C++ Portable Varargs for "Variadic Macros" - Portable to GCC and MS Visual Studio

variadic.cpp

/*
 * Vairiadic Macros used in this form are portable to MSVC and GCC
 * https://gcc.gnu.org/onlinedocs/gcc/Variadic-Macros.html#Varia
 * https://msdn.microsoft.com/en-us/library/ms177415(v=vs.100).aspx
 */
 
#include <stdio.h>
#if __GNUC__
#define __FUNCSIG__ __PRETTY_FUNCTION__
#endif


void func( const char*fmt )
{
  printf("%s: " , __FUNCSIG__ );
   printf(fmt);
}

template<typename T1> 
void func( const char*fmt , const T1& d1)
{
    printf("%s: " , __FUNCSIG__ );
   printf(fmt,d1);
}

template<typename T1,typename T2> 
 void func( const char*fmt , const T1& d1 , const T2& d2 )
{
    printf("%s: " , __FUNCSIG__ );
   printf(fmt,d1,d2);
}

template<typename T1,typename T2,typename T3> 
void func( const char*fmt , const T1& d1 , const T2& d2, const T3& d3 )
{
    printf("%s: " , __FUNCSIG__ );
   printf(fmt,d1,d2,d3);
}
#define M1(...)  func( __VA_ARGS__)
#define M2(M,...)  func(M,## __VA_ARGS__)
#define M3(M,...)  func(M,__VA_ARGS__)




int main(int ac,char**av)
{
   M1("M1 hello\n");
   M1("M1 one %d\n",1);
   M1("M1 two %lf %s\n",(double).04,"string");
   M1("M1 three %s %llX %3.8lf\n" , "hi" , 0xFF00FF00FF00FF00LL , (double) 1. / 3. );
   M2("M2 hello\n");
   M2("M2 one %1.9lf\n",(double)1.03);
   M1("M2 two %lf %s\n",(double).04,"string");
   M2("M2 three %hd %s %f\n",(short)25,"foo",1.2);
   M3("M3 hello\n","");
   M3("M3 one %d\n",1);
   M3("M3 two %lf %s\n",(double).04,"string");
   M2("M3 three %hd %s %f\n",(short)25,"foo",1.2);

}
                                     

Updated to show use of templates with explicit args indirecting to function with varargs to demonstrate that macro varargs do not need to directly call functions expecting varargs.