Go to the source file and line corresponding to this hunk (@code{diff-goto-source}). By default, this jumps to the ``new'' version of the file, the one shown first on the file header. With a prefix argument, jump to the ``old'' version instead. If @code{diff-jump-to-old-file} is non-@code{nil}, this command by default jumps to the ``old'' file, and the meaning of the prefix argument is reversed. If the prefix argument is a number greater than 8 (e.g., if you type @kbd{C-u C-u C-c C-c}), then this command also sets @code{diff-jump-to-old-file} for the next invocation. If the source file is under version control (@pxref{Version Control}), this jumps to the work file by default. With a prefix argument, jump to the ``old'' revision of the file (@pxref{Old Revisions}), when point is on the old line, or otherwise jump to the ``new'' revision.