As of go 1.2

setupGOROOT.sh

#
# Place this code to your .profile, .bashrc, .bash_profile or whatever
#

program_exists () {
	type "$1" &> /dev/null ;
}


if program_exists go; then
	function setupGOROOT()
	{
		local GOPATH=`which go`
		local GODIR=`dirname $GOPATH`
		local GOPATH_BREW_RELATIVE=`readlink $GOPATH`
		local GOPATH_BREW=`dirname $GOPATH_BREW_RELATIVE`
		export GOROOT=`cd $GODIR; cd $GOPATH_BREW/../libexec; pwd`
	}
	setupGOROOT
fi