=encoding utf8 =head1 NAME [ this is a template for a new perldelta file. Any text flagged as XXX needs to be processed before release. ] perldelta - what is new for perl v5.45.1 =head1 DESCRIPTION This document describes differences between the 5.45.0 release and the 5.45.1 release. If you are upgrading from an earlier release such as 5.44.0, first read L, which describes differences between 5.44.0 and 5.45.0. =head1 Notice XXX Any important notices here =head1 Core Enhancements XXX New core language features go here. Summarize user-visible core language enhancements. Particularly prominent performance optimisations could go here, but most should go in the L section. [ List each enhancement as a =head2 entry ] =head2 Magic v2 This version introduces a whole new set of API functions, data structures, and related items that provides a new kind of variable magic; providing the ability to attach user-supplied trigger functions to behaviours on existing variables. The eventual intention of this new version is to extend magic with new trigger functions that can apply at different times to those currently supported, and to allow magic to be attached to new kinds of items than are currently permitted. Right now as of this iteration, it does not offer any new abilities but simply changes the shape and structure of existing things to allow space for those extensions to be made at a later date. For more details, see L. =head1 Security XXX Any security-related notices go here. In particular, any security vulnerabilities closed should be noted here rather than in the L section. [ List each security issue as a =head2 entry ] =head1 Incompatible Changes XXX For a release on a stable branch, this section aspires to be: There are no changes intentionally incompatible with 5.XXX.XXX If any exist, they are bugs, and we request that you submit a report. See L below. [ List each incompatible change as a =head2 entry ] =head1 Deprecations XXX Any deprecated features, syntax, modules etc. should be listed here. =head2 Module removals XXX Remove this section if not applicable. The following modules will be removed from the core distribution in a future release, and will at that time need to be installed from CPAN. Distributions on CPAN which require these modules will need to list them as prerequisites. The core versions of these modules will now issue C-category warnings to alert you to this fact. To silence these deprecation warnings, install the modules in question from CPAN. Note that these are (with rare exceptions) fine modules that you are encouraged to continue to use. Their disinclusion from core primarily hinges on their necessity to bootstrapping a fully functional, CPAN-capable Perl installation, not usually on concerns over their design. =over =item XXX XXX Note that deprecated modules should be listed here even if they are listed as an updated module in the L section. =back [ List each other deprecation as a =head2 entry ] =head1 Performance Enhancements XXX Changes which enhance performance without changing behaviour go here. There may well be none in a stable release. [ List each enhancement as an =item entry ] =over 4 =item * C has been added to streamline expressions such as C<(ref $x eq 'SCALAR')> where (i) the first operator is C or C, (ii) the comparison is C or C, and (iii) the value being compared against is one of the internal reftype strings mentioned in L, is C, or is the empty string C<''>. =item * Counting the number of matches within a string using the following common idiom is now more streamlined. C Instead of pushing all matches to the stack as mortal SVs, just so that the list assignment can count them, C maintains an internal count during matching and pushes just that upon completion. [GH #24558] =item * XXX =back =head1 Modules and Pragmata XXX All changes to installed files in F, F, F and F go here. If L is updated, generate an initial draft of the following sections using F. A paragraph summary for important changes should then be added by hand. In an ideal world, dual-life modules would have a F file that could be cribbed. The list of new and updated modules is modified automatically as part of preparing a Perl release, so the only reason to manually add entries here is if you're summarising the important changes in the module update. (Also, if the manually-added details don't match the automatically-generated ones, the release manager will have to investigate the situation carefully.) [ Within each section, list entries as an =item entry ] =head2 New Modules and Pragmata =over 4 =item * XXX Remove this section if F did not add any content here. =back =head2 Updated Modules and Pragmata =over 4 =item * L has been upgraded from version A.xx to B.yy. XXX If there was something important to note about this change, include that here. =back =head2 Removed Modules and Pragmata =over 4 =item * XXX Remove this section if F did not add any content here. =back =head1 Documentation XXX Changes to files in F go here. Consider grouping entries by file and be sure to link to the appropriate page, e.g. L. =head2 New Documentation XXX Changes which create B files in F go here. =head3 L XXX Description of the purpose of the new file here =head2 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 L. XXX Changes which significantly change existing files in F go here. However, any changes to F should go in the L section. Additionally, the following selected changes have been made: =head3 L =over 4 =item * XXX Description of the change here =back =head1 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 L. XXX New or changed warnings emitted by the core's C code go here. Also include any changes in L that reconcile it to the C code. =head2 New Diagnostics XXX Newly added diagnostic messages go under here, separated into L and L =head3 New