check_bindiron commit refs: ref entry with NULL sha1 is can be a dangling symref (e01de1c)
   1#!/bin/sh
   2bindir="$1"
   3gitexecdir="$2"
   4gitcmd="$3"
   5if test "$bindir" != "$gitexecdir" -a -x "$gitcmd"
   6then
   7        echo
   8        echo "!! You have installed git-* commands to new gitexecdir."
   9        echo "!! Old version git-* commands still remain in bindir."
  10        echo "!! Mixing two versions of Git will lead to problems."
  11        echo "!! Please remove old version commands in bindir now."
  12        echo
  13fi