New features
New global constants
Migrating from PHP 7.0.x to PHP 7.1.x
PHP Manual
New functions
PHP Core
sapi_windows_cp_get()
sapi_windows_cp_set()
sapi_windows_cp_conv()
sapi_windows_cp_is_utf8()
Closure
Closure::fromCallable()
CURL
curl_multi_errno()
curl_share_errno()
curl_share_strerror()
Session
session_create_id()
session_gc()
SPL
is_iterable()
PCNTL
pcntl_async_signals()
pcntl_signal_get_handler()
New features
New global constants
Migrating from PHP 7.0.x to PHP 7.1.x
PHP Manual