Auto merge of #24750 - servo:register-tool, r=jdm

Use `#![register_tool]` instead of `Registry::register_attribute`

CC https://github.com/rust-lang/rust/pull/66344, https://github.com/rust-lang/rust/issues/66079

44 files changed, 113 insertions, 96 deletions

diff --git a/components/dom_struct/lib.rs b/components/dom_struct/lib.rs
index e7b2b290ce5..ff95e7d838a 100644
--- a/components/dom_struct/lib.rs
+++ b/components/dom_struct/lib.rs
@@ -17,7 +17,7 @@ pub fn dom_struct(args: TokenStream, input: TokenStream) -> TokenStream {
     }
     let attributes = quote! {
         #[derive(DenyPublicFields, DomObject, JSTraceable, MallocSizeOf)]
-        #[must_root]
+        #[unrooted_must_root_lint::must_root]
         #[repr(C)]
     };
 
diff --git a/components/script/canvas_state.rs b/components/script/canvas_state.rs
index 4b47308fa46..76fd9d12caf 100644
--- a/components/script/canvas_state.rs
+++ b/components/script/canvas_state.rs
@@ -53,7 +53,7 @@ use std::fmt;
 use std::str::FromStr;
 use std::sync::Arc;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Clone, JSTraceable, MallocSizeOf)]
 #[allow(dead_code)]
 pub(crate) enum CanvasFillOrStrokeStyle {
@@ -62,7 +62,7 @@ pub(crate) enum CanvasFillOrStrokeStyle {
     Pattern(Dom<CanvasPattern>),
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Clone, JSTraceable, MallocSizeOf)]
 pub(crate) struct CanvasContextState {
     global_alpha: f64,
@@ -103,7 +103,7 @@ impl CanvasContextState {
     }
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub(crate) struct CanvasState {
     #[ignore_malloc_size_of = "Defined in ipc-channel"]
diff --git a/components/script/document_loader.rs b/components/script/document_loader.rs
index ef60cbc2a6c..9e103b91380 100644
--- a/components/script/document_loader.rs
+++ b/components/script/document_loader.rs
@@ -29,7 +29,7 @@ pub enum LoadType {
 /// created via DocumentLoader::fetch_async) are always removed by the time
 /// that the owner is destroyed.
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct LoadBlocker {
     /// The document whose load event is blocked by this object existing.
     doc: Dom<Document>,
diff --git a/components/script/dom/bindings/callback.rs b/components/script/dom/bindings/callback.rs
index 6059d75605a..fe6b8d36d39 100644
--- a/components/script/dom/bindings/callback.rs
+++ b/components/script/dom/bindings/callback.rs
@@ -40,7 +40,7 @@ pub enum ExceptionHandling {
 /// A common base class for representing IDL callback function and
 /// callback interface types.
 #[derive(JSTraceable)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct CallbackObject {
     /// The underlying `JSObject`.
     callback: Heap<*mut JSObject>,
@@ -131,7 +131,7 @@ pub trait CallbackContainer {
 
 /// A common base class for representing IDL callback function types.
 #[derive(JSTraceable, PartialEq)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct CallbackFunction {
     object: CallbackObject,
 }
@@ -159,7 +159,7 @@ impl CallbackFunction {
 
 /// A common base class for representing IDL callback interface types.
 #[derive(JSTraceable, PartialEq)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct CallbackInterface {
     object: CallbackObject,
 }
diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index e660471364e..0a1df6553fa 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -6406,7 +6406,7 @@ class CGDictionary(CGThing):
         derive = ["JSTraceable"]
         mustRoot = ""
         if self.membersNeedTracing():
-            mustRoot = "#[must_root]\n"
+            mustRoot = "#[unrooted_must_root_lint::must_root]\n"
             derive += ["Default"]
 
         return (string.Template(
@@ -6927,7 +6927,8 @@ class CGCallback(CGClass):
                          bases=[ClassBase(baseName)],
                          constructors=self.getConstructors(),
                          methods=realMethods,
-                         decorators="#[derive(JSTraceable, PartialEq)]\n#[allow_unrooted_interior]")
+                         decorators="#[derive(JSTraceable, PartialEq)]\n"
+                                    "#[unrooted_must_root_lint::allow_unrooted_interior]")
 
