C++ smart pointers

Question

So smart pointers are nothing but classes that wrap a raw pointer, only the object contains a destructor that calls delete

if that's exact is there any reason to use traditional raw pointers? is it always more convenient to use smart pointers?

Answer 1

Smart pointers come with a certain overhead. If you don't need the functionality a smart pointer offers (automatic memory management through RAII) then just stick to using raw pointers. Remember, raw pointers themselves are not necessarily bad, raw pointers that own resources are. Ownership requires explicit delete-ion. We don't want that.

Answer 2

Smart pointers are one form of resource management. There are others which may be more appropriate. For example, for a memory-only graph of objects (i.e., none of the objects hold a non-memory resource of any form) using allocations into an arena and letting go of the arena is more effective: it has much smaller overhead and is substantially faster to release, especially if the objects are not necessarily hot in cache. The object graphs maintained within the arena is linked using raw pointers.

Smart pointers are one of many tools for resource management. They tend to be overused by people unaware of other tools. Of course, that is a common pattern: to thee who only wield a hammer everythings looks like a nail!