Bug #19372: Proc objects are not traversed for shareable check during Ractor.make_shareable(prok)

• Status: Assigned
• Assignee: ko1 (Koichi Sasada)
• Target version: -
• Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN

[luke-gru (Luke Gruber)]

class Proc
  attr_accessor :obj1
  def initialize
    @obj1 = Object.new
  end
end

p = true.instance_eval { Proc.new { puts "hi" } }
Ractor.make_shareable(p)
p "Obj1 frozen?", Ractor.shareable?(p.obj1)
P = p

r = Ractor.new do
  pp = P
  p pp.obj1 # gives error in debug builds (rb_ractor_confirm_belonging rb_bug() call)
end

[luke-gru (Luke Gruber)]

A separate but related issue is that the proc objects are not frozen too, so their ivars can be (re)assigned. I don't know how big an issue that is because
other ractors cannot read/write the ivars but IMO the proc should be frozen.

[nobu (Nobuyoshi Nakada)]

Maybe https://github.com/nobu/ruby/tree/ractor-unshareable-data fixes it?

[luke-gru (Luke Gruber)]

No I don't think so, that change would just make it so that obj.freeze has the effect of making obj shareable for that class. However, prok.freeze should never make
procs shareable, they need to go through the isolation check.

[luke-gru (Luke Gruber)]

PR here: https://github.com/ruby/ruby/pull/7182

[hsbt (Hiroshi SHIBATA)]

• Status changed from Open to Assigned
• Assignee set to ko1 (Koichi Sasada)