     def getConstructors(self):
         return [ClassConstructor(
diff --git a/components/script/dom/bindings/refcounted.rs b/components/script/dom/bindings/refcounted.rs
index 8636f910121..ad5be5bb0cf 100644
--- a/components/script/dom/bindings/refcounted.rs
+++ b/components/script/dom/bindings/refcounted.rs
@@ -151,7 +151,7 @@ impl TrustedPromise {
 /// shared among threads for use in asynchronous operations. The underlying
 /// DOM object is guaranteed to live at least as long as the last outstanding
 /// `Trusted<T>` instance.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct Trusted<T: DomObject> {
     /// A pointer to the Rust DOM object of type T, but void to allow
     /// sending `Trusted<T>` between threads, regardless of T's sendability.
diff --git a/components/script/dom/bindings/reflector.rs b/components/script/dom/bindings/reflector.rs
index dc13fca77b0..2b5a4987eb5 100644
--- a/components/script/dom/bindings/reflector.rs
+++ b/components/script/dom/bindings/reflector.rs
@@ -30,7 +30,7 @@ where
 /// A struct to store a reference to the reflector of a DOM object.
 #[allow(unrooted_must_root)]
 #[derive(MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 // If you're renaming or moving this field, update the path in plugins::reflector as well
 pub struct Reflector {
     #[ignore_malloc_size_of = "defined and measured in rust-mozjs"]
diff --git a/components/script/dom/bindings/root.rs b/components/script/dom/bindings/root.rs
index 6e2c883984c..19df89df53f 100644
--- a/components/script/dom/bindings/root.rs
+++ b/components/script/dom/bindings/root.rs
@@ -46,7 +46,7 @@ use style::thread_state;
 
 /// A rooted value.
 #[allow(unrooted_must_root)]
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct Root<T: StableTraceObject> {
     /// The value to root.
     value: T,
@@ -283,7 +283,7 @@ where
 /// on the stack, the `Dom<T>` can point to freed memory.
 ///
 /// This should only be used as a field in other DOM objects.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Dom<T> {
     ptr: ptr::NonNull<T>,
 }
@@ -343,7 +343,7 @@ unsafe impl<T: DomObject> JSTraceable for Dom<T> {
 
 /// An unrooted reference to a DOM object for use in layout. `Layout*Helpers`
 /// traits must be implemented on this.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct LayoutDom<T> {
     ptr: ptr::NonNull<T>,
 }
@@ -463,7 +463,7 @@ impl LayoutDom<Node> {
 ///
 /// This should only be used as a field in other DOM objects; see warning
 /// on `Dom<T>`.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable)]
 pub struct MutDom<T: DomObject> {
     val: UnsafeCell<Dom<T>>,
@@ -518,7 +518,7 @@ impl<T: DomObject + PartialEq> PartialEq<T> for MutDom<T> {
 ///
 /// This should only be used as a field in other DOM objects; see warning
 /// on `Dom<T>`.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable)]
 pub struct MutNullableDom<T: DomObject> {
     ptr: UnsafeCell<Option<Dom<T>>>,
@@ -616,7 +616,7 @@ impl<T: DomObject> MallocSizeOf for MutNullableDom<T> {
 ///
 /// This should only be used as a field in other DOM objects; see warning
 /// on `Dom<T>`.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct DomOnceCell<T: DomObject> {
     ptr: OnceCell<Dom<T>>,
 }
diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 7869d1499ac..65faac1bb95 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -883,7 +883,7 @@ impl<'a, T: JSTraceable + 'static> Drop for RootedTraceable<'a, T> {
 /// If you have GC things like *mut JSObject or JSVal, use rooted!.
 /// If you have an arbitrary number of DomObjects to root, use rooted_vec!.
 /// If you know what you're doing, use this.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct RootedTraceableBox<T: 'static + JSTraceable> {
     ptr: *mut T,
 }
@@ -954,7 +954,7 @@ impl<T: JSTraceable + 'static> Drop for RootedTraceableBox<T> {
 /// iterator of `DomRoot`s, `rooted_vec!(let v <- iterator);`.
 #[allow(unrooted_must_root)]
 #[derive(JSTraceable)]
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct RootableVec<T: JSTraceable> {
     v: Vec<T>,
 }
@@ -967,7 +967,7 @@ impl<T: JSTraceable> RootableVec<T> {
 }
 
