Other Changes

Core changes


FFI::load() is now allowed during preloading when opcache.preload_user is the current system user. Previously, calling FFI::load() was not possible during preloading if the opcache.preload_user directive was set.


FPM CLI test now fails if the socket path is longer than supported by OS.


In the CLI and phpdbg SAPIs, preloading does not require the opcache.preload_user directive to be set anymore when running as root. In other SAPIs, this directive is required when running as root because preloading is done before the SAPI switches to an unprivileged user.


Blocking fread() on socket connection returns immediately if there are any buffered data instead of waiting for more data.

Memory stream no longer fails if seek offset is past the end. Instead the memory is increase on the next write and date between the old end and offset is filled with zero bytes in the same way how it works for files.

stat() access operations like file_exists() and similar will now use real path instead of the actual stream path. This is consistent with stream opening.

Changes in SAPI Modules


The STDOUT, STDERR and STDIN streams are no longer closed on resource destruction which is mostly when the CLI finishes. It is however still possible to explicitly close those streams using fclose() and similar.

Changed Functions


gc_status() has added the following 8 fields:

  • "running" => bool
  • "protected" => bool
  • "full" => bool
  • "buffer_size" => int
  • "application_time" => float: Total application time, in seconds (including collector_time)
  • "collector_time" => float: Time spent collecting cycles, in seconds (including destructor_time and free_time)
  • "destructor_time" => float: Time spent executing destructors during cycle collection, in seconds
  • "free_time" => float: Time spent freeing values during cycle collection, in seconds

class_alias() now supports creating an alias of an internal class.

Setting open_basedir at runtime using ini_set('open_basedir', ...); no longer accepts paths containing the parent directory (..). Previously, only paths starting with .. were disallowed. This could easily be circumvented by prepending ./ to the path.

User exception handlers now catch exceptions during shutdown.

The resultant HTML of highlight_string() and highlight_file() has changed. Whitespace between outer HTML tags is removed. Newlines and spaces are no longer converted to HTML entities. The whole HTML is now wrapped in a <pre> tag. The outer <span> tag has been merged with the <code> tag.


easter_date() now supports years from 1970 to 2,000,000,000 on 64-bit systems, previously it only supported years in the range from 1970 to 2037.


curl_getinfo() now supports two new constants: CURLINFO_CAPATH and CURLINFO_CAINFO. If option is null, the following two additional keys are present: "capath" and "cainfo".


Changed DOMCharacterData::appendData() tentative return type to true.

DOMDocument::loadHTML(), DOMDocument::loadHTMLFile(), and DOMDocument::loadXML() now have a tentative return type of bool. Previously, this was documented as having a return type of DOMDocument|bool, but, as of PHP 8.0.0, DOMDocument cannot be returned as it is no longer statically callable.


The signature of imagerotate() has changed. The $ignore_transparent parameter has been removed, as it was ignored since PHP 5.5.0.


datefmt_set_timezone() (and its alias IntlDateformatter::setTimeZone()) now returns true on success, previously null was returned.

IntlBreakiterator::setText() now returns false on failure, previously null was returned. It now returns true on success, previously null was returned.

IntlChar::enumCharNames() is now returning a boolean. Previously it returned null on success and false on failure.

IntlDateFormatter::__construct() throws an U_ILLEGAL_ARGUMENT_ERROR exception when an invalid locale had been set.


mb_strtolower() and mb_convert_case() implement conditional casing rules for the Greek letter sigma. For mb_convert_case(), conditional casing only applies to MB_CASE_LOWER and MB_CASE_TITLE modes, not to MB_CASE_LOWER_SIMPLE and MB_CASE_TITLE_SIMPLE.

mb_decode_mimeheader() interprets underscores in QPrint-encoded MIME encoded words as required by RFC 2047; they are converted to spaces. Underscores must be encoded as "=5F" in such MIME encoded words.

In rare cases, mb_encode_mimeheader() will transfer-encode its input string where it would pass it through as raw ASCII in PHP 8.2.

mb_encode_mimeheader() no longer drops NUL (zero) bytes when QPrint-encoding the input string. This previously caused strings in certain text encodings, especially UTF-16 and UTF-32, to be corrupted by mb_encode_mimeheader.

mb_detect_encoding()'s "non-strict" mode now behaves as described in the documentation. Previously, it would return false if the same byte (for example, the first byte) of the input string was invalid in all candidate encodings. More generally, it would eliminate candidate encodings from consideration when an invalid byte was seen, and if the same input byte eliminated all remaining encodings still under consideration, it would return false. On the other hand, if all candidate encodings but one were eliminated from consideration, it would return the last remaining one without regard for how many encoding errors might be encountered later in the string. This is different from the behavior described in the documentation, which says: "If strict is set to false, the closest matching encoding will be returned."


mysqli_fetch_object() now raises a ValueError instead of an Exception when the $constructor_args argument is non empty with the class not having constructor.

mysqli_poll() now raises a ValueError when neither the $read nor the $error arguments are passed.

mysqli_field_seek() and mysqli_result::field_seek() now specify the return type as true instead of bool.


odbc_autocommit() now accepts null for the $enable parameter. Passing null has the same behaviour as passing only 1 parameter, namely indicating if the autocommit feature is enabled or not.


pg_fetch_object() now raises a ValueError instead of an Exception when the $constructor_args argument is non empty with the class not having constructor.

pg_insert() now raises a ValueError instead of a E_WARNING when the table specified is invalid.

pg_insert() and pg_convert() raises a ValueError or a TypeError instead of a E_WARNING when the value/type of a field does not match properly with a PostgreSQL's type.

