NAME
perl5380delta - what is new for perl v5.38.0
DESCRIPTION
This document describes differences between the 5.36.0 release and the 5.38.0 release.
Core Enhancements
New class
Feature
A new experimental syntax is now available for defining object classes, where per-instance data is stored in "field" variables that behave like lexicals.
This is described in more detail in perlclass. Notes on the internals of its implementation and other related details can be found in perlclassguts.
This remains a new and experimental feature, and is very much still under development. It will be the subject of much further addition, refinement and alteration in future releases. As it is experimental, it yields warnings in the experimental::class
category. These can be silenced by a no warnings
statement.
no
warnings
'experimental::class'
;
Unicode 15.0 is supported
See https://www.unicode.org/versions/Unicode15.0.0/ for details.
Deprecation warnings now have specific subcategories
All deprecation warnings now have their own specific deprecation category which can be disabled individually. You can see a list of all deprecated features in perldeprecation, and in warnings. The following list is from warnings:
+- deprecated ----+
| |
| +- deprecated::apostrophe_as_package_separator
| |
| +- deprecated::delimiter_will_be_paired
| |
| +- deprecated::dot_in_inc
| |
| +- deprecated::goto_construct
| |
| +- deprecated::smartmatch
| |
| +- deprecated::unicode_property_name
| |
| +- deprecated::version_downgrade
It is still possible to disable all deprecation warnings in a single statement with
no
warnings
'deprecated'
;
but now is possible to have a finer grained control. As has historically been the case these warnings are automatically enabled with
use
warnings;
%{^HOOK} API introduced
For various reasons it can be difficult to create subroutine wrappers for some of perl's keywords. Any keyword which has an undefined prototype simply cannot be wrapped with a subroutine, and some keywords which perl permits to be wrapped are in practice very tricky to wrap. For example require
is tricky to wrap, it is possible but doing so changes the stack depth, and the standard methods of exporting assume that they will be exporting to a package at certain stack depth up the stack, and the wrapper will thus change where functions are exported to unless implemented with a great deal of care. This can be very awkward to deal with.
Accordingly we have introduced a new hash called %{^HOOK}
which is intended to facilitate such cases. When a keyword supports any kind of special hook then the hook will live in this new hash. Hooks in this hash will be named after the function they are called by, followed by two underbars and then the phase they are executed in, currently either before or after the keyword is executed.
In this initial release we support two hooks require__before
and require__after
. These are provided to make it easier to perform tasks before and after a require statement.
See perlvar for more details.
PERL_RAND_SEED
Added a new environment variable PERL_RAND_SEED
which can be used to cause a perl program which uses rand
without using srand()
explicitly or which uses srand()
with no arguments to be repeatable. See perlrun. This feature can be disabled at compile time by passing
-Accflags=-DNO_PERL_RAND_SEED
to Configure during the build process.
Defined-or and logical-or assignment default expressions in signatures
The default expression for a subroutine signature parameter can now be assigned using the //=
or ||=
operators, to apply the defaults whenever the caller provided an undefined or false value (respectively), rather than simply when the parameter is missing entirely. For more detail see the documentation in perlsub.
@INC Hook Enhancements and $INC and INCDIR
The internals for @INC
hooks have been hardened to handle various edge cases and should no longer segfault or throw assert failures when hooks modify @INC
during a require operation. As part of this we now ensure that any given hook is executed at most once during a require call, and that any duplicate directories do not trigger additional directory probes.
To provide developers more control over dynamic module lookup, a new hook method INCDIR
is now supported. An object supporting this method may be injected into the @INC
array, and when it is encountered in the module search process it will be executed, just like how INC hooks are executed, and its return value used as a list of directories to search for the module. Returning an empty list acts as a no-op. Note that since any references returned by this hook will be stringified and used as strings, you may not return a hook to be executed later via this API.
When an @INC
hook (either INC
or INCDIR
) is called during require, the $INC
variable will be localized to be the value of the index of @INC
that the hook came from. If the hook wishes to override what the "next" index in @INC
should be it may update $INC
to be one less than the desired index (undef
is equivalent to -1
). This allows an @INC
hook to completely rewrite the @INC
array and have perl restart its directory probes from the beginning of @INC
.
Blessed CODE references in @INC
that do not support the INC
or INCDIR
methods will no longer trigger an exception, and instead will be treated the same as unblessed coderefs are, and executed as though they were an INC
hook.
Forbidden control flow out of defer
or finally
now detected at compile-time
It is forbidden to attempt to leave a defer
or finally
block by means of control flow such as return
or goto
. Previous versions of perl could only detect this when actually attempted at runtime.
This version of perl adds compile-time detection for many cases that can be statically determined. This may mean that code which compiled successfully on a previous version of perl is now reported as a compile-time error with this one. This only happens in cases where it would have been an error to actually execute the code anyway; the error simply happens at an earlier time.
Optimistic Eval in Patterns
The use of (?{ ... })
and (??{ ... })
in a pattern disables various optimisations globally in that pattern. This may or may not be desired by the programmer. This release adds the (*{ ... })
equivalent. The only difference is that it does not and will never disable any optimisations in the regex engine. This may make it more unstable in the sense that it may be called more or less times in the future, however the number of times it executes will truly match how the regex engine functions. For example, certain types of optimisation are disabled when (?{ ... })
is included in a pattern, so that patterns which are O(N) in normal use become O(N*N) with a (?{ ... })
pattern in them. Switching to (*{ ... })
means the pattern will stay O(N).
REG_INF has been raised from 65,536 to 2,147,483,647
Many regex quantifiers used to be limited to U16_MAX
in the past, but are now limited to I32_MAX
, thus it is now possible to write /(?:word){1000000}/
for example. Note that doing so may cause the regex engine to run longer and use more memory.
New API functions optimize_optree and finalize_optree
There are two new API functions for operating on optree fragments, ensuring you can invoke the required parts of the optree-generation process that might otherwise not get invoked (e.g. when creating a custom LOGOP). To get access to these functions, you first need to set a #define
to opt-in to using these functions.
#define PERL_USE_VOLATILE_API
These functions are closely tied to the internals of how the interpreter works, and could be altered or removed at any time if other internal changes make that necessary.
