arguments for gui_set_shellsize()