C style cast can be either a static_cast or reinterpret_cast, but it can also be a const_cast or a static+const or reinterpret+const. Finally, it will perform a static_cast that bypasses private inheritance (because the alternative would be to fall back to a reinterpret_cast, which is wrong if the static_cast needs to apply an offset to the pointer)

To add on top of sibling comment, C style casts are too lose, and the main reason for the new C++ style casts is improved type safety.

So instead of anything goes, there is some additional type checking depending on the type of cast being made.