nr, nbytes, err := buf.ReadRune()
		if nr != r || nbytes != size || err != nil {
			t.Fatalf("ReadRune(%U) got %U,%d not %U,%d (err=%s)", r, nr, nbytes, r, size, err)
		}
	}

	// Check that UnreadRune works
	buf.Reset()

	// check at EOF
	if err := buf.UnreadRune(); err == nil {
		t.Fatal("UnreadRune at EOF: got no error")
	}
	if _, _, err := buf.ReadRune(); err == nil {

	export GOARCH=$(echo $target | sed 's/.*-//')
	unset GOARM
	if [ "$GOARCH" = "arm5" ]; then
		export GOARCH=arm
		export GOARM=5
	fi

	# Build and vet everything.
	# cmd/go/internal/work/exec.go enables the same vet flags during go test of std cmd
	# and should be kept in sync with any vet flag changes here.
	if ! "$GOROOT/bin/go" build std cmd || ! "$GOROOT/bin/go" vet -unsafeptr=false std cmd; then
		failed=true

correctly, unchanged, over the lifetime of that specification.
More generally, as adjustments are made and features added to the language,
the compatibility guarantee ensures that a Go program that works with a
specific Go language version will continue to work with any subsequent version.
</p>

<p>
For instance, the ability to use the prefix <code>0b</code> for binary
integer literals was introduced with Go 1.13, indicated