PHP 5.6.3 Doctrine Bug ->location:vendor/doctrine/orm/lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php

ClassMetadataInfo.php

    public function newInstance()
    {
        if ($this->_prototype === null) {
            if (PHP_VERSION_ID === 50429 || PHP_VERSION_ID === 50513 || PHP_VERSION_ID >= 50600) {
                $this->_prototype = $this->reflClass->newInstanceWithoutConstructor();
            } else {
                $this->_prototype = unserialize(sprintf('O:%d:"%s":0:{}', strlen($this->name), $this->name));
            }
        }

        return clone $this->_prototype;
    }