Issue #19413 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #19413: Can't move object when 2 ivars refer to same object https://bugs.ruby-lang.org/issues/19413 * Author: luke-gru (Luke Gruber) * Status: Open * Priority: Normal * Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN ---------------------------------------- ```ruby class A def initialize @a = Object.new @b = @a end end r = Ractor.new do |err| obj = receive p obj end r.send(A.new, move: true) # Allocator undefined for Ractor::MovedObject r.take ``` To fix it we could have a hash of old to new objects during traversal/replacement and use the same new object over again if necessary. -- https://bugs.ruby-lang.org/