diff --git a/components/style/properties.mako.rs b/components/style/properties.mako.rs
index 52eefd96c3e..e9230819357 100644
--- a/components/style/properties.mako.rs
+++ b/components/style/properties.mako.rs
@@ -6641,8 +6641,8 @@ pub fn modify_style_for_text(style: &mut Arc<ComputedValues>) {
             style.padding.padding_right != computed::LengthOrPercentage::Length(Au(0)) ||
             style.padding.padding_bottom != computed::LengthOrPercentage::Length(Au(0)) ||
             style.padding.padding_left != computed::LengthOrPercentage::Length(Au(0)) {
-        let mut style = Arc::make_unique(style);
-        let mut padding = Arc::make_unique(&mut style.padding);
+        let mut style = Arc::make_mut(style);
+        let mut padding = Arc::make_mut(&mut style.padding);
         padding.padding_top = computed::LengthOrPercentage::Length(Au(0));
         padding.padding_right = computed::LengthOrPercentage::Length(Au(0));
         padding.padding_bottom = computed::LengthOrPercentage::Length(Au(0));
diff --git a/components/style/values.rs b/components/style/values.rs
index 9542ae563bd..659c66dc9e0 100644
--- a/components/style/values.rs
+++ b/components/style/values.rs
@@ -639,6 +639,7 @@ pub mod specified {
     }
 
     impl ToCss for Calc {
+        #[allow(unused_assignments)]
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
 
             macro_rules! count {