The master branch breaks the ZEND_USER_OPCODE

Hi,

I use the following code the register a new ZEND_USER_OPCODE handler

    zend_uchar opcode = ZEND_VM_LAST_OPCODE + 1;

    while (1) {
            if (opcode == 255) {
                    return FAILURE;
            } else if (zend_get_user_opcode_handler(opcode) == NULL) {
                    break;
            }
            opcode++;
    }
    zend_set_user_opcode_handler(opcode, fiber_terminate_opcode_handler);

When I update to the latest master branch and run my php code, it raise a fatal error:

    Fatal error: Invalid opcode 199/8/8. in  on line 0

Could any one offer some help?

Thank you.

Haitao Lv