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perldelta - what is new for perl v5.15.0


This document describes differences between the 5.15.0 release and the 5.14.0 release.

If you are upgrading from an earlier release such as 5.12.0, first read perl5140delta, which describes differences between 5.12.0 and 5.14.0.

Some of the changes have been included in Perl 5.14.1. These are indicated with a "(5.14.1)" marker.

Core Enhancements

CORE:: works on all keywords

The CORE:: prefix can now be used on keywords enabled by feature.pm, even outside the scope of use feature. Relevant documentation files CORE, feature, perlfunc, perlsub, and perlsyn have been updated.

continue no longer requires the "switch" feature

The continue keyword has two meanings. It can introduce a continue block after a loop, or it can exit the current when block. Up till now, the latter meaning was only valid with the "switch" feature enabled, and was a syntax error otherwise. Since the main purpose of feature.pm is to avoid conflicts with user-defined subroutines, there is no reason for continue to depend on it.

$$ can be assigned to

$$ was made read-only in Perl 5.8.0. But only sometimes: local $$ would make it writable again. Some CPAN modules were using local $$ or XS code to bypass the read-only check, so there is no reason to keep $$ read-only. (This change also allowed a bug to be fixed while maintaining backward compatibility.)

Features inside the debugger

The current Perl's feature bundle is now enabled for commands entered in the interactive debugger.

\N{...} can now have Unicode loose name matching

This is described in the charnames item in "Updated Modules and Pragmata" below.

Breakpoints with file names

The debugger's "b" command for setting breakpoints now allows a line number to be prefixed with a file name. See "b [file]:[line] [condition]" in perldebug.


No changes since 5.14.0.

Incompatible Changes

Tying scalars that hold typeglobs

Attempting to tie a scalar after a typeglob was assigned to it would instead tie the handle in the typeglob's IO slot. This meant that it was impossible to tie the scalar itself. Similar problems affected tied and untie: tied $scalar would return false on a tied scalar if the last thing returned was a typeglob, and untie $scalar on such a tied scalar would do nothing.

We fixed this problem before Perl 5.14.0, but it caused problems with some CPAN modules, so we put in a deprecation cycle instead.

Now the deprecation has been removed and this bug has been fixed. So tie $scalar will always tie the scalar, not the handle it holds. To tie the handle, use tie *$scalar (with an explicit asterisk). The same applies to tied *$scalar and untie *$scalar.

IPC::Open3 no longer provides xfork(), xclose_on_exec() and xpipe_anon()

All three functions were private, undocumented and unexported. They do not appear to be used by any code on CPAN. Two have been inlined and one deleted entirely.

$$ no longer caches PID

Previously, if one embeds Perl or uses XS and calls fork(3) from C, Perls notion of $$ could go out of sync with what getpid() returns. By always fetching the value of $$ via getpid(), this potential bug is eliminated. Code that depends on the caching behavior will break. As described in "Core Enhancements", $$ is now writable, but it will be reset during a fork.


There have been no deprecations since 5.14.0.

Performance Enhancements

There are no benchmarked enhancements since 5.14.0.

Modules and Pragmata

New Modules and Pragmata


Updated Modules and Pragmata

  • charnames has been updated from version 1.18 to version 1.22

    charnames can now be invoked with a new option, :loose, which is like the existing :full option, but enables Unicode loose name matching. Details are in "LOOSE MATCHES" in charnames.

  • constant has been updated from version 1.21 to 1.22.

  • Archive::Extract has been upgraded from version 0.48 to version 0.52

    Includes a fix for FreeBSD to only use unzip if it is located in /usr/local/bin, as FreeBSD 9.0 will ship with a limited unzip in /usr/bin.

  • Attribute::Handlers updated from version 0.88 to 0.91

  • B has been upgraded from version 1.29 to version 1.30.

  • B::Deparse has been upgraded from version 1.03 to 1.05. (Perl 5.14.1 had version 1.04.)

    It addresses two regressions in Perl 5.14.0:

    • Deparsing of the glob operator and its diamond (<>) form now works again [perl #90898] (5.14.1).

    • The presence of subroutines named :::: or :::::: no longer causes B::Deparse to hang (5.14.1).

    Plus a few other bugs:

    • Deparsing of handle keys, each and value with a scalar argument now works [perl #91008].

    • readpipe followed by a complex expression (as opposed to a simple scalar variable) now works.

