# Extra Clang Tools 22.1.2 documentation

## clang-tidy - cppcoreguidelines-avoid-reference-coroutine-parameters

# cppcoreguidelines-avoid-reference-coroutine-parameters

Warns when a coroutine accepts reference parameters. After a coroutine suspend point, references could be dangling and no longer valid. Instead, pass parameters as values.

Examples:

    std::future<int> someCoroutine(int& val) {
      co_await ...;
      // When the coroutine is resumed, 'val' might no longer be valid.
      if (val) ...
    }

This check implements CP.53 from the C++ Core Guidelines.