patch 8.0.0816: crash when using invalid buffer number commit https://github.com/vim/vim/commit/f144a3fb73340fe22e08bd1fa77e27c9f55bb0af Author: Bram Moolenaar <Bram@vim.org> Date: Sun Jul 30 18:02:12 2017 +0200 patch 8.0.0816: crash when using invalid buffer number Problem: Crash when using invalid buffer number. Solution: Check for NULL buffer. (Yasuhiro Matsumoto, closes https://github.com/vim/vim/issues/1899)