June 2026 - ruby-core - ml.ruby-lang.org

[ruby-core:120579] [Ruby master Feature#21020] Sync sig directory for prism of default gem.
by ksss (Yuki Kurihara) 08 Oct '26

08 Oct '26

Issue #21020 has been reported by ksss (Yuki Kurihara). ---------------------------------------- Feature #21020: Sync sig directory for prism of default gem. https://bugs.ruby-lang.org/issues/21020 * Author: ksss (Yuki Kurihara) * Status: Open ---------------------------------------- Currently, the type signatures (RBS) for the default gem is not available. **Prism** is the only default gem with type signatures, but this number is expected to increase in the future. As a first step to resolving this issue, I propose including the `sig` directory of Prism as a default gem in the synchronization process. PR: https://github.com/ruby/ruby/pull/12541 -- https://bugs.ruby-lang.org/

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[ruby-core:119757] [Ruby master Bug#20872] Undefined RUBY_API_VERSION_* macros used in <ruby/backward/cxxanyargs.hpp>
by hanazuki (Kasumi Hanazuki) 08 Oct '26

08 Oct '26

Issue #20872 has been reported by hanazuki (Kasumi Hanazuki). ---------------------------------------- Bug #20872: Undefined RUBY_API_VERSION_* macros used in <ruby/backward/cxxanyargs.hpp> https://bugs.ruby-lang.org/issues/20872 * Author: hanazuki (Kasumi Hanazuki) * Status: Open * ruby -v: ruby 3.4.0preview2 (2024-10-07 master 32c733f57b) +PRISM [x86_64-linux] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- I just noticed that C++ compilers warn for undefined RUBY_API_VERSION_MAJOR/RUBY_API_VERSION_MINOR macros in `<ruby/backward/cxxanyargs.hpp>` when preprocessing `<ruby.h>`. ``` % cat test.cpp #include <ruby.h> % clang++ -Wundef -I ~/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0 -I ~/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/x86_64-linux -c test.cpp -o /dev/null In file included from test.cpp:1: In file included from /home/kasumi/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/ruby.h:38: In file included from /home/kasumi/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/ruby/ruby.h:27: In file included from /home/kasumi/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/ruby/internal/anyargs.h:83: /home/kasumi/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/ruby/backward/cxxanyargs.hpp:540:6: warning: 'RUBY_API_VERSION_MAJOR' is not defined, evaluates to 0 [-Wundef] #if (RUBY_API_VERSION_MAJOR * 100 + RUBY_API_VERSION_MINOR) >= 301 ^ /home/kasumi/.rbenv/versions/3.4.0-preview2/include/ruby-3.4.0+0/ruby/backward/cxxanyargs.hpp:540:37: warning: 'RUBY_API_VERSION_MINOR' is not defined, evaluates to 0 [-Wundef] #if (RUBY_API_VERSION_MAJOR * 100 + RUBY_API_VERSION_MINOR) >= 301 ^ 2 warnings generated. ``` The offending code was introduced in commit:01825e8bffd. The accompanying code comment says a deprecation warning should be emitted for some use-cases (passing ANYARGS function pointers to `rb_define_method`-series functions) with Ruby 3.x, which looks not working as intended for the current Ruby versions. This seems effectively doing no harm but just disturbing for extension developers. -- https://bugs.ruby-lang.org/

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[ruby-core:125877] [Ruby Feature#22134] Faster rb_scan_args() for keyword args (optimization)
by luke-gru (Luke Gruber) 07 Oct '26

07 Oct '26

Issue #22134 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Feature #22134: Faster rb_scan_args() for keyword args (optimization) https://bugs.ruby-lang.org/issues/22134 * Author: luke-gru (Luke Gruber) * Status: Open ---------------------------------------- ## Motivation When using the `rb_scan_args()` API, often we want to find a value for a given keyword argument. In order to do this, we call `rb_scan_args()` like so: ```c VALUE str; VALUE kwargs; VALUE example; rb_scan_args(argc, argv, "1:", &str, &kwargs); // duplicates the kwargs hash in argv if (!NIL_P(kwargs)) rb_get_kwargs(kwargs, &id_example, 0, 1, &example); // mutates the duplicated kwargs hash to retrieve `example:` ``` This duplicates the keyword args hash given in `argv`. It would be nice to be able to grab a direct reference to the keyword hash and to have a variant of `rb_get_kwargs()` that didn't mutate the passed in hash. ## Proposal Add a new valid format character for `rb_scan_args()`: ```c VALUE str; VALUE kwargs; VALUE example; rb_scan_args(argc, argv, "1:^", &str, &kwargs); // access kwargs directly from argv if (!NIL_P(kwargs)) rb_get_kwargs_const(kwargs, &id_example, 0, 1, &example); // don't mutate the passed kwargs hash ``` This '^' character would only be valid after a ":'. I have a [pull request](https://github.com/ruby/ruby/pull/17558) available for anyone that is interested. Thank you! -- https://bugs.ruby-lang.org/

