Replace matchstrpos() with match() + split() for backwards compatibility matchstrpos() was added to Vim as patch 7.4.1685: http://ftp.vim.org/vim/patches/7.4/7.4.1685 Older but still vendor-supported operating systems (such as Ubuntu 14.04 LTS and derivatives) ship versions of Vim that predate this patch. Replacing matchstrpos() allows vim-gutentags to continue to work with these older versions of Vim. Issue: https://github.com/ludovicchabant/vim-gutentags/issues/114