 /// A vector of items that are rooted for the lifetime 'a.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct RootedVec<'a, T: 'static + JSTraceable> {
     root: &'a mut RootableVec<T>,
 }
diff --git a/components/script/dom/bindings/weakref.rs b/components/script/dom/bindings/weakref.rs
index bea2141d142..5c74e111816 100644
--- a/components/script/dom/bindings/weakref.rs
+++ b/components/script/dom/bindings/weakref.rs
@@ -34,13 +34,13 @@ pub const DOM_WEAK_SLOT: u32 = 1;
 
 /// A weak reference to a JS-managed DOM object.
 #[allow(unrooted_must_root)]
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct WeakRef<T: WeakReferenceable> {
     ptr: ptr::NonNull<WeakBox<T>>,
 }
 
 /// The inner box of weak references, public for the finalization in codegen.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct WeakBox<T: WeakReferenceable> {
     /// The reference count. When it reaches zero, the `value` field should
     /// have already been set to `None`. The pointee contributes one to the count.
@@ -218,7 +218,7 @@ unsafe impl<T: WeakReferenceable> JSTraceable for MutableWeakRef<T> {
 
 /// A vector of weak references. On tracing, the vector retains
 /// only references which still point to live objects.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 #[derive(MallocSizeOf)]
 pub struct WeakRefVec<T: WeakReferenceable> {
     vec: Vec<WeakRef<T>>,
@@ -268,7 +268,7 @@ impl<T: WeakReferenceable> DerefMut for WeakRefVec<T> {
 
 /// An entry of a vector of weak references. Passed to the closure
 /// given to `WeakRefVec::update`.
-#[allow_unrooted_interior]
+#[unrooted_must_root_lint::allow_unrooted_interior]
 pub struct WeakRefEntry<'a, T: WeakReferenceable> {
     vec: &'a mut WeakRefVec<T>,
     index: &'a mut usize,
diff --git a/components/script/dom/blob.rs b/components/script/dom/blob.rs
index fbf3e5819be..db90b2d2bda 100644
--- a/components/script/dom/blob.rs
+++ b/components/script/dom/blob.rs
@@ -31,7 +31,7 @@ pub struct FileBlob {
 }
 
 /// Different backends of Blob
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable)]
 pub enum BlobImpl {
     /// File-based blob, whose content lives in the net process
diff --git a/components/script/dom/cssstyledeclaration.rs b/components/script/dom/cssstyledeclaration.rs
index d623f46005a..2ad565f9b45 100644
--- a/components/script/dom/cssstyledeclaration.rs
+++ b/components/script/dom/cssstyledeclaration.rs
@@ -39,7 +39,7 @@ pub struct CSSStyleDeclaration {
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub enum CSSStyleOwner {
     Element(Dom<Element>),
     CSSRule(
diff --git a/components/script/dom/customelementregistry.rs b/components/script/dom/customelementregistry.rs
index 64117959500..7b4229835e2 100644
--- a/components/script/dom/customelementregistry.rs
+++ b/components/script/dom/customelementregistry.rs
@@ -706,7 +706,7 @@ pub fn try_upgrade_element(element: &Element) {
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub enum CustomElementReaction {
     Upgrade(#[ignore_malloc_size_of = "Rc"] Rc<CustomElementDefinition>),
     Callback(
@@ -752,7 +752,7 @@ enum BackupElementQueueFlag {
 
 /// <https://html.spec.whatwg.org/multipage/#custom-element-reactions-stack>
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct CustomElementReactionStack {
     stack: DomRefCell<Vec<ElementQueue>>,
     backup_queue: ElementQueue,
@@ -934,7 +934,7 @@ impl CustomElementReactionStack {
 
 /// <https://html.spec.whatwg.org/multipage/#element-queue>
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct ElementQueue {
     queue: DomRefCell<VecDeque<Dom<Element>>>,
 }
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index b2a6468bd90..5a344879005 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -4749,7 +4749,7 @@ impl AnimationFrameCallback {
 }
 
