There Are No Zero-Cost Abstractions in C++

HN commenters cite it whenever zero-cost abstraction claims come up, especially for why unique_ptr is not free on some ABIs.

Chandler Carruth argues in a CppCon 2019 talk that C++ has no truly zero-cost abstractions. Using examples like unique_ptr, ABI constraints and compile-time costs, he shows that abstractions cost runtime, compile time or human effort.