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Perl 5.24


A new perl 5.24 version brings a lot of changes done over a year of development. Perl 5.24 will be released 5/9/2016. See 5.24.0 perldelta for more details about preparing release.


Current status

Completed items

  • Get dedicated build-root from rel-engs (f25-perl)
  • Define perl_bootstrap in perl-srpm-macros
  • Rebase perl to 5.24.0
  • Build new perl 5.24 keeping old COMPAT Provides
  • Rebuild dual-lived packages (otherwise yum recommends --skip-broken and fails)
  • Rebuild packages needed for minimal build-root
  • Rebuild packages needed for building source packages from git repository
  • Remove old perl(:MODULE_COMPAT_5.22.*) from perl
  • Undefine perl_bootstrap
  • Rebuild packages having perl_bootstrap condition in spec file
  • Rebuild other packages: Use Fedora::Rebuild dependency solver
  • Rebuild all updated packages
  • Merge dedicated build-root to rawhide and remove the dedicated one by rel-engs
  • Synchronize packages upgraded in f25 build root
  • Rebuilt Perl packages: 2862 of 2865 done (99.90 %)
  • Unfixable packages retired (1)

Items in progress

Items to be done

Detailed Description

New perl is released every year and updates containing mainly bug fixes follow during the year. The 5.24.0 version is stable release this year.

Benefit to Fedora

Up-to-date and latest perl release will be delivered to Fedora users.


Every Perl package will be rebuilt in a dedicated f25-perl build-root against perl 5.24.0 and then if no major problem emerges the packages will be merged back to f25 build-root.

  • Proposal owners:

New perl and all packages requiring perl or a Perl module will be rebuilt into f25-perl build-root.

  • Other developers:

Owners of packages that fail to rebuild, mainly perl-sig users, will be asked using Bugzilla to fix or remove their packages from the distribution.

  • Release engineering:

Release engineers will be asked for new f25-perl build-root inheriting from f25 build-root. After successful finishing the rebuild, they will be asked to merge f25-perl packages back to f25 build-root.

  • Policies and guidelines:

No policies have to be modified to complete this change.

Upgrade/compatibility impact

Vast majority of functionality will be preserved. Only the packages that failed to build against perl 5.24 will be removed from the distribution. That will require to remove those packages from existing systems otherwise package manager will encounter unsatisfied dependencies.

How To Test

Try upgrading from Fedora 24 to 25. Try some Perl application to verify they work as expected. Try embedded perl in slapd or snmpd.

User Experience

There should not be any remarkable change in user experience.


There is more than 2700 packages depending on perl. Most of them are expected not to break. Finishing this change can be endangered only by critical changes in a toolchain.

Contingency Plan

If we find perl 5.24 is not suitable for Fedora 25, we will revert back to perl 5.22 and we drop the temporary build-root with already rebuilt packages.

  • Contingency deadline: branching Fedora 25 from Rawhide.
  • Blocks release? No.


Release Notes

  • New features:
    • Unicode 8.0 is now supported.
    • An exception will be raised when closing an in-place output file fails.
    • (?[ ]) will successfully compile when use locale is in effect.
    • Integer shift (<< and >>) now more explicitly defined. Negative shifts are reverse shifts.
    • printf and sprintf now allow reordered precision arguments.
    • When passing the SA_SIGINFO flag to sigaction, the errno, status, uid, pid, addr and band fields are included in the hash passed to the handler, if supported by the platform.
    • Hashbang redirection was extended also to Perl 6.
  • Changes:
    • Postfix dereferencing is no longer experimental.
    • Remove duplicate environment variables from environ.
    • More regular expression patterns are now checked for validity at compilation time, and invalid ones will cause the program to not compile.
    • Using \N{} is a fatal error under experimental feature "'strict' mode" in re.
    • A my, our, or state declaration is no longer allowed inside of another my, our, or state declaration.
    • The /\C/ character class has been removed.
    • Using chdir(\'\') or chdir(undef) to change working directory to a home directory fails now. Use chdir() instead.
    • ASCII characters in variable names must now be all visible.
    • $Carp::MaxArgNums is supposed to be the number of arguments to display.
    • Only blanks and tabs are now allowed within [...] within (?[...]).
    • Matching fixed string regular expression is now faster in most cases.
  • Removed features:
    • The autoderef feature has been removed.
    • Lexical $_ has been removed.
    • no longer get installed, as they are not used by
    • Using code points above the platform's IV_MAX is now deprecated.
    • Bitwise operations on strings containing code points above 0xFF is deprecated. Instead, encode these strings to byte strings first.
    • sysread(), syswrite(), recv() and send() are deprecated on :utf8 handles.