 #[derive(Default, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct PendingInOrderScriptVec {
     scripts: DomRefCell<VecDeque<PendingScript>>,
 }
@@ -4787,7 +4787,7 @@ impl PendingInOrderScriptVec {
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct PendingScript {
     element: Dom<HTMLScriptElement>,
     load: Option<ScriptResult>,
diff --git a/components/script/dom/documentorshadowroot.rs b/components/script/dom/documentorshadowroot.rs
index 594801584c8..724ea11da8c 100644
--- a/components/script/dom/documentorshadowroot.rs
+++ b/components/script/dom/documentorshadowroot.rs
@@ -28,7 +28,7 @@ use style::shared_lock::{SharedRwLock as StyleSharedRwLock, SharedRwLockReadGuar
 use style::stylesheets::{CssRule, Origin, Stylesheet};
 
 #[derive(Clone, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct StyleSheetInDocument {
     #[ignore_malloc_size_of = "Arc"]
     pub sheet: Arc<Stylesheet>,
@@ -76,7 +76,7 @@ impl ::style::stylesheets::StylesheetInDocument for StyleSheetInDocument {
 }
 
 // https://w3c.github.io/webcomponents/spec/shadow/#extensions-to-the-documentorshadowroot-mixin
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub struct DocumentOrShadowRoot {
     window: Dom<Window>,
diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 8924f8ddd1c..89410a6b6b0 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -50,7 +50,7 @@ use style::attr::{AttrValue, LengthOrPercentageOrAuto};
 const DEFAULT_WIDTH: u32 = 300;
 const DEFAULT_HEIGHT: u32 = 150;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Clone, JSTraceable, MallocSizeOf)]
 pub enum CanvasContext {
     Context2d(Dom<CanvasRenderingContext2D>),
diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index 698e21517a8..5b6bd321534 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/components/script/dom/htmlimageelement.rs
@@ -133,7 +133,7 @@ enum ImageRequestPhase {
     Current,
 }
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct ImageRequest {
     state: State,
     parsed_url: Option<ServoUrl>,
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index 60b5cb9bcb1..5fdbad5c1bd 100755
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -237,7 +237,7 @@ pub struct HTMLInputElement {
 }
 
 #[derive(JSTraceable)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(MallocSizeOf)]
 struct InputActivationState {
     indeterminate: bool,
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 13c5cd126c7..5afc2deb381 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -268,7 +268,7 @@ impl FrameRenderer for MediaFrameRenderer {
     }
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 enum SrcObject {
     MediaStream(Dom<MediaStream>),
diff --git a/components/script/dom/messageevent.rs b/components/script/dom/messageevent.rs
index 3e9a7079605..9d9e5f88e35 100644
--- a/components/script/dom/messageevent.rs
+++ b/components/script/dom/messageevent.rs
@@ -26,7 +26,7 @@ use js::jsval::JSVal;
 use js::rust::HandleValue;
 use servo_atoms::Atom;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 enum SrcObject {
     WindowProxy(Dom<WindowProxy>),
diff --git a/components/script/dom/nodelist.rs b/components/script/dom/nodelist.rs
index 82fd3be59d6..930fedbbec4 100644
--- a/components/script/dom/nodelist.rs
+++ b/components/script/dom/nodelist.rs
@@ -13,7 +13,7 @@ use dom_struct::dom_struct;
 use std::cell::Cell;
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub enum NodeListType {
     Simple(Vec<Dom<Node>>),
     Children(ChildrenList),
@@ -119,7 +119,7 @@ impl NodeList {
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct ChildrenList {
     node: Dom<Node>,
     #[ignore_malloc_size_of = "Defined in rust-mozjs"]
diff --git a/components/script/dom/offscreencanvas.rs b/components/script/dom/offscreencanvas.rs
index 69c1114768c..2186ba54bc8 100644
--- a/components/script/dom/offscreencanvas.rs
+++ b/components/script/dom/offscreencanvas.rs
@@ -23,7 +23,7 @@ use ref_filter_map;
 use std::cell::Cell;
 use std::cell::Ref;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Clone, JSTraceable, MallocSizeOf)]
 pub enum OffscreenCanvasContext {
     OffscreenContext2d(Dom<OffscreenCanvasRenderingContext2D>),
diff --git a/components/script/dom/paintworkletglobalscope.rs b/components/script/dom/paintworkletglobalscope.rs
index bc04ab63440..ce3f955cc9c 100644
--- a/components/script/dom/paintworkletglobalscope.rs
+++ b/components/script/dom/paintworkletglobalscope.rs
@@ -473,7 +473,7 @@ pub enum PaintWorkletTask {
 /// This type is dangerous, because it contains uboxed `Heap<JSVal>` values,
 /// which can't be moved.
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct PaintDefinition {
     #[ignore_malloc_size_of = "mozjs"]
     class_constructor: Heap<JSVal>,
diff --git a/components/script/dom/promise.rs b/components/script/dom/promise.rs
index b101c449348..d2e209b98dd 100644
--- a/components/script/dom/promise.rs
+++ b/components/script/dom/promise.rs
@@ -37,7 +37,7 @@ use std::ptr;
 use std::rc::Rc;
 
