diff --git a/tools/trim/trim.go b/tools/trim/trim.go
index a9c3e03..25929c1 100644
--- a/tools/trim/trim.go
+++ b/tools/trim/trim.go
@@ -476,6 +476,6 @@
 	hidden bool
 }
 
-func iterKey(v cue.Iterator) key {
+func iterKey(v *cue.Iterator) key {
 	return key{v.Label(), v.IsHidden()}
 }