Description:
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When you try to get the timestamp for day 0 of month 0 of the year 0, php returns 943916400 instead of false. It should return false because the input is clearly an invalid date and "0000-00-00" is not equal to "1999-11-30"

Test script:
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<?php
echo mktime(0,0,0,0,0,0);

Expected result:
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According to the documentation:
"mktime() returns the Unix timestamp of the arguments given. If the arguments are invalid, the function returns FALSE (before PHP 5.1 it returned -1)."

Therefore the output should be FALSE and not 943916400





Actual result:
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The actual result = 943916400