1 files changed, 1 insertions, 0 deletions
diff --git a/thread.c b/thread.c
index c51499488f..78571590cf 100644
--- a/thread.c
+++ b/thread.c
@@ -3955,6 +3955,7 @@ rb_check_deadlock(rb_vm_t *vm)
 	printf("%d %d %p %p\n", vm->living_threads->num_entries, vm->sleeper, GET_THREAD(), vm->main_thread);
 	st_foreach(vm->living_threads, debug_i, (st_data_t)0);
 #endif
+	vm->sleeper--;
 	rb_thread_raise(2, argv, vm->main_thread);
     }
 }