Description:
------------
This code works as expected:

  $r = openssl_pkey_new();
  // passes
  assert(is_resource($r));
  openssl_pkey_free($r);
  // passes
  assert(!is_resource($r));



Test script:
---------------
This code works wrong:

  $r = openssl_pkey_new();
  openssl_pkey_export($r, $pem);
  openssl_pkey_free($r);
  $r = openssl_pkey_get_private($pem);
  // passes
  assert(is_resource($r));
  openssl_pkey_free($r);
  // assertion below must not pass but it does pass
  assert(is_resource($r));
  openssl_pkey_free($r);
  // passes
  assert(!is_resource($r));

Same wrong behaviour for openssl_pkey_get_public().

Expected result:
----------------
  // either that or openssl_pkey_get_public()
  $r = openssl_pkey_get_private($pem);
  // passes
  assert(is_resource($r));
  openssl_pkey_free($r);
  // passes (in reality DOES NOT)
  assert(is_resource($r));