commit https://github.com/vim/vim/commit/46bbb0c4ba27395859dfeaa26938483946bb4ec2 Author: Bram Moolenaar <Bram@vim.org> Date: Sat Jun 11 21:04:39 2016 +0200 patch 7.4.1919 Problem: Register contents is not merged when writing viminfo. Solution: Use timestamps for register contents.

" 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