Ruby Issue Tracking System

06/29/2026

06:21 AM Ruby Feature #22130: Add a new YARV instruction for a `String.new` fast path

How about to introduce `String.new_buffer(capacity)` or some other name if it is important for the performance? ko1 (Koichi Sasada)

02:03 AM Ruby Feature #22132: Scala-like for comprehensions

also this proposal contains extension like `for iter1, iter2 do ... end`? ko1 (Koichi Sasada)

02:00 AM Ruby Feature #22132: Scala-like for comprehensions

just curious: `for ... then` for single iterator will makes `map` behavior like that?
```ruby
for a in ary do
a
end
# ary.each{it}
for a in ary then
a
end
# ary.map{it}
```
ko1 (Koichi Sasada)

06/26/2026

04:43 AM Ruby Feature #22130: Add a new YARV instruction for a `String.new` fast path

Does it affect app performance? ko1 (Koichi Sasada)

06/23/2026

03:07 AM Ruby Feature #22121: Introduce Parallel Sweep feature

> I would like to have an additional "sweep thread" that sweeps alongside the Ruby GC thread (in parallel) and at the same time as Ruby code is running (concurrent). When the sweep thread is working alongside the Ruby GC thread, both thr... ko1 (Koichi Sasada)

06/18/2026

12:04 AM Ruby Feature #22067: New RUBY_TYPED_THREAD_SAFE_FREE bit to declare thread safe dfree functions

This was approved by Matz. ko1 (Koichi Sasada)

06/15/2026

11:53 PM Ruby Revision f1154323 (git): Keep curry's argument array alive across the inner call

In the call branch of `curry`, `passed` is the only reference keeping the
freshly built argument array alive, yet its backing buffer is handed to
`rb_proc_call_with_block` as `argv` via `RARRAY_CONST_PTR(passed)`. After
taking that point... ko1 (Koichi Sasada)

06/14/2026

07:13 PM Ruby Revision 7c36a0cf (git): Run GC event hooks on the current EC

rb_gc_event_hook() ran hooks on rb_gc_get_ec(), which during GC returns
the GC's snapshot (objspace->vm_context.ec, captured at marking). When a
lazy sweep is continued from another thread's allocation, that snapshot
belongs to the marki... ko1 (Koichi Sasada)

05:21 PM Ruby Revision 39c0b0b6 (git): add error message on non-iseq

ko1 (Koichi Sasada)

11:59 AM Ruby Revision 5e700b36 (git): vm_dump.c: note when there is no Ruby execution context

rb_vm_bugreport() silently skipped the control frame information, Ruby
level backtrace, and threading sections when vm or ec was NULL, so the
report jumped straight to the machine register context with no explanation
of why no Ruby level... ko1 (Koichi Sasada)