PHP 5.4 alpha1已经发布，让我们一起来看看PHP 5.4 alpha1具体有哪些方面的改进：
- autoconf 2.59+ is now supported (and required) for generating the
configure script with ./buildconf. Autoconf 2.60+ is desirable
otherwise the configure help order may be incorrect. (Rasmus, Chris Jones)
- Removed legacy features:
. break/continue $var syntax. (Dmitry)
. Safe mode and all related ini options. (Kalle)
. register_globals and register_long_arrays ini options. (Kalle)
. import_request_variables(). (Kalle)
. allow_call_time_pass_reference. (Pierrick)
. define_syslog_variables ini option and its associated function. (Kalle)
. highlight.bg ini option. (Kalle)
. Session bug compatibility mode (session.bug_compat42 and
session.bug_compat_warn ini options). (Kalle)
. session_is_registered(), session_register() and session_unregister()
functions. (Kalle)
. y2k_compliance ini option. (Kalle)
- Moved extensions to PECL: (Johannes)
. ext/sqlite.
- Changed $_SERVER['REQUEST_TIME'] to include microsecond precision. (Ilia)
- Changed default value of "default_charset" php.ini option from ISO-8859-1 to
UTF-8. (Rasmus)
- Changed array_combine() to return empty array instead of FALSE when both
parameter arrays are empty. FR #34857. (joel.perras@gmail.com)
- Changed third parameter of preg_match_all() to optional. FR #53238. (Adam)
- Changed silent casting of null/''/false into an Object when adding
a property into a warning. (Scott)
- <?= is now always available regardless of the short_tags setting (Rasmus)
- General improvements:
. Added multibyte support by default. Previously php had to be compiled
with --enable-zend-multibyte. Now it can be enabled or disabled through
zend.multibyte directive in php.ini. (Dmitry)
. Removed compile time dependency from ext/mbstring (Dmitry)
. Added support for Traits. (Stefan)
. Added closure $this support back. (Stas)
. Added array dereferencing support. (Felipe)
. Added indirect method call through array. FR #47160. (Felipe)
. Added support for object references in recursive serialize() calls.
FR #36424. (Mike)
. Added http_response_code() function. FR #52555. (Paul Dragoonis, Kalle)
. Added header_register_callback() which is invoked immediately
prior to the sending of headers and after default headers have
been added. (Scott)
. Added DTrace support. (David Soria Parra)
. Improved output layer, see README.NEW-OUTPUT-API for internals. (Mike)
. Improved unserialize() performance.
(galaxy dot mipt at gmail dot com, Kalle)
. Improved unix build system to allow building multiple PHP binary SAPIs and
one SAPI module the same time. FR #53271, FR #52410. (Jani)
. Added optional argument to debug_backtrace() and debug_print_backtrace()
to limit the amount of stack frames returned. (Sebastian, Patrick)
. Added stream metadata API support and stream_metadata() stream class
handler. (Stas)
- Improved Zend Engine memory usage: (Dmitry)
. Replaced zend_function.pass_rest_by_reference by
ZEND_ACC_PASS_REST_BY_REFERENCE in zend_function.fn_flags.
. Replaced zend_function.return_reference by ZEND_ACC_RETURN_REFERENCE
in zend_function.fn_flags.
. Removed zend_arg_info.required_num_args as it was only needed for internal
functions. Now the first arg_info for internal functions (which has special
meaning) is represented by zend_internal_function_info structure.
. Moved zend_op_array.size, size_var, size_literal, current_brk_cont,
backpatch_count into CG(context) as they are used only during compilation.
. Moved zend_op_array.start_op into EG(start_op) as it's used only for
'interactive' execution of single top-level op-array.
. Replaced zend_op_array.done_pass_two by ZEND_ACC_DONE_PASS_TWO in
zend_op_array.fn_flags.
. op_array.vars array is trimmed (reallocated) during pass_two.
. Replaced zend_class_entry.constants_updated by ZEND_ACC_CONSTANTS_UPDATED
in zend_class_entry.ce_flags.
. Reduced the size of zend_class_entry by sharing the same memory space
by different information for internal and user classes.
See zend_class_entry.info union.
. Reduced size of temp_variable.
- Changed the structure of op_array.opcodes. The constant values are moved from
opcode operands into a separate literal table. (Dmitry)
- Improved Zend Engine, performance tweaks and optimizations: (Dmitry)
. Inlined most probable code-paths for arithmetic operations directly into
executor.
. Eliminated unnecessary iterations during request startup/shutdown.
. Changed $GLOBALS into a JIT autoglobal, so it's initialized only if used.
(this may affect opcode caches!)
. Improved performance of @ (silence) operator.
. Simplified string offset reading. $str[1][0] is now a legal construct.
. Added caches to eliminate repeatable run-time bindings of functions,
classes, constants, methods and properties.
. Added concept of interned strings. All strings constants known at compile
time are allocated in a single copy and never changed.
. Added an optimization which saves memory and emalloc/efree calls for empty
HashTables. (Stas, Dmitry)
. ZEND_RECV now always has IS_CV as its result.
. ZEND_CATCH now has to be used only with constant class names.
. ZEND_FETCH_DIM_? may fetch array and dimension operands in different order.
. Simplified ZEND_FETCH_*_R operations. They can't be used with the
EXT_TYPE_UNUSED flag any more. This is a very rare and useless case.
ZEND_FREE might be required after them instead.
. Split ZEND_RETURN into two new instructions ZEND_RETURN and
ZEND_RETURN_BY_REF.
. Optimized access to global constants using values with pre-calculated
hash_values from the literals table.
. Optimized access to static properties using executor specialization.
