Description:
------------
When cURL is used with CURLOPT_SSL_VERIFYPEER set to TRUE or even without setting it (= default value is TRUE) there is a memory leakage with every call causing memory usage of php process to be constantly increasing.

memory_get_usage() reports still the same value so it must be core problem.

Keep test script running for more than 1 hour to see difference in memory usage (e.g. with top/htop etc.)

After running this script for 24 hours I got 50% of system memory to be used (cca 2GB)!

Test script:
---------------
  error_reporting((E_ALL));

  while (TRUE)
  {
    $url = "https://www.yahoo.com/";

    echo("Fetching $url ... \n");

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_NOBODY, TRUE);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, TRUE);
    curl_exec($ch);
    curl_close($ch);

    usleep(200000);
  }


Expected result:
----------------
No memory leakage even when script is running forever.

Actual result:
--------------
Memory usage is constantly increasing in time.