Added [[noreturn]] to function SysError_

src/mpmo.h

@@ -147,7 +147,7 @@ Warning_(const char *caller, const std::string &format, Args const &... args) no
 }
 
 template <typename... Args>
-void
+[[noreturn]] void
 SysError_(const char *func, const std::string &format, Args const &... args) noexcept
 {
   int saved_errno = errno;