Errors =over 4 =item * XXX L =back =head3 New Warnings =over 4 =item * XXX L =back =head2 Changes to Existing Diagnostics XXX Changes (i.e. rewording) of diagnostic messages go here =over 4 =item * XXX Describe change here =back =head1 Utility Changes XXX Changes to installed programs such as F and F go here. Most of these are built within the directory F. [ List utility changes as a =head2 entry for each utility and =item entries for each change Use F with program names to get proper documentation linking. ] =head2 F =over 4 =item * XXX =back =head1 Configuration and Compilation XXX Changes to F, F, F, and analogous tools go here. Any other changes to the Perl build process should be listed here. However, any platform-specific changes should be listed in the L section, instead. [ List changes as an =item entry ]. =over 4 =item * XXX =back =head1 Testing XXX Any significant changes to the testing of a freshly built perl should be listed here. Changes which create B files in F go here as do any large changes to the testing harness (e.g. when parallel testing was added). Changes to existing files in F aren't worth summarizing, although the bugs that they represent may be covered elsewhere. XXX If there were no significant test changes, say this: Tests were added and changed to reflect the other additions and changes in this release. XXX If instead there were significant changes, say this: Tests were added and changed to reflect the other additions and changes in this release. Furthermore, these significant changes were made: [ List each test improvement as an =item entry ] =over 4 =item * XXX =back =head1 Platform Support XXX Any changes to platform support should be listed in the sections below. [ Within the sections, list each platform as an =item entry with specific changes as paragraphs below it. ] =head2 New Platforms XXX List any platforms that this version of perl compiles on, that previous versions did not. These will either be enabled by new files in the F directories, or new subdirectories and F files at the top level of the source tree. =over 4 =item XXX-some-platform XXX =back =head2 Discontinued Platforms XXX List any platforms that this version of perl no longer compiles on. =over 4 =item XXX-some-platform XXX =back =head2 Platform-Specific Notes XXX List any changes for specific platforms. This could include configuration and compilation changes or changes in portability/compatibility. However, changes within modules for platforms should generally be listed in the L section. =over 4 =item XXX-some-platform XXX =back =head1 Internal Changes XXX Changes which affect the interface available to C code go here. Other significant internal changes for future core maintainers should be noted as well. [ List each change as an =item entry ] =over 4 =item * XXX =item * Mutex locks for C and C are removed The macros C and C macros are removed, along with their unlocking counterparts. These macros, though never documented, were intended to create thread safety when using their corresponding functions in a threaded-perl. But they didn't actually furnish that, so using them would give a false sense of security. Another thread simultaneously accessing the database could move the pointers, so these would act unpredictably. =item * New macros created for thread-safety in libc calls Many C library functions are not thread safe, but can be made so by using mutexes around them to lock out other threads from interrupting their execution. Many macros have now been created for this purpose. Guidance for using them, and the functions they protect are listed in L; their actual definitions are found in F. If you call a libc function, look in L to see if we have created locking macros for it. The macros are based on man pages (especially Linux ones), and our experience. We also know from experience that man pages can be wrong or incomplete, and the behavior of any given function may be platform dependent. Patches to update our knowledge base are welcome. More detail can be found in L. =item * During compiletime of a named subroutine, the name of the new sub currently being compiled is now accessible via C. =back =head1 Selected Bug Fixes XXX Important bug fixes in the core language are summarized here. Bug fixes in files in F and F are best summarized in L. XXX Include references to GitHub issues and PRs as: [GH #12345] and the release manager will later use a regex to expand these into links. [ List each fix as an =item entry ] =over 4 =item * XXX =back =head1 Known Problems XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any tests that had to be Ced for the release would be noted here. Unfixed platform specific bugs also go here. [ List each fix as an =item entry ] =over 4 =item * XXX =back =head1 Errata From Previous Releases =over 4 =item * XXX Add anything here that we forgot to add, or were mistaken about, in the F of a previous release. =back =head1 Obituary XXX If any significant core contributor or member of the CPAN community has died, add a short obituary here. =head1 Acknowledgements XXX Generate this with: perl Porting/acknowledgements.pl v5.45.1..HEAD =head1 Reporting Bugs If you find what you think is a bug, you might check the perl bug database at L. There may also be information at L, the Perl Home Page. If you believe you have an unreported bug, please open an issue at L. 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 L for details of how to report the issue. =head1 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 C program: perlthanks This will send an email to the Perl 5 Porters list with your show of thanks. =head1 SEE ALSO The F file for an explanation of how to view exhaustive details on what changed. The F file for how to build Perl. The F file for general stuff. The F and F files for copyright information. =cut