Backward incompatible changes
Throw on passing too few function arguments
Previously, a warning would be emitted for invoking user-defined functions
with too few arguments. Now, this warning has been promoted to an Error
exception. This change only applies to user-defined functions, not internal
functions. For example:
Forbid dynamic calls to scope introspection functions
Dynamic calls for certain functions have been forbidden (in the form of
$func()
or array_map('extract', ...)
,
etc). These functions either inspect or modify another scope, and present
with them ambiguous and unreliable behavior. The functions are as follows:
-
assert - with a string as the first argument
-
compact
-
extract
-
func_get_args
-
func_get_arg
-
func_num_args
-
get_defined_vars
-
mb_parse_str - with one arg
-
parse_str - with one arg
Invalid class, interface, and trait names
The following names cannot be used to name classes, interfaces, or traits:
Numerical string conversions now respect scientific notation
Integer operations and conversions on numerical strings now respect
scientific notation. This also includes the (int)
cast
operation, and the following functions: intval (where
the base is 10), settype, decbin,
decoct, and dechex.
Fixes to mt_rand algorithm
mt_rand will now default to using the fixed version of
the Mersenne Twister algorithm. If deterministic output from
mt_rand was relied upon, then
MT_RAND_PHP
can be used as optional second parameter
to mt_srand to preserve the old (incorrect)
implementation.
rand aliased to mt_rand and
srand aliased to mt_srand
rand and srand have now been made
aliases to mt_rand and mt_srand,
respectively. This means that the output for the following functions have
changed: rand, shuffle,
str_shuffle, and array_rand.
Disallow the ASCII delete control character in identifiers
The ASCII delete control character (0x7F
) can no longer
be used in identifiers that are not quoted.
error_log
changes with syslog
value
If the error_log
ini setting is set to
syslog
, the PHP error levels are mapped to the syslog
error levels. This brings finer differentiation in the error logs in
contrary to the previous approach where all the errors are logged with the
notice level only.
Do not call destructors on incomplete objects
Destructors are now never called for objects that throw an exception during
the execution of their constructor. In previous versions this behavior
depended on whether the object was referenced outside the constructor (e.g.
by an exception backtrace).
call_user_func handling of reference arguments
call_user_func will now always generate a warning
upon calls to functions that expect references as arguments. Previously
this depended on whether the call was fully qualified.
Additionally, call_user_func and
call_user_func_array will no longer abort the function
call in this case. The "expected reference" warning will be emitted, but the
call will proceed as usual.
The empty index operator is not supported for strings anymore
Applying the empty index operator to a string (e.g. $str[] = $x
)
throws a fatal error instead of converting silently to array.
Assignment via string index access on an empty string
String modification by character on an empty string now works like for non-empty
strings, i.e. writing to an out of range offset pads the string with spaces,
where non-integer types are converted to integer, and only the first character of
the assigned string is used. Formerly, empty strings where silently treated like
an empty array.
Removed ini directives
The following ini directives have been removed:
-
session.entropy_file
-
session.entropy_length
-
session.hash_function
-
session.hash_bits_per_character
Array ordering when elements are automatically created during by reference
assignments has changed
The order of the elements in an array has changed when those elements have
been automatically created by referencing them in a by reference
assignment. For example:
Sort order of equal elements
The internal sorting algorithm has been improved, what may result in
different sort order of elements, which compare as equal, than before.
Note:
Don't rely on the order of elements which compare as equal; it might change
anytime.
Error message for E_RECOVERABLE errors
The error message for E_RECOVERABLE errors has been changed from "Catchable
fatal error" to "Recoverable fatal error".
$options parameter of unserialize()
The allowed_classes
element of the $options parameter of
unserialize is now strictly typed, i.e. if anything
other than an array or a bool is given,
unserialize() returns false
and issues an E_WARNING
.
DateTime constructor incorporates microseconds
DateTime and DateTimeImmutable
now properly incorporate microseconds when constructed from the current time,
either explicitly or with a relative string (e.g. "first day of next
month"
). This means that naive comparisons of two newly created
instances will now more likely return false
instead of true
:
Fatal errors to Error exceptions conversions
In the Date extension, invalid serialization data for
DateTime or DatePeriod classes,
or timezone initialization failure from serialized data, will now throw an
Error exception from the
__wakeup or __set_state
methods, instead of resulting in a fatal error.
