Zhenchi

``` $ uname -a Darwin zhongzc-mac 20.6.0 Darwin Kernel Version 20.6.0: Wed Jun 23 00:26:31 PDT 2021; root:xnu-7195.141.2~5/RELEASE_X86_64 x86_64 ```

> I can have a look tonight. > > Can you share details on the OS version you are running it on? keep waiting for your reply

才搜到这个ISSUE，今天才解决了问题... 值得置顶 orz

> @zhongzc 我不是早就在依赖里面加了这个吗？ 我也不是很清楚，这边是企业微信，大概两个月前的事情。

Can you provide a minimal reproducible example?

For this example, I'm afraid it's a misuse of minitrace. The `root` span should be dropped before `collect`, or the collection will be never performed. You can try: ```rust let...

> my apologies, it fails with `drop(root)` and > > ```rust > fn().in_span(root).await; > ``` > > too. > > Note that for these cases, it works when I swap...

Not a bug. To make things easier, we decided to let async functions with `#[trace("a-span")]` construct thread-safe `Span` while sync functions with `#[trace("a-span")]` construct `LocalSpan`. Only if users provide arg...

> > printing a warning to std out when there are no traces other than "root" > > This seems like the only solution... But I'm not sure whether someone...

I agree that we provide the same `max_level_*` and `release_max_level_*` like log. Ref: https://docs.rs/log/latest/log/#compile-time-filters