While "newlib" is an interesting idea - the approach taken here is, in many cases, the wrong one. You see, actually, the printf() family of functions don't act

While "newlib" is an interesting idea - the approach taken here is, in many cases, the wrong one. You see, actually, the printf() family of functions don't actually require _any_ metal, bare or otherwise, beyond the ability to print individual characters. For this reason, a popular approach for the case of not having a full-fledged standard library is to have a fully cross-platform implementation of the family which "exposes" a symbol dependency on a character printing function, e.g.: void putchar_(char c); and variants of the printf functions which take the character-printing function as a runtime parameter: int fctprintf(void (*out)(char c, void* extra_arg), void* extra_arg, const char* format, ...); int vfctprintf(void (*out)(char c, void* extra_arg), void* extra_arg, const char* format, va_list arg); this is the approach taken in the standalone printf implementation I maintain, originally by Marco Paland: https://github.com/eyalroz/printf https://github.com/eyalroz/printf