atomic_wait and similar methods in c++ 20 and g++ 10.2

Question

I am compiling with g++ 10.2 using -std=c++20 but i get errors like error: ‘atomic_notify_one’ is not a member of ‘std’. I see in the docs that those methods are supported in c++20. Do i miss something?

Answer 1

As far as I understand neither g++-10.2 nor g++-10.3 does not support atomic_notify_one. However, here the trunk version of the compiler (in which __cplusplus is equal to 202002), as well as my local unstable version of the compiler g++-11.0 (in which __cplusplus is also equal to 202002) perfectly cope with the functions atomic_notify_one, atomic::notify_one

And BTW, unfortunately I did not find official support information. In some places it is introduced in g++-10, in some it is still not implemented yet. Cppreference says it is implemented in g++-11, so I guess it is. In general I would not rush to use atomic_notify_one in production