2020/03/06/ On static variables, static storage, static initialization, constant initialization, constinit, constexpr · GitBook
![c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow](https://i.stack.imgur.com/ByQQ7.png)
c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow
map_field.h:332:37: error: constexpr constructor never produces a constant expression [-Winvalid-constexpr] · Issue #8150 · protocolbuffers/protobuf · GitHub
![c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow](https://i.stack.imgur.com/cX6Em.png)
c++ - literal class compile error with constexpr constructor and function (differ vc, g++) - Stack Overflow
![constexpr ctor does not work on Windows with nvcc. · Issue #8128 · protocolbuffers/protobuf · GitHub constexpr ctor does not work on Windows with nvcc. · Issue #8128 · protocolbuffers/protobuf · GitHub](https://user-images.githubusercontent.com/5203025/101525471-58241680-39c6-11eb-82a6-7d2ed5e2f2cb.png)