Lalit Kumar Bhasin

Reopening, as we still have warnings.

@ThomsonTan Yes, we should be enabling this for all platforms once warnings are cleaned-up.

This is weird. It works fine with `ubuntu 18.04 + gcc-4.8` and `ubuntu 20.04 + gcc-9.3` in our github CI environment. I did a quick test on ubuntu 18.04 and...

Thanks, @cqhan777, @Pupilsch, this is helpful.

@cqhan777 @Pupilsch - Is this issue still relevant, and reproducible?

@Briac-nt If it is the same problem, the patch from @cqhan777 should work for you: https://github.com/open-telemetry/opentelemetry-cpp/issues/1014#issuecomment-944821770 Please confirm.

> Is this issue still relevant after merging #504 ? Seems so - #211 was supposed to provide fix ( Dockerfile with having C++20 compiler ).

Moving to GA milestone, as this is related to documentation.

> Consider changing "bridge" to "shim" in the title (since the terminology has changed since this issue was created). Thanks, done.

Had a quick look into span api code, the problem I see here is that `api::Span` is an abstract class, which means we can't return a copy of it, so...