diff --git a/components/style/animation.rs b/components/style/animation.rs
index 941db59cc85..0a4c7cab345 100644
--- a/components/style/animation.rs
+++ b/components/style/animation.rs
@@ -19,8 +19,8 @@ use properties::longhands::animation_iteration_count::single_value::computed_val
 use properties::longhands::animation_play_state::computed_value::single_value::T as AnimationPlayState;
 use properties::longhands::transition_timing_function::single_value::computed_value::StartEnd;
 use properties::longhands::transition_timing_function::single_value::computed_value::T as TransitionTimingFunction;
-use std::sync::Arc;
 use std::sync::mpsc::Sender;
+use stylearc::Arc;
 use timer::Timer;
 use values::computed::Time;
 
diff --git a/components/style/attr.rs b/components/style/attr.rs
index 1989816329d..101810212b7 100644
--- a/components/style/attr.rs
+++ b/components/style/attr.rs
@@ -16,10 +16,10 @@ use servo_url::ServoUrl;
 use shared_lock::Locked;
 use std::ascii::AsciiExt;
 use std::str::FromStr;
-use std::sync::Arc;
 use str::{HTML_SPACE_CHARACTERS, read_exponent, read_fraction};
 use str::{read_numbers, split_commas, split_html_space_chars};
 use str::str_join;
+use stylearc::Arc;
 use values::specified::Length;
 
 // Duplicated from script::dom::values.
diff --git a/components/style/context.rs b/components/style/context.rs
index 581a7c12cd3..1cdd8c00636 100644
--- a/components/style/context.rs
+++ b/components/style/context.rs
@@ -27,8 +27,9 @@ use std::collections::HashMap;
 #[cfg(not(feature = "servo"))] use std::env;
 use std::fmt;
 use std::ops::Add;
-use std::sync::{Arc, Mutex};
+use std::sync::Mutex;
 use std::sync::mpsc::Sender;
+use stylearc::Arc;
 use stylist::Stylist;
 use thread_state;
 use time;
diff --git a/components/style/custom_properties.rs b/components/style/custom_properties.rs
index 95e43b46fdf..071efade790 100644
--- a/components/style/custom_properties.rs
+++ b/components/style/custom_properties.rs
@@ -14,8 +14,8 @@ use std::ascii::AsciiExt;
 use std::borrow::Cow;
 use std::collections::{HashMap, HashSet};
 use std::fmt;
-use std::sync::Arc;
 use style_traits::ToCss;
+use stylearc::Arc;
 
 /// A custom property name is just an `Atom`.
 ///
diff --git a/components/style/data.rs b/components/style/data.rs
index 4052f0b30a3..651f003e4e9 100644
--- a/components/style/data.rs
+++ b/components/style/data.rs
@@ -16,7 +16,7 @@ use selector_parser::{EAGER_PSEUDO_COUNT, PseudoElement, RestyleDamage, Snapshot
 use std::fmt;
 #[cfg(feature = "servo")] use std::hash::BuildHasherDefault;
 use std::ops::Deref;
-use std::sync::Arc;
+use stylearc::Arc;
 use stylist::Stylist;
 use thread_state;
 use traversal::TraversalFlags;
diff --git a/components/style/dom.rs b/components/style/dom.rs
index ffc46b0cc94..7a4fe5d1003 100644
--- a/components/style/dom.rs
+++ b/components/style/dom.rs
@@ -26,7 +26,7 @@ use std::fmt;
 use std::fmt::Debug;
 use std::hash::Hash;
 use std::ops::Deref;
-use std::sync::Arc;
+use stylearc::Arc;
 use stylist::ApplicableDeclarationBlock;
 use thread_state;
 
diff --git a/components/style/encoding_support.rs b/components/style/encoding_support.rs
index 2775de54893..92620378b30 100644
--- a/components/style/encoding_support.rs
+++ b/components/style/encoding_support.rs
@@ -13,7 +13,7 @@ use media_queries::MediaList;
 use self::encoding::{EncodingRef, DecoderTrap};
 use shared_lock::SharedRwLock;
 use std::str;
-use std::sync::Arc;
+use stylearc::Arc;
 use stylesheets::{Stylesheet, StylesheetLoader, Origin, UrlExtraData};
 
