What potential pitfalls should be considered when defining arrays in PHP, especially when targeting compatibility with older versions like PHP 5.3?

When defining arrays in PHP for compatibility with older versions like PHP 5.3, it's important to avoid using short array syntax ([]) as it was introduced in PHP 5.4. Instead, use the array() function to define arrays. This ensures that the code will work across different PHP versions without any compatibility issues.

// Define array using array() function for compatibility with older PHP versions
$myArray = array('apple', 'banana', 'cherry');