More Flexible Heredoc and Nowdoc Syntax
The closing marker for doc strings is no longer required to be followed by a semicolon or newline. Additionally the closing marker may be indented, in which case the indentation will be stripped from all lines in the doc string.

Array Destructuring supports Reference Assignments
Array destructuring now supports reference assignments using the syntax [&$a, [$b, &$c]] = $d. The same is also supported for list().

Instanceof Operator accepts Literals
instanceof now allows literals as the first operand, in which case the result is always FALSE.

CompileError Exception instead of some Compilation Errors
A new CompileError exception has been added, from which ParseError inherits. A small number of compilation errors will now throw a CompileError instead of generating a fatal error. Currently this only affects compilation errors that may be thrown by token_get_all() in TOKEN_PARSE mode, but more errors may be converted in the future.

Trailing Commas are allowed in Calls
Trailing commas in function and method calls are now allowed.

Argon2id Support
The –with-password-argon2[=dir] configure argument now provides support for both Argon2i and Argon2id hashes in the password_hash(), password_verify(), password_get_info(), and password_needs_rehash() functions. Passwords may be hashed and verified using the PASSWORD_ARGON2ID constant. Support for both Argon2i and Argon2id in the password_*() functions now requires PHP be linked against libargon2 reference library ≥ 20161029.