October 2025 - ruby-core - ml.ruby-lang.org

[ruby-core:121389] [Ruby Bug#21187] Strings concatenated with `\` getting frozen with literal hashes (PRISM only)
by LocoDelAssembly 08 Dec '25

08 Dec '25

Issue #21187 has been reported by LocoDelAssembly (Hernán Pereira). ---------------------------------------- Bug #21187: Strings concatenated with `\` getting frozen with literal hashes (PRISM only) https://bugs.ruby-lang.org/issues/21187 * Author: LocoDelAssembly (Hernán Pereira) * Status: Open * ruby -v: ruby 3.4.2 (2025-02-15 revision d2930f8e7a) +PRISM [x86_64-linux] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- When the first elements of a literal hash are strings that are concatenated with `\`, those elements are flagged with `PM_NODE_FLAG_STATIC_LITERAL` and a special optimization that I believe was introduced in https://github.com/ruby/ruby/commit/8080de04be8e99e71309745822a9d436cc4ae37c causes the strings to be frozen. Reproduction === test.rb ``` a = { a: 'one' \ 'two', b: 'three' \ 'four', c: 'five', d: 'six' \ 'seven' } b = { a: 'one', b: 'two' \ 'three' } puts "a = #{a.map { |k,v| {k => v.frozen?} }}" puts "b = #{b.map { |k,v| {k => v.frozen?} }}" ``` With prism: ``` $ ruby test.rb a = [{a: true}, {b: true}, {c: false}, {d: false}] b = [{a: false}, {b: false}] ``` With parse.y: ``` $ ruby --parser=parse.y test.rb a = [{a: false}, {b: false}, {c: false}, {d: false}] b = [{a: false}, {b: false}] ``` (Notice `b` hash is unaffected in both parsers) Not sure if this is just part of undefined behavior or this is indeed a bug. Assigning a string concatenated with `\` to a variable doesn't make it frozen, to the best of my knowledge this seems to be hash-specific. -- https://bugs.ruby-lang.org/

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[ruby-core:123582] [Ruby Bug#21655] segfault when building 3.3.10, regression from 3.3.9
by kurly (Greg Kubaryk) 08 Dec '25

08 Dec '25

Issue #21655 has been reported by kurly (Greg Kubaryk). ---------------------------------------- Bug #21655: segfault when building 3.3.10, regression from 3.3.9 https://bugs.ruby-lang.org/issues/21655 * Author: kurly (Greg Kubaryk) * Status: Open * ruby -v: ruby 3.3.10 (2025-10-23 revision 343ea05002) [x86_64-linux] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- ref downstream bug https://bugs.gentoo.org/965095 - reporting upstream because I was able to reproduce the problem from ruby-3.3.10.tar.xz manually build log excerpt; the rest will be provided as an attachment gcc -O2 -pipe -march=amdfam10 -L. -fstack-protector-strong -rdynamic -Wl,-export-dynamic -fstack-protector-strong -pie main.o dmydln.o miniinit.o dmyext.o array.o ast.o bignum.o class.o compar.o compile.o complex.o cont.o debug.o debug_counter.o dir.o dln_find.o encoding.o enum.o enumerator.o error.o eval.o file.o gc.o hash.o inits.o io.o io_buffer.o iseq.o load.o marshal.o math.o memory_view.o rjit.o rjit_c.o node.o node_dump.o numeric.o object.o pack.o parse.o parser_st.o proc.o process.o ractor.o random.o range.o rational.o re.o regcomp.o regenc.o regerror.o regexec.o regparse.o regsyntax.o ruby.o ruby_parser.o scheduler.o shape.o signal.o sprintf.o st.o strftime.o string.o struct.o symbol.o thread.o time.o transcode.o util.o variable.o version.o vm.o vm_backtrace.o vm_dump.o vm_sync.o vm_trace.o weakmap.o prism/api_node.o prism/api_pack.o prism/diagnostic.o prism/encoding.o prism/extension.o prism/node.o prism/options.o prism/pack.o prism/prettyprint.o prism/regexp.o prism/serialize.o prism/token_type.o prism/util/pm_buffer.o prism/util/pm_char.o prism/util/pm_constant_pool.o prism/util/pm_list.o prism/util/pm_memchr.o prism/util/pm_newline_list.o prism/util/pm_state_stack.o prism/util/pm_string.o prism/util/pm_string_list.o prism/util/pm_strncasecmp.o prism/util/pm_strpbrk.o prism/prism.o prism_init.o yjit.o yjit/target/release/libyjit.o coroutine/amd64/Context.o enc/ascii.o enc/us_ascii.o enc/unicode.o enc/utf_8.o enc/trans/newline.o setproctitle.o addr2line.o -lz -lrt -lrt -lgmp -ldl -lcrypt -lm -lpthread -o miniruby : ./miniruby -I./lib -I. -I.ext/common ./tool/generic_erb.rb -o builtin_binary.inc \ ./template/builtin_binary.inc.tmpl make: *** [uncommon.mk:1316: builtin_binary.inc] Segmentation fault (core dumped) ---Files-------------------------------- buildlog (76.5 KB) -- https://bugs.ruby-lang.org/

