C++ Value Categories in Action: The Foundation Behind Overloads, Moves, and the Broader System

Lvalues, rvalues, xvalues, glvalues, prvalues, reference binding, std::move, and temporary materialization - we have heard of them, we use them regularly, and they are part of every C++ programmer’s daily work. But if I’m honest, my own grasp of how they truly interact had gotten a bit rusty until I revisited them with fresh eyes.

Why does std::move sometimes end up calling the copy constructor?

When exactly does the compiler materialize temporaries, and how does that affect which overload or constructor is chosen?

This talk shares the journey of going past surface-level rules to uncover the real mechanics: how these categories and expressions interact with overload resolution, when copy elision saves you, and how subtle traps can lead to unnecessary copies, dangling references, or surprising overload picks.

While this is primarily a basic to intermediate talk, I hope programmers at every level will leave with practical insights they can immediately apply to write cleaner, safer and faster C++ code.