Backward Incompatible Changes
Although most existing PHP 5 code should work without changes, please take note of some backward incompatible changes:
Windows XP and 2003 support dropped
Support for Windows XP and 2003 has been dropped. Windows builds of PHP now require Windows Vista or newer.
Case insensitivity no longer locale specific
All case insensitive matching for function, class and constant names is now performed in a locale independent manner according to ASCII rules. This improves support for languages using the Latin alphabet with unusual collating rules, such as Turkish and Azeri.
This may cause issues for code that uses case insensitive matches for non-ASCII characters in multibyte character sets (including UTF-8), such as accented characters in many European languages. If you have a non-English, non-ASCII code base, then you will need to test that you are not inadvertently relying on this behaviour before deploying PHP 5.5 to production systems.
pack() and unpack() changes
Changes were made to pack() and unpack() to make them more compatible with Perl:
- pack() now supports the "Z" format code, which behaves identically to "a".
- unpack() now support the "Z" format code for NULL padded strings, and behaves as "a" did in previous versions: it will strip trailing NULL bytes.
- unpack() now keeps trailing NULL bytes when the "a" format code is used.
- unpack() now strips all trailing ASCII whitespace when the "A" format code is used.
Writing backward compatible code that uses the "a" format code with unpack() requires the use of version_compare(), due to the backward compatibility break.
For example:
<?php
// Old code:
$data = unpack('a5', $packed);
// New code:
if (version_compare(PHP_VERSION, '5.5.0-dev', '>=')) {
$data = unpack('Z5', $packed);
} else {
$data = unpack('a5', $packed);
}
?>
self, parent and static are now always case insensitive
Prior to PHP 5.5, cases existed where the self, parent, and static keywords were treated in a case sensitive fashion. These have now been resolved, and these keywords are always handled case insensitively: SELF::CONSTANT is now treated identically to self::CONSTANT.
PHP logo GUIDs removed
The GUIDs that previously resulted in PHP outputting various logos have been removed. This includes the removal of the functions to return those GUIDs. The removed functions are:
- php_logo_guid()
- php_egg_logo_guid()
- php_real_logo_guid()
- zend_logo_guid()
Internal execution changes
Extension authors should note that the zend_execute() function can no longer be overridden, and that numerous changes have been made to the execute_data struct and related function and method handling opcodes.
Most extension authors are unlikely to be affected, but those writing extensions that hook deeply into the Zend Engine should read the notes on these changes.
English translation
You have asked to visit this site in English. For now, only the interface is translated, but not all the content yet.If you want to help me in translations, your contribution is welcome. All you need to do is register on the site, and send me a message asking me to add you to the group of translators, which will give you the opportunity to translate the pages you want. A link at the bottom of each translated page indicates that you are the translator, and has a link to your profile.
Thank you in advance.
Document created the 30/01/2003, last modified the 26/10/2018
Source of the printed document:https://www.gaudry.be/en/php-rf-migration55.incompatible.html
The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.
References
These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.
