patch 8.0.0561: undefined behavior when using backslash after empty line commit https://github.com/vim/vim/commit/478af67dd6a9adc456464c3736bda328ae3a28cb Author: Bram Moolenaar <Bram@vim.org> Date: Mon Apr 10 22:22:42 2017 +0200 patch 8.0.0561: undefined behavior when using backslash after empty line Problem: Undefined behavior when using backslash after empty line. Solution: Check for an empty line. (Dominique Pelle, closes https://github.com/vim/vim/issues/1631)