 struct RustEncoding;
diff --git a/components/style/gecko/data.rs b/components/style/gecko/data.rs
index 942aaf4f7b5..2e1e17a2ebc 100644
--- a/components/style/gecko/data.rs
+++ b/components/style/gecko/data.rs
@@ -15,8 +15,8 @@ use parking_lot::RwLock;
 use properties::ComputedValues;
 use shared_lock::{Locked, StylesheetGuards, SharedRwLockReadGuard};
 use std::collections::HashMap;
-use std::sync::Arc;
 use std::sync::mpsc::{Receiver, Sender, channel};
+use stylearc::Arc;
 use stylesheet_set::StylesheetSet;
 use stylesheets::{FontFaceRule, Origin, Stylesheet};
 use stylist::{ExtraStyleData, Stylist};
diff --git a/components/style/gecko/media_queries.rs b/components/style/gecko/media_queries.rs
index a0aeaec2e5c..2444338f174 100644
--- a/components/style/gecko/media_queries.rs
+++ b/components/style/gecko/media_queries.rs
@@ -18,11 +18,11 @@ use media_queries::MediaType;
 use parser::ParserContext;
 use properties::{ComputedValues, StyleBuilder};
 use std::fmt::{self, Write};
-use std::sync::Arc;
 use str::starts_with_ignore_ascii_case;
 use string_cache::Atom;
 use style_traits::ToCss;
 use style_traits::viewport::ViewportConstraints;
+use stylearc::Arc;
 use values::{CSSFloat, specified};
 use values::computed::{self, ToComputedValue};
 
diff --git a/components/style/gecko/restyle_damage.rs b/components/style/gecko/restyle_damage.rs
index 4d6c1269eb8..39fdafebd5d 100644
--- a/components/style/gecko/restyle_damage.rs
+++ b/components/style/gecko/restyle_damage.rs
@@ -10,7 +10,7 @@ use gecko_bindings::structs::{nsChangeHint, nsStyleContext};
 use gecko_bindings::sugar::ownership::FFIArcHelpers;
 use properties::ComputedValues;
 use std::ops::{BitAnd, BitOr, BitOrAssign, Not};
-use std::sync::Arc;
+use stylearc::Arc;
 
 /// The representation of Gecko's restyle damage is just a wrapper over
 /// `nsChangeHint`.
diff --git a/components/style/gecko/url.rs b/components/style/gecko/url.rs
index 286094bcb0e..191ae082726 100644
--- a/components/style/gecko/url.rs
+++ b/components/style/gecko/url.rs
@@ -10,8 +10,8 @@ use gecko_bindings::sugar::refptr::RefPtr;
 use parser::ParserContext;
 use std::borrow::Cow;
 use std::fmt::{self, Write};
-use std::sync::Arc;
 use style_traits::ToCss;
+use stylearc::Arc;
 
 /// A specified url() value for gecko. Gecko does not eagerly resolve SpecifiedUrls.
 #[derive(Clone, Debug, PartialEq)]
diff --git a/components/style/gecko/wrapper.rs b/components/style/gecko/wrapper.rs
index 100830c0e0d..f71ef0a6c9c 100644
--- a/components/style/gecko/wrapper.rs
+++ b/components/style/gecko/wrapper.rs
@@ -71,8 +71,8 @@ use std::collections::HashMap;
 use std::fmt;
 use std::hash::{Hash, Hasher};
 use std::ptr;
-use std::sync::Arc;
 use string_cache::{Atom, Namespace, WeakAtom, WeakNamespace};
+use stylearc::Arc;
 use stylesheets::UrlExtraData;
 use stylist::ApplicableDeclarationBlock;
 
diff --git a/components/style/gecko_bindings/sugar/ownership.rs b/components/style/gecko_bindings/sugar/ownership.rs
index abcf5c65a8a..6c4746013b3 100644
--- a/components/style/gecko_bindings/sugar/ownership.rs
+++ b/components/style/gecko_bindings/sugar/ownership.rs
@@ -8,7 +8,7 @@ use std::marker::PhantomData;
 use std::mem::{forget, transmute};
 use std::ops::{Deref, DerefMut};
 use std::ptr;
-use std::sync::Arc;
+use stylearc::Arc;
 
