diff --git a/internal/collections/syncmap.go b/internal/collections/syncmap.go
index 9a020bc23e..c191430535 100644
--- a/internal/collections/syncmap.go
+++ b/internal/collections/syncmap.go
@@ -13,7 +13,7 @@ type SyncMap[K comparable, V any] struct {
 
 func (s *SyncMap[K, V]) Load(key K) (value V, ok bool) {
 	val, ok := s.m.Load(key)
-	if !ok {
+	if !ok || val == nil {
 		return value, ok
 	}
 	return val.(V), true
@@ -25,6 +25,10 @@ func (s *SyncMap[K, V]) Store(key K, value V) {
 
 func (s *SyncMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool) {
 	actualAny, loaded := s.m.LoadOrStore(key, value)
+	if actualAny == nil {
+		return actual, loaded
+	}
+
 	return actualAny.(V), loaded
 }
 
@@ -38,7 +42,17 @@ func (s *SyncMap[K, V]) Clear() {
 
 func (s *SyncMap[K, V]) Range(f func(key K, value V) bool) {
 	s.m.Range(func(key, value any) bool {
-		return f(key.(K), value.(V))
+		var k K
+		if key != nil {
+			k = key.(K)
+		}
+
+		var v V
+		if value != nil {
+			v = value.(V)
+		}
+
+		return f(k, v)
 	})
 }
 
diff --git a/internal/collections/syncmap_test.go b/internal/collections/syncmap_test.go
new file mode 100644
index 0000000000..5fe7c578f4
--- /dev/null
+++ b/internal/collections/syncmap_test.go
@@ -0,0 +1,32 @@
+package collections_test
+
+import (
+	"testing"
+
+	"github.com/microsoft/typescript-go/internal/collections"
+	"gotest.tools/v3/assert"
+)
+
+func TestSyncMapWithNil(t *testing.T) {
+	t.Parallel()
+
+	var m collections.SyncMap[string, any]
+
+	got1, ok := m.Load("foo")
+	assert.Assert(t, !ok)
+	assert.Equal(t, got1, nil)
+
+	m.Store("foo", nil)
+
+	got2, ok := m.Load("foo")
+	assert.Assert(t, ok)
+	assert.Equal(t, got2, nil)
+
+	too, loaded := m.LoadOrStore("too", nil)
+	assert.Assert(t, !loaded)
+	assert.Equal(t, too, nil)
+
+	m.Range(func(k string, v any) bool {
+		return true
+	})
+}