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[ruby-core:111146] [Ruby master Bug#19172] `ruby_thread_has_gvl_p` is innacurate sometimes -- document or change?
by ivoanjo (Ivo Anjo) 06 Oct '26

06 Oct '26

Issue #19172 has been reported by ivoanjo (Ivo Anjo). ---------------------------------------- Bug #19172: `ruby_thread_has_gvl_p` is innacurate sometimes -- document or change? https://bugs.ruby-lang.org/issues/19172 * Author: ivoanjo (Ivo Anjo) * Status: Open * Priority: Normal * ruby -v: (All Ruby versions) * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN ---------------------------------------- Howdy 👋! I work for Datadog [on the ddtrace gem](https://github.com/DataDog/dd-trace-rb) and I found a... sharp edge on the internal `ruby_thread_has_gvl_p` API. I am aware that `ruby_thread_has_gvl_p` is documented an experimental API that is exported as a symbol but not present on the VM include files. ### Background In the ddtrace profiling component, we setup a signal handler and then periodically send SIGPROF signals to try to interrupt the running Ruby thread (e.g. the thread that is holding the global VM lock or equivalent). In the signal handler, we need to perform some API calls which are not safe to do without the GVL. So we need to check if the signal handler got called in the thread that has the GVL. ### The issue ```ruby int ruby_thread_has_gvl_p(void) { rb_thread_t *th = ruby_thread_from_native(); if (th && th->blocking_region_buffer == 0) { return 1; } else { return 0; } } ``` In its current implementation, `ruby_thread_has_gvl_p` only checks if the thread has a `blocking_region_buffer` or not. Unfortunately, this means that when called from a thread that lost the GVL but not due to blocking (e.g. via `rb_thread_schedule()`), it can still claim that a thread is holding the GVL when that is not the case. I ran into this issue in https://github.com/DataDog/dd-trace-rb/pull/2415, and needed to find a workaround. ### Next steps Since this is an internal VM API, I'm not sure you'd want to change the current behavior, so I was thinking of perhaps two options: * Is it worth changing `ruby_thread_has_gvl_p` to be accurate in the case I've listed? * If not, would you accept a PR to document its current limitations, so that others don't run into the same issue I did? -- https://bugs.ruby-lang.org/

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[ruby-core:114332] [Ruby master Bug#19794] Ruby 3.2.2 fails to build on macOS Sonoma betas
by jhaungs (Jim Haungs) 02 Oct '26

02 Oct '26

Issue #19794 has been reported by jhaungs (Jim Haungs). ---------------------------------------- Bug #19794: Ruby 3.2.2 fails to build on macOS Sonoma betas https://bugs.ruby-lang.org/issues/19794 * Author: jhaungs (Jim Haungs) * Status: Open * Priority: Normal * ruby -v: 3.2.2 * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- With Big Sur, Apple deprecated putting dylibs in /usr/local/lib. In Sonoma (beta 4), this directory has disappeared completely. However, ruby's configure script depends on its existence. So, virtually every ruby installer (RVM, rbenv, asdf, ruby-build, and even building from source tarball) fails. When building ruby 3.2.2 from source, the configure step outputs the irritatingly useless "something wrong with LDFLAGS" error message and fails to build. The solution was to `cd /usr/local; sudo mkdir lib` to create the missing lib directory under /usr/local. It would be nice to remove this dependency from the configure script. -- https://bugs.ruby-lang.org/

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[ruby-core:111740] [Ruby master Bug#19325] Windows support lacking.
by dsisnero (Dominic Sisneros) 29 Sep '26