 /// Indicates that a given Servo type has a corresponding Gecko FFI type.
 pub unsafe trait HasFFI : Sized {
diff --git a/components/style/gecko_bindings/sugar/refptr.rs b/components/style/gecko_bindings/sugar/refptr.rs
index 3c3dec9aee3..9ca1d3dc7b6 100644
--- a/components/style/gecko_bindings/sugar/refptr.rs
+++ b/components/style/gecko_bindings/sugar/refptr.rs
@@ -9,7 +9,7 @@ use gecko_bindings::sugar::ownership::HasArcFFI;
 use std::{mem, ptr};
 use std::marker::PhantomData;
 use std::ops::{Deref, DerefMut};
-use std::sync::Arc;
+use stylearc::Arc;
 
 /// Trait for all objects that have Addref() and Release
 /// methods and can be placed inside RefPtr<T>
diff --git a/components/style/keyframes.rs b/components/style/keyframes.rs
index 8113c06bb6c..3a80320bb52 100644
--- a/components/style/keyframes.rs
+++ b/components/style/keyframes.rs
@@ -17,8 +17,8 @@ use properties::animated_properties::TransitionProperty;
 use properties::longhands::transition_timing_function::single_value::SpecifiedValue as SpecifiedTimingFunction;
 use shared_lock::{SharedRwLock, SharedRwLockReadGuard, Locked, ToCssWithGuard};
 use std::fmt;
-use std::sync::Arc;
 use style_traits::ToCss;
+use stylearc::Arc;
 use stylesheets::{CssRuleType, Stylesheet, VendorPrefix};
 
 /// A number from 0 to 1, indicating the percentage of the animation when this
diff --git a/components/style/lib.rs b/components/style/lib.rs
index 99ded2b9fe8..8902ab4efc6 100644
--- a/components/style/lib.rs
+++ b/components/style/lib.rs
@@ -132,7 +132,6 @@ pub mod values;
 pub mod viewport;
 
 use std::fmt;
-use std::sync::Arc;
 use style_traits::ToCss;
 
 #[cfg(feature = "gecko")] pub use gecko_string_cache as string_cache;
@@ -177,14 +176,6 @@ macro_rules! reexport_computed_values {
 }
 longhand_properties_idents!(reexport_computed_values);
 
-/// Returns whether the two arguments point to the same value.
-///
-/// FIXME: Remove this and use Arc::ptr_eq once we require Rust 1.17
-#[inline]
-pub fn arc_ptr_eq<T: 'static>(a: &Arc<T>, b: &Arc<T>) -> bool {
-    ptr_eq::<T>(&**a, &**b)
-}
-
 /// Pointer equality
 ///
 /// FIXME: Remove this and use std::ptr::eq once we require Rust 1.17
diff --git a/components/style/matching.rs b/components/style/matching.rs
index ca2db43c4b9..8da1192d4d3 100644
--- a/components/style/matching.rs
+++ b/components/style/matching.rs
@@ -27,7 +27,7 @@ use selectors::bloom::BloomFilter;
 use selectors::matching::{ElementSelectorFlags, StyleRelations};
 use selectors::matching::AFFECTED_BY_PSEUDO_ELEMENTS;
 use sink::ForgetfulSink;
-use std::sync::Arc;
+use stylearc::Arc;
 use stylist::ApplicableDeclarationBlock;
 
 /// The way a style should be inherited.
@@ -120,8 +120,8 @@ fn same_computed_values<E: TElement>(first: Option<E>, second: Option<E>) -> boo
         _ => return false,
     };
 
-    let eq = ::arc_ptr_eq(a.borrow_data().unwrap().styles().primary.values(),
-                          b.borrow_data().unwrap().styles().primary.values());
+    let eq = Arc::ptr_eq(a.borrow_data().unwrap().styles().primary.values(),
+                         b.borrow_data().unwrap().styles().primary.values());
     eq
 }
 
diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 4643d176949..b428ec3e198 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -61,7 +61,7 @@ use properties::{PropertyDeclaration, PropertyDeclarationBlock, PropertyDeclarat
 use std::fmt::{self, Debug};
 use std::mem::{forget, transmute, zeroed};
 use std::ptr;
-use std::sync::Arc;
+use stylearc::Arc;
 use std::cmp;
 use values::computed::ToComputedValue;
 use values::{Either, Auto, KeyframesName};
diff --git a/components/style/properties/helpers.mako.rs b/components/style/properties/helpers.mako.rs
index 4db19381e1f..3c3bb537320 100644
--- a/components/style/properties/helpers.mako.rs
+++ b/components/style/properties/helpers.mako.rs
@@ -252,7 +252,7 @@
         use properties::{DeclaredValue, LonghandId, LonghandIdSet};
         use properties::{CSSWideKeyword, ComputedValues, PropertyDeclaration};
         use properties::style_structs;
-        use std::sync::Arc;
+        use stylearc::Arc;
         use values::computed::{Context, ToComputedValue};
         use values::{computed, generics, specified};
         use Atom;
@@ -716,7 +716,7 @@
         use properties::{PropertyDeclaration, ParsedDeclaration};
         use properties::{ShorthandId, UnparsedValue, longhands};
         use std::fmt;
-        use std::sync::Arc;
+        use stylearc::Arc;
         use style_traits::ToCss;
 
