commit https://github.com/vim/vim/commit/f2c4c391192cab6e923b1a418d4af09106fba25f Author: Bram Moolenaar <Bram@vim.org> Date: Fri Jul 29 20:50:24 2016 +0200 patch 7.4.2117 Problem: Deleting an augroup that still has autocmds does not give a warning. The next defined augroup takes its place. Solution: Give a warning and prevent the index being used for another group name.