问题
It's announced that PHP 7 supports "consistent 64-bit". What does this mean?
Does PHP 7 support Unicode similar to what was planned for PHP 6 (unicode.semantics directive, etc.)? If not, when will it support Unicode natively?
回答1:
Consistent 64-bit support
I think this relates to RFC: 64 bit platform improvements for string length and integer in zval.
It looks like the visible part of the iceberg is, as @cybersoft has mentioned already, that PHP 7 x64 on Windows now has 64-bit integers, whereas PHP 5.6 x64 still had 32-bit integers on this platform.
There is a RFC for a 64-bit integer type, but it's still work-in-progress since 2010, so it looks like we're still not getting a 64-bit integer on 32-bit platforms here.
Unicode support
AFAIK, there is no such thing as a Unicode implementation similar to what was planned for PHP 6. PHP will still deal with a binary string type for the foreseeable future, and the RFC for UString, which proposes to add a new type for Unicode strings, is still under discussion, so will not make it into PHP 7.0.
PHP however, still works quite well with UTF-8, as long as you use mb_*() functions instead of the basic string functions.
Note that PHP 7 also introduces a Unicode Codepoint Escape Syntax that helps dealing with UTF-8 strings.
回答2:
As I understand it, this means that the 64-bit version of PHP now has 64-bit integers. Previously, there were only 32-bit integers on x64 Windows.
来源：https://stackoverflow.com/questions/31066789/php-7-unicode-support-and-platform-independence