各编译器对c++20的支持情况

• Clang has partial C++20 support that can be enabled with the option -std=c++20 (version 10 and later) or -std=c++2a (version 9 and earlier).^[129]
• EDG eccp started implementing C++20 features in version 5.0 and as of version 6.1 supports most C++20 core language features.^[130]
• GCC added partial, experimental C++20 support in 2017^[131] in version 8 through the option -std=c++2a. Like Clang, GCC replaced this option with -std=c++20 in version 10. It also has an option to enable GNU extensions in addition to the experimental C++20 support, -std=gnu++20.^[132]
• Microsoft Visual Studio supports some C++20 features through its std:c++latest option. An option /std:c++20 to enable C++20 mode is expected as soon as the compiler is C++20 feature complete.^[133]