=== RUN   TestRace
test output
2 0xc4200153d0
==================
WARNING: DATA RACE
Write at 0x00c4200153d0 by goroutine 7:
  race_test.TestRace.func1()
      race_test.go:13 +0x3b

Previous write at 0x00c4200153d0 by goroutine 6:
  race_test.TestRace()
      race_test.go:15 +0x136
  testing.tRunner()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:657 +0x107

Goroutine 7 (running) created at:
  race_test.TestRace()
      race_test.go:14 +0x125
  testing.tRunner()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:657 +0x107

Goroutine 6 (running) created at:
  testing.(*T).Run()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:697 +0x543
  testing.runTests.func1()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:882 +0xaa
  testing.tRunner()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:657 +0x107
  testing.runTests()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:888 +0x4e0
  testing.(*M).Run()
      /usr/local/Cellar/go/1.8.3/libexec/src/testing/testing.go:822 +0x1c3
  main.main()
      _test/_testmain.go:52 +0x20f
==================
--- FAIL: TestRace (0.00s)
	testing.go:610: race detected during execution of test
FAIL
exit status 1
FAIL	race_test	0.015s