Ruby 3.4.0 rc1 Released

Posted by naruse on 12 Dec 2024

We are pleased to announce the release of Ruby 3.4.0-rc1.

Prism

Switch the default parser from parse.y to Prism. [Feature #20564]

Modular GC

  • Alternative garbage collector (GC) implementations can be loaded dynamically through the modular garbage collector feature. To enable this feature, configure Ruby with --with-modular-gc at build time. GC libraries can be loaded at runtime using the environment variable RUBY_GC_LIBRARY. [Feature #20351]

  • Ruby’s built-in garbage collector has been split into a separate file at gc/default/default.c and interacts with Ruby using an API defined in gc/gc_impl.h. The built-in garbage collector can now also be built as a library using make modular-gc MODULAR_GC=default and enabled using the environment variable RUBY_GC_LIBRARY=default. [Feature #20470]

  • An experimental GC library is provided based on MMTk. This GC library can be built using make modular-gc MODULAR_GC=mmtk and enabled using the environment variable RUBY_GC_LIBRARY=mmtk. This requires the Rust toolchain on the build machine. [Feature #20860]

Language changes

  • String literals in files without a frozen_string_literal comment now emit a deprecation warning when they are mutated. These warnings can be enabled with -W:deprecated or by setting Warning[:deprecated] = true. To disable this change, you can run Ruby with the --disable-frozen-string-literal command line argument. [Feature #20205]

  • it is added to reference a block parameter. [Feature #18980]

  • Keyword splatting nil when calling methods is now supported. **nil is treated similarly to **{}, passing no keywords, and not calling any conversion methods. [Bug #20064]

  • Block passing is no longer allowed in index. [Bug #19918]

  • Keyword arguments are no longer allowed in index. [Bug #20218]

YJIT

TL;DR:

  • Better performance on most benchmarks on both x86-64 and arm64 platforms.
  • Reduced memory usage of compilation metadata
  • Multiple bug fixes. YJIT is now even more robust and better tested.

New features:

  • Add unified memory limit via --yjit-mem-size command-line option (default 128MiB) which tracks total YJIT memory usage and is more intuitive than the old --yjit-exec-mem-size.
  • More statistics now always available via RubyVM::YJIT.runtime_stats
  • Add compilation log to track what gets compiled via --yjit-log
    • Tail of the log also available at run-time via RubyVM::YJIT.log
  • Add support for shareable consts in multi-ractor mode
  • Can now trace counted exits with --yjit-trace-exits=COUNTER

New optimizations:

  • Compressed context reduces memory needed to store YJIT metadata
  • Improved allocator with ability to allocate registers for local variables
  • When YJIT is enabled, use more Core primitives written in Ruby:
    • Array#each, Array#select, Array#map rewritten in Ruby for better performance [Feature #20182].
  • Ability to inline small/trivial methods such as:
    • Empty methods
    • Methods returning a constant
    • Methods returning self
    • Methods directly returning an argument
  • Specialized codegen for many more runtime methods
  • Optimize String#getbyte, String#setbyte and other string methods
  • Optimize bitwise operations to speed up low-level bit/byte manipulation
  • Various other incremental optimizations

Core classes updates

Note: We’re only listing outstanding class updates.

  • Exception

    • Exception#set_backtrace now accepts an array of Thread::Backtrace::Location. Kernel#raise, Thread#raise and Fiber#raise also accept this new format. [Feature #13557]

  • Range

    • Range#size now raises TypeError if the range is not iterable. [Misc #18984]

Compatibility issues

Note: Excluding feature bug fixes.

  • Error messages and backtrace displays have been changed.
    • Use a single quote instead of a backtick as a opening quote. [Feature #16495]
    • Display a class name before a method name (only when the class has a permanent name). [Feature #19117]
    • Kernel#caller, Thread::Backtrace::Location’s methods, etc. are also changed accordingly.
    Old:
test.rb:1:in `foo': undefined method `time' for an instance of Integer
        from test.rb:2:in `<main>'

New:
test.rb:1:in 'Object#foo': undefined method 'time' for an instance of Integer
        from test.rb:2:in '<main>'

C API updates

  • rb_newobj and rb_newobj_of (and corresponding macros RB_NEWOBJ, RB_NEWOBJ_OF, NEWOBJ, NEWOBJ_OF) have been removed. [Feature #20265]
  • Removed deprecated function rb_gc_force_recycle. [Feature #18290]

Miscellaneous changes

  • Passing a block to a method which doesn’t use the passed block will show a warning on verbose mode (-w). [Feature #15554]

  • Redefining some core methods that are specially optimized by the interpeter and JIT like String.freeze or Integer#+ now emits a performance class warning (-W:performance or Warning[:performance] = true). [Feature #20429]

See GitHub releases like Logger or changelog for details of the default gems or bundled gems.

See NEWS or commit logs for more details.

With those changes, 4820 files changed, 196907 insertions(+), 253488 deletions(-) since Ruby 3.3.0!

Download

  • https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.0-rc1.tar.gz

    SIZE: 23055998
SHA1: 216e3085ab8b886b9f74943ee5b62bd2e3d86671
SHA256: 1f3187d3366e90af6d760994f8bfe1fe8999a8ba3553ea4dcfae63e548236e2a
SHA512: 0b0420a39c0bf3b38600d4e28805a581c4b5a6cf2abe41be8c8164276a8044a19e676de74eea5dd5b4d7d667d821a6144119795fea510fd4ba6e34865a2ae172

  • https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.0-rc1.tar.xz

    SIZE: 17116016
SHA1: 1424671cdc9c4bfe3778ac159d917c8bfe6107bd
SHA256: 9c54225747f7a786727aa6213503083d5d8ff7097505d4b7456ff60880ee4a17
SHA512: 5b92a2b5829ab23735617945839e45df984b319b8932e790a8e0c6f681b9bd74249511a76345516cc216c002ed7887bdd27151501491d5ecedc20acd3fb57cc5

  • https://cache.ruby-lang.org/pub/ruby/3.4/ruby-3.4.0-rc1.zip

    SIZE: 28323595
SHA1: 4ae8ce4b15ccc3f0c6f42e408c44aa287a1ccc14
SHA256: 653162a2db627e8e5feee22a00b20acf215509d88b06ffb281bc8788ed12c74c
SHA512: c6c6b9a0e61308e3f3303cd148613feabb2ee12d8e2fefc1f4aa1403237310f7c9be5e2031248ea89ff01cdc0bca1a66ff60f9f1f19ed9c9fccef3d7a3bbebb8

What is Ruby

Ruby was first developed by Matz (Yukihiro Matsumoto) in 1993, and is now developed as Open Source. It runs on multiple platforms and is used all over the world especially for web development.