 #[dom_struct]
-#[allow_unrooted_in_rc]
+#[unrooted_must_root_lint::allow_unrooted_in_rc]
 pub struct Promise {
     reflector: Reflector,
     /// Since Promise values are natively reference counted without the knowledge of
diff --git a/components/script/dom/range.rs b/components/script/dom/range.rs
index 64a26fa0ba9..819cc284d63 100644
--- a/components/script/dom/range.rs
+++ b/components/script/dom/range.rs
@@ -1011,7 +1011,7 @@ impl RangeMethods for Range {
 }
 
 #[derive(DenyPublicFields, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct BoundaryPoint {
     node: MutDom<Node>,
     offset: Cell<u32>,
diff --git a/components/script/dom/raredata.rs b/components/script/dom/raredata.rs
index 8c481425982..e32f218ce89 100644
--- a/components/script/dom/raredata.rs
+++ b/components/script/dom/raredata.rs
@@ -15,7 +15,7 @@ use std::rc::Rc;
 //           storage.
 
 #[derive(Default, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct NodeRareData {
     /// The shadow root the node belongs to.
     /// This is None if the node is not in a shadow tree or
@@ -28,7 +28,7 @@ pub struct NodeRareData {
 }
 
 #[derive(Default, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct ElementRareData {
     /// https://dom.spec.whatwg.org/#dom-element-shadowroot
     /// The ShadowRoot this element is host of.
diff --git a/components/script/dom/servoparser/async_html.rs b/components/script/dom/servoparser/async_html.rs
index 42296062840..6930f2553c5 100644
--- a/components/script/dom/servoparser/async_html.rs
+++ b/components/script/dom/servoparser/async_html.rs
@@ -196,7 +196,7 @@ fn create_buffer_queue(mut buffers: VecDeque<SendTendril<UTF8>>) -> BufferQueue
 //   |_____________|                         |_______________|
 //
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Tokenizer {
     document: Dom<Document>,
     #[ignore_malloc_size_of = "Defined in std"]
diff --git a/components/script/dom/servoparser/html.rs b/components/script/dom/servoparser/html.rs
index c9e3a06f34f..22e2574a9b4 100644
--- a/components/script/dom/servoparser/html.rs
+++ b/components/script/dom/servoparser/html.rs
@@ -30,7 +30,7 @@ use servo_url::ServoUrl;
 use std::io;
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Tokenizer {
     #[ignore_malloc_size_of = "Defined in html5ever"]
     inner: HtmlTokenizer<TreeBuilder<Dom<Node>, Sink>>,
diff --git a/components/script/dom/servoparser/mod.rs b/components/script/dom/servoparser/mod.rs
index 91b5c9bfce6..004daeed9be 100644
--- a/components/script/dom/servoparser/mod.rs
+++ b/components/script/dom/servoparser/mod.rs
@@ -626,7 +626,7 @@ enum ParserKind {
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 enum Tokenizer {
     Html(self::html::Tokenizer),
     AsyncHtml(self::async_html::Tokenizer),
@@ -945,7 +945,7 @@ fn insert(parent: &Node, reference_child: Option<&Node>, child: NodeOrText<Dom<N
 }
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Sink {
     base_url: ServoUrl,
     document: Dom<Document>,
diff --git a/components/script/dom/servoparser/prefetch.rs b/components/script/dom/servoparser/prefetch.rs
index 906c9352771..d9de4d7036f 100644
--- a/components/script/dom/servoparser/prefetch.rs
+++ b/components/script/dom/servoparser/prefetch.rs
@@ -32,7 +32,7 @@ use servo_url::ImmutableOrigin;
 use servo_url::ServoUrl;
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Tokenizer {
     #[ignore_malloc_size_of = "Defined in html5ever"]
     inner: HtmlTokenizer<PrefetchSink>,
diff --git a/components/script/dom/servoparser/xml.rs b/components/script/dom/servoparser/xml.rs
index 8f30e54174d..ac900d61ce0 100644
--- a/components/script/dom/servoparser/xml.rs
+++ b/components/script/dom/servoparser/xml.rs
@@ -17,7 +17,7 @@ use xml5ever::tokenizer::XmlTokenizer;
 use xml5ever::tree_builder::{Tracer as XmlTracer, XmlTreeBuilder};
 
