tmux always modify my zsh PATH
After googling, I've found this:

https://coderwall.com/p/4l16zq/pyenv-inside-tmux-with-zsh-on-a-mac
http://pgib.me/blog/2013/10/11/macosx-tmux-zsh-rbenv/

And the fix to me is that (/etc/zprofile):

# system-wide environment settings for zsh(1)
if [ -x /usr/libexec/path_helper ]; then
  if [ -z "$TMUX" ]; then
    eval `/usr/libexec/path_helper -s`
  fi
fi