patch 9.0.0101: invalid memory access in diff mode with "dp" and undo Commit: https://github.com/vim/vim/commit/4e677b9c40ccbc5f090971b31dc2fe07bf05541d Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jul 28 18:44:27 2022 +0100 patch 9.0.0101: invalid memory access in diff mode with "dp" and undo Problem: Invalid memory access in diff mode with "dp" and undo. Solution: Make sure the line number does not go below one.

this lines ends in a
this one doesn't
this one does
and the last one doesn't