Bug #19411: GC issue with moved objects

• Status: Open
• Priority: Normal
• Assignee: -
• Target version: -
• ruby -v: 3.2.0
• Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN

[luke-gru (Luke Gruber)]

This crashes:

class Obj
  def initialize
    @obj = 3
  end
end

GC.stress = true
r = Ractor.new do
  obj = receive
  p obj
end
obj = Obj.new
r.send(obj, move: true)
r.take

It only crashes with nested objects, if you remove the ivar set in initialize it works fine. Maybe missing RB_GC_GUARD?

[luke-gru (Luke Gruber)]

The issue is again with shapes (related to https://bugs.ruby-lang.org/issues/19409). Newly moved objects (class MovedObject) need to have their shape reset to root shape. I'll make a PR for this.