Migrating from PHP 5.5.x to PHP 5.6.x

Most improvements in PHP 5.6.x have no impact on existing code. There are a few incompatibilities and new features that should be considered, and code should be tested before switching PHP versions in production environments.

Прогляньте також керівництво по міграції для версій PHP 5.0.x, 5.1.x, 5.2.x, 5.3.x, 5.4.x and 5.5.x.