@mloskot I wanted to discuss this PR with you before working on it again, but I thought currently the Boost 1.80 PRs are more important.

I think those structs belong to the detail namespace, but they are currently not. However, just moving stuff around would violate boosts deprecation policy, right?

So, some of my solutions:

• Keep the PR as is and have a possible breaking change if someone relied on those structs (I doubt it, but I am not sure).
• Create new detail structs, redirect the library calls to the detail structs and deprecate the old structs in the gil namespace.
• Leave everything as it is currently implemented and don't wake up sleeping dogs.