text: #!/usr/bin/env bash
  # Copyright 2013 The Go Authors. All rights reserved.
  # Use of this source code is governed by a BSD-style
  # license that can be found in the LICENSE file.
  
  # race.bash tests the standard library under the race detector.
  # http://golang.org/doc/articles/race_detector.html
  
  set -e
  
  function usage {
  	echo 'race detector is only supported on linux/amd64, freebsd/amd64 and darwin/amd64' 1>&2
  	exit 1
  }
  
  case $(uname) in
  "Darwin")
  	# why Apple? why?
  	if sysctl machdep.cpu.extfeatures | grep -qv EM64T; then
  		usage
  	fi 
  	;;
  "Linux")
  	if [ $(uname -m) != "x86_64" ]; then
  		usage
  	fi
  	;;
  "FreeBSD")
  	if [ $(uname -m) != "amd64" ]; then
  		usage
  	fi
  	;;
  *)
  	usage
  	;;
  esac
  
  if [ ! -f make.bash ]; then
  	echo 'race.bash must be run from $GOROOT/src' 1>&2
  	exit 1
  fi
  . ./make.bash --no-banner
  # golang.org/issue/5537 - we must build a race enabled cmd/cgo before trying to use it.
  go install -race cmd/cgo
  go install -race std
  
  # we must unset GOROOT_FINAL before tests, because runtime/debug requires
  # correct access to source code, so if we have GOROOT_FINAL in effect,
  # at least runtime/debug test will fail.
  unset GOROOT_FINAL
  
  go test -race -short std
  go test -race -run=nothingplease -bench=.* -benchtime=.1s -cpu=4 std
  