This gets to the heart of effective type rules, which are complex, confusing, and not properly implemented by compilers. C and C++ definitely diverge here, because C is less ambitious in its object model (which mean it just simply leaves so many details about it undiscussed).

Malloc returns memory that is uninitialized and has no type. The effective type of that memory is initialized on first use by C, whereas C++ relies on angelic nondeterminism to magically initialize the type at return type to whatever will work in the future.