Repository navigation
[browser][wasm] Handle null task exception message #38803
Description
Executing the following:
Task testTask = null;
await testTask;
Will print the following.
dotnet.js:8653 Uncaught (in promise) System.AggregateException: One or more errors occurred. (Object reference not set to an instance of an object.)
---> System.NullReferenceException: Object reference not set to an instance of an object.
at Test.Client.Main(JSObject output)
--- End of inner exception stack trace ---
Other times it prints something like the following with a tp callback threw a System.NullReferenceException
dotnet.js:2356
dotnet.js:2356 Unhandled Exception:
dotnet.js:2356 System.NullReferenceException: Object reference not set to an instance of an object.
dotnet.js:2356 at Test.Client.CloseWebSocket(String closeReason)
dotnet.js:2356 at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__140_1(Object state)
dotnet.js:2356 at System.Threading.QueueUserWorkItemCallbackDefaultContext.Execute()
dotnet.js:2356 at System.Threading.ThreadPoolWorkQueue.Dispatch()
dotnet.js:2356 at System.Threading.ThreadPool.Callback()
dotnet.js:2344 tp callback threw a System.NullReferenceException
Code lines:
https://github.com/dotnet/runtime/blob/master/src/mono/mono/mini/mini-wasm.c#L606-L615
if (!is_ok (error)) {
printf ("tp callback failed due to %s\n", mono_error_get_message (error));
mono_error_cleanup (error);
}
if (exc) {
char *type_name = mono_type_get_full_name (mono_object_class (exc));
printf ("tp callback threw a %s\n", type_name);
g_free (type_name);
}
Activity
[-][browser][wasm] Handle null task exception [/-][+][browser][wasm] Handle null task exception message[/+]kg commentedon Jul 27, 2020
I've been trying to reproduce this and can't. There must be more to it, like a set of conditions that lead to it happening. Does it need to be running in a browser environment in particular, or in node? Does the await need to happen in an event handler or a threadpool task?
kjpou1 commentedon Jul 28, 2020
The issue may be a little misleading. The issue is basically documenting that the
messagebeing displayed is a little weird and probably should be changed fromtptothread pool.The system handles the case correctly though.
Update threadpool callback error messages to fix dotnet#38803
Update threadpool callback error messages to fix dotnet/runtime#38803
Update threadpool callback error messages to fix dotnet/runtime#38803 (…
Update threadpool callback error messages to fix dotnet#38803 (dotnet…