You are 100% right. At some point I measured smart_ptr to be 25x slower than raw pointers. The compiler I am maintaining is not using C++ style smart pointers.

You are 100% right. At some point I measured smart_ptr to be 25x slower than raw pointers. The compiler I am maintaining is not using C++ style smart pointers. It is using a global whole program optimisation pass to reduce reference manipulation to a minimum. Basically what a world class C++ programmer with years of experience optimising performance would do. It is just done automatically.