I'm trying to update all my projects to C++20. The C++ only projects work fine. All the Objective-C++ files, though, suddenly stop compiling. Is this supposed to work. I can't imagine [NSString stringWithUTF8String:foo] should be failing. Setting the project back to C++17 works.
I do have -fmodules and -fcxx-modules for clang modules in some projects. Do those all need to be removed for C++20 modules?