These cases are not caught by clang: https://godbolt.org/z/E3dWds9o6 ```cpp #include <optional> #include <set> #include <string> #include <string_view> #include <vector> std::string GetString() { return "foo"; } void Test() { // Bad. std::set<std::string_view> s = {GetString(), GetString()}; std::vector<std::string_view> v = {GetString(), GetString()}; // Good. std::optional<std::string_view> t2 = GetString(); // warning here. } ``` cc: @hokein related bug which was closed: https://github.com/llvm/llvm-project/issues/100526