In the DBA extension, data modification functions (such as
dba_insert) will now throw an
Error exception instead of triggering a catchable
fatal error if the key does not contain exactly two elements.
In the DOM extension, invalid schema or RelaxNG validation contexts will now
throw an Error exception instead of resulting in a
fatal error. Similarly, attempting to register a node class that does not
extend the appropriate base class, or attempting to read an invalid property
or write to a readonly property, will also now throw an
Error exception.
In the IMAP extension, email addresses longer than 16385 bytes will throw an
Error exception instead of resulting in a fatal error.
In the Intl extension, failing to call the parent constructor in a class
extending Collator before invoking the parent methods
will now throw an Error instead of resulting in a
recoverable fatal error. Also, cloning a
Transliterator object will now throw an
Error exception on failure to clone the internal
transliterator instead of resulting in a fatal error.
In the LDAP extension, providing an unknown modification type to
ldap_batch_modify will now throw an
Error exception instead of resulting in a fatal error.
In the mbstring extension, the mb_ereg and
mb_eregi functions will now throw a
ParseError exception if an invalid PHP expression is
provided and the 'e' option is used.
In the Mcrypt extension, the mcrypt_encrypt and
mcrypt_decrypt will now throw an
Error exception instead of resulting in a fatal error
if mcrypt cannot be initialized.
In the mysqli extension, attempting to read an invalid property or write to
a readonly property will now throw an Error exception
instead of resulting in a fatal error.
In the Reflection extension, failing to retrieve a reflection object or
retrieve an object property will now throw an Error
exception instead of resulting in a fatal error.
In the Session extension, custom session handlers that do not return strings
for session IDs will now throw an Error exception
instead of resulting in a fatal error when a function is called that must
generate a session ID.
In the SimpleXML extension, creating an unnamed or duplicate attribute will
now throw an Error exception instead of resulting in
a fatal error.
In the SPL extension, attempting to clone an
SplDirectory object will now throw an
Error exception instead of resulting in a fatal
error. Similarly, calling ArrayIterator::append when
iterating over an object will also now throw an Error
exception.
In the standard extension, the assert function, when
provided with a string argument as its first parameter, will now throw a
ParseError exception instead of resulting in a
catchable fatal error if the PHP code is invalid. Similarly, calling
forward_static_call outside of a class scope will now
throw an Error exception.
In the Tidy extension, creating a tidyNode manually
will now throw an Error exception instead of
resulting in a fatal error.
In the WDDX extension, a circular reference when serializing will now throw
an Error exception instead of resulting in a fatal
error.
In the XML-RPC extension, a circular reference when serializing will now
throw an instance of Error exception instead of
resulting in a fatal error.
In the Zip extension, the ZipArchive::addGlob
method will now throw an Error exception instead of
resulting in a fatal error if glob support is not available.
Lexically bound variables cannot reuse names
Variables bound to a closure via
the use
construct cannot use the same name as any
superglobals, $this, or any parameter. For
example, all of these function definition will result in a fatal error:
long2ip() parameter type change
long2ip now expects an int instead of a
string.
JSON encoding and decoding
The serialize_precision
ini setting now controls the
serialization precision when encoding floats.
Decoding an empty key now results in an empty property name, rather than
_empty_
as a property name.
When supplying the JSON_UNESCAPED_UNICODE
flag to
json_encode, the sequences U+2028 and U+2029 are now
escaped.
Changes to mb_ereg and mb_eregi
parameter semantics
The third parameter to the mb_ereg and
mb_eregi functions (regs
) will now be
set to an empty array if nothing was matched. Formerly, the parameter would
not have been modified.
Drop support for the sslv2 stream
The sslv2 stream has now been dropped in OpenSSL.
Forbid "return;" for typed returns already at compile-time
Return statements without argument in functions which declare a return type
now trigger E_COMPILE_ERROR
(unless the return type is
declared as void), even if the return statement would never be
reached.