php-src/UPGRADING

$Id$

PHP X.Y UPGRADE NOTES

1. Backward Incompatible Changes
2. New Features
3. Changes in SAPI modules
4. Deprecated Functionality
5. Changed Functions
6. New Functions
7. New Classes and Interfaces
8. Removed Extensions
9. Other Changes to Extensions
10. New Global Constants
11. Changes to INI File Handling
12. Windows Support
13. Other Changes


========================================
1. Backward Incompatible Changes
========================================

- Core
  . list() now always supports ArrayAccess and never supports strings.
    Previously both were accepted in some situations and not in others.
    (RFC: https://wiki.php.net/rfc/fix_list_behavior_inconsistency)
  . Bitwise shifts by negative numbers of bits are disallowed (throws E_WARNING
    and gives FALSE, like a division by zero).
  . Left bitwise shifts by a number of bits beyond the bit width of an integer
    will always result in 0, even on CPUs which wrap around.
  . Right bitwise shifts by a number of bits beyond the bit width of an integer
    will always result in 0 or -1 (depending on sign), even on CPUs which wrap
    around.
  . Removed ASP (<%) and script (<script language=php>) tags.
    (RFC: https://wiki.php.net/rfc/remove_alternative_php_tags)
  . call_user_method() and call_user_method_array() no longer exists.
  . PHP 7 doesn't keep original values of arguments passed to user functions,
    so func_get_arg() and func_get_args() will return current value of argument
    instead of the actually passed. The following code is going to be affected:
    function foo($x) { $x = 2; return func_get_arg(0);} var_dump(foo(1));
    It will now produce 2, not 1.
  . Function parameters with duplicate name are not allowed anymore. Definitions
    like “function foo($x,$x) {}” will lead to compile time error.
  . Indirect variable, property and method references are now interpreted with
    left-to-right semantics. See details in:
	https://wiki.php.net/rfc/uniform_variable_syntax#semantic_differences_in_existing_syntax 
  . The global keyword now only accepts simple variables. See details in:
    https://wiki.php.net/rfc/uniform_variable_syntax#global_keyword_takes_only_simple_variables
  . The addition of Unicode Codepoint Escape Syntax for double-quoted strings
    and heredocs means that \u{ followed by an invalid sequence will now error.
    However, \u without a following { is unaffected, so "\u202e" won't error and
    will work the same as before.
  . zend_function.common.num_args don't include the variadic argument anymore.
  . ob_start() no longer issues an E_ERROR, but instead an E_RECOVERABLE_ERROR in case an 
    output buffer is created in an output buffer handler.
  . Removed support for assigning the result of new by reference.
  . Removed support for scoped calls to non-static methods from an incompatible
    $this context. See details in https://wiki.php.net/rfc/incompat_ctx.
  . Removed support for #-style comments in ini files. Use ;-style comments
    instead.
  . Added zend_memnstr_ex, which is based on string matching sunday algo.
  . Added zend_memnrstr, zend_memnrstr_ex.
  . Added hybrid sorting algo zend_sort for better performance.
  . Added stable sorting algo zend_insert_sort.
  . Invalid octal literals in source code now produce compile errors, fixing
    PHPSadness #31. Previously, the invalid digits (and any following valid 
    digits) were simply ignored, such that 0781 became 7.
  . Removed dl() function on fpm-fcgi.
  . Removed support for hexadecimal numeric strings. This means that some
    operations like == will no longer specially interpret strings containing
    hexadecimal numbers. Furthermore is_numeric() will not consider hexadecimal
    strings to be numeric (use FILTER_VALIDATE_INT instead).
    (RFC: https://wiki.php.net/rfc/remove_hex_support_in_numeric_strings)
  . $HTTP_RAW_POST_DATA is no longer available. Use the php://input stream instead.

- Date:
  . Removed $is_dst parameter from mktime() and gmmktime().

- DBA
  . dba_delete() now returns false if the key was not found for the inifile
    handler, too.

- GMP
  . Requires libgmp version 4.2 or newer now.
  . gmp_setbit() and gmp_clrbit() now return FALSE for negative indices, making
    them consistent with other GMP functions.

- Session
  . session_start() accepts all INI settings as array. e.g. ['cache_limiter'=>'private']
    sets session.cache_limiter=private. It also supports 'read_and_close' which closes
    session data immediately after read data.
  . Save handler accepts validate_sid(), update_timestamp() which validates session
    ID existence, updates timestamp of session data. Compatibility of old user defined
    save handler is retained.
  . SessionUpdateTimestampHandlerInterface is added. validateSid(), updateTimestamp()
    is defined in the interface.
  . session.lazy_write(default=On) INI setting enables only write session data when
    session data is updated.

- PCRE:
  . Removed support for /e (PREG_REPLACE_EVAL) modifier. Use
    preg_reaplace_callback() instead.

- Standard:
  . Removed string category support in setlocale(). Use the LC_* constants
    instead.
  . Removed set_magic_quotes_runtime() and its alias magic_quotes_runtime().

- Stream:
  . Removed set_socket_blocking() in favor of its alias stream_set_blocking().

========================================
2. New Features
========================================

- Core
  . Added null coalesce operator (??).
    (RFC: https://wiki.php.net/rfc/isset_ternary)
  . Support for strings with length >= 2^31 bytes in 64 bit builds.
  . Closure::call() method added.
  . Added \u{xxxxxx} Unicode Codepoint Escape Syntax for double-quoted strings
    and heredocs.
  . define() now supports arrays as constant values, fixing an oversight where define() did not support arrays yet const syntax did.

========================================
3. Changes in SAPI modules
========================================

- FPM
  . Fixed bug #65933 (Cannot specify config lines longer than 1024 bytes).
  . Listen = port now listen on all addresses (IPv6 and IPv4-mapped).

========================================
4. Deprecated Functionality
========================================


========================================
5. Changed Functions
========================================

- parse_ini_file():
- parse_ini_string():
  . Added scanner mode INI_SCANNER_TYPED to yield typed .ini values.
- unserialize():
  . Added second parameter for unserialize function 
    (RFC: https://wiki.php.net/rfc/secure_unserialize) allowing to specify
    acceptable classes: 
    unserialize($foo, ["allowed_classes" => ["MyClass", "MyClass2"]);


========================================
6. New Functions
========================================
- GMP
  . Added gmp_random_seed().

- Standard
  . Added intdiv() function for integer division.

========================================
7. New Classes and Interfaces
========================================


========================================
8. Removed Extensions
========================================


========================================
9. Other Changes to Extensions
========================================


========================================
10. New Global Constants
========================================

- Core
  . PHP_INT_MIN added.

========================================
11. Changes to INI File Handling
========================================

- Core
  . Removed asp_tags ini directive. Trying to enable it will result in a fatal
    error.
  . Removed always_populate_raw_post_data ini directive.

========================================
12. Windows Support
========================================

- Core
  . Support for native 64 bit integers in 64 bit builds.
  . Support for large files in 64 bit builds.

========================================
13. Other Changes
========================================

- Core
  . Instead of being undefined and platform-dependent, NaN and Infinity will
    always be zero when casted to integer.
  . Calling a method on a non-object no longer raises a fatal error; see
    also: https://wiki.php.net/rfc/catchable-call-to-member-of-non-object.
  . Error messages for zend_parse_parameters, type hints and conversions now always say "integer" and "float" instead of "long" and "double".