commit https://github.com/vim/vim/commit/5ca84ce4aa2832041f843e624c222bbc1f4d3e14 Author: Bram Moolenaar <Bram@vim.org> Date: Wed Mar 23 22:28:25 2016 +0100 patch 7.4.1641 Problem: Using unterminated string. Solution: Add NUL before calling vim_strsave_shellescape(). (James McCoy)

" Settings for test script execution
" Always use "COMMAND.COM", don't use the value of "$SHELL".
set shell=c:\COMMAND.COM shellquote= shellxquote= shellcmdflag=/c shellredir=>
" This is used only when the +eval feature is available.
if executable("cmd.exe")
   set shell=cmd.exe
endif