cygwin下安装vim插件管理器vundle总是提示E117: Unknown function: vundle#end

配置文件是github上的。
rtp确认了N遍没问题

set nocompatible " be iMproved, required
filetype off " required

" set the runtime path to include Vundle and initialize
set rtp+=~/.vim/bundle/Vundle.vim
call vundle#begin()
" " alternatively, pass a path where Vundle should install plugins
" "call vundle#begin('~/some/path/here')
"
" " let Vundle manage Vundle, required
Plugin 'VundleVim/Vundle.vim'
"
" " The following are examples of different formats supported.
" " Keep Plugin commands between vundle#begin/end.
" " plugin on GitHub repo
" Plugin 'tpope/vim-fugitive'
" " plugin from http://vim-scripts.org/vim/sc...
" Plugin 'L9'
" " Git plugin not hosted on GitHub
" Plugin 'git://git.wincent.com/command-t.git'
" " git repos on your local machine (i.e. when working on your own plugin)
" Plugin 'file:///home/gmarik/path/to/plugin'
" " The sparkup vim script is in a subdirectory of this repo called vim.
" " Pass the path to set the runtimepath properly.
" Plugin 'rstacruz/sparkup', {'rtp': 'vim/'}
" " Install L9 and avoid a Naming conflict if you've already installed a
" " different version somewhere else.
" Plugin 'ascenator/L9', {'name': 'newL9'}
"
" " All of your Plugins must be added before the following line
call vundle#end() " required
filetype plugin indent on " required