New Global Constants
Other changes
Migrating from PHP 5.3.x to PHP 5.4.x
PHP Manual

## Changes to INI file handling

The following php.ini directives have been removed:

- register_globals and register_long_arrays
- magic_quotes_gpc, magic_quotes_runtime, and magic_quotes_sybase
- allow_call_time_pass_reference
- define_syslog_variables
- highlight.bg
- session.bug_compat_42 and session.bug_compat_warn
- y2k_compliance
- safe_mode, safe_mode_gid, safe_mode_include_dir, safe_mode_exec_dir, safe_mode_allowed_env_vars, and safe_mode_protected_env_vars

The following php.ini directives have been added:

- cli.pager and cli.prompt for CLI SAPI using readline in interactive mode.
- cli_server.color to enable the built-in development web server to use ANSI color coding in terminal output.
- max_input_vars - specifies how many GET/POST/COOKIE input variables may be accepted.
- zend.multibyte - to control the new multibyte support.
- zend.script_encoding - This value will be used unless a "declare(encoding=...)" directive appears at the top of the script.
- zend.signal_check - to check for replaced signal handlers on shutdown.
- session.upload_progress.enabled, session.upload_progress.cleanup, session.upload_progress.prefix, session.upload_progress.name, session.upload_progress.freq, session.upload_progress.min_freq
- enable_post_data_reading - When it's disabled, the POST data is not read (and processed)
- windows_show_crt_warning - This directive shows the Windows CRT warnings when enabled. These warnings were displayed by default until now.

The following php.ini. directives have been changed:

- session.entropy_file now defaults to /dev/random or /dev/urandom depending on what has been guessed at compile time.
- session.entropy_length now defaults to 32.