GCC does not support _Generic in C++ mode. Use inline function definitions with function overloading in __cplusplus mode.
- stdbit.stdc_leading_zeros_uc - stdbit.stdc_leading_zeros_us - stdbit.stdc_leading_zeros_ui - stdbit.stdc_leading_zeros_ul - stdbit.stdc_leading_zeros_ull Test via: $ ninja libc-stdbit-tests libc_include_tests