// testing func in registerStdTest below. The tests are run
// sequentially, so there's no need for locks.
//
// ranGoBench and benchMatches are the same, but are only used
// in -race mode.
var (
	ranGoTest  bool
	stdMatches []string

	ranGoBench   bool
	benchMatches []string
)

func (t *tester) registerStdTest(pkg string) {