 #[derive(JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Tokenizer {
     #[ignore_malloc_size_of = "Defined in xml5ever"]
     inner: XmlTokenizer<XmlTreeBuilder<Dom<Node>, Sink>>,
diff --git a/components/script/dom/stylesheetlist.rs b/components/script/dom/stylesheetlist.rs
index 236f1c9cd9a..391ac55ed91 100644
--- a/components/script/dom/stylesheetlist.rs
+++ b/components/script/dom/stylesheetlist.rs
@@ -16,7 +16,7 @@ use dom_struct::dom_struct;
 use servo_arc::Arc;
 use style::stylesheets::Stylesheet;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub enum StyleSheetListOwner {
     Document(Dom<Document>),
diff --git a/components/script/dom/trackevent.rs b/components/script/dom/trackevent.rs
index 684a0fcde52..5a734a0e4c9 100644
--- a/components/script/dom/trackevent.rs
+++ b/components/script/dom/trackevent.rs
@@ -20,7 +20,7 @@ use crate::dom::window::Window;
 use dom_struct::dom_struct;
 use servo_atoms::Atom;
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 enum MediaTrack {
     Video(Dom<VideoTrack>),
diff --git a/components/script/dom/webgl_extensions/extensions.rs b/components/script/dom/webgl_extensions/extensions.rs
index fa502ca26cd..b7a2f2beb80 100644
--- a/components/script/dom/webgl_extensions/extensions.rs
+++ b/components/script/dom/webgl_extensions/extensions.rs
@@ -140,7 +140,7 @@ impl WebGLExtensionFeatures {
 }
 
 /// Handles the list of implemented, supported and enabled WebGL extensions.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub struct WebGLExtensions {
     extensions: DomRefCell<HashMap<String, Box<dyn WebGLExtensionWrapper>>>,
diff --git a/components/script/dom/webgl_extensions/wrapper.rs b/components/script/dom/webgl_extensions/wrapper.rs
index 6af68c4678e..bf8db31418c 100644
--- a/components/script/dom/webgl_extensions/wrapper.rs
+++ b/components/script/dom/webgl_extensions/wrapper.rs
@@ -28,7 +28,7 @@ pub trait WebGLExtensionWrapper: JSTraceable + MallocSizeOf {
     fn as_any(&self) -> &dyn Any;
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub struct TypedWebGLExtensionWrapper<T: WebGLExtension> {
     extension: MutNullableDom<T::Extension>,
diff --git a/components/script/dom/webglframebuffer.rs b/components/script/dom/webglframebuffer.rs
index df9e194962e..def5b36a27f 100644
--- a/components/script/dom/webglframebuffer.rs
+++ b/components/script/dom/webglframebuffer.rs
@@ -29,7 +29,7 @@ pub enum CompleteForRendering {
     MissingColorAttachment,
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Clone, JSTraceable, MallocSizeOf)]
 enum WebGLFramebufferAttachment {
     Renderbuffer(Dom<WebGLRenderbuffer>),
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index c843ab578d1..74fd8068a72 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -4275,7 +4275,7 @@ capabilities! {
     STENCIL_TEST,
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable, MallocSizeOf)]
 pub struct Textures {
     active_unit: Cell<u32>,
@@ -4343,7 +4343,7 @@ impl Textures {
     }
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(Default, JSTraceable, MallocSizeOf)]
 struct TextureUnit {
     tex_2d: MutNullableDom<WebGLTexture>,
diff --git a/components/script/dom/webglvertexarrayobjectoes.rs b/components/script/dom/webglvertexarrayobjectoes.rs
index 22d162782d8..e54eaf3f04a 100644
--- a/components/script/dom/webglvertexarrayobjectoes.rs
+++ b/components/script/dom/webglvertexarrayobjectoes.rs
@@ -258,7 +258,7 @@ impl Drop for WebGLVertexArrayObjectOES {
 }
 
