If you look at C++ standard support in major compilers, you'll find that no compiler on earth supports the whole C++20 standard. Gcc is the one that gets closes

If you look at C++ standard support in major compilers, you'll find that no compiler on earth supports the whole C++20 standard. Gcc is the one that gets closest, but still has several "partially supported" features. https://en.cppreference.com/w/cpp/20 https://en.cppreference.com/w/cpp/20