It sure freaking does. I just upgraded our toolchains on KallistiOS to use the absolute latest GCC12.2.0 with latest Newlib and Binutils and brought C++20 to the damn thing! I'm using freaking C++ concepts and constraints with meta templates and Objective-C++ craziness on a DC.
https://github.com/KallistiOS/KallistiOS/commit/99c716c8915f...