> - Core:
>    Added get_mangled_object_vars($object) function, which returns the mangled
>    object properties. It returns the same result as (array) $object, with the
>    exception that it ignores overloaded array casts, such as used by
>    ArrayObject.
>
> - OpenSSL:
>    Added openssl_x509_verify(mixed cert, mixed key) function that verifies the
>    signature of the certificate using a public key. A wrapper around the
>    OpenSSL's X509_verify() function.
>    See <php/php-src#3624>.
>
> - Pcntl:
>    Added bool pcntl_unshare(int flags) function which allows to dissociate
>    parts of the process execution context which are currently being shared with
>    other processes. Explicitly, it allows you to unshare the mount, IPC, UTS,
>    network, PID, user and cgroup namespaces.
>
> - Standard
>    * bool sapi_windows_set_ctrl_handler(callable handler, [, bool add = true]) -
>       set or remove a handler function upon receiving a CTRL event. The handler
>       function is expected have a signature "function handler(int $event)".
>    * bool sapi_windows_generate_ctrl_event(int type, int pid) - send a CTRL event
>       to another process.

Refs:
* https://github.com/php/php-src/blob/42cc58ff7b2fee1c17a00dc77a4873552ffb577f/UPGRADING#L348-L379