Description:
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When PHP is run with XDebug, set_time_limit (0) is not working.
After about a minute, the script stops alerting that maximum execution time is reached.
When I turn off XDebug, the program works as expected.


Reproduce code:
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//Code is too long an complex.

set_time_limit (0);
//do something that need a lot of time

Expected result:
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//program finishes successfully

Actual result:
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Maximum execution time of 30 seconds is reached.