C, still?

C, still?

"But then one needs to win holy war against allocators returning "void *""

If you mean the problem is just that you need to add explicit casts in a million places, maybe you could avoid that relatively cleanly with:

class autocast {
public:
  autocast(void *p) : ptr(p) { }
  template<typename T> operator T*() {
    return static_cast<T*>(ptr);
  }
private:
  void *ptr;
};

#define kmalloc(size, flags) autocast(kmalloc(size, flags))

so it can be implicitly cast to any pointer type (with zero runtime cost).

(Hmm, I wonder if you could then extend it to something like:

template<size_t size>
class checked_autocast {
public:
  checked_autocast(void *p) : ptr(p) { }
  template<typename T> operator T*() {
    static_assert(size >= sizeof(T), "allocated size smaller than return type");
    return static_cast<T*>(ptr);
  }
private:
  void *ptr;
};

#define kmalloc(size, flags) \
  __builtin_choose_expr( \
    __builtin_constant_p(size), \
    checked_autocast<size>(kmalloc(size, flags)), \
    autocast(kmalloc(size, flags)))

to detect some bugs.)