+/// @brief Make \a path an absolute path.
+///
+/// Makes \a path absolute using the \a current_directory if it is not already.
+/// An empty \a path will result in the \a current_directory.
+///
+/// /absolute/path => /absolute/path
+/// relative/../path => <current-directory>/relative/../path
+///
+/// @param path A path that is modified to be an absolute path.
+/// @returns errc::success if \a path has been made absolute, otherwise a
+/// platform-specific error_code.
+std::error_code make_absolute(const Twine ¤t_directory,
+ SmallVectorImpl<char> &path);
+