C++ Integer to String

Hi /prog/.

I am right now working on my C++ project for my programming class and I started wondering. What method's do you use to convert integer to string? There is so many of them, and most require at least 4 additional code lines. Which method do you prefer?

#define INTEGERTOSTRING(i)\
 ({\
   __typeof__(i) _i = (i), negative = _i < 0 ? 1 : 0;\
   const char digits = "0123456789";\
   char *str = malloc((size_t)log10(_i) + 2 + negative) + (int)log10(_i) + 2 + negative;\
   *str-- = 0;\
   for(; _i; _i /= 10) *str-- = digits[_i % 10];\
   if(negative) *str-- = '-';\
   ++str;\
  })