@@ -229,7 +229,7 @@ func (b *Builder) build(stdout io.Writer, stderr io.Writer, out io.Writer) (stri

 	if len(b.options.Labels) > 0 {

 		line := "LABEL "

 		for k, v := range b.options.Labels {

-			line += fmt.Sprintf("%q=%q ", k, v)

+			line += fmt.Sprintf("%q='%s' ", k, v)

 		}

 		_, node, err := parser.ParseLine(line, &b.directive)

 		if err != nil {

@@ -6638,6 +6638,19 @@ func (s *DockerSuite) TestBuildLabelsOverride(c *check.C) {

 		c.Fatalf("Labels %s, expected %s", res, expected)

 	}

+	// Command line option labels with env var

+	name = "scratchz"

+	expected = `{"bar":"$PATH"}`

+	_, err = buildImage(name,

+		`FROM scratch`,

+		true, "--label", "bar=$PATH")

+	c.Assert(err, check.IsNil)

+

+	res = inspectFieldJSON(c, name, "Config.Labels")

+	if res != expected {

+		c.Fatalf("Labels %s, expected %s", res, expected)

+	}

+

 }

 // Test case for #22855