diff --git a/spec/concurrent/executor/cached_thread_pool_spec.rb b/spec/concurrent/executor/cached_thread_pool_spec.rb
index 1e502473e..048d6e2ec 100644
--- a/spec/concurrent/executor/cached_thread_pool_spec.rb
+++ b/spec/concurrent/executor/cached_thread_pool_spec.rb
@@ -212,6 +212,8 @@ module Concurrent
               pid       = spawn RbConfig.ruby, test_file
               Process.waitpid pid
               expect($?.success?).to eq true
+            rescue Errno::ECHILD
+              # child already gone
             rescue Timeout::Error => e
               Process.kill :KILL, pid
               raise e