Issue #21368 has been updated by osyoyu (Daisuke Aritomo). File 0001-Bug-21368-Transfer-finalizer-when-moving-between-Rac.patch added The script in the description didn't crash in my environments (the following). Explicitly calling `GC.start` did. - Linux `ruby 3.5.0dev (2025-05-28T04:34:40Z master d064fd067b) +PRISM [x86_64-linux]` - macOS `ruby 3.5.0dev (2025-05-28T04:34:40Z master d064fd067b) +PRISM [arm64-darwin24]` ```ruby r = Ractor.new do Ractor.receive # don't bind to a variable (let it be garbage collected) GC.start end o = Object.new ObjectSpace.define_finalizer(o, proc { |id| }) r.send(o, move: true) r.take ``` I have attached an updated version of @zzak_'s patch which resolves this crash, but I suppose this is inappropiate since this will leak outer variables in the following case: ```ruby r = Ractor.new do Ractor.receive GC.start # `unshareable` happens to get read in this Ractor end o = Object.new unshareable = +"hello" ObjectSpace.define_finalizer(o, proc { |id| p unshareable }) r.send(o, move: true) r.take ``` Maybe simply marking objects with a finalizer ineligible for moving is more appropiate. ---------------------------------------- Bug #21368: Moving objects with finalizer between Ractors crashes https://bugs.ruby-lang.org/issues/21368#change-113475 * Author: peterzhu2118 (Peter Zhu) * Status: Assigned * Assignee: ractor * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- When an object is moved to a different Ractor, the finalizers are not copied to the new object, so it will have the `FL_FINALIZE` flag set but no entry in the finalizer table. The following script crashes: ```ruby r = Ractor.new do loop { Ractor.receive } end 1_000.times do o = Object.new ObjectSpace.define_finalizer(o, proc { |id| }) r.send(o, move: true) end ``` ---Files-------------------------------- 0001-Bug-21368-Transfer-finalizer-when-moving-between-Rac.patch (883 Bytes) -- https://bugs.ruby-lang.org/