PHP, Bitwise operation, not negative -

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when trying code in php:

$result = 4 << 29; var_dump($result); // int(2147483648)

but in other languages, example in java or javascript -2147483648. why?

this depends on php version you're running. while ago there bug in 32-bit int math when comes overflows. has been solved in php 5.3.


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