29 Sep '26

Issue #19325 has been reported by dsisnero (Dominic Sisneros). ---------------------------------------- Bug #19325: Windows support lacking. https://bugs.ruby-lang.org/issues/19325 * Author: dsisnero (Dominic Sisneros) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- Ruby's support on windows has always been second class. With some of the recent decisions, windows support is falling even more behind. Recent developments in mjit and yjit that exclude windows are two glaring issues that should be corrected. Googling 'percent of windows vs other operating systems' and it shows windows has a share of 76%. Ceding that users to python and other programming languages has to be one of the reasons python continues get more market share from ruby. With rust having first class windows support and threading support, is there a reason why yjit is not able to work on windows? Also, windows compiler support has matured enough and vcpkg support has evolved enough that it seems it should be possible to finally get a ruby version without having to use msys2. Even Crystal language has a version that runs on windows without needing msys2. -- https://bugs.ruby-lang.org/

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[ruby-core:125612] [Ruby Bug#22092] `Array#sum` takes slow path, does not perform compensated summation of Float elements when init argument is a Float
by georgeclaghorn (George Claghorn) 25 Sep '26

25 Sep '26

Issue #22092 has been reported by georgeclaghorn (George Claghorn). ---------------------------------------- Bug #22092: `Array#sum` takes slow path, does not perform compensated summation of Float elements when init argument is a Float https://bugs.ruby-lang.org/issues/22092 * Author: georgeclaghorn (George Claghorn) * Status: Open * ruby -v: ruby 4.0.1 (2026-01-13 revision e04267a14b) +PRISM [arm64-darwin24] * Backport: 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- ``` % time ruby -e 'puts Array.new(1_000_000_000, 0.1).sum' 100000000.0 ruby -e 'puts Array.new(1_000_000_000, 0.1).sum' 2.67s user 2.02s system 71% cpu 6.577 total % time ruby -e 'puts Array.new(1_000_000_000, 0.1).sum(0.0)' 99999998.74541782 ruby -e 'puts Array.new(1_000_000_000, 0.1).sum(0.0)' 22.72s user 1.80s system 96% cpu 25.332 total ``` Both the fast path and compensated summation are undocumented implementation details as far as I know, but this appears to be a possible oversight. -- https://bugs.ruby-lang.org/

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[ruby-core:125491] [Ruby Feature#22068] Adding post-quantum cryptography (PQC) support across Ruby standard libraries
by jaruga (Jun Aruga) 21 Sep '26

21 Sep '26

Issue #22068 has been reported by jaruga (Jun Aruga). ---------------------------------------- Feature #22068: Adding post-quantum cryptography (PQC) support across Ruby standard libraries https://bugs.ruby-lang.org/issues/22068 * Author: jaruga (Jun Aruga) * Status: Open ---------------------------------------- ## Summary and motivation Post-quantum cryptography (PQC) means cryptography algorithm which people can safely use after (post) quantum computing is practically used in the future. By using the quantum computing which is much more powerful than the current computing, it can be possible to crack the current non-PQC algorithms. The goal of this ticket is to make Ruby (including libraries: default gems + bundle gems) work in the environment where only post-quantum cryptography (PQC)-supported algorithms are enabled, and other cryptography algorithms such as RSA are disabled. PQC-supported algorithms are only ML-DSA, ML-KEM and SLH-DSA for now. ML-DSA is used for signature (certification), and ML-KEM is used for connection. As I heard from my colleagues working for OpenSSL, that SLH-DSA is not ready to be used, we can ignore SLH-DSA for now. Ruby OpenSSL (ruby/openssl) already supports PQC by the ticket [ruby/openssl#894][ruby-openssl-pqc-issue]. And there are some works are needed for other standard libraries using Ruby OpenSSL in Ruby to support PQC. I cite the following text from the [NIST][nist-wikipedia]'s [PQC document][nist-pqc]. NIST is an organization deciding cryptography specifications in my understanding. > Some engineers even predict that within the next twenty or so years sufficiently large quantum computers will be built to break essentially all public key schemes currently in use. Historically, it has taken almost two decades to deploy our modern public key cryptography infrastructure. Therefore, regardless of whether we can estimate the exact time of the arrival of the quantum computing era, we must begin now to prepare our information security systems to be able to resist quantum computing. I also cite the following text from DigiCert, a security company's blog. ([link][digicert-blog-google-mtc]) > Gartner predicts that by 2029, conventional asymmetric cryptography like RSA and ECC will be unsafe for protecting sensitive data due to “harvest-now, decrypt-later" threats—even before a quantum break occurs. So, it's better to prepare PQC support now. As an example of the actual movement European Commission is trying to migrate from non-PQC to PQC.([link][ec-pqc]) ## Proof of concept I manage my proof-of-concept scripts on my [junaruga/ruby-pqc-test] repository. For now, there are only some scripts to test RubyGems and Bundler in PQC use cases. ## Tasks I checked ruby/ruby including default gems and bundled gems at the master branch commit `93f1010f70a3ac924c3b37e4ae82cf1a669fcbf0` which was the latest at that time. While ruby/ruby original code doesn't have PQC logic, the following libraries that have the own upstream project need to be modified to support PQC use cases in my investigation. And I am motivated to work on these tasks, adding the PQC features and/or tests. I will open the issue ticket for each upstream project ruby/* one by one. * [ruby/rubygems](https://github.com/ruby/rubygems) - Add PQC features * [ruby/rubygems bundler](https://github.com/ruby/rubygems/tree/master/bundler) - Add PQC features * [ruby/net-http](https://github.com/ruby/net-http) - default gem - Update code comments and add PQC tests * [ruby/open-uri](https://github.com/ruby/open-uri) - default gem - Add PQC tests * [ruby/spec](https://github.com/ruby/spec) - spec/ - Add PQC tests * [ruby/drb](https://github.com/ruby/drb): bundled gem - Add PQC features * [ruby/rbs](https://github.com/ruby/rbs): bundled gem - Not sure. There is `stdlib/openssl/0/openssl.rbs`. Note I used the following [ripgrep]'s `rg` command (an enhanced `grep` command) to check the affected files by PQC. ``` $ rg "require +['\"]openssl['\"]|OpenSSL" --type ruby ``` Please let me know what you think. [openssl-35-release]: https://openssl-library.org/post/2025-04-08-openssl-35-final-release/ [ruby-openssl-pqc-issue]: https://github.com/ruby/openssl/issues/894 [nist-wikipedia]: https://en.wikipedia.org/wiki/National_Institute_of_Standards_and_Technology [nist-pqc]: https://csrc.nist.gov/projects/post-quantum-cryptography [ec-pqc]: https://digital-strategy.ec.europa.eu/en/library/coordinated-implementation… [digicert-blog-google-mtc]: https://www.digicert.com/blog/google-merkle-tree-certificates [junaruga/ruby-pqc-test]: https://github.com/junaruga/ruby-pqc-test [ripgrep]: https://github.com/BurntSushi/ripgrep -- https://bugs.ruby-lang.org/