A constant class name may be used as a direct operand of ZEND_FETCH_*
instruction without previous ZEND_FETCH_CLASS.
. zend_stack and zend_ptr_stack allocation is delayed until actual usage.
- Improved CLI SAPI: (Johannes)
. Added command line option --rz <name> which shows information of the
named Zend extension.
. Interactive readline shell improvements:
. Added "cli.pager" php.ini setting to set a pager for output.
. Added "cli.prompt" php.ini setting to configure the shell prompt.
. Added shortcut #inisetting=value to change ini settings at run-time.
. Changed shell not to terminate on fatal errors.
. Interactive shell works with shared readline extension. FR #53878.
- Improved FastCGI SAPI: (Dmitry)
. Added apache compatible functions: apache_child_terminate(),
getallheaders(), apache_request_headers() and apache_response_headers()
. Improved performance of FastCGI request parsing.
- Improved core functions:
. number_format() no longer truncates multibyte decimal points and thousand
separators to the first byte. FR #53457. (Adam)
. Added hex2bin() function. (Scott)
- Improved CURL extension:
. Added support for CURLOPT_MAX_RECV_SPEED_LARGE and
CURLOPT_MAX_SEND_SPEED_LARGE. FR #51815. (Pierrick)
- Improved Date extension:
. Added the + modifier to parseFromFormat to allow trailing text in the
string to parse without throwing an error. (Stas, Derick)
- Improved DBA extension:
. Added Tokyo Cabinet abstract DB support. (Michael Maclean)
. Added Berkeley DB 5 support. (Johannes, Chris Jones)
- Improved filesystem functions:
. scandir() now accepts SCANDIR_SORT_NONE as a possible sorting_order value.
FR #53407. (Adam)
- Improved HASH extension:
. Added Jenkins's one-at-a-time hash support. (Martin Jansen)
. Added FNV-1 hash support. (Michael Maclean)
. Made Adler32 algorithm faster. FR #53213. (zavasek at yandex dot ru)
- Improved intl extension:
. Added Spoofchecker, allows checking for visibly confusable characters and
other security issues. (Scott)
- Improved JSON extension:
. Added JsonSerializable interface. (Sara)
. Added JSON_BIGINT_AS_STRING, extended json_decode() sig with $options.
(Sara)
. Added support for JSON_NUMERIC_CHECK option in json_encode() that converts
numeric strings to integers. (Ilia)
. Added new json_encode() option JSON_PRETTY_PRINT. FR #44331. (Adam)
. Added new json_encode() option JSON_UNESCAPED_SLASHES. FR #49366. (Adam)
- Improved LDAP extension:
. Added paged results support. FR #42060. (ando@OpenLDAP.org,
iarenuno@eteo.mondragon.edu, jeanseb@au-fil-du.net, remy.saissy@gmail.com)
- Improved MySQL extensions:
. MySQL: Deprecated mysql_list_dbs(). FR #50667. (Andrey)
. mysqlnd: Added named pipes support. FR #48082. (Andrey)
. MySQLi: Added iterator support in MySQLi. mysqli_result implements
Traversable. (Andrey, Johannes)
. PDO_mysql: Removed support for linking with MySQL client libraries older
than 4.1. (Johannes)
- Improved OpenSSL extension:
. Added AES support. FR #48632. (yonas dot y at gmail dot com, Pierre)
. Added a "no_ticket" SSL context option to disable the SessionTicket TLS
extension. FR #53447. (Adam)
. Added no padding option to openssl_encrypt()/openssl_decrypt(). (Scott)
- Improved PDO DB-LIB: (Stanley)
. Added nextRowset support.
. Fixed bug #50755 (PDO DBLIB Fails with OOM).
- Improved PostgreSQL extension:
. Added support for "extra" parameter for PGNotify().
(r dot i dot k at free dot fr, Ilia)
- Improved Reflection extension: (Johannes)
. Added ReflectionExtension::isTemporary() and
ReflectionExtension::isPersistent() methods.
. Added ReflectionZendExtension class.
. Added ReflectionClass::isCloneable(). (Felipe)
- Improved Session extension:
. Added support for storing upload progress feedback in session data. (Arnaud)
. Changed session.entropy_file to default to /dev/urandom or /dev/arandom if
either is present at compile time. (Rasmus)
- Improved SPL extension:
. Added RegexIterator::getRegex() method. (Joshua Thijssen)
. Added SplObjectStorage::getHash() hook. (Etienne)
. Added SplFileInfo::getExtension(). FR #48767. (Peter Cowburn)
. Added CallbackFilterIterator and RecursiveCallbackFilterIterator. (Arnaud)
- Improved ZLIB extension:
. Re-implemented non-file related functionality. (Mike)
- Improved SNMP extension (Boris Lytochkin):
. Added OO API. FR #53594 (php-snmp rewrite).
. Sanitized return values of existing functions. Now it returns FALSE on
failure.
. Allow ~infinite OIDs in GET/GETNEXT/SET queries. Autochunk them to max_oids
upon request.
. Introducing unit tests for extension with ~full coverage.
. Fixed bugs
. #44193 (snmp v3 noAuthNoPriv doesn't work)
. #45893 (Snmp buffer limited to 2048 char)
. #46065 (snmp_set_quick_print() persists between requests)
. #51336 (snmprealwalk (snmp v1) does not handle end of OID tree correctly)
. #53862 (snmp_set_oid_output_format does not allow returning to default)
## UNSORTED ##
- Fixed PDO objects binary incompatibility. (Dmitry)
- Fixed bug #52211 (iconv() returns part of string on error). (Felipe)
下载地址：http://downloads.php.net/stas/php-5.4.0alpha1.tar.bz2