         pub struct Longhands {
diff --git a/components/style/properties/longhand/svg.mako.rs b/components/style/properties/longhand/svg.mako.rs
index 7a764fbe9f5..45cb125bf33 100644
--- a/components/style/properties/longhand/svg.mako.rs
+++ b/components/style/properties/longhand/svg.mako.rs
@@ -197,7 +197,7 @@ ${helpers.single_keyword("mask-composite",
                           spec="https://drafts.fxtf.org/css-masking/#propdef-mask-image">
     use std::fmt;
     use style_traits::ToCss;
-    use std::sync::Arc;
+    use stylearc::Arc;
     use values::specified::Image;
     use values::specified::url::SpecifiedUrl;
     use values::HasViewportPercentage;
diff --git a/components/style/properties/properties.mako.rs b/components/style/properties/properties.mako.rs
index aba24623855..83ca3e3d4fb 100644
--- a/components/style/properties/properties.mako.rs
+++ b/components/style/properties/properties.mako.rs
@@ -14,7 +14,7 @@ use std::borrow::Cow;
 use std::collections::HashSet;
 use std::fmt;
 use std::ops::Deref;
-use std::sync::Arc;
+use stylearc::Arc;
 
 use app_units::Au;
 #[cfg(feature = "servo")] use cssparser::{Color as CSSParserColor, RGBA};
@@ -178,7 +178,7 @@ pub mod shorthands {
         use cssparser::Parser;
         use parser::ParserContext;
         use properties::{ParsedDeclaration, ShorthandId, UnparsedValue};
-        use std::sync::Arc;
+        use stylearc::Arc;
 
         pub fn parse(context: &ParserContext, input: &mut Parser) -> Result<ParsedDeclaration, ()> {
             // This function is like the parse() that is generated by
@@ -2246,7 +2246,7 @@ pub use self::lazy_static_module::INITIAL_SERVO_VALUES;
 #[allow(missing_docs)]
 mod lazy_static_module {
     use logical_geometry::WritingMode;
-    use std::sync::Arc;
+    use stylearc::Arc;
     use super::{ComputedValues, longhands, style_structs};
 
     /// The initial values for all style structs as defined by the specification.
diff --git a/components/style/rule_tree/mod.rs b/components/style/rule_tree/mod.rs
index fa6acaa92b5..0947198e2da 100644
--- a/components/style/rule_tree/mod.rs
+++ b/components/style/rule_tree/mod.rs
@@ -6,15 +6,14 @@
 
 //! The rule tree.
 
-use arc_ptr_eq;
 #[cfg(feature = "servo")]
 use heapsize::HeapSizeOf;
 use properties::{Importance, PropertyDeclarationBlock};
 use shared_lock::{Locked, StylesheetGuards, SharedRwLockReadGuard};
 use std::io::{self, Write};
 use std::ptr;
-use std::sync::Arc;
 use std::sync::atomic::{AtomicPtr, AtomicUsize, Ordering};
+use stylearc::Arc;
 use stylesheets::StyleRule;
 use thread_state;
 
