Migrating from PHP 7.1.x to PHP 7.2.x
PHP Manual

Other changes

Moving of utf8_encode() and utf8_decode()

The utf8_encode() and utf8_decode() functions have now been moved to the standard extension as string functions, whereas before the XML extension was required for them to be available.

Changes to mail() and mb_sendmail()

The $additional_headers parameter of mail() and mb_sendmail() now also accepts an array instead of a string.

LMDB support

The DBA extension now has support for LMDB.

Changes to the PHP build system

Changes to GD

Moving MCrypt to PECL

The MCrypt extension has now been moved out of the core to PECL. Given the mcrypt library has not seen any updates since 2007, its usage is highly discouraged. Instead, either the OpenSSL or Sodium extension should be used.


Migrating from PHP 7.1.x to PHP 7.2.x
PHP Manual