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[ruby-core:121629] [Ruby Bug#21265] Crash when proc from Symbol#to_proc called outside refinement scope
by alanwu (Alan Wu) 08 Dec '25

08 Dec '25

Issue #21265 has been reported by alanwu (Alan Wu). ---------------------------------------- Bug #21265: Crash when proc from Symbol#to_proc called outside refinement scope https://bugs.ruby-lang.org/issues/21265 * Author: alanwu (Alan Wu) * Status: Open * ruby -v: ruby 3.4.2 and trunk * Backport: 3.2: DONTNEED, 3.3: DONTNEED, 3.4: REQUIRED ---------------------------------------- ```ruby class RefinedScope using(Module.new { refine(Kernel) { def itself = 0 } }) ITSELF = :itself.to_proc end RefinedScope::ITSELF[0] ``` ``` ../vm_method.c:1371: Assertion Failed: prepare_callable_method_entry:RB_TYPE_2_P(defined_class, RUBY_T_ICLASS, RUBY_T_MODULE): defined_class: T_FALSE ``` Or SEGV without `-DRUBY_DEBUG`. -- https://bugs.ruby-lang.org/

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[ruby-core:121142] [Ruby master Misc#21154] Document or change Module#autoload?
by fxn (Xavier Noria) 07 Dec '25

07 Dec '25

Issue #21154 has been reported by fxn (Xavier Noria). ---------------------------------------- Misc #21154: Document or change Module#autoload? https://bugs.ruby-lang.org/issues/21154 * Author: fxn (Xavier Noria) * Status: Open ---------------------------------------- The documentation of `Module#autoload?` says > Returns filename to be loaded if name is registered as autoload in the namespace of mod or one of its ancestors. Cool, but in the following snippet ```ruby autoload :Foo, 'foo' autoload?(:Foo) ``` the second line could evaluate to `nil`, and this does not seem to agree. I just registered an autoload, therefore (according to the documentation) I should get "foo" back in line 2. I'd like to ask for clarification from the Ruby team: 1. Is the documentation complete? Should that second line always return "foo"? 2. If the answer is no, which is the logic missing in the docs? Thank you! -- https://bugs.ruby-lang.org/

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[ruby-core:121791] [Ruby Bug#21298] `ObjectSpace.allocation_class_path` returns inconsistent results depending on `TracePoint` state
by mame (Yusuke Endoh) 05 Dec '25