Some goto
s are now permitted in defer
and finally
blocks
Perl version 5.36.0 added defer
blocks and permitted the finally
keyword to also add similar behaviour to try
/catch
syntax. These did not permit any goto
expression within the body, as it could have caused control flow to jump out of the block. Now, some goto
expressions are allowed, if they have a constant target label, and that label is found within the block.
defer {
goto
LABEL;
"This does not execute\n"
;
LABEL:
"This does\n"
;
}
New regexp variable ${^LAST_SUCCESSFUL_PATTERN}
This allows access to the last succesful pattern that matched in the current scope. Many aspects of the regex engine refer to the "last successful pattern". The empty pattern reuses it, and all of the magic regex vars relate to it. This allows access to its pattern. The following code
if
(m/foo/ || m/bar/) {
s//PQR/;
}
can be rewritten as follows
if
(m/foo/ || m/bar/) {
s/${^LAST_SUCCESSFUL_PATTERN}/PQR/;
}
and it will do the exactly same thing.
Locale category LC_NAME now supported on participating platforms
On platforms that have the GNU extension LC_NAME
category, you may now use it as the category parameter to "setlocale" in POSIX to set and query its locale.
Incompatible Changes
readline() no longer clears the stream error and eof flags
readline()
, also spelled <>
, would clear the handle's error and eof flags after an error occurred on the stream.
In nearly all cases this clear is no longer done, so the error and eof flags now properly reflect the status of the stream after readline().
Since the error flag is no longer cleared calling close() on the stream may fail and if the stream was not explicitly closed, the implicit close of the stream may produce a warning.
This has resulted in two main types of problems in downstream CPAN modules, and these may also occur in your code:
If your code reads to end of file, and then rebinds the handle to a new file descriptor, previously since the eof flag wasn't set you could continue to read from the stream. You now need to clear the eof flag yourself with
$handle->clearerr()
to continue reading.If your code encounters an error on the stream while reading with readline() you will need to call
$handle->clearerr
to continue reading. The one case this occurred the underlying file descriptor was marked non-blocking, so the read() system call was failing withEAGAIN
, which resulted in the error flag being set on the stream.
The only case where error and eof flags continue to cleared on error is when reading from the child process for glob() in miniperl. This allows it to correctly report errors from the child process on close(). This is unlikely to be an issue during normal perl development.
INIT
blocks no longer run after an exit()
in BEGIN
INIT
blocks will no longer run after an exit()
performed inside of a BEGIN
. This means that the combination of the -v
option and the -c
option no longer executes a compile check as well as showing the perl version. The -v
option executes an exit(0) after printing the version information inside of a BEGIN
block, and the -c
check is implemented by using INIT
hooks, resulting in the -v
option taking precedence.
Syntax errors no longer produce "phantom error messages"
Generally perl will continue parsing the source code even after encountering a compile error. In many cases this is helpful, for instance with misspelled variable names it is helpful to show as many examples of the error as possible. But in the case of syntax errors continuing often produces bizarre error messages and may even cause segmentation faults during the compile process. In this release the compiler will halt at the first syntax error encountered. This means that any code expecting to see the specific error messages we used to produce will be broken. The error that is emitted will be one of the diagnostics that used to be produced, but in some cases some messages that used to be produced will no longer be displayed.
See "Changes to Existing Diagnostics" for more details.
utf8::upgrade()
Starting in this release, if the input string is undef
, it remains undef
. Previously it would be changed into a defined, zero-length string.
Changes to "thread-safe" locales
Perl 5.28 introduced "thread-safe" locales on systems that supported them, namely modern Windows, and systems supporting POSIX 2008 locale operations. These systems accomplish this by having per-thread locales, while continuing to support the older global locale operations for code that doesn't take the steps necessary to use the newer per-thread ones.
It turns out that some POSIX 2008 platforms have or have had buggy implementations, which forced perl to not use them. The ${^SAFE_LOCALES}
scalar variable contains 0 or 1 to indicate whether or not the current platform is considered by perl to have a working thread-safe implementation. Some implementations have been fixed already, but FreeBSD and Cygwin have been newly discovered to be sufficiently buggy that the thread-safe operations are no longer used by perl, starting in this release. Hence, ${^SAFE_LOCALES}
is now 0 for them. Older versions of perl can be configured to avoid these buggy implementations by adding the Configure option -DNO_POSIX_2008_LOCALE
.
And v5.38 fixes a bug in all previous perls that led to locales not being fully thread-safe. The first thread that finishes caused the main thread (named thread0
) to revert to the global locale in effect at startup, discarding whatever the thread's locale had been previously set to. If any other thread had switched to the global locale by calling switch_to_global_locale()
in XS code, those threads would all share the global locale, and thread0
would not be thread-safe.
Deprecations
Use of '
as a package name separator is deprecated
Using '
as package separator in a variable named in a double-quoted string has warned since 5.28. It is now deprecated in both string interpolation and non-interpolated contexts, and will be removed in Perl 5.42.
Switch and Smart Match operator
The "switch" feature and the smartmatch operator, ~~
, were introduced in v5.10. Their behavior was significantly changed in v5.10.1. When the "experiment" system was added in v5.18.0, switch and smartmatch were retroactively declared experimental. Over the years, proposals to fix or supplement the features have come and gone.
In v5.38.0, we are declaring the experiment a failure. Some future system may take the conceptual place of smartmatch, but it has not yet been designed or built.
These features will be entirely removed from perl in v5.42.0.
Performance Enhancements
Additional optree optimizations for common OP patterns. For example, multiple simple OPs replaced by a single streamlined OP, so as to be more efficient at runtime. [GH #19943], [GH #20063], [GH #20077].
Creating an anonymous sub no longer generates an
srefgen
op, the reference generation is now done in theanoncode
oranonconst
op, saving runtime. [GH #20290]
Modules and Pragmata
Updated Modules and Pragmata
Added the
is_tainted()
builtin function. [GH #19854]Added the
export_lexically()
builtin function as per PPC 0020. [GH #19895]Support for PPC 0018,
use feature "module_true";
has been added to the default feature bundle for v5.38 and later. It may also be used explicitly. When enabled inside of a module the module does not need to return true explicitly, and in fact the return will be forced to a simple true value regardless of what it originally was.Attribute::Handlers has been upgraded from version 1.02 to 1.03.
attributes has been upgraded from version 0.34 to 0.35.
autodie has been upgraded from version 2.34 to 2.36.
B has been upgraded from version 1.83 to 1.88.
B::Concise has been upgraded from version 1.006 to 1.007.