@@ -65,8 +64,8 @@ impl StyleSource {
     fn ptr_equals(&self, other: &Self) -> bool {
         use self::StyleSource::*;
         match (self, other) {
-            (&Style(ref one), &Style(ref other)) => arc_ptr_eq(one, other),
-            (&Declarations(ref one), &Declarations(ref other)) => arc_ptr_eq(one, other),
+            (&Style(ref one), &Style(ref other)) => Arc::ptr_eq(one, other),
+            (&Declarations(ref one), &Declarations(ref other)) => Arc::ptr_eq(one, other),
             _ => false,
         }
     }
@@ -203,7 +202,7 @@ impl RuleTree {
                 // so let's skip it for now.
                 let is_here_already = match current.get().source.as_ref() {
                     Some(&StyleSource::Declarations(ref already_here)) => {
-                        arc_ptr_eq(pdb, already_here)
+                        Arc::ptr_eq(pdb, already_here)
                     },
                     _ => unreachable!("Replacing non-declarations style?"),
                 };
diff --git a/components/style/selector_parser.rs b/components/style/selector_parser.rs
index 0664483cbe7..0af60279af8 100644
--- a/components/style/selector_parser.rs
+++ b/components/style/selector_parser.rs
@@ -37,7 +37,7 @@ pub use gecko::restyle_damage::GeckoRestyleDamage as RestyleDamage;
 /// A type that represents the previous computed values needed for restyle
 /// damage calculation.
 #[cfg(feature = "servo")]
-pub type PreExistingComputedValues = ::std::sync::Arc<::properties::ServoComputedValues>;
+pub type PreExistingComputedValues = ::stylearc::Arc<::properties::ServoComputedValues>;
 
 /// A type that represents the previous computed values needed for restyle
 /// damage calculation.
diff --git a/components/style/servo/restyle_damage.rs b/components/style/servo/restyle_damage.rs
index 0ad934278c1..1fd7b38cae2 100644
--- a/components/style/servo/restyle_damage.rs
+++ b/components/style/servo/restyle_damage.rs
@@ -11,7 +11,7 @@ use computed_values::display;
 use heapsize::HeapSizeOf;
 use properties::ServoComputedValues;
 use std::fmt;
-use std::sync::Arc;
+use stylearc::Arc;
 
 bitflags! {
     #[doc = "Individual layout actions that may be necessary after restyling."]
diff --git a/components/style/servo/url.rs b/components/style/servo/url.rs
index c59c6bcb0b7..467f7a45715 100644
--- a/components/style/servo/url.rs
+++ b/components/style/servo/url.rs
@@ -9,6 +9,9 @@ use parser::ParserContext;
 use servo_url::ServoUrl;
 use std::borrow::Cow;
 use std::fmt::{self, Write};
+// Note: We use std::sync::Arc rather than stylearc::Arc here because the
+// nonzero optimization is important in keeping the size of SpecifiedUrl below
+// the threshold.
 use std::sync::Arc;
 use style_traits::ToCss;
 
diff --git a/components/style/shared_lock.rs b/components/style/shared_lock.rs
index 2dec153f342..360118d472e 100644
--- a/components/style/shared_lock.rs
+++ b/components/style/shared_lock.rs
@@ -10,7 +10,7 @@ use atomic_refcell::{AtomicRefCell, AtomicRef, AtomicRefMut};
 use parking_lot::RwLock;
 use std::cell::UnsafeCell;
 use std::fmt;
-use std::sync::Arc;
+use stylearc::Arc;
 
 /// A shared read/write lock that can protect multiple objects.
 ///
@@ -149,7 +149,7 @@ impl<T: fmt::Debug> fmt::Debug for Locked<T> {
 impl<T> Locked<T> {
     #[cfg(feature = "servo")]
     fn same_lock_as(&self, lock: &SharedRwLock) -> bool {
-        ::arc_ptr_eq(&self.shared_lock.arc, &lock.arc)
+        Arc::ptr_eq(&self.shared_lock.arc, &lock.arc)
     }
 
     #[cfg(feature = "gecko")]
diff --git a/components/style/stylesheet_set.rs b/components/style/stylesheet_set.rs
index 78e0c9cd558..0cc6f4fbf51 100644
--- a/components/style/stylesheet_set.rs
+++ b/components/style/stylesheet_set.rs
@@ -4,7 +4,7 @@
 
 //! A centralized set of stylesheets for a document.
 
-use std::sync::Arc;
+use stylearc::Arc;
 use stylesheets::Stylesheet;
 
