diff --git a/python/port/mod/turtle/modturtle.cpp b/python/port/mod/turtle/modturtle.cpp
index c2c8e78f8..44c78c0e4 100644
--- a/python/port/mod/turtle/modturtle.cpp
+++ b/python/port/mod/turtle/modturtle.cpp
@@ -8,7 +8,7 @@ static Turtle sTurtle;
 
 void modturtle_gc_collect() {
   // Mark the shared sTurtle object as a GC root
-  gc_collect_root((void **)&sTurtle, sizeof(Turtle));
+  gc_collect_root((void **)&sTurtle, sizeof(Turtle)/sizeof(void *));
 }
 
 void modturtle_view_did_disappear() {