 #[derive(Clone, JSTraceable, MallocSizeOf)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct VertexAttribData {
     pub enabled_as_array: bool,
     pub size: u8,
diff --git a/components/script/dom/worklet.rs b/components/script/dom/worklet.rs
index 398710ee558..e882566e07f 100644
--- a/components/script/dom/worklet.rs
+++ b/components/script/dom/worklet.rs
@@ -417,7 +417,7 @@ struct WorkletThreadInit {
 }
 
 /// A thread for executing worklets.
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 struct WorkletThread {
     /// Which role the thread is currently playing
     role: WorkletThreadRole,
diff --git a/components/script/lib.rs b/components/script/lib.rs
index 87eec7cab02..deab92ea107 100644
--- a/components/script/lib.rs
+++ b/components/script/lib.rs
@@ -7,12 +7,14 @@
 #![feature(drain_filter)]
 #![feature(inner_deref)]
 #![feature(plugin)]
+#![feature(register_tool)]
 #![deny(unsafe_code)]
 #![allow(non_snake_case)]
 #![doc = "The script crate contains all matters DOM."]
 #![cfg_attr(not(feature = "unrooted_must_root_lint"), allow(unknown_lints))]
 #![allow(deprecated)] // FIXME: Can we make `allow` only apply to the `plugin` crate attribute?
 #![plugin(script_plugins)]
+#![register_tool(unrooted_must_root_lint)]
 
 #[macro_use]
 extern crate bitflags;
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 20ac88b7bc1..43741209fa1 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -434,7 +434,7 @@ impl OpaqueSender<CommonScriptMsg> for Sender<MainThreadScriptMsg> {
 
 /// The set of all documents managed by this script thread.
 #[derive(JSTraceable)]
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 pub struct Documents {
     map: HashMap<PipelineId, Dom<Document>>,
 }
diff --git a/components/script/serviceworkerjob.rs b/components/script/serviceworkerjob.rs
index 8ba955928a3..93340cabe27 100644
--- a/components/script/serviceworkerjob.rs
+++ b/components/script/serviceworkerjob.rs
@@ -38,7 +38,7 @@ pub enum SettleType {
     Reject(Error),
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable)]
 pub struct Job {
     pub job_type: JobType,
@@ -97,7 +97,7 @@ impl PartialEq for Job {
     }
 }
 
-#[must_root]
+#[unrooted_must_root_lint::must_root]
 #[derive(JSTraceable)]
 pub struct JobQueue(pub DomRefCell<HashMap<ServoUrl, Vec<Job>>>);
 
diff --git a/components/script_plugins/Cargo.toml b/components/script_plugins/Cargo.toml
index c6bc3eb2250..1b86f9cb0b7 100644
--- a/components/script_plugins/Cargo.toml
+++ b/components/script_plugins/Cargo.toml
@@ -11,3 +11,6 @@ plugin = true
 
 [features]
 unrooted_must_root_lint = []
+
+[dependencies]
+matches = "0.1"
diff --git a/components/script_plugins/lib.rs b/components/script_plugins/lib.rs
index 740ae9f35ad..ec05f697e05 100644
--- a/components/script_plugins/lib.rs
+++ b/components/script_plugins/lib.rs
@@ -8,9 +8,9 @@
 //!
 //!  - `#[derive(DenyPublicFields)]` : Forces all fields in a struct/enum to be private
 //!  - `#[derive(JSTraceable)]` : Auto-derives an implementation of `JSTraceable` for a struct in the script crate
-//!  - `#[must_root]` : Prevents data of the marked type from being used on the stack.
+//!  - `#[unrooted_must_root_lint::must_root]` : Prevents data of the marked type from being used on the stack.
 //!                     See the lints module for more details
-//!  - `#[dom_struct]` : Implies #[derive(JSTraceable, DenyPublicFields)]`, and `#[must_root]`.
+//!  - `#[dom_struct]` : Implies #[derive(JSTraceable, DenyPublicFields)]`, and `#[unrooted_must_root_lint::must_root]`.
 //!                       Use this for structs that correspond to a DOM type
 
 #![deny(unsafe_code)]
@@ -20,6