 /// Entry for a StylesheetSet. We don't bother creating a constructor, because
diff --git a/components/style/stylesheets.rs b/components/style/stylesheets.rs
index 97dfce4c51f..36e5a2a936e 100644
--- a/components/style/stylesheets.rs
+++ b/components/style/stylesheets.rs
@@ -36,10 +36,10 @@ use servo_url::ServoUrl;
 use shared_lock::{SharedRwLock, Locked, ToCssWithGuard, SharedRwLockReadGuard};
 use std::cell::Cell;
 use std::fmt;
-use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use str::starts_with_ignore_ascii_case;
 use style_traits::ToCss;
+use stylearc::Arc;
 use stylist::FnvHashMap;
 use supports::SupportsCondition;
 use values::{CustomIdent, KeyframesName};
diff --git a/components/style/stylist.rs b/components/style/stylist.rs
index cda795d559c..5dc3e807374 100644
--- a/components/style/stylist.rs
+++ b/components/style/stylist.rs
@@ -39,8 +39,8 @@ use std::fmt;
 use std::hash::Hash;
 #[cfg(feature = "servo")]
 use std::marker::PhantomData;
-use std::sync::Arc;
 use style_traits::viewport::ViewportConstraints;
+use stylearc::Arc;
 use stylesheets::{CssRule, FontFaceRule, Origin, StyleRule, Stylesheet, UserAgentStylesheets};
 use thread_state;
 use viewport::{self, MaybeNew, ViewportRule};
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index dff56ce8b0f..f53a47f0af7 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -11,7 +11,7 @@ use std::borrow::Cow;
 use std::env;
 use std::fmt::Write;
 use std::ptr;
-use std::sync::{Arc, Mutex};
+use std::sync::Mutex;
 use style::context::{QuirksMode, SharedStyleContext, StyleContext};
 use style::context::{ThreadLocalStyleContext, ThreadLocalStyleContextCreationInfo};
 use style::data::{ElementData, ElementStyles, RestyleData};
@@ -83,6 +83,7 @@ use style::sequential;
 use style::shared_lock::{SharedRwLock, SharedRwLockReadGuard, StylesheetGuards, ToCssWithGuard, Locked};
 use style::string_cache::Atom;
 use style::style_adjuster::StyleAdjuster;
+use style::stylearc::Arc;
 use style::stylesheets::{CssRule, CssRules, CssRuleType, CssRulesHelpers};
 use style::stylesheets::{ImportRule, MediaRule, NamespaceRule, Origin};
 use style::stylesheets::{PageRule, Stylesheet, StyleRule, SupportsRule};
diff --git a/ports/geckolib/stylesheet_loader.rs b/ports/geckolib/stylesheet_loader.rs
index a79aa6e192f..87fdc4d39f3 100644
--- a/ports/geckolib/stylesheet_loader.rs
+++ b/ports/geckolib/stylesheet_loader.rs
@@ -2,12 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use std::sync::Arc;
 use style::gecko_bindings::bindings::Gecko_LoadStyleSheet;
 use style::gecko_bindings::structs::{Loader, ServoStyleSheet};
 use style::gecko_bindings::sugar::ownership::{HasArcFFI, FFIArcHelpers};
 use style::media_queries::MediaList;
 use style::shared_lock::Locked;
+use style::stylearc::Arc;
 use style::stylesheets::{ImportRule, Stylesheet, StylesheetLoader as StyleStylesheetLoader};
 
 pub struct StylesheetLoader(*mut Loader, *mut ServoStyleSheet);
diff --git a/tests/unit/style/keyframes.rs b/tests/unit/style/keyframes.rs
index 4f96b5f88a9..1f3947c5815 100644
--- a/tests/unit/style/keyframes.rs
+++ b/tests/unit/style/keyframes.rs
@@ -2,12 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use std::sync::Arc;
 use style::keyframes::{Keyframe, KeyframesAnimation, KeyframePercentage,  KeyframeSelector};
 use style::keyframes::{KeyframesStep, KeyframesStepValue};
 use style::properties::{PropertyDeclaration, PropertyDeclarationBlock, Importance};
 use style::properties::animated_properties::TransitionProperty;
 use style::shared_lock::SharedRwLock;
+use style::stylearc::Arc;
 use style::values::specified::{LengthOrPercentageOrAuto, NoCalcLength};
 