05 Dec '25

Issue #21298 has been reported by mame (Yusuke Endoh). ---------------------------------------- Bug #21298: `ObjectSpace.allocation_class_path` returns inconsistent results depending on `TracePoint` state https://bugs.ruby-lang.org/issues/21298 * Author: mame (Yusuke Endoh) * Status: Open * Assignee: tenderlovemaking (Aaron Patterson) * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- `ObjectSpace.allocation_class_path` is an API that returns the class of `self` in the context where an object was allocated. However, due to recent optimizations in `Class#new` (#21254), the return value now changes depending on whether `TracePoint` is enabled. ```ruby require "objspace" class Foo def test obj = Object.new ObjectSpace.allocation_class_path(obj) end end ObjectSpace.trace_object_allocations_start p Foo.new.test #=> 3.4.2: "Class", master: "Foo" ``` Previously, this returned `"Class"` (from the `Class#new` call frame), but in the master branch, the result is now `"Foo"` because that frame is gone. I am ok for the incompatibility itself because I find the new behavior more intuitive and useful. However, there's an inconsistency: the optimization is disabled when `TracePoint` is enabled, causing the result to revert to the old behavior. ```ruby p Foo.new.test #=> master: "Foo" TracePoint.new {}.enable do p Foo.new.test #=> master: "Class", expected: "Foo" end ``` This makes behavior dependent on whether `TracePoint` is enabled, which can lead to confusion. @ko1 @tenderlovemaking Can we make `ObjectSpace.allocation_class_path` consistently return the class from the `.new` call context, regardless of the `TracePoint` state? --- I am facing a failure of the following test when code coverage (which uses `TracePoint`) is enabled: https://github.com/ruby/ruby/blob/e8ad728209ee22136e61054fea74096b49088b8a/… As a short-term workaround, I'm considering commenting out this test. -- https://bugs.ruby-lang.org/

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[ruby-core:112326] [Ruby master Feature#19430] Contribution wanted: DNS lookup by c-ares library
by mame (Yusuke Endoh) 05 Dec '25

05 Dec '25

Issue #19430 has been reported by mame (Yusuke Endoh). ---------------------------------------- Feature #19430: Contribution wanted: DNS lookup by c-ares library https://bugs.ruby-lang.org/issues/19430 * Author: mame (Yusuke Endoh) * Status: Open * Priority: Normal ---------------------------------------- ## Problem At the present time, Ruby uses `getaddrinfo(3)` to resolve names. Because this function is synchronous, we cannot interrupt the thread performing name resolution until the DNS server returns a response. We can see this behavior by setting blackhole.webpagetest.org (72.66.115.13) as a DNS server, which swallows all packets, and resolving any name: ``` # cat /etc/resolv.conf nameserver 72.66.115.13 # ./local/bin/ruby -rsocket -e 'Addrinfo.getaddrinfo("www.ruby-lang.org", 80)' ^C^C^C^C ``` As we see, Ctrl+C does not stop ruby. The current workaround that users can take is to do name resolution in a Ruby thread. ```ruby Thread.new { Addrinfo.getaddrinfo("www.ruby-lang.org", 80) }.value ``` The thread that calls this code is interruptible. (Note that the newly created thread itself will be stuck until the DNS lookup exceeds the time out.) ## Proposal We can solve this problem by using c-ares, which is an asynchronous name resolver, as a backend of `Addrinfo.getaddrinfo`, etc. (@sorah told me about this library, thanks!) https://c-ares.org/ I have created a PoC patch. https://github.com/mame/ruby/commit/547806146993bbc25984011d423dcc0f913b211c By applying this patch, we can interrupt `Addrinfo.getaddrinfo` by Ctrl+C. ``` # cat /etc/resolv.conf nameserver 72.66.115.13 # ./local/bin/ruby -rsocket -e 'Addrinfo.getaddrinfo("www.ruby-lang.org", 80)' ^C-e:1:in `getaddrinfo': Interrupt from -e:1:in `<main>' ``` ## Discussion ### About c-ares According to the site of c-ares, some major tools including libcurl, Wireshark, and Apache Arrow are already using c-ares. In the language interpreter, node.js seems to be using c-ares. I am honestly not sure about the compatibility of c-ares with `getaddrinfo(3)`. I guess there is no major incompatibility because I have not experienced any name resolution problem of curl. @akr (who is the author and maintainer of Ruby's socket library) suggested to check if OS-specific name resolution, e.g., WINS on Windows, NIS on Solaris, etc., is supported. He also said that it may be acceptable even if they are not supported. Whether to bundle c-ares source code with ruby would require further discussion. If this proposal is accepted, then c-ares will become a de facto essential dependency for practical use, like gmp, in my opinion. Incidentally, node.js bundles c-ares: https://github.com/nodejs/node/tree/main/deps/cares ### Alternative approaches Recent glibc provides `getaddrinfo_a(3)` which performs asynchronous name resolution. However, this function has a fatal problem of being incompatible with `fork(2)`, which is heavily used in the Ruby ecosystem. In fact, the attempt to use `getaddrinfo_a(3)` (#17134) has been revert because it fails rails tests. (#17220) Another alternative is to have a worker pthread inside Ruby that calls getaddrinfo(3). Instead of calling getaddrinfo(3) directly, `Addrinfo.getaddrinfo` would ask the worker to resolve a name and wait for a response. This method should be able to implement cancellation. (Simply put, this means reimplementation of getaddrinfo_a(3) on our own, taking into account of `fork(2).) This has the advantages: not adding dependencies on external libraries and not having compatibility issues with `getaddrinfo(3)`. However, it is considerably more difficult to implement and maintain. An internal pthread may have a non-trivial impact on the execution efficiency and memory usage. Also, we may need to implement a mechanism to dynamically change the number of workers depending on the load. It would be ideal if we could try and evaluate both approaches. But my current impression is that using c-ares is the quickest and best compromise. ## Contribution wanted I have made it up to the PoC, but don't have much time to complete this. @naruse suggested me to create a ticket asking for contributions. Is anyone interested in this? * This patch changes `rsock_getaddrinfo` to accept a timeout argument. There are several places where Qnil is passed as a timeout (where I add `// TODO` in the PoC). We need to consider what timeout we should pass. * This cares only `getaddrinfo`, but we also need to care `getnameinfo` (and something else if any). There may be some issues I'm not aware of. * I have not yet tested this PoC seriously. It would be great if we could evaluate it with some real apps. Also, it would be great to hear from someone who knows more about c-ares. -- https://bugs.ruby-lang.org/

