What version of Go are you using (go version)?

• 1.11

Does this issue reproduce with the latest release?

• yes (go1.11)

What did you do?

• Read code snippet in docs for https://golang.org/pkg/runtime/trace/#NewTask

What did you expect to see?

...
trace.WithRegion(ctx, "preparation", prepWork)
// preparation of the task
go func() {  // continue processing the task in a separate goroutine.
    defer task.End()
    trace.WithRegion(ctx, "remaining", remainingWork)
}()

What did you see instead?

...
trace.WithRegion(ctx, prepWork)
// preparation of the task
go func() {  // continue processing the task in a separate goroutine.
    defer task.End()
    trace.WithRegion(ctx, remainingWork)
}

The trace.WithRegion requires 3 parameters (ctx, regionType, fn) however in the code snippet for trace.NewTask, it seems to be missing some parameter.

It depends what prepWork and remainingWork represent here, but if they represent function (fn parameter) then this code snippet is misisng regionType parameter.

The code snippet is also missing () for the go func() ... call.