Why do I need to keep track of the lifetime of the scope/span objects myself?

I'm trying to instrument some code that's used in a library that has very specific code flow. Keeping track of the spans and scopes myself is very tricky because I can't pass the spans/scopes. I have to store them in some locally managed storage.

In other tracing libraries (not c++), I've always just been able to do the equivalent of tracer->StartSpan(), and then some time later tracer->CurrentSpan()->End() or whatever. Is there advice on managing scopes if their lifetime is complicated? The only ways I see it working are global state, or polluting the types of all my functions to pass the scope around.

The issue names tracer->StartSpan(), tracer->CurrentSpan(), and End() as the relevant entry points, but identifies no file or test. Start by examining the C++ tracing API's scope and span lifetime behavior around these calls; done would require an agreed approach or documented guidance for managing scopes with complex lifetimes.