B::Deparse has been upgraded from version 1.64 to 1.74.
Benchmark has been upgraded from version 1.23 to 1.24.
bignum has been upgraded from version 0.65 to 0.66.
Carp has been upgraded from version 1.52 to 1.54.
Class::Struct has been upgraded from version 0.66 to 0.68.
Compress::Raw::Bzip2 has been upgraded from version 2.103 to 2.204_001.
Compress::Raw::Zlib has been upgraded from version 2.105 to 2.204_001.
Config::Perl::V has been upgraded from version 0.33 to 0.36.
CPAN has been upgraded from version 2.33 to 2.36.
Data::Dumper has been upgraded from version 2.184 to 2.188.
DB_File has been upgraded from version 1.857 to 1.858.
Devel::Peek has been upgraded from version 1.32 to 1.33.
Devel::PPPort has been upgraded from version 3.68 to 3.71.
Digest::MD5 has been upgraded from version 2.58 to 2.58_01.
Digest::SHA has been upgraded from version 6.02 to 6.04.
DynaLoader has been upgraded from version 1.52 to 1.54.
Encode has been upgraded from version 3.17 to 3.19.
encoding::warnings has been upgraded from version 0.13 to 0.14.
Env has been upgraded from version 1.05 to 1.06.
Errno has been upgraded from version 1.36 to 1.37.
experimental has been upgraded from version 0.028 to 0.031.
ExtUtils::CBuilder has been upgraded from version 0.280236 to 0.280238.
ExtUtils::Install has been upgraded from version 2.20 to 2.22.
ExtUtils::MakeMaker has been upgraded from version 7.64 to 7.70.
ExtUtils::Miniperl has been upgraded from version 1.11 to 1.13.
ExtUtils::ParseXS has been upgraded from version 3.45 to 3.51.
ExtUtils::PL2Bat has been upgraded from version 0.004 to 0.005.
ExtUtils::Typemaps has been upgraded from version 3.45 to 3.51.
feature has been upgraded from version 1.72 to 1.82.
File::Basename has been upgraded from version 2.85 to 2.86.
File::Copy has been upgraded from version 2.39 to 2.41.
File::Find has been upgraded from version 1.40 to 1.43.
File::Glob has been upgraded from version 1.37 to 1.40.
File::Spec has been upgraded from version 3.84 to 3.89.
File::stat has been upgraded from version 1.12 to 1.13.
FileHandle has been upgraded from version 2.03 to 2.05.
Filter::Util::Call has been upgraded from version 1.60 to 1.64.
GDBM_File has been upgraded from version 1.23 to 1.24.
Getopt::Long has been upgraded from version 2.52 to 2.54.
Hash::Util has been upgraded from version 0.28 to 0.30.
HTTP::Tiny has been upgraded from version 0.080 to 0.083.
I18N::Langinfo has been upgraded from version 0.21 to 0.22.
IO has been upgraded from version 1.50 to 1.52.
IO-Compress has been upgraded from version 2.106 to 2.204.
IO::Socket::IP has been upgraded from version 0.41 to 0.41_01.
On DragonflyBSD, detect setsockopt() not actually clearing
IPV6_V6ONLY
even when setsockopt() returns success. [cpan #148293]IO::Zlib has been upgraded from version 1.11 to 1.14.
JSON::PP has been upgraded from version 4.07 to 4.16.
libnet has been upgraded from version 3.14 to 3.15.
Locale::Maketext has been upgraded from version 1.31 to 1.33.
Math::BigInt has been upgraded from version 1.999830 to 1.999837.
Math::BigInt::FastCalc has been upgraded from version 0.5012 to 0.5013.
Math::BigRat has been upgraded from version 0.2621 to 0.2624.
Math::Complex has been upgraded from version 1.5902 to 1.62.
Memoize has been upgraded from version 1.03_01 to 1.16.
MIME::Base64 has been upgraded from version 3.16 to 3.16_01.
Module::CoreList has been upgraded from version 5.20220520 to 5.20230520.
mro has been upgraded from version 1.26 to 1.28.
NDBM_File has been upgraded from version 1.15 to 1.16.
Net::Ping has been upgraded from version 2.74 to 2.76.
ODBM_File has been upgraded from version 1.17 to 1.18.
Opcode has been upgraded from version 1.57 to 1.64.
overload has been upgraded from version 1.35 to 1.37.
parent has been upgraded from version 0.238 to 0.241.
PerlIO::via::QuotedPrint has been upgraded from version 0.09 to 0.10.
Pod::Checker has been upgraded from version 1.74 to 1.75.
Pod::Html has been upgraded from version 1.33 to 1.34.
Pod::Usage has been upgraded from version 2.01 to 2.03.
podlators has been upgraded from version 4.14 to 5.01.
POSIX has been upgraded from version 2.03 to 2.13.
re has been upgraded from version 0.43 to 0.44.
Safe has been upgraded from version 2.43 to 2.44.
Scalar::Util has been upgraded from version 1.62 to 1.63.
SDBM_File has been upgraded from version 1.15 to 1.17.
Socket has been upgraded from version 2.033 to 2.036.
Storable has been upgraded from version 3.26 to 3.32.
Sys::Hostname has been upgraded from version 1.24 to 1.25.
Term::Cap has been upgraded from version 1.17 to 1.18.
Test::Simple has been upgraded from version 1.302190 to 1.302194.
Text::Balanced has been upgraded from version 2.04 to 2.06.
threads has been upgraded from version 2.27 to 2.36.
threads::shared has been upgraded from version 1.64 to 1.68.
Tie::File has been upgraded from version 1.06 to 1.07.
Time::HiRes has been upgraded from version 1.9770 to 1.9775.
Time::Piece has been upgraded from version 1.3401 to 1.3401_01.
Unicode::Normalize has been upgraded from version 1.31 to 1.32.
UNIVERSAL has been upgraded from version 1.14 to 1.15.
User::grent has been upgraded from version 1.03 to 1.04.
User::pwent has been upgraded from version 1.01 to 1.02.
utf8 has been upgraded from version 1.24 to 1.25.
warnings has been upgraded from version 1.58 to 1.65.
XS::APItest has been upgraded from version 1.22 to 1.32.
XSLoader has been upgraded from version 0.31 to 0.32.
Documentation
New Documentation
perlclass
Describes the new class
feature.
perlclassguts
Describes the internals of the new class
feature.
