Relax void * casting in C++

I'd suggest either simply using C style casts, or wrapping the cast in a macro that either expands to nothing (in C), or a static_cast in C++.

If your compiler supports decltype(), you can use some macro magic to avoid having to explicitly repeat the type name (and, thanks to sizeof, the element size):

#ifdef __cplusplus
#define my_calloc(VAR, COUNT) \
    static_cast<decltype(VAR)>(std::calloc(COUNT, sizeof *VAR))
#else
#define my_calloc(VAR, COUNT) calloc(COUNT, sizeof *VAR)
#endif

Example usage:

#ifdef __cplusplus
#include <cstdlib>
#else
#include <stdlib.h>
#endif

struct Cpfs *cpfs = my_calloc(cpfs, 42);

The cleaner solution would probably be to just use a C compiler and link the object files, though...