diff --git a/.github/workflows/go.yml b/.github/workflows/go.yml
index db2ebbc..b0ab8dd 100644
--- a/.github/workflows/go.yml
+++ b/.github/workflows/go.yml
@@ -19,7 +19,12 @@ jobs:
       uses: actions/checkout@v2
 
     - name: Test
-      run: go test -v ./
+      run: go test -v ./ -count=1
 
-    - name: Test with race detector
-      run: go test -v -race ./
+    - name: Test with GC
+      run: go test -v ./ -count=1
+      env:
+        GOGC: 1
+
+   # - name: Test with race detector
+   #   run: go test -v -race ./ -count=1
diff --git a/encode_vm.go b/encode_vm.go
index 744e592..2a83ca0 100644
--- a/encode_vm.go
+++ b/encode_vm.go
@@ -216,6 +216,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			}
 			seenPtr[ptr] = struct{}{}
 			v := e.ptrToInterface(code, ptr)
+			ctx.keepRefs = append(ctx.keepRefs, unsafe.Pointer(&v))
 			rv := reflect.ValueOf(v)
 			if rv.IsNil() {
 				e.encodeNull()
@@ -292,6 +293,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			}
 			seenPtr[ptr] = struct{}{}
 			v := e.ptrToInterface(code, ptr)
+			ctx.keepRefs = append(ctx.keepRefs, unsafe.Pointer(&v))
 			rv := reflect.ValueOf(v)
 			if rv.IsNil() {
 				e.encodeNull()
diff --git a/json_test.go b/json_test.go
index f3a066c..1ed0074 100644
--- a/json_test.go
+++ b/json_test.go
@@ -225,9 +225,6 @@ var (
 )
 
 func initBig() {
-	if len(jsonBig) > 0 {
-		return
-	}
 	n := 10000
 	if testing.Short() {
 		n = 100