Changes to Existing Documentation
We have attempted to update the documentation to reflect the changes listed in this document. If you find any we have missed, open an issue at https://github.com/Perl/perl5/issues.
Additionally, the following selected changes have been made:
perlapi
Documented
hv_ksplit
Documented
hv_name_set
hv_store
andhv_stores
documentation have been greatly improved.Documented
gv_autoload_pv
Documented
gv_autoload_pvn
Documented
gv_autoload_sv
Documented
gv_name_set
Documented
start_subparse
Documented
SV_CHECK_THINKFIRST_COW_DROP
Documented
SV_CHECK_THINKFIRST
Documented
SvPV_shrink_to_cur
Documented
save_aelem
Documented
save_aelem_flags
Documented
save_helem
Documented
save_helem_flags
perldeprecation
Added information about unscheduled deprecations and their categories.
Added category information for existing scheduled deprecations.
Added smartmatch and apostrophe as a package separator deprecation data.
perlintern
Documented
save_pushptr
Documented
save_scalar_at
Entries have been added to perlguts for the new
newAV_alloc_x
,newAV_alloc_xz
and*_simple
functions.References to the now-defunct PrePAN service have been removed from perlcommunity and perlmodstyle.
A section on symbol naming has been added to perlhacktips.
perlexperiment has been edited to properly reference the warning categories for the defer block modifier and extra paired delimiters for quote-like operators.
perlexperiment
Smartmatch has been moved from experimental status to deprecated status. Unfortunately the experiment did not work out.
perlfunc
Some wording improvements have been made for the
ucfirst
,push
,unshift
andbless
functions, as well as additional examples added.
perlhacktips
A new section, "Writing safer macros" in perlhacktips has been added to discuss pitfalls and solutions to using C macros in C and XS code.
A new section, "Choosing good symbol names" in perlhacktips, has been added to discuss unexpected gotchas with names.
perlop
Document the behavior of matching the empty pattern better and specify its relationship to the new
${^LAST_SUCCESSFUL_PATTERN}
properly.
perlvar
Added a section on "Scoping Rules of Regex Variables", and other wording improvements made throughout.
Added information on the new
%{^HOOK}
interface, and the newrequire__before
andrequire__after
hooks which it exposes.Correct information on the regex variables
${^PREMATCH}
,${^MATCH}
and${^POSTMATCH}
, all of which were incorrectly documented due to an oversight. Specifically they only work properly after a regex operation that used the /p modifier to enable them.Added information on the new regex variable
${^LAST_SUCCESSFUL_PATTERN}
, which represents the pattern of the last successful regex match in scope.
Diagnostics
The following additions or changes have been made to diagnostic output, including warnings and fatal error messages. For the complete list of diagnostic messages, see perldiag.
New Diagnostics
New Errors
A new syntax error has been added for the error that a
catch
block does not have its required variable declaration. See catch block requires a (VAR)Can't locate object method "INC", nor "INCDIR" nor string overload via package "%s" %s in @INC
-
(F) You are attempting to call
bless
with a package name that is a new-styleclass
. This is not necessary, as instances created by the constructor are already in the correct class. Instances cannot be created by other means, such asbless
. Cannot assign :param(%s) to field %s because that name is already in use
(F) An attempt was made to apply a parameter name to a field, when the name is already being used by another field in the same class, or one of its parent classes. This would cause a name clash so is not allowed.
Cannot create class %s as it already has a non-empty @ISA
(F) An attempt was made to create a class out of a package that already has an
@ISA
array, and the array is not empty. This is not permitted, as it would lead to a class with inconsistent inheritance.Cannot invoke a method of "%s" on an instance of "%s"
(F) You tried to directly call a
method
subroutine of one class by passing in a value that is an instance of a different class. This is not permitted, as the method would not have access to the correct instance fields.Cannot invoke method on a non-instance
(F) You tried to directly call a
method
subroutine of a class by passing in a value that is not an instance of that class. This is not permitted, as the method would not then have access to its instance fields.Cannot '%s' outside of a 'class'
(F) You attempted to use one of the keywords that only makes sense inside a
class
definition, at a location that is not inside such a class.Cannot reopen existing class "%s"
(F) You tried to begin a
class
definition for a class that already exists. A class may only have one definition block.Can't bless an object reference
(F) You attempted to call
bless
on a value that already refers to a real object instance.-
(F) On Cygwin, you called a path conversion function with an empty path. Only non-empty paths are legal.
Class already has a superclass, cannot add another
(F) You attempted to specify a second superclass for a
class
by using the:isa
attribute, when one is already specified. Unlike classes whose instances are created withbless
, classes created via theclass
keyword cannot have more than one superclass.Class attribute %s requires a value
(F) You specified an attribute for a class that would require a value to be passed in parentheses, but did not provide one. Remember that whitespace is not permitted between the attribute name and its value; you must write this as
class Example::Class :attr(VALUE) ...
Class :isa attribute requires a class but "%s" is not one
(F) When creating a subclass using the
class
:isa
attribute, the named superclass must also be a real class created using theclass
keyword.Field already has a parameter name, cannot add another
(F) A field may have at most one application of the
:param
attribute to assign a parameter name to it; once applied a second one is not allowed.Field attribute %s requires a value
(F) You specified an attribute for a field that would require a value to be passed in parentheses, but did not provide one. Remember that whitespace is not permitted between the attribute name and its value; you must write this as
field
$var
:attr(VALUE) ...
Field %s is not accessible outside a method
(F) An attempt was made to access a field variable of a class from code that does not appear inside the body of a
method
subroutine. This is not permitted, as only methods will have access to the fields of an instance.Field %s of "%s" is not accessible in a method of "%s"
(F) An attempt was made to access a field variable of a class, from a method of another class nested inside the one that actually defined it. This is not permitted, as only methods defined by a given class are permitted to access fields of that class.
Only scalar fields can take a :param attribute
(F) You tried to apply the
:param
attribute to an array or hash field. Currently this is not permitted.Required parameter '%s' is missing for %s constructor
(F) You called the constructor for a class that has a required named parameter, but did not pass that parameter at all.
