diff --git a/mps/code/event.c b/mps/code/event.c
index d2b182d7377..5897031bcbe 100644
--- a/mps/code/event.c
+++ b/mps/code/event.c
@@ -494,11 +494,12 @@ Res EventDescribe(Event event, mps_lib_FILE *stream, Count depth)
 {
   UNUSED(event);
   UNUSED(stream);
+  UNUSED(depth);
   return ResUNIMPL;
 }
 
 
-Res EventWrite(Event event, mps_lib_FILE *stream, Count depth)
+Res EventWrite(Event event, mps_lib_FILE *stream)
 {
   UNUSED(event);
   UNUSED(stream);