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[ruby-core:123504] [Ruby Bug#21645] Can't `require "resolve"` on Windows under Bundler without warnings
by Earlopain (Earlopain _) 02 Dec '25

02 Dec '25

Issue #21645 has been reported by Earlopain (Earlopain _). ---------------------------------------- Bug #21645: Can't `require "resolve"` on Windows under Bundler without warnings https://bugs.ruby-lang.org/issues/21645 * Author: Earlopain (Earlopain _) * Status: Open * ruby -v: ruby 3.5.0dev (2025-10-19 master 957c832db1) +PRISM [x64-mingw-ucrt] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- `prism` had disabled some workflows for ruby-head on windows because of the extraction from fiddle to being a bundled gem. I attempted to renable them now, but it is still an issue: https://github.com/ruby/prism/pull/3687 During `bundle install`, the `mini_portile2` gem (to build `nokogiri`) ends up requiring `net/http`, which in turn requires `resolv`. On windows, `resolv` requires `win32/resolv` here: https://github.com/ruby/ruby/blob/6eb75f6c36288cdd7522f27ad18608d13031f2b8/…. `win32-registry` depends on `fiddle`, and so under bundler it fails with the following: ``` D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/specification.rb:1419:in 'block in Gem::Specification#activate_dependencies': Could not find 'fiddle' (~> 1.0) among 61 total gem(s) (Gem::MissingSpecError) Checked in 'GEM_PATH=D:/a/prism/prism/vendor/bundle/ruby/3.5.0+4' at: D:/rubyinstaller-head-x64/lib/ruby/gems/3.5.0+4/specifications/win32-registry-0.1.0.gemspec, execute `gem env` for more information from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/specification.rb:1405:in 'Array#each' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/specification.rb:1405:in 'Gem::Specification#activate_dependencies' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/specification.rb:1387:in 'Gem::Specification#activate' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/core_ext/kernel_gem.rb:62:in 'block in Kernel#gem' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/core_ext/kernel_gem.rb:62:in 'Thread::Mutex#synchronize' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/rubygems/core_ext/kernel_gem.rb:62:in 'Kernel#gem' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/resolv.rb:1026:in 'Kernel#require' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/resolv.rb:1026:in 'Resolv::DNS::Config.default_config_hash' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/resolv.rb:95:in 'Resolv#initialize' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/resolv.rb:3469:in '<class:Resolv>' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/resolv.rb:35:in '<top (required)>' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/net/http.rb:25:in 'Kernel#require' from D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/net/http.rb:25:in '<top (required)>' from D:/a/prism/prism/vendor/bundle/ruby/3.5.0+4/gems/mini_portile2-2.8.9/lib/mini_portile2/mini_portile.rb:2:in 'Kernel#require' ``` I have tried to make a small reproduction by simply running `bundle exec ruby -rresolv` but there I just get a warning: ``` D:/rubyinstaller-head-x64/lib/ruby/3.5.0+4/win32/registry.rb:2: warning: fiddle/import is found in fiddle, which is not part of the default gems since Ruby 3.5.0. You can add fiddle to your Gemfile or gemspec to fix this error. ``` I am not sure why that is. I feel like it should at the very least raise. But I don't have a windows machine to investigate this. Here is a github action run that shows this: https://github.com/Earlopain/test/actions/runs/18653590178/job/53177107372 There is also a github issue: https://github.com/ruby/win32-registry/issues/11 -- https://bugs.ruby-lang.org/

