Repro for Phalcon issue 13354 using MySQL

_README.md

Before running this, you'll need to create the database:

$ mysql
...
mysql> create database issue13354;

issue13354.php

<?php

$di = new \Phalcon\Di\FactoryDefault();

$di->setShared('db', function () {
    return new \Phalcon\Db\Adapter\Pdo\Mysql([
        'host' => 'localhost',
        'username' => 'root',
        'password' => 'root',
        'dbname' => 'issue13354',
    ]);
});

$di['db']->execute(<<<SQL

DROP TABLE IF EXISTS `robot`;
DROP TABLE IF EXISTS `part`;

CREATE TABLE `robot` (
    id INT NOT NULL AUTO_INCREMENT,
    name VARCHAR(255), -- stop ORM throwing when no fields to save
    PRIMARY KEY (id)
);

CREATE TABLE `part` (
    id INT NOT NULL AUTO_INCREMENT,
    robot_id INT NOT NULL,
    PRIMARY KEY (id)
);
SQL);

class Robot extends \Phalcon\Mvc\Model
{
    public function initialize()
    {
        $this->hasMany('id', 'Part', 'robot_id', [
            'alias' => 'Parts'
        ]);
    }
}

class Part extends \Phalcon\Mvc\Model
{
    public function initialize()
    {
        $this->belongsTo('robot_id', 'Robot', 'id');
    }
}

// Repro
$robot = new Robot();
$part = new Part();

$robot->parts = [$part];
$part->robot = $robot;

echo "Going to save..\n";

$robot->save(); // <-- segfaults

echo "Finished executing\n";