Unexpected characters while parsing class :isa attribute: %s
(F) You tried to specify something other than a single class name with an optional trailing version number as the value for a
class
:isa
attribute. This confused the parser.Unrecognized class attribute %s
(F) You attempted to add a named attribute to a
class
definition, but perl does not recognise the name of the requested attribute.Unrecognized field attribute %s
(F) You attempted to add a named attribute to a
field
definition, but perl does not recognise the name of the requested attribute.Missing or undefined argument to %s via %{^HOOK}{require__before}
New Warnings
-
This is a shortened form of an already existing diagnostic, for use when there is no new locale being switched to. The previous diagnostic was misleading in such circumstances.
-
(S experimental::class) This warning is emitted if you use the
ADJUST
keyword ofuse feature 'class'
. This keyword is currently experimental and its behaviour may change in future releases of Perl. -
(S experimental::class) This warning is emitted if you use the
class
keyword ofuse feature 'class'
. This keyword is currently experimental and its behaviour may change in future releases of Perl. -
(W redefine) You redefined a method. To suppress this warning, say
{
no
warnings
'redefine'
;
*name
= method { ... };
}
Odd number of elements in hash field initialization
(W misc) You specified an odd number of elements to initialise a hash field of an object. Hashes are initialised from a list of key/value pairs so there must be a corresponding value to every key. The final missing value will be filled in with undef instead.
Old package separator "'" deprecated
(W deprecated, syntax) You used the old package separator "'" in a variable, subroutine or package name. Support for the old package separator will be removed in Perl 5.40.
-
(S experimental::class) This warning is emitted if you use the
field
keyword ofuse feature 'class'
. This keyword is currently experimental and its behaviour may change in future releases of Perl. -
(S experimental::class) This warning is emitted if you use the
method
keyword ofuse feature 'class'
. This keyword is currently experimental and its behaviour may change in future releases of Perl.
Changes to Existing Diagnostics
The compiler will now stop parsing on the first syntax error it encounters. Historically the compiler would attempt to "skip past" the error and continue parsing so that it could list multiple errors. For things like undeclared variables under strict this makes sense. For syntax errors however it has been found that continuing tends to result in a storm of unrelated or bizarre errors that mostly just obscure the true error. In extreme cases it can even lead to segfaults and other incorrect behavior.
Therefore we have reformed the continuation logic so that the parse will stop after the first seen syntax error. Semantic errors like undeclared variables will not stop the parse, so you may still see multiple errors when compiling code. However if there is a syntax error it will be the last error message reported by perl and all of the errors that you see will be something that actually needs to be fixed.
Error messages that output class or package names have been modified to output double quoted strings with various characters escaped so as to make the exact value clear to a reader. The exact rules on which characters are escaped may change over time but currently are that printable ASCII codepoints, with the exception of
"
and\
, and unicode word characters whose codepoint is over 255 are output raw, and any other symbols are escaped much as Data::Dumper might escape them, using\n
for newline and\"
for double quotes, etc. Codepoints in the range 128-255 are always escaped as they can cause trouble on unicode terminals when output raw.In older versions of perl the one liner
$ perl -le
'"thing\n"->foo()'
would output the following error message exactly as shown here, with text spread over multiple lines because the "\n" would be emitted as a raw newline character:
Can't locate object method
"foo"
via
package
"thing
" (perhaps you forgot to load "
thing
"?) at -e line 1.
As of this release we would output this instead (as one line):
Can't locate object method
"foo"
via
package
"thing\n"
(perhaps you forgot to load
"thing\n"
?) at -e line 1.
Notice the newline in the package name has been quoted and escaped, and thus the error message is a single line. The text is shown here wrapped to two lines only for readability.
When package or class names in errors are very large the middle excess portion will be elided from the message. As of this release error messages will show only up to the first 128 characters and the last 128 characters in a package or class name in error messages. For example
$ perl -le
'("Foo" x 1000)->new()'
will output the following as one line:
Can't locate object method
"new"
via
package
"FooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFooFo
"..."
oFooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFoo" (perhaps you forgot to load
"FooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFo"...
"oFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFoo
FooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFooFoo"?)
at -e line 1.
Notice the
"prefix"..."suffix"
form of the package name in this case. In previous versions of perl the complete string would have been shown making the error message over 6k long and there was no upper limit on the length of the error message at all. If you accidentally used a 1MB string as a class name then the error message would be over 2MB long. In this perl the upper limit should be around 2k when eliding and escaping are taken into account.Removed
Complex regular subexpression recursion limit (%d) exceeded
The regular expresion engine has not used recursion in some time. This warning no longer makes sense.
See [GH #19636].
Various warnings that used to produce parenthesized hints underneath the main warning message and after its "location data" were chanaged to put the hint inline with the main message. For instance:
Bareword found where operator expected at -e line 1, near
"foo bar"
(Do you need to predeclare foo?)
will now look like this but as one line:
Bareword found where operator expected (Do you need to predeclare
foo?) at -e line 1, near
"foo bar"
as a result such warnings will no longer trigger
$SIG{__WARN__}
twice, and the hint will be visible when fatal warnings is in effect.The error message that is produced when a
require
oruse
statement fails has been changed. It used to contain the words@INC contains:
, and it used to show the state of@INC
*after* the require had completed and failed. The error message has been changed to say@INC entries checked:
and to reflect the actual directories or hooks that were executed during the require statement. For example:perl -e'
push
@INC
,
sub
{
@INC
=()};
eval
"require Frobnitz"
or
die
$@'
Can't locate Frobnitz.pm in
@INC
(you may need to install the
Frobnitz module) (
@INC
contains:) at (
eval
1) line 1.
Will change to (with some output elided for clarity):
perl -e'
push
@INC
,
sub
{
@INC
=()};
eval
"require Frobnitz"
or
die
$@'
Can't locate Frobnitz.pm in
@INC
(you may need to install the
Frobnitz module) (
@INC
entries checked:
.../site_perl/5.38.0/x86_64-linux .../site_perl/5.38.0
.../5.38.0/x86_64-linux .../5.38.0 CODE(0x562745e684b8))
at (
eval
1) line 1.
thus showing the actual directories checked. Code that checks for
@INC contains:
in error messages should be hardened against any future wording changes between the@INC
and:
, for instance useqr/\@INC[ \w]+:/
instead of usingqr/\@INC contains:/
orqr/\@INC entries checked:/
in tests as this will ensure both forward and backward compatibility.Old package separator used in string
This diagnostic is now also part of the
deprecated
category.given is deprecated replaces
given is experimental
.when is deprecated replaces
when is experimental
.Smartmatch is deprecated replaces
Smartmatch is experimental
.
