From e64a342a9fd2ee16e17f3534662afd9dd21c2819 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 9 Jan 2019 20:09:18 +0100
Subject: [PATCH] task: fix error awaiting already scheduled task

To reproduce this issue, try `await taskMgr.add(Task.pause(1.0))`
---
 panda/src/event/pythonTask.cxx | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/panda/src/event/pythonTask.cxx b/panda/src/event/pythonTask.cxx
index 554e1368e7..86200802a9 100644
--- a/panda/src/event/pythonTask.cxx
+++ b/panda/src/event/pythonTask.cxx
@@ -598,7 +598,9 @@ do_python_task() {
             // directly instead of having to do:
             //   await taskMgr.add(Task.pause(1.0))
             AsyncTask *task = (AsyncTask *)fut;
-            _manager->add(task);
+            if (!task->is_alive()) {
+              _manager->add(task);
+            }
           }
           if (fut->add_waiting_task(this)) {
             if (task_cat.is_debug()) {