Changes/perl5.32

Perl 5.32

Summary

A new perl 5.32 version brings a lot of changes done over a year of development. Perl 5.32 was released in June 20th 2020. See 5.32.0 perldelta for more details about new release.

Owner

• Name: Jitka Plesníková
• Email: <jplesnik@redhat.com>
• Name: Petr Písař
• Email: <ppisar@redhat.com>

Current Status

• Targeted release: Fedora 33
• Last updated: 2020-08-24
• FESCo issue: #2376
• Tracker bug: #1827798
• Release notes tracker: #497

Completed Items

• Get dedicated build-root from rel-engs (f33-perl)
• Upstream to release Perl 5.32
• Define perl_bootstrap in perl-srpm-macros
• Rebase perl to 5.32.0
• Rebuild dual-lived packages (otherwise dnf recommends --skip-broken and fails)
• Rebuild packages needed for minimal build-root
• Rebuild packages needed for building source packages from git repository
• Rebuild other packages: Use Fedora::Rebuild dependency solver
• Undefine perl_bootstrap
• Rebuild packages having perl_bootstrap condition in spec file
• Rebuild all updated packages
• Final lists of results
• Merge dedicated build-root to rawhide and remove the dedicated one by rel-engs
• Synchronize packages upgraded in f33 build root
• Rebuild Perl packages: 3208 of 3208 done (100.00%)

Detailed Description

New perl is released every year and updates containing mainly bug fixes follow during the year. The 5.32.0 version is stable release this year.

Additionally, the perl-interpreter package will undergo further minimization, leading to splitting of a generic documentation (e.g. perlintro POD) into a perl-doc package and a perl debugger (perl -d invocation) into a perl-debugger package.

Benefit to Fedora

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

Scope

Every Perl package will be rebuilt in a dedicated f33-perl build-root against perl 5.32.0 and then if no major problem emerges the packages will be merged back to f33 build-root.

• Proposal owners:

New perl and all packages requiring perl or a Perl module will be rebuilt into f33-perl build-root.

• Other developers: N/A (not a System Wide Change)

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: #9387 (a check of an impact with Release Engineering is needed)

Release engineers will be asked for new f33-perl build-root inheriting from f33 build-root. After successful finishing the rebuild, they will be asked to merge f33-perl packages back to f33 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 5.32 will be removed from the distribution. That will require to remove those packages from the existing systems otherwise a package manager will encounter unsatisfied dependencies. The developers in Perl language are advised to install perl-doc and perl-debugger packages.

How To Test

Try upgrading from Fedora 32 to 33. 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. With the exception that previously locally installed modules with a CPAN clients will need a reinstallation.

Dependencies

There is more than 3200 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 5.32 is not suitable for Fedora 33, we will revert back to perl 5.30 and we drop the temporary build-root with already rebuilt packages.

• Contingency deadline: branching Fedora 33 from Rawhide.
• Blocks release? No.

Documentation

• 5.32.0 perldelta
• An announcement on the perl-devel mailing list
• An announcement on fedora-devel mailing list
• perl-interpreter split announcement

Release Notes

• Core Enhancements
  • Unicode 13.0 is supported
  • It is now possible to write qr/\p{Name=...}/, or qr!\p{na=/(SMILING|GRINNING) FACE/}!
  • It is now possible to write qr/\p{Name=...}/, or \p{Na=...}
  • The POSIX::mblen(), mbtowc, and wctomb functions now work on shift state locales and are thread-safe on C99 and above compilers when executed on a platform that has locale thread-safety; the length parameters are now optional.
  • The new experimental infix operator isa tests whether a given object is an instance of a given class or a class derived from it.
  • Alpha assertions are no longer experimental
  • Script runs are no longer experimental
  • Feature checks are now faster
  • Now can dump compiled patterns before optimization

• Removed Features and Incompatible Changes
  • Removed modules: B::Debug, Pod::Parser
  • Certain pattern matching features are now prohibited in compiling Unicode property value wildcard subpatterns
  • Stop pretending POSIX::mbstowcs and POSIX::wcstombs are supported
  • A bug fix for (?[...]) may have caused some patterns to no longer compile
  • \p{user-defined} properties now always override official Unicode ones
  • Modifiable variables are no longer permitted in constants
  • Use of vec on strings with code points above 0xFF is forbidden
  • Use of code points over 0xFF in string bitwise operators
  • Sys::Hostname::hostname() does not accept arguments
  • Plain "0" string now treated as a number for range operator
  • \K now disallowed in look-ahead and look-behind assertions