    • It now puts CORE:: in front of overridable core keywords if they conflict with user-defined subroutines.

    • Deparsing assignment to an lvalue method specified as a variable ($obj->$method = ...) used not to work [perl #62498].

  • CGI has been upgraded from version 3.52 to version 3.54

    The DELETE HTTP verb is now supported.

  • Compress::Zlib has been upgraded from version 2.033 to version 2.035

  • Compress::Raw::Bzip2 has been upgraded from version 2.033 to version 2.035

  • Compress::Raw::Zlib has been upgraded from version 2.033 to version 2.035

  • CPAN::Meta has been upgraded from version 2.110440 to version 2.110930

  • CPANPLUS has been upgraded from version 0.9103 to version 0.9105

    Now understands specifying modules to install in the format 'Module/Type.pm'

  • CPANPLUS::Dist::Build has been upgraded from version 0.54 to version 0.56

  • Data::Dumper has been upgraded from version 2.128 to 2.131.

  • DB_File has been upgraded from version 1.821 to version 1.822

    Warnings are now in sync with perl's

  • Digest::SHA has been upgraded from version 5.61 to version 5.62

    No longer loads MIME::Base64 as this was unnecessary.

  • Devel::Peek has been upgraded from version 1.07 to 1.08.

    Its fill_mstats function no longer refuses to write to copy-on-write scalars.

  • Encode has been upgraded from version 2.42 to version 2.43

    Missing aliases added, a deep recursion error fixed and various documentation updates.

  • ExtUtils::CBuilder updated from version 0.280203 to 0.280204.

    The new version appends CFLAGS and LDFLAGS to their Config.pm counterparts.

  • Filter::Util::Call has been upgraded from version 1.08 to version 1.39

    decrypt fixed to work with v5.14.0

  • Filter::Simple updated from version 0.85 to 0.87

  • FindBin updated from version 1.50 to 1.51.

    It no longer returns a wrong result if a script of the same name as the current one exists in the path and is executable.

  • JSON::PP has been upgraded from version 2.27105 to version 2.27200

    Fixed incr_parse decoding string more correctly.

  • I18N::LangTags has been upgraded from version 0.35_01 to version 0.36.

    Fix broken URLs for RFCs.

  • IPC::Open3 has been upgraded from version 1.10 to version 1.11.

    • Fixes a bug which prevented use of open3 on Windows when *STDIN, *STDOUT or *STDERR had been localized.

    • Fixes a bug which prevented duplicating numeric file descriptors on Windows.

  • Math::BigFloat has been upgraded from version 1.993 to 1.994.

    The numify method has been corrected to return a normalised Perl number (the result of 0 + $thing), instead of a string [rt.cpan.org #66732].

  • Math::BigInt has been upgraded from version 1.994 to 1.995.

    It provides a new bsgn method that complements the babs method.

    It fixes the internal objectify function's handling of "foreign objects" so they are converted to the appropriate class (Math::BigInt or Math::BigFloat).

  • Math::Complex has been upgraded from version 1.56 to version 1.57 and Math::Trig has been upgraded from version 1.20 to version 1.21.

    Fixes include: correct copy constructor usage; fix polarwise formatting with numeric format specifier; and more stable great_circle_direction algorithm.

  • Module::CoreList has been upgraded from version 2.49 to 2.51.

    Updated for v5.12.4, v5.14.1 and v5.15.0

  • mro has been updated to remove two broken URLs in the documentation.

  • Object::Accessor has been upgraded from version 0.38 to version 0.42

    Eliminated use of exists on array elements which has been deprecated.

  • ODBM_File has been upgraded from version 1.10 to version 1.11.

    The XS code is now compiled with PERL_NO_GET_CONTEXT, which will aid performance under ithreads.

  • PerlIO::encoding has been upgraded from version 0.14 to 0.15

  • PerlIO::scalar has been upgraded from version 0.11 to 0.12.

    It fixes a problem with open my $fh, ">", \$scalar not working if $scalar is a copy-on-write scalar.

    It also fixes a hang that occurs with readline or <$fh> if a typeglob has been assigned to $scalar [perl #92258].

  • Pod::Perldoc has been upgraded from version 3.15_03 to 3.15_05.

    It corrects the search paths on VMS [perl #90640]. (5.14.1)

  • Storable has been upgraded from version 2.27 to version 2.28.

