A few notes on how I wrote 100% compile time checked printf-style format type checker. Source code is online on GitHub.
I recently worked again a bit on ezEngine, a beautiful Open Source game engine developed continuously by a few friends of mine in their spare time. ezEngine uses custom implemented formatting function that follows the style of (s)printf. Like printf it is C-varargs based and therefore not type safe. Example:
printf("%i", "not an int");