src/java.base/share/classes/java/lang/invoke/MethodHandle.java

8145371: ClassCastException thrown in LambdaFormEditor.getInCache
Reviewed-by: mhaupt

*** 1658,1674 ****
      /*non-public*/
      void updateForm(LambdaForm newForm) {
          assert(newForm.customized == null || newForm.customized == this);
          if (form == newForm)  return;
          newForm.prepare();  // as in MethodHandle.<init>
!         UNSAFE.putObject(this, FORM_OFFSET, newForm);
!         UNSAFE.fullFence();
      }
  
      /** Craft a LambdaForm customized for this particular MethodHandle */
      /*non-public*/
      void customize() {
          if (form.customized == null) {
              LambdaForm newForm = form.customize(this);
              updateForm(newForm);
          } else {
              assert(form.customized == this);
--- 1658,1674 ----
      /*non-public*/
      void updateForm(LambdaForm newForm) {
          assert(newForm.customized == null || newForm.customized == this);
          if (form == newForm)  return;
          newForm.prepare();  // as in MethodHandle.<init>
!         UNSAFE.putObjectVolatile(this, FORM_OFFSET, newForm);
      }
  
      /** Craft a LambdaForm customized for this particular MethodHandle */
      /*non-public*/
      void customize() {
+         final LambdaForm form = this.form;
          if (form.customized == null) {
              LambdaForm newForm = form.customize(this);
              updateForm(newForm);
          } else {
              assert(form.customized == this);