    It no longer turns copy-on-write scalars into read-only scalars when freezing and thawing.

  • Sys::Syslog has been upgraded from version 0.27 to version 0.29

    Large number of Request Tickets resolved.

  • Time::HiRes has been upgraded from version 1.9721_01 to version 1.9722.

    Portability fix, and avoiding some compiler warnings.

  • Unicode::Collate has been upgraded from version 0.73 to version 0.76

    Updated to CLDR 1.9.1

  • Unicode::Normalize has been upgraded from version 1.10 to version 1.12

    Fixes for the removal of unicore/CompositionExclusions.txt from core.

  • XSLoader has been upgraded from version 0.13 to version 0.15

Removed Modules and Pragmata

As promised in Perl 5.14.0's release notes, the following modules have been removed from the core distribution, and if needed should be installed from CPAN instead.

  • Devel::DProf has been removed from the Perl core. Prior version was 20110228.00.

  • Shell has been removed from the Perl core. Prior version was 0.72_01.


New Documentation


Changes to Existing Documentation


  • Added portability caveats related to using kill on forked process.


  • Documentation for use now includes a pointer to if.pm (5.14.1)

  • given, when and default are now listed in perlfunc (5.14.1).

  • The examples for the select function no longer use strings for file handles.


  • Some of the function descriptions in perlguts were confusing, as it was not clear whether they referred to the function above or below the description. This has been clarified [perl #91790].


  • perllol has been expanded with examples using the new push $scalar syntax introduced in Perl 5.14.0 (5.14.1).


  • perlmod now states explicitly that some types of explicit symbol table manipulation are not supported. This codifies what was effectively already the case [perl #78074].


  • The explanation of bitwise operators has been expanded to explain how they work on Unicode strings (5.14.1).

  • The section on the triple-dot or yada-yada operator has been moved up, as it used to separate two closely related sections about the comma operator (5.14.1).

  • More examples for m//g have been added (5.14.1).

  • The <<\FOO here-doc syntax has been documented (5.14.1).


  • The tips on which formatting codes to use have been corrected and greatly expanded.

  • There are now a couple of example one-liners for previewing POD files after they have been edited.




  • perlrun has undergone a significant clean-up. Most notably, the -0x... form of the -0 flag has been clarified, and the final section on environment variables has been corrected and expanded (5.14.1).


  • Documented the required syntax for tying handles.


  • The documentation for $! has been corrected and clarified. It used to state that $! could be undef, which is not the case. It was also unclear as to whether system calls set C's errno or Perl's $! [perl #91614].

  • Documentation for $$ has been amended with additional cautions regarding changing the process ID.


  • The invocation documentation for WIFEXITED, WEXITSTATUS, WIFSIGNALED, WTERMSIG, WIFSTOPPED, and WSTOPSIG has been corrected (5.14.1).


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 Warnings

Useless assignment to a temporary

Assigning to a temporary returned from an XS lvalue subroutine now produces a warning [perl #31946].

Changes to Existing Diagnostics


Utility Changes


Configuration and Compilation

  • regexp.h has been modified for compatibility with GCC's -Werror option, as used by some projects that include perl's header files (5.14.1).

  • USE_LOCALE{,_COLLATE,_CTYPE,_NUMERIC} have been added the output of perl -V as they have affect the behaviour of the interpreter binary (albeit only in a small area).

  • The code and tests for IPC::Open2 have been moved from ext/IPC-Open2 into ext/IPC-Open3, as IPC::Open2::open2() is implemented as a thin wrapper around IPC::Open3::_open3(), and hence is very tightly coupled to it.

  • The magic types and magic vtables are now generated from data in a new script regen/mg_vtable.pl, instead of being maintained by hand. As different EBCDIC variants can't agree on the code point for '~', the character to code point conversion is done at build time by generate_uudmap to a new generated header mg_data.h. PL_vtbl_bm and PL_vtbl_fm are now defined by the pre-processor as PL_vtbl_regexp, instead of being distinct C variables. PL_vtbl_sig has been removed.

  • Building with -DPERL_GLOBAL_STRUCT works again. This configuration is not generally used.

  • Perl configured with MAD now correctly frees MADPROP structures when OPs are freed. MADPROPs are now allocated with PerlMemShared_malloc()


There have been no significant changes to the process for testing a newly-built perl.

See the source code commit history for changes to individual test files.