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[ruby-core:117618] [Ruby master Feature#20437] Could be the licensing conditions be made less ambiguous?
by vo.x (Vit Ondruch) 01 Dec '25

01 Dec '25

Issue #20437 has been reported by vo.x (Vit Ondruch). ---------------------------------------- Feature #20437: Could be the licensing conditions be made less ambiguous? https://bugs.ruby-lang.org/issues/20437 * Author: vo.x (Vit Ondruch) * Status: Open ---------------------------------------- # Current state The current [COPYING](https://github.com/ruby/ruby/blob/6cfd929034f1fe3d93160365505a8b88… file says the following: ~~~ Ruby is copyrighted free software by Yukihiro Matsumoto <matz(a)netlab.jp>. You can redistribute it and/or modify it under either the terms of the 2-clause BSDL (see the file BSDL), or the conditions below: 1. You may make and give away verbatim copies of the source form of the ... snip ... ~~~ And this is quite ambiguous. Let me show a few examples: # Ambiguous examples ## lib/net/protocol.rb https://github.com/ruby/ruby/blob/6cfd929034f1fe3d93160365505a8b88bef56159/… ~~~ # This program is free software. You can re-distribute and/or # modify this program under the same terms as Ruby itself, # Ruby Distribute License or GNU General Public License. ~~~ So what is the license? Is it 2-clause BSDL + Ruby + GPL? Or is is just Ruby + GPL but not 2-clause BSDL? ## Racc https://github.com/ruby/racc/blob/d52fb64d166046bfde81e6e9c424fcd884ebcabf/… ~~~ Racc is distributed under the same terms of ruby. (see the file COPYING). ~~~ where the [COPYING](https://github.com/ruby/racc/blob/d52fb64d166046bfde81e6e9c424fcd8… contains just 2-clause BSDL. Not even mentioning that Ruby used to be GPLv2 licensed: https://github.com/ruby/racc/commit/cc7fe952a6b1fc2ef43477674fa13f2d9d99e818 ## Rubygems https://github.com/rubygems/rubygems/blob/master/LICENSE.txt The license is obviously modeled after Ruby COPYING file, but if it could say "licensed under MIT or Ruby", it would be much better. ## Gettext https://github.com/ruby-gettext/gettext/blob/8d84132efd888e68fffbce41331645… The license note is so old that it is not obvious what that means and what was the intention. Did the Ruby relicensing from "GPLv2 or Ruby" to "GPLv2 or BSD" influenced this project? ## SPDX https://spdx.org/licenses/Ruby.html It quotes just the "conditions below" as a Ruby license, while referring to [Ruby license file](https://www.ruby-lang.org/en/about/license.txt) mentioning also 2-clause BSDL # Proposal To me it seems that the whole world recognizes "Ruby" license, except Ruby. Therefore I think it would be nice if Ruby project recognized the "Ruby" license. There are two possibilities I can think of: ## Refer the license by name ~~~diff $ git diff diff --git a/COPYING b/COPYING index 48e5a96de7..a2d179a8a9 100644 --- a/COPYING +++ b/COPYING @@ -1,6 +1,6 @@ Ruby is copyrighted free software by Yukihiro Matsumoto <matz(a)netlab.jp>. You can redistribute it and/or modify it under either the terms of the -2-clause BSDL (see the file BSDL), or the conditions below: +2-clause BSDL (see the file BSDL), or the conditions of the Ruby license below: 1. You may make and give away verbatim copies of the source form of the software without restriction, provided that you duplicate all of the ~~~ ## Extract the "conditions below" into "Ruby" license file The "conditions below" text could be extracted into separate file (e.g. "RUBY_LICENSE") and the "COPYING" file rephrased to say: ~~~ Ruby is copyrighted free software by Yukihiro Matsumoto <matz(a)netlab.jp>. You can redistribute it and/or modify it under either the terms of the 2-clause BSDL (see the file BSDL), or Ruby license (see the file RUBY_LICENSE) ~~~ -- https://bugs.ruby-lang.org/

