diff --git a/arshal_test.go b/arshal_test.go
index f189e61..ce4f538 100644
--- a/arshal_test.go
+++ b/arshal_test.go
@@ -3736,7 +3736,10 @@ func TestMarshal(t *testing.T) {
 		want: `[null,{},null,{},null,null,{},{},null,{},null,null,{},"LAST"]`,
 		opts: []Options{
 			WithMarshalers(func() *Marshalers {
-				type P [2]int
+				type P struct {
+					D int
+					N int64
+				}
 				type PV struct {
 					P P
 					V any
@@ -7784,7 +7787,10 @@ func TestUnmarshal(t *testing.T) {
 		}),
 		opts: []Options{
 			WithUnmarshalers(func() *Unmarshalers {
-				type P [2]int
+				type P struct {
+					D int
+					N int64
+				}
 				type PV struct {
 					P P
 					V any
diff --git a/jsontext/decode.go b/jsontext/decode.go
index db39b8a..d1ef6ae 100644
--- a/jsontext/decode.go
+++ b/jsontext/decode.go
@@ -1037,7 +1037,7 @@ func (d *Decoder) StackDepth() int {
 // Each name and value in a JSON object is counted separately,
 // so the effective number of members would be half the length.
 // A complete JSON object must have an even length.
-func (d *Decoder) StackIndex(i int) (Kind, int) {
+func (d *Decoder) StackIndex(i int) (Kind, int64) {
 	// NOTE: Keep in sync with Encoder.StackIndex.
 	switch s := d.s.Tokens.index(i); {
 	case i > 0 && s.isObject():
diff --git a/jsontext/encode.go b/jsontext/encode.go
index b339d55..dbf64f0 100644
--- a/jsontext/encode.go
+++ b/jsontext/encode.go
@@ -896,7 +896,7 @@ func (e *Encoder) StackDepth() int {
 // Each name and value in a JSON object is counted separately,
 // so the effective number of members would be half the length.
 // A complete JSON object must have an even length.
-func (e *Encoder) StackIndex(i int) (Kind, int) {
+func (e *Encoder) StackIndex(i int) (Kind, int64) {
 	// NOTE: Keep in sync with Decoder.StackIndex.
 	switch s := e.s.Tokens.index(i); {
 	case i > 0 && s.isObject():
diff --git a/jsontext/state.go b/jsontext/state.go
index 1a8174c..52a703f 100644
--- a/jsontext/state.go
+++ b/jsontext/state.go
@@ -133,7 +133,7 @@ func (m *stateMachine) index(i int) *stateEntry {
 
 // DepthLength reports the current nested depth and
 // the length of the last JSON object or array.
-func (m stateMachine) DepthLength() (int, int) {
+func (m stateMachine) DepthLength() (int, int64) {
 	return m.Depth(), m.Last.Length()
 }
 
@@ -342,8 +342,8 @@ const (
 
 // Length reports the number of elements in the JSON object or array.
 // Each name and value in an object entry is treated as a separate element.
-func (e stateEntry) Length() int {
-	return int(e & stateCountMask)
+func (e stateEntry) Length() int64 {
+	return int64(e & stateCountMask)
 }
 
 // isObject reports whether this is a JSON object.
diff --git a/jsontext/state_test.go b/jsontext/state_test.go
index 6946c8b..943f6db 100644
--- a/jsontext/state_test.go
+++ b/jsontext/state_test.go
@@ -20,7 +20,7 @@ func TestStateMachine(t *testing.T) {
 	type operation any
 	type (
 		// stackLengths checks the results of stateEntry.length accessors.
-		stackLengths []int
+		stackLengths []int64
 
 		// appendTokens is sequence of token kinds to append where
 		// none of them are expected to fail.
@@ -156,12 +156,12 @@ func TestStateMachine(t *testing.T) {
 			for _, op := range ops {
 				switch op := op.(type) {
 				case stackLengths:
-					var got []int
+					var got []int64
 					for i := 0; i < state.Depth(); i++ {
 						e := state.index(i)
 						got = append(got, e.Length())
 					}
-					want := []int(op)
+					want := []int64(op)
 					if !reflect.DeepEqual(got, want) {
 						t.Fatalf("%s: stack lengths mismatch:\ngot  %v\nwant %v", sequence, got, want)
 					}