Merge branch 'PHP-5.6' into PHP-7.0

Author: bukka

ext/openssl/openssl.c

@@ -1318,6 +1318,9 @@ PHP_MSHUTDOWN_FUNCTION(openssl)
 	EVP_cleanup();
 
 #if OPENSSL_VERSION_NUMBER >= 0x00090805f
+	/* prevent accessing locking callback from unloaded extension */
+	CRYPTO_set_locking_callback(NULL);
+	/* free allocated error strings */
 	ERR_free_strings();
 #endif