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[ruby-core:123569] [Ruby Bug#21652] Marshal#dump documentation out-of-date/unclear regarding Data class
by ryannevell (Ryan Nevell) 28 Nov '25

28 Nov '25

Issue #21652 has been reported by ryannevell (Ryan Nevell). ---------------------------------------- Bug #21652: Marshal#dump documentation out-of-date/unclear regarding Data class https://bugs.ruby-lang.org/issues/21652 * Author: ryannevell (Ryan Nevell) * Status: Open * ruby -v: ruby 3.2.2 (2023-03-30 revision e51014f9c0) [x86_64-linux] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- With the introduction of the `Data` class in Ruby 3.2, the `Marshal#dump` documentation is confusing since it claims that "Marshal can’t dump ... an instance of ... Data". It is even cross-linked to the new `Data` class. However, and thankfully, `Marshal#dump` does not have any issues serializing instances of `Data` or objects of the defined `Data` types. This message predates the introduction of the `Data` class, and likely refers to wrapped C data (`T_DATA`), instead. -- https://bugs.ruby-lang.org/

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[ruby-core:122900] [Ruby Bug#21529] Deprecate the /o modifier and warn against using it
by jpcamara (JP Camara) 28 Nov '25

28 Nov '25

Issue #21529 has been reported by jpcamara (JP Camara). ---------------------------------------- Bug #21529: Deprecate the /o modifier and warn against using it https://bugs.ruby-lang.org/issues/21529 * Author: jpcamara (JP Camara) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- I recently ran into a bug in some code because it was using the /o modifier as an optimization, not realizing it created a permanent, immutable value after the first time it gets evaluated. I dug into how the modifier works in CRuby and the history of it here: https://jpcamara.com/2025/08/02/the-o-in-ruby-regex.html. The feature seems like a total footgun with almost no upside. If I run a benchmark between a local regex, and a regex cached by /o, there is no real difference. ```rb require "benchmark" def letters "A-Za-z" end words = %w[the quick brown fox jumped over the lazy dog] Benchmark.bm do |bm| bm.report("without /o:") do regex = /\A[A-Za-z]+\z/ words.each do |word| word.match(regex) end end bm.report("with /o: ") do words.each do |word| word.match(/\A[#{letters}]+\z/o) end end end ``` Most of the time I found that "without /o" actually came out ahead. ``` user system total real without /o: 0.000019 0.000003 0.000022 ( 0.000014) with /o: 0.000020 0.000001 0.000021 ( 0.000020) ``` I'd like to deprecate the feature and update the docs to warn against using it. I'd be happy to submit a PR doing that. Thanks! -- https://bugs.ruby-lang.org/

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