constexpr stacktrace_entry() noexcept;
constexpr native_handle_type native_handle() const noexcept;
constexpr explicit operator bool() const noexcept;
string description() const;
string source_file() const;
uint_least32_t source_line() const;
friend constexpr bool operator==(const stacktrace_entry& x, const stacktrace_entry& y) noexcept;