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mageekguy/gist:d71e784ef046e0342d52cc5d5b6d8bd2

Last active April 7, 2017 13:49
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About PHP_INT_MAX
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gistfile1.txt
# php --version
PHP 7.0.12 (cli) (built: Nov 3 2016 12:54:26) ( NTS )
Copyright (c) 1997-2016 The PHP Group
Zend Engine v3.0.0, Copyright (c) 1998-2016 Zend Technologies
# php -a
php > var_dump((PHP_INT_MAX + 1) > PHP_INT_MAX);
bool(false)
php > var_dump((PHP_INT_MAX + 1) < PHP_INT_MAX);
bool(false)
php > var_dump((PHP_INT_MAX + 1) == PHP_INT_MAX);
bool(true)
php > var_dump((PHP_INT_MAX + 1000) == PHP_INT_MAX);
bool(true)
@mageekguy
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For the record, (string) (PHP_INT_MAX + 1) > PHP_INT_MAX works like a charm.

@remicollet
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remicollet commented Apr 7, 2017 •
edited

Both are compared as float, so less significant digits are lost (63 bits for integer, 52 bits for float)

$ php -r 'var_dump(gmp_init(PHP_INT_MAX) + gmp_init(1) > gmp_init(PHP_INT_MAX));'
bool(true)

@remicollet
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IIRC there is an old proposal to switch to gmp by default on interger overflow.
BTW, huge performance issue.

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