In my university they always told me to cast the return of void * functions, I thought it was just to avoid the warning saying "automatic cast of void* to int*" or similar.
It is supposed to provide you more checking by disabling automatic cast from void* to any other pointer. This makes sense in C++ since casting a pointer to a class can trigger some address adjustement if the target class of this instance pointed to is multiple derived (and maybe in other cases?). There is no way such adjustment can happen if the source type is void*, because then you don't know what the source type really is.
