As you may know Magento 2.1.0 is out.
According to the release notes, only PHP 7.0.2 AND PHP 7.0.6 are supported
Why aren't PHP 7.0.3 / 7.0.4 / 7.0.5 supported ?
No official information but this Github issue gives a hint:
alankent commented on 8 Apr
Could you try 7.0.4? There are reports of something breaking with 7.0.5. Not sure who's fault, but 7.0.5 is behaving differently in a way that impacts Magento.
Vinai commented on 9 Apr
@alankent Same result in PHP 7.0.4
moleman commented 9 days ago
I had the same issue when running on php 7.0.5 but it works on php 7.0.6
Seems like they preferred to skip compatibility for the broken patch releases of PHP instead of working around them.
maksek commented 9 days ago
[...] we are not recommending using 7.0.5 due the bugs, check PHP version section - http://devdocs.magento.com/guides/v2.0/install-gde/system-requirements.html. Can you try to downgrade or upgrade PHP from 7.0.5 and check again?
From that doc page:
5.5.x, where x is 22 or greater
7.0.2–7.0.6 except for 7.0.5 (supported by Magento version 2.0.1 and later only)
There is a known PHP issue that affects our code compiler when using PHP 7.0.5. We recommend you not use PHP 7.0.5; instead, use PHP 7.0.2–7.0.4 or 7.0.6.
This does not mention problems with 7.0.3 or even 7.0.4 but it's likely that there were similar issues.
Magento 2.0.1 adds support for PHP 7.0.2, which provides dramatic performance improvements, drastically reduces memory consumption, and supports new PHP language features.