diff --git a/src/p_spec.c b/src/p_spec.c
index a699cbc25..48c0f58b3 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -3042,7 +3042,7 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 			if (line->text)
 				LUAh_LinedefExecute(line, mo, callsec);
 			else
-				CONS_Alert(CONS_WARNING, "Linedef %d is missing the hook name of the Lua function to call! (This should be given in the front texture fields)\n", line-lines);
+				CONS_Alert(CONS_WARNING, "Linedef %s is missing the hook name of the Lua function to call! (This should be given in the front texture fields)\n", sizeu1(line-lines));
 #else
 			CONS_Alert(CONS_ERROR, "The map is trying to run a Lua script, but this exe was not compiled with Lua support!\n");
 #endif