The $row parameter of pg_fetch_result(), pg_field_prtlen(), and pg_field_is_null() is now nullable.


Changed mt_srand() and srand() to not check the number of arguments to determine whether a random seed should be used. Passing null will generate a random seed, 0 will use zero as the seed. The functions are now consistent with Random\Engine\Mt19937::__construct().


Return type of ReflectionClass::getStaticProperties() is no longer nullable.


E_NOTICEs emitted by unserialize() have been promoted to E_WARNING.

unserialize() now emits a new E_WARNING if the input contains unconsumed bytes.

array_pad() is now only limited by the maximum number of elements an array can have. Before, it was only possible to add at most 1048576 elements at a time.

strtok() raises an E_WARNING in the case token is not provided when starting tokenization.

password_hash() will now chain the underlying Random\RandomException as the ValueError's $previous Exception when salt generation fails.

If using an array as the $command for proc_open(), it must now have at least one non empty element. Otherwise a ValueError is thrown.

proc_open() returns false if $command array is invalid command instead of resource object that produces warning later. This was already the case for Windows but it is now also the case if posix_spawn implementation is in use (most Linux, BSD and MacOS platforms). There are still some old platforms where this behavior is not changed as posix_spawn is not supported there.

array_sum() and array_product() now warn when values in the array cannot be converted to int/float. Previously arrays and objects where ignored whilst every other value was cast to int. Moreover, objects that define a numeric cast (e.g. GMP) are now casted instead of ignored.

The $decimal of number_format() now properly handles negative integers. Rounding with a negative value for $decimal means that $num is rounded to $decimals significant digits before the decimal point. Previously negative $decimals were silently ignored and the number got rounded to zero decimal places.

A new $before_needle argument has been added to strrchr(). It behaves like its counterpart in the strstr() or stristr() functions.

str_getcsv() and fgetcsv() now return an empty string instead of a string with a single null byte for the last field which only contains an unterminated enclosure.

Other Changes to Extensions


Using the increment/decrement operators (++/--) on values of type bool now emit warnings. This is because it currently has no effect, but will behave like $bool += 1 in the future.

Using the decrement operator (--) on values of type null now emit warnings. This is because it currently has no effect, but will behave like $null -= 1 in the future.

Internal objects that implement an _IS_NUMBER cast but not a do_operator handler that overrides addition and subtraction now can be incremented and decrement as if one would do $o += 1 or $o -= 1


The DOM lifetime mechanism has been reworked such that implicitly removed nodes can still be fetched. Previously this resulted in an exception.


The SQLite3 class now throws SQLite3Exception (extends Exception) instead of Exception.

The SQLite error code is now passed in the exception error code instead of being included in the error message.

Changes to INI File Handling

  • The assert.* INI settings have been deprecated. This comprises the following INI settings:

    If the value of the setting is equal to the default value, no deprecation notice is emitted. The zend.assertions INI setting should be used instead.

  • zend.max_allowed_stack_size is a new INI directive to set the maximum allowed stack size. Possible values are 0 (detect the process or thread maximum stack size), -1 (no limit), or a positive number of bytes. The default is 0. When it is not possible to detect the process or thread maximum stack size, a known system default is used. Setting this value too high has the same effect as disabling the stack size limit. Fibers use fiber.stack_size as maximum allowed stack size. An Error is thrown when the process call stack exceeds zend.max_allowed_stack_size-zend.reserved_stack_size bytes, to prevent stack-overflow-induced segmentation faults, with the goal of making debugging easier. The stack size increases during uncontrolled recursions involving internal functions or the magic methods __toString(), __clone(), __sleep(), __destruct(). This is not related to stack buffer overflows, and is not a security feature.

  • zend.reserved_stack_size is a new INI directive to set the reserved stack size, in bytes. This is subtracted from the max allowed stack size, as a buffer, when checking the stack size.



Looping over a DOMNodeList now uses caching. Therefore requesting items no longer takes quadratic time by default.

Getting text content from nodes now avoids an allocation, resulting in a performance gain.

DOMChildNode::remove() now runs in O(1) performance.


The file() flags error check is now about 7% faster.


RecursiveDirectoryIterator now performs less I/O when looping over a directory.

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