# From https://bugs.ruby-lang.org/issues/13526#note-1 Thread.report_on_exception = true sleep if $load $load = true n = 10 threads = Array.new(n) do Thread.new do begin autoload :Foo, File.expand_path(__FILE__) Thread.pass Foo ensure Thread.pass end end end Thread.pass until threads.all?(&:stop?) 1000.times { Thread.pass }