On Sun, 6 Jun 2021, Tom Honermann via Gcc-patches wrote: > When -fchar8_t support is enabled for non-C++ modes, the _CHAR8_T_SOURCE macro > is predefined. This is the mechanism proposed to glibc to opt-in to > declarations of the char8_t typedef and c8rtomb and mbrtoc8 functions proposed > in N2653. See [2].
I don't think glibc should have such a feature test macro, and I don't think GCC should define such feature test macros either - _*_SOURCE macros are generally for the *user* to define to decide what namespace they want visible, not for the compiler to define. Without proliferating new language dialects, __STDC_VERSION__ ought to be sufficient to communicate from the compiler to the library (including to GCC's own headers such as stdatomic.h). -- Joseph S. Myers jos...@codesourcery.com
