Error with concurrent task

Mojo
1

I got an error with concurrent task. Can anyone help?

from runtime.asyncrt import TaskGroup

@parameter
@always_inline
async fn task1():
    while True:
        pass

fn main() raises:
    var tg = TaskGroup()
    tg.create_task(task1())    
    while True:
        pass

$ mojo life.mojo
LLVM ERROR: destroying a non-available AsyncValue isn't implemented
Aborted (core dumped)
2

You need to call .wait.

from runtime.asyncrt import TaskGroup


@parameter
@always_inline
async fn task1():
    while True:
        pass


fn main() raises:
    var tg = TaskGroup()
    tg.create_task(task1())
    tg.wait()

The compiler is destroying the tg after its last use, which is before that loop, which is what the error message is about.

3

How to let the concurrent task runs forever without waiting for its completion?

4

Regardless of the helpful fix suggested by @duck_tape, I think the compiler should fail more gracefully. Could you please file a bug on GitHub?

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