Platform Support

New Platforms


Discontinued Platforms


Platform-Specific Notes


  • No longer overrides possible extra $ccflags values given to Configure on GNU/Hurd. C.f. Bug-Debian: http://bugs.debian.org/587901

Mac OS X

  • Clarified Apple Developer Tools requirements in README.macosx

  • Mac OS X specific compilation instructions have been clarified (5.14.1)


  • Supplied makefile.mk patched to support gcc-4.x.x and README.win32 updated accordingly. [perl #91354]


  • Updated the list of required packages for building perl to reflect Solaris 9 and 10 in README.solaris [perl #90850] (5.14.1)

Ubuntu Linux

  • The ODBM_File installation process has been updated with the new library paths on Ubuntu natty [perl #90106] (5.14.1)

  • h2ph now gets the include paths from gcc correctly. This stopped working when Ubuntu switched to a "multiarch" setup [perl #90122].

Internal Changes

  • The compiled representation of formats is now stored via the mg_ptr of their PERL_MAGIC_fm. Previously it was stored in the string buffer, beyond SvLEN(), the regular end of the string. SvCOMPILED() and SvCOMPILED_{on,off}() now exist solely for compatibility for XS code. The first is always 0, the other two now no-ops. (5.14.1)

  • Some global variables have been marked const, members in the interpreter structure have been re-ordered, and the opcodes have been re-ordered. The op OP_AELEMFAST has been split into OP_AELEMFAST and OP_AELEMFAST_LEX.

  • When empting a hash of its elements (e.g. via undef(%h), or %h=()), HvARRAY field is no longer temporarily zeroed. Any destructors called on the freed elements see the remaining elements. Thus, %h=() becomes more like delete $h{$_} for keys %h.

  • Boyer-Moore compiled scalars are now PVMGs, and the Boyer-Moore tables are now stored via the mg_ptr of their PERL_MAGIC_bm. Previously they were PVGVs, with the tables stored in the string buffer, beyond SvLEN(). This eliminates the last place where the core stores data beyond SvLEN().

  • Simplified logic in Perl_sv_magic() introduces a small change of behaviour for error cases involving unknown magic types. Previously, if Perl_sv_magic() was passed a magic type unknown to it, it would

    1. Croak "Modification of a read-only value attempted" if read only

    2. Return without error if the SV happened to already have this magic

    3. otherwise croak "Don't know how to handle magic of type \\%o"

    Now it will always croak "Don't know how to handle magic of type \\%o", even on read only values, or SVs which already have the unknown magic type.

Selected Bug Fixes

Regular expressions and character classes

  • The new (in 5.14.0) regular expression modifier /a when repeated like /aa forbids the characters outside the ASCII range that match characters inside that range from matching under /i. This did not work under some circumstances, all involving alternation, such as:

     "\N{KELVIN SIGN}" =~ /k|foo/iaa;

    succeeded inappropriately. This is now fixed.

  • 5.14.0 introduced some memory leaks in regular expression character classes such as [\w\s], which have now been fixed (5.14.1)

  • An edge case in regular expression matching could potentially loop. This happened only under /i in bracketed character classes that have characters with multi-character folds, and the target string to match against includes the first portion of the fold, followed by another character that has a multi-character fold that begins with the remaining portion of the fold, plus some more.

     "s\N{U+DF}" =~ /[\x{DF}foo]/i

    is one such case. \xDF folds to "ss". (5.14.1)


  • Fixed memory leak regression in regular expression compilation under threading


  • A number of edge cases have been fixed with formats and formline; in particular, where the format itself is potentially variable (such as with ties and overloading), and where the format and data differ in their encoding. In both these cases, it used to possible for the output to be corrupted [perl #91032].

  • formline no longer converts its argument into a string in-place. So passing a reference to formline no longer destroys the reference [perl #79532].

Copy-on-write scalars

Copy-on-write scalars were introduced in 5.8.0, but most Perl code did not encounter them (they were used mostly internally). Perl 5.10.0 extended them, such that assigning __PACKAGE__ or a hash key to a scalar would make it copy-on-write. Several parts of Perl were not updated to account for them, but have now been fixed.

  • utf8::decode had a nasty bug that would modify copy-on-write scalars' string buffers in place (i.e., skipping the copy). This could result in hashes having two elements with the same key [perl #91834].

