Aaron Jorbin writes to Make WordPress Core about WordPress and PHP7 (I run PHP7 and WordPress for quite some time on Saotn.org, and I think its a great step forward). For the last few months, WordPress Core has been getting ready for the upcoming release of PHP7. PHP7 is bringing a host of improvements to PHP. One of the most notably is substantial performance improvements. Benchmarks of WordPress using PHP7 are showing a 2-3x speed improvement compared to PHP5.6.
The first step towards support for PHP7 was to add PHP7 nightlies to the automated test matrix. For six months, WordPress has been testing every commit against PHP7. This helped us uncover a couple of now fixed issues.
For example, PHP7 deprecates PHP4 style constructors. Therefore, WordPress Core removed them and also added a deprecation notice to all themes and plugins using them to extend core classes. This is done to help ensure that as many themes and plugins as possible are ready for PHP7.
Next, WordPress Core fixed a small number of issues related to the Uniform Variable Syntax changes in PHP7. Plugin and Theme authors are strongly encouraged to familiarize themselves with this change and all other backwards incompatible changes.
PHP7 is currently targeted for release on November 12, 2015.
Read the full article on Make WordPress Core, WordPress and PHP7.