patch 8.1.0370: not using internal diff if 'diffopt' is not changed commit https://github.com/vim/vim/commit/274cea35c6d409cfb16862ff24e789b2d3ea3ee3 Author: Bram Moolenaar <Bram@vim.org> Date: Wed Sep 12 18:00:12 2018 +0200 patch 8.1.0370: not using internal diff if 'diffopt' is not changed Problem: Not using internal diff if 'diffopt' is not changed. Solution: Correct initialization of diff_flags. (Christian Brabandt)