We return all integers that can be represented as such by PHP as
integers, and only those that exceed the possible range as strings.
On builds which represent integers with 64 bits, the range check is
unnecessary and might cause code checkers to complain, so we skip this
special casing via the preprocessor according to
<http://git.php.net/?p=php-src.git;a=commit;h=99d087e5>.
86e603a664