  • Lvalue subroutines were not allowing COW scalars to be returned. This was fixed for lvalue scalar context in Perl 5.12.3 and 5.14.0, but list context was not fixed until this release.

  • Elements of restricted hashes (see the fields pragma) containing copy-on-write values couldn't be deleted, nor could such hashes be cleared (%hash = ()).

  • Localising a tied variable used to make it read-only if it contained a copy-on-write string.

  • Storable, Devel::Peek and PerlIO::scalar had similar problems. See "Updated Modules and Pragmata", above.

lvalue subroutines

There have been various fixes to lvalue subroutines.

  • Explicit return now returns the actual argument passed to return, instead of copying it [perl #72724] [perl #72706].

    Note: There are still some discrepancies between explicit and implicit return, which will hopefully be resolved soon. So the exact behaviour is not set in stone yet.

  • Lvalue subroutines used to enforce lvalue syntax (i.e., whatever can go on the left-hand side of =) for the last statement and the arguments to return. Since lvalue subroutines are not always called in lvalue context, this restriction has been lifted.

  • Lvalue subroutines are less restrictive as to what values can be returned. It used to croak on values returned by shift and delete and from other subroutines, but no longer does so [perl #71172].

  • Empty lvalue subroutines (sub :lvalue {}) used to return @_ in list context. In fact, all subroutines used to, but regular subs were fixed in Perl 5.8.2. Now lvalue subroutines have been likewise fixed.

  • Lvalue subroutines used to copy their return values in rvalue context. Not only was this a waste of CPU cycles, but it also caused bugs. A ($) prototype would cause an lvalue sub to copy its return value [perl #51408], and while(lvalue_sub() =~ m/.../g) { ... } would loop endlessly [perl #78680].

  • Autovivification now works on values returned from lvalue subroutines [perl #7946].

  • When called in pass-by-reference context (e.g., subroutine arguments or a list passed to for), an lvalue subroutine returning arrays or hashes used to bind the arrays (or hashes) to scalar variables--something that is not supposed to happen. This could result in "Bizarre copy of ARRAY" errors or print ignoring its arguments. It also made nonsensical code like @{\$_} "work". This was fixed in 5.14.0 if an array were the first thing returned from the subroutine (but not for $scalar, @array or hashes being returned). Now a more general fix has been applied [perl #23790].

  • When called in pass-by-reference context, lvalue subroutines used to copy any read-only value that was returned. E.g., sub :lvalue { $] } would not return $], but a copy of it.

  • Assignment to keys returned from an lvalue sub used not to work, but now it does.

  • Applying the :lvalue attribute to an XSUB or to an aliased subroutine stub with sub foo :lvalue; syntax stopped working in Perl 5.12. This has been fixed.

  • A bug has been fixed that would cause a "Use of freed value in iteration" error if the next two hash elements that would be iterated over are deleted [perl #85026]. (5.14.1)

  • Freeing deeply nested hashes no longer crashes [perl #44225].

  • Deleting the current hash iterator (the hash element that would be returend by the next call to each) in void context used not to free it. The hash would continue to reference it until the next iteration. This has been fixed [perl #85026].

Other notable fixes

  • Passing the same constant subroutine to both index and formline no longer causes one or the other to fail [perl #89218]. (5.14.1)

  • List assignment to lexical variables declared with attributes in the same statement (my ($x,@y) : blimp = (72,94)) stopped working in Perl 5.8.0. It has now been fixed.

  • Perl 5.10.0 introduced some faulty logic that made "U*" in the middle of a pack template equivalent to "U0" if the input string was empty. This has been fixed [perl #90160].

  • Destructors on objects were not called during global destruction on objects that were not referenced by any scalars. This could happen if an array element were blessed (e.g., bless \$a[0]) or if a closure referenced a blessed variable (bless \my @a; sub foo { @a }).

    Now there is an extra pass during global destruction to fire destructors on any objects that might be left after the usual passes that check for objects referenced by scalars [perl #36347].

    This bug fix was added in Perl 5.13.9, but caused problems with some CPAN modules that were relying on the bug. Since it was so close to Perl 5.14.0, the fix was reverted in 5.13.10, to allow more time for the modules to adapt. Hopefully they will be fixed soon (see "Known Problems", below).

  • given was not calling set-magic on the implicit lexical $_ that it uses. This meant, for example, that pos would be remembered from one execution of the same given block to the next, even if the input were a different variable [perl #84526].