Configuration and Compilation
make -j6 minitest
could fail due to a build conflict in building$(MINIPERL_EXE)
between the main make process and a child process. [GH #19829]Properly populate osvers on Dragonfly BSD when the hostname isn't set.
Fix typos for C99 macro name
PRIX64
.Remove ancient and broken GCC for VMS support
Remove vestigial reference to
/VAXC
qualifierRemove sharedperl option on VMS
VMS now has mkostemp
Configure
now properly handles quoted elements outputted by gcc. [GH #20606]Configure
probed for the return type of malloc() and free() by testing whether declarations for those functions produced a function type mismatch with the implementation. On Solaris, with a C++ compiler, this check always failed, since Solaris instead imports malloc() and free() fromstd::
withusing
for C++ builds. Since the return types of malloc() and free() are well defined by the C standard, skip probing for them.Configure
command-line arguments and hints can still override these type in the unlikely case that is needed. [GH #20806]
Testing
Tests were added and changed to reflect the other additions and changes in this release. Furthermore, these significant changes were made:
Unicode normalization tests have been added.
t/test.pl: Add ability to cancel an watchdog timer
Platform Support
Discontinued Platforms
- Ultrix
-
Support code for DEC Ultrix has been removed. Ultrix was the native Unix-like operating system for various Digital Equipment Corporation machines. Its final release was in 1995.
Platform-Specific Notes
- DragonflyBSD
-
Skip tests to workaround an apparent bug in
setproctitle()
. [GH #19894] - FreeBSD
-
FreeBSD no longer uses thread-safe locale operations, to avoid a bug in FreeBSD
Replace the first part of archname with
uname -p
[GH #19791] - Solaris
-
Avoid some compiler and compilation issues on NetBSD/Solaris from regexec.c and regcomp.c.
- Synology
-
Update Synology Readme for DSM 7.
- Windows
-
Fix win32 memory alignment needed for gcc-12 from vmem.h.
utimes() on Win32 would print a message to stderr if it failed to convert a supplied
time_t
to aFILETIME
. [GH #19668]In some cases, timestamps returned by stat() and lstat() failed to take daylight saving time into account. [GH #20018] [GH #20061]
stat() now works on
AF_UNIX
socket files. [GH #20204]readlink() now returns the
PrintName
from a symbolic link reparse point instead of theSubstituteName
, which should make it better match the name the link was created with. [GH #20271]lstat() on Windows now returns the length of the link target as the size of the file, as it does on POSIX systems. [GH #20476]
symlink() on Windows now replaces any
/
in the target with\
, since Windows does not recognise/
in symbolic links. The reverse translation is not done by readlink(). [GH #20506]symlink() where the target was an absolute path to a directory was incorrectly created as a file symbolic link. [GH #20533]
POSIX::dup2
no longer creates broken sockets. [GH #20920]Closing a busy pipe could cause Perl to hang. [GH #19963]
Internal Changes
Removed many deprecated C functions.
These have been deprecated for a long time. See https://github.com/perl/perl5/commit/7008caa915ad99e650acf2aea40612b5e48b7ba2 for a full list.
get_op_descs
,get_op_names
,get_opargs
,get_no_modify
andget_ppaddr
have been marked deprecated.hv_free_ent
has been marked as internal API.save_pushptr
,save_pushptrptr
, andsave_pushi32ptr
have been marked as internal API.New bool related functions and macros have been added to complement the new bool type introduced in 5.36:
The functions are:
newSVbool(const bool bool_val)
newSV_true()
newSV_false()
sv_set_true(SV *sv)
sv_set_false(SV *sv)
sv_set_bool(SV *sv, const bool bool_val)
The macros are:
Perl is no longer manipulating the
environ
array directly. The variablePL_use_safe_putenv
has been removed andPERL_USE_SAFE_PUTENV
is always defined. This means XS modules can now callsetenv
andputenv
without causing segfaults. [perl #19399]Internal C API functions are now hidden with
__attribute__((hidden))
on the platforms that support it. This means they are no longer callable from XS modules on those platforms.It should be noted that those functions have always been hidden on Windows. This change merely brings that to the other platforms. [perl #19655]
New formatting symbols were added for printing values declared as
U32
orI32
:These are used in the same way already existing similar symbols, such as
IVdf
, are used. See "I/O Formats" in perlapi.new 'HvHasAUX' macro
regexec.c: Add some branch predictions reorder conds
locale: Change macro name to be C conformant
Rename the
PADNAMEt_*
constants toPADNAMEf_*
Changes all the API macros that retrieve a PV into a call to an inline function so as to evaluate the parameter just once.
regexec.c: multiple code refactor to make the code more readable
perl.h: Change macro name to be C conformant (remove leading _ from NOT_IN_NUMERIC macros)
regcomp.h: add new
BITMAP_BIT
macro in addition to the existingBITMAP_BYTE
andBITMAP_TEST
ones.Create new regnode type ANYOFH. populate_ANYOF_from_invlist was renamed to populate_bitmap_from_invlist
regex: Refactor bitmap vs non-bitmap of qr/[]/
regcomp.c: add new functions to convert from an inversion list to a bitmap (and vice versa)
populate_bitmap_from_invlist
andpopulate_invlist_from_bitmap
.Add
newAVav()
to create an AV from an existing AV. AddnewAVhv()
to create an AV using keys and values from an existing HV.Fix definition of
Perl_atof
.Fix undefined behavior with overflow related
OPTIMIZE_INFTY
and delta in regcomp.c.Fix regnode pointer alignment issue in regcomp.h.