 #[test]
diff --git a/tests/unit/style/media_queries.rs b/tests/unit/style/media_queries.rs
index 10634a6f134..d538225d9d8 100644
--- a/tests/unit/style/media_queries.rs
+++ b/tests/unit/style/media_queries.rs
@@ -6,13 +6,13 @@ use cssparser::{Parser, SourcePosition};
 use euclid::size::TypedSize2D;
 use servo_url::ServoUrl;
 use std::borrow::ToOwned;
-use std::sync::Arc;
 use style::Atom;
 use style::context::QuirksMode;
 use style::error_reporting::ParseErrorReporter;
 use style::media_queries::*;
 use style::servo::media_queries::*;
 use style::shared_lock::{SharedRwLock, SharedRwLockReadGuard};
+use style::stylearc::Arc;
 use style::stylesheets::{Stylesheet, Origin, CssRule};
 use style::values::specified;
 use style_traits::ToCss;
diff --git a/tests/unit/style/rule_tree/bench.rs b/tests/unit/style/rule_tree/bench.rs
index ed73bd11d6f..68d253b2965 100644
--- a/tests/unit/style/rule_tree/bench.rs
+++ b/tests/unit/style/rule_tree/bench.rs
@@ -5,13 +5,13 @@
 use cssparser::{Parser, SourcePosition};
 use rayon;
 use servo_url::ServoUrl;
-use std::sync::Arc;
 use style::context::QuirksMode;
 use style::error_reporting::ParseErrorReporter;
 use style::media_queries::MediaList;
 use style::properties::{longhands, Importance, PropertyDeclaration, PropertyDeclarationBlock};
 use style::rule_tree::{CascadeLevel, RuleTree, StrongRuleNode, StyleSource};
 use style::shared_lock::SharedRwLock;
+use style::stylearc::Arc;
 use style::stylesheets::{Origin, Stylesheet, CssRule};
 use test::{self, Bencher};
 
diff --git a/tests/unit/style/stylesheets.rs b/tests/unit/style/stylesheets.rs
index 47aa1ea9730..e599e9687ae 100644
--- a/tests/unit/style/stylesheets.rs
+++ b/tests/unit/style/stylesheets.rs
@@ -10,7 +10,6 @@ use selectors::parser::*;
 use servo_atoms::Atom;
 use servo_url::ServoUrl;
 use std::borrow::ToOwned;
-use std::sync::Arc;
 use std::sync::Mutex;
 use std::sync::atomic::AtomicBool;
 use style::context::QuirksMode;
@@ -22,6 +21,7 @@ use style::properties::{CSSWideKeyword, DeclaredValueOwned, PropertyDeclaration,
 use style::properties::longhands;
 use style::properties::longhands::animation_play_state;
 use style::shared_lock::SharedRwLock;
+use style::stylearc::Arc;
 use style::stylesheets::{Origin, Namespaces};
 use style::stylesheets::{Stylesheet, NamespaceRule, CssRule, CssRules, StyleRule, KeyframesRule};
 use style::values::{KeyframesName, CustomIdent};
diff --git a/tests/unit/style/stylist.rs b/tests/unit/style/stylist.rs
index ea89dfde06b..096af2d0006 100644
--- a/tests/unit/style/stylist.rs
+++ b/tests/unit/style/stylist.rs
@@ -6,12 +6,12 @@ use html5ever_atoms::LocalName;
 use selectors::parser::LocalName as LocalNameSelector;
 use selectors::parser::Selector;
 use servo_atoms::Atom;
-use std::sync::Arc;
 use style::properties::{PropertyDeclarationBlock, PropertyDeclaration};
 use style::properties::{longhands, Importance};
 use style::rule_tree::CascadeLevel;
 use style::selector_parser::{SelectorImpl, SelectorParser};
 use style::shared_lock::SharedRwLock;
+use style::stylearc::Arc;
 use style::stylesheets::StyleRule;
 use style::stylist::{Rule, SelectorMap};
 use style::stylist::needs_revalidation;
diff --git a/tests/unit/style/viewport.rs b/tests/unit/style/viewport.rs
index fb29e87debf..ed8b9b527ee 100644
--- a/tests/unit/style/viewport.rs
+++ b/tests/unit/style/viewport.rs
@@ -7,11 +7,11 @@ use euclid::size::TypedSize2D;
 use media_queries::CSSErrorReporterTest;
 use servo_config::prefs::{PREFS, PrefValue};
 use servo_url::ServoUrl;
-use std::sync::Arc;
 use style::context::QuirksMode;
 use style::media_queries::{Device, MediaList, MediaType};
 use style::parser::{LengthParsingMode, Parse, ParserContext};
 use style::shared_lock::SharedRwLock;
+use style::stylearc::Arc;
 use style::stylesheets::{CssRuleType, Stylesheet, Origin};
 use style::values::specified::LengthOrPercentageOrAuto::{self, Auto};
 use style::values::specified::NoCalcLength::{self, ViewportPercentage};