  • The "R" command for restarting a debugger session has been fixed to work on Windows, or any other system lacking a POSIX::_SC_OPEN_MAX constant [perl #87740].

  • Fixed a case where it was possible that a freed buffer may have been read from when parsing a here document [perl #90128]. (5.14.1)

  • The study function could become confused if fed a string longer than 2**31 characters. Now it simply skips such strings.

  • each(ARRAY) is now wrapped in defined(...), like each(HASH), inside a while condition [perl #90888].

  • In @INC filters (subroutines returned by subroutines in @INC), $_ used to misbehave: If returned from a subroutine, it would not be copied, but the variable itself would be returned; and freeing $_ (e.g., with undef *_) would cause perl to crash. This has been fixed [perl #91880].

  • An ASCII single quote (') in a symbol name is meant to be equivalent to a double colon (::) except at the end of the name. It was not equivalent if followed by a null character, but now it is [perl #88138].

  • The abbreviations for four C1 control characters MW PM, RI, and ST were previously unrecognized by \N{}, vianame(), and string_vianame().

  • Some cases of threads crashing due to memory allocation during cloning have been fixed [perl #90006].

  • Attempting to goto out of a tied handle method used to cause memory corruption or crashes. Now it produces an error message instead [perl #8611].

  • Perl skips copying values returned from a subroutine if it thinks the value is not in use elsewhere. Due to faulty logic, this would happen with the result of delete, shift or splice, even if the result was referenced elsewhere. So \sub { delete $_[0] }->($x) would return a reference to $x. This has been fixed [perl #91844].

Known Problems

  • The fix for perl #36347 causes test failures for Gtk2 and Tk on some systems [perl #82542].

  • The changes to tie cause test failures for the JS module.

  • The changes to $$ cause test failures for the Event module.

  • YAML::Syck has (undiagnosed) test failures.


Perl 5.15.0 represents approximatly five weeks of development since Perl 5.14.0 and contains approximately 54,000 lines of changes across 618 files from 57 authors.

Perl continues to flourish into its third decade thanks to a vibrant community of users and developers. The following people are known to have contributed the improvements that became Perl 5.15.0:

Alan Haggai Alavi, Bo Johansson, Bo Lindbergh, brian d foy, Chia-liang Kao, Chris 'BinGOs' Williams, Claudio Ramirez, Craig A. Berry, David Golden, David Leadbeater, David Mitchell, Dennis Kaarsemaker, Dominic Hargreaves, Eric Brine, Father Chrysostomos, Florian Ragwitz, George Greer, Gisle Aas, H.Merijn Brand, Hojung Yoon, Ian Goodacre, Jesse Vincent, Jim Cromie, Johan Vromans, John Hawkinson, John P. Linderman, Joshua ben Jore, Karl Williamson, Kevin J. Woolley, Leo Lapworth, Leon Brocard, Leon Timmermans, Louis Strous, Marcel Grünauer, Martin Hasch, Max Maischein, Michael Witten, Moritz Lenz, Nicholas Clark, Niko Tyni, Nuno Carvalho, Pau Amma, Peter John Acklam, Robin Barker, Salvador Fandiño, Samuel Thibault, Shawn M Moore, Shigeya Suzuki, Shlomi Fish, Sisyphus, Steffen Müller, Todd Rinaldo, Tom Christiansen, Tony Cook, Vladimir Timofeev, Zefram and Zsbán Ambrus.

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 articles recently posted to the comp.lang.perl.misc newsgroup and the perl bug database at http://rt.perl.org/perlbug/ . There may also be information at http://www.perl.org/ , the Perl Home Page.

If you believe you have an unreported bug, please run the perlbug program included with your release. Be sure to trim your bug down to a tiny but sufficient test case. Your bug report, along with the output of perl -V, will be sent off to perlbug@perl.org to be analysed by the Perl porting team.

If the bug you are reporting has security implications, which make it inappropriate to send to a publicly archived mailing list, then please send it to perl5-security-report@perl.org. This points to a closed subscription unarchived mailing list, which includes all the core committers, who will be able to help assess the impact of issues, figure out a resolution, and help co-ordinate the release of patches to mitigate or fix the problem across all platforms on which Perl is supported. Please only use this address for security issues in the Perl core, not for modules independently distributed on CPAN.


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.