The
CVf_METHOD
CV flag and associatedCvMETHOD
macro has been renamed toCVf_NOWARN_AMBIGUOUS
andCvNOWARN_AMBIGUOUS
. This closer reflects its actual behaviour (it suppresses a warning that would otherwise be generated about ambiguous names), in order to be less confusing withCvIsMETHOD
, which indicates that a CV is amethod
subroutine relating to theclass
feature.The
OPf_SPECIAL
flag is no longer set on theOP_ENTERSUB
op constructed to call theVERSION
,import
andunimport
methods as part of ause
statement and attribute application, nor when assigning to an:lvalue
subroutine.A new CV flag
CVf_REFCOUNTED_ANYSV
has been added, which indicates that the CV is an XSUB and stores an SV pointer in theCvXSUBANY.any_sv
union field. Perl core operations such as cloning or destroying the CV will maintain the reference count of the pointed-to SV, destroying it when required.A new API function "
Perl_localeconv
" in perlapi is added. This is the same asPOSIX::localeconv
(returning a hash of thelocaleconv()
fields), but directly callable from XS code.A new API function, "
Perl_langinfo8
" in perlapi is added. This is the same as plain "Perl_langinfo
" in perlapi, but with an extra parameter that allows the caller to simply and reliably know if the returned string is UTF-8.We have introduced a limit on the number of nested
eval EXPR
/BEGIN
blocks andrequire
/BEGIN
(and thususe
statements as well) to prevent C stack overflows. This variable can also be used to forbidBEGIN
blocks from executing duringeval EXPR
compilation. The limit defaults to1000
but can be overridden by setting the${^MAX_NESTED_EVAL_BEGIN_BLOCKS}
variable. The default itself can be changed at compile time with-Accflags=
'-DPERL_MAX_NESTED_EVAL_BEGIN_BLOCKS_DEFAULT=12345'
Note that this value relates to the size of your C stack and if you choose an inappropriately large value Perl may segfault, be conservative about what you choose.
A new magic type
PERL_MAGIC_extvalue
has been added. This is available for use likePERL_MAGIC_ext
, but is a value magic: upon localization the new value will not be magical.The
SSNEW()
,SSNEWt()
,SSNEWa()
andSSNEWat()
APIs now return aSSize_t
value. TheSSPTR()
andSSPTRt()
macros now expect aSSize_t
parameter, and enforce that on debugging builds. [GH #20411]Filenames in cops are now refcounted under threads. Under threads we were copying the filenames into each opcode. This is because in theory opcodes created in one thread can be destroyed in another. The change adds a new struct/type
RCPV
, which is a refcounted string using shared memory. This is implemented in such a way that code that previously used a char * can continue to do so, as the refcounting data is located a specific offset before the char * pointer itself.Added
HvNAMEf
andHvNAMEf_QUOTEDPREFIX
special formats. They take anHV *
as an argument and useHvNAME()
and related macros to determine the string, its length, and whether it is utf8.The underlying
Perl_dowantarray
function implementing the long-deprecatedGIMME
macro has been marked as deprecated, so that use of the macro emits a compile-time warning.GIMME
has been documented as deprecated in favour ofGIMME_V
since Perl v5.6.0, but had not previously issued a warning.The API function "utf8_length" in perlapi is now more efficient.
Added
SAVERCPV()
andSAVEFREERCPV()
for better support for working withRCPV
(reference counted string/pointer value) structures which currently are used in opcodes to share filename and warning bit data in a memory efficient manner.Added
MORTALSVFUNC_SV()
andMORTALDESTRUCTOR_SV()
macros, which make it possible to create a destructor which is fired at the end of the current statement. This uses thePERL_MAGIC_destruct
magic to use "free" magic to trigger an action when a variable is freed. The action can be specified as a C function or as a Perl code reference.Added the
%{^HOOK}
api and relatedPERL_MAGIC_hook
andPERL_MAGIC_hookelem
for providing ways to hook selected perl functions which for one reason or another are problematic to wrap with a customized subroutine.Added support for
${^HOOK}{require__before}
which can be used to rewrite the filename thatrequire
will try to load, and also to blockrequire
from loading a specific module, even via fully qualified filename. The hook can also be used to perform "pre-require" and "post-require" actions.Added support for
${^HOOK}{require__after}
which can be used to track what modules have been required after the fact.Regular expression opcodes (regops) now use a standardized structure layout that uses unions to expose data in different format. This means it should be much easier to extend or modify regops to use more memory. This has been used to make a number of regops track how many parens they contain.
Selected Bug Fixes
Avoid recursion and stack overflow parsing 'pack' template
An eval() as the last statement in a regex code block could trigger an interpreter panic; e.g.
/(?{ ...;
eval
{....}; })/
Disabling the
bareword_filehandles
feature no longer treatsprint Class->method
as an error. [GH #19704]When a Perl subroutine tail-calls an XS subroutine using
goto &xs_sub
, the XS subroutine can now correctly determine its calling context. Previously it was always reported as scalar.In addition, where the Perl subroutine is freed at the same time:
sub
foo {
*foo
=
sub
{};
goto
&xs_sub
}
this formerly could lead to crashes if the XS subroutine tried to use the value of
PL_op
, since this was being set to NULL. This is now fixed.setsockopt() now uses the mechanism added in 5.36 to better distinguish between numeric and string values supplied as the
OPTVAL
parameter. [GH #18761]4-argument
select()
now rejects strings with code points above 255. Additionally, for code points 128-255, this operator will now always give the corresponding octet to the OS, regardless of how Perl stores such code points in memory. (Previously Perl leaked its internal string storage to the OS.) [GH #19882]Fix panic issue from
val {} inside /(?{...})/
[GH #19390]Fix multiple compiler warnings from regexp.c, locale.c [GH #19915]
Fix a bug with querying locales on platforms that don't have
LC_NUMERIC
[GH #19890]Prevent undefined behaviour in
S_maybe_multideref()
.Avoid signed integer overflow in
use integer
ops.Avoid adding an offset to a NULL pointer in
hv_delete_common
.PerlIO::get_layers will now accept IO references too
Previously it would only take glob references or names of globs. Now it will also accept IO references.
Fixes to memory handling for
PL_splitstr
:If a thread was created the allocated string would be freed twice.
If two
-F
switches were supplied the memory allocated for the first switch wouldn't be freed.
