This is both awesome and very terrible at the same time. This proves that you can do magic in C but it also proves that C is really a low level assembler :-)

This is both awesome and very terrible at the same time. This proves that you can do magic in C but it also proves that C is really a low level assembler :-) For me, stuff like this has been one of the prime reasons to prefer C++ over C. You can totally get the same performance and compiled code when using templates. But you gain compile-time checking and much more robust code. (These preprocessor tricks are also popular in the BSD kernel)