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[ruby-core:124714] [Ruby Bug#21870] Regexp: Warnings when using multiple non-overlapping \p{...} classes
by jneen (Jeanine Adkisson) 21 Sep '26

21 Sep '26

Issue #21870 has been reported by jneen (Jeanine Adkisson). ---------------------------------------- Bug #21870: Regexp: Warnings when using multiple non-overlapping \p{...} classes https://bugs.ruby-lang.org/issues/21870 * Author: jneen (Jeanine Adkisson) * Status: Open * ruby -v: 4.0.0, 4.0.1, earlier versions to a lesser extent * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- ```ruby $VERBOSE = true # warning: character class has duplicated range: /[\p{Word}\p{S}]/ regex = /[\p{Word}\p{S}]/ ``` As far as I can tell this is a perfectly valid and non-overlapping set of unicode properties, but I am still being spammed with warnings. Using `/(\p{Word}|\p{S})/` is kind of a workaround, but it is slower. -- https://bugs.ruby-lang.org/

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[ruby-core:123881] [Ruby Bug#21703] RUBY_CRASH_REPORT does not work when shelling out in some cases
by peterzhu2118 (Peter Zhu) 17 Sep '26

17 Sep '26

Issue #21703 has been reported by peterzhu2118 (Peter Zhu). ---------------------------------------- Bug #21703: RUBY_CRASH_REPORT does not work when shelling out in some cases https://bugs.ruby-lang.org/issues/21703 * Author: peterzhu2118 (Peter Zhu) * Status: Open * Backport: 3.2: DONTNEED, 3.3: REQUIRED, 3.4: REQUIRED ---------------------------------------- GitHub PR: https://github.com/ruby/ruby/pull/15292 RUBY_CRASH_REPORT does not work in some cases when shelling out on Linux. For example, given the following shell script dump.sh: ```sh #!/usr/bin/env bash cat > /tmp/crash ``` And we see it fails like this: ``` $ RUBY_CRASH_REPORT="|dump.sh" ruby -rfiddle -e "Fiddle::Pointer.new(1, 10)[0]" cat: -: Resource temporarily unavailable ``` -- https://bugs.ruby-lang.org/

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