Description:
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Since PHP 7.4, the ignoring of invalid hexadecimal characters is deprecated in "hexdec". However there's no changelog about this change on the function page on php.net and such the page still says that the function ignores invalid characters (that means there's no deprecation about this functionality!).

A changelog and notice/warning must be added to the manual page to indicate this deprecation.

If other functions were updated in the same regard as "hexdec", these pages must be updated as well.

Test script:
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echo hexdec('-2');

Expected result:
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2

Actual result:
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Deprecated: Invalid characters passed for attempted conversion, these have been ignored
2