Description:
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strtotime is very slow with very large values.



Reproduce code:
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php -r "echo strtotime('-50000000000 days');"

also, to clearly see this function has O(n) instead of O(1) complexity.

for x in {1..40}; do php -r "echo $x, \"\t\", pow ( 2, $x ), \"\t\", strtotime ( ( -1 * pow ( 2, $x ) ) . ' days' ), \"\n\";" 2> /dev/null; done;


Regardless of the fact you won't often work with dates 130 million years ago, this could be used to trigger a dos-like attack.

Expected result:
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Quick results

Actual result:
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veryyy slow results :)