I want to delve into the implementation of function "printf" in C on macOS. "printf" uses the <stdarg.h> header file. I open the <stdarg.h> file and find that va_list is just a macro.
So, I am really curious about how the __builtin_va_list is implemented? I know it is compiler-specific. Where can I find the definition of the __builtin_va_list? Should I download the source code of clang compiler?