Correctly handle
OP_ANONCODE
ops generated by CPAN modules that don't include the OPf_REF flag when propagating lvalue context. [GH #20532]POSIX::strxfrm now uses the
LC_CTYPE
locale category to specify its collation, ignoring any differingLC_COLLATE
. It doesn't make sense for a string to be encoded in one locale (say, ISO-8859-6, Arabic) and to collate it based on another (like ISO-8859-7, Greek). Perl assumes that the currentLC_CTYPE
locale correctly represents the encoding, and collates accordingly.Also, embedded
NUL
characters are now allowed in the input.If locale collation is not enabled on the platform (
LC_COLLATE
), the input is returned unchanged.Double FETCH during stringification of tied scalars returning an overloaded object have been fixed. The FETCH method should only be called once, but prior to this release was actually called twice. [GH #20574]
Writing to a magic variables associated with the selected output handle,
$^
,$~
,$=
,$-
and$%
, no longer crashes perl if the IO object has been cleared from the selected output handle. [GH #20733]Redefining a
use constant
list constant withuse constant
now properly warns. This changes the behaviour ofuse constant
but is a core change, not a change to constant.pm. [GH #20742]Redefining a
use constant
list constant with an empty prototype constant sub would result in an assertion failure. [GH #20742]Fixed a regression where the
INC
method for objects in@INC
would not be resolved byAUTOLOAD
, while it was in 5.36. TheINCDIR
method for objects in@INC
cannot be resolved byAUTOLOAD
asINC
would have been resolved first. [GH #20665]$SIG{__DIE__}
will now be called from eval when the code dies during compilation regardless of how it dies. This means that code expecting to be able to upgrade$@
into an object will be called consistently. In earlier versions of perl$SIG{__DIE__}
would not be called for certain compilation errors, for instance undeclared variables. For other errors it might be called if there were more than a certain number of errors, but not if there were less. Now you can expect that it will be called in every case.Compilation of code with errors used to inconsistently stop depending on the count and type of errors encountered. The intent was that after 10 errors compilation would halt, but bugs in this logic meant that certain types of error would be counted, but would not trigger the threshold check to stop compilation. Other errors would. With this release after at most 10 errors compilation will terminate, regardless of what type of error they were.
Note that you can change the maximum count by defining
PERL_STOP_PARSING_AFTER_N_ERRORS
to be something else during the configuration process. For instance./Configure ... -Accflags=
'-DPERL_STOP_PARSING_AFTER_N_ERRORS=100'
would allow up to 100 errors.
The API function "my_snprintf" in perlapi now prints a non-dot decimal point if the perl code it ultimately is called from is in the scope of
use locale
and the locale in effect calls for that.A number of bugs related to capture groups in quantified groups in regular expression have been fixed, especially in alternations. For example in a pattern like:
"foobazfoobar"
=~ /((foo)baz|foo(bar))+/
the regex variable
$2
will not be "foo" as it once was, it will be undef.Bugs with regex backreference operators that are inside of a capture group have been fixed. For instance:
"xa=xaaa"
=~ /^(xa|=?\1a){2}\z/
will now correctly not match. [GH #10073]
SSGROW()
andSSCHECK()
have been reworked to ensure that the requested space is actually allocated.SSCHECK()
is now an alias forSSGROW()
.
Acknowledgements
Perl 5.38.0 represents approximately 12 months of development since Perl 5.36.0 and contains approximately 290,000 lines of changes across 1,500 files from 100 authors.
Excluding auto-generated files, documentation and release tools, there were approximately 190,000 lines of changes to 970 .pm, .t, .c and .h files.
Perl continues to flourish into its fourth decade thanks to a vibrant community of users and developers. The following people are known to have contributed the improvements that became Perl 5.38.0:
Alex, Alexander Nikolov, Alex Davies, Andreas König, Andrew Fresh, Andrew Ruthven, Andy Lester, Aristotle Pagaltzis, Arne Johannessen, A. Sinan Unur, Bartosz Jarzyna, Bart Van Assche, Benjamin Smith, Bram, Branislav Zahradník, Brian Greenfield, Bruce Gray, Chad Granum, Chris 'BinGOs' Williams, chromatic, Clemens Wasser, Craig A. Berry, Dagfinn Ilmari Mannsåker, Dan Book, danielnachun, Dan Jacobson, Dan Kogai, David Cantrell, David Golden, David Mitchell, E. Choroba, Ed J, Ed Sabol, Elvin Aslanov, Eric Herman, Felipe Gasper, Ferenc Erki, Firas Khalil Khana, Florian Weimer, Graham Knop, Håkon Hægland, Harald Jörg, H.Merijn Brand, Hugo van der Sanden, James E Keenan, James Raspass, jkahrman, Joe McMahon, Johan Vromans, Jonathan Stowe, Jon Gentle, Karen Etheridge, Karl Williamson, Kenichi Ishigaki, Kenneth Ölwing, Kurt Fitzner, Leon Timmermans, Li Linjie, Loren Merritt, Lukas Mai, Marcel Telka, Mark Jason Dominus, Mark Shelor, Matthew Horsfall, Matthew O. Persico, Mattia Barbon, Max Maischein, Mohammad S Anwar, Nathan Mills, Neil Bowers, Nicholas Clark, Nicolas Mendoza, Nicolas R, Paul Evans, Paul Marquess, Peter John Acklam, Peter Levine, Philippe Bruhat (BooK), Reini Urban, Renee Baecker, Ricardo Signes, Richard Leach, Russ Allbery, Scott Baker, Sevan Janiyan, Sidney Markowitz, Sisyphus, Steve Hay, TAKAI Kousuke, Todd Rinaldo, Tomasz Konojacki, Tom Stellard, Tony Cook, Tsuyoshi Watanabe, Unicode Consortium, vsfos, Yves Orton, Zakariyya Mughal, Zefram, 小鸡.
The list above is almost certainly incomplete as it is automatically generated from version control history. In particular, it does not include the names of the (very much appreciated) contributors who reported issues to the Perl bug tracker.
Many of the changes included in this version originated in the CPAN modules included in Perl's core. We're grateful to the entire CPAN community for helping Perl to flourish.
For a more complete list of all of Perl's historical contributors, please see the AUTHORS file in the Perl source distribution.
Reporting Bugs
If you find what you think is a bug, you might check the perl bug database at https://github.com/Perl/perl5/issues. There may also be information at http://www.perl.org/, the Perl Home Page.
If you believe you have an unreported bug, please open an issue at https://github.com/Perl/perl5/issues. Be sure to trim your bug down to a tiny but sufficient test case.
If the bug you are reporting has security implications which make it inappropriate to send to a public issue tracker, then see "SECURITY VULNERABILITY CONTACT INFORMATION" in perlsec for details of how to report the issue.
Give Thanks
If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by running the perlthanks
program:
perlthanks
This will send an email to the Perl 5 Porters list with your show of thanks.
SEE ALSO
The Changes file for an explanation of how to view exhaustive details on what changed.
The INSTALL file for how to build Perl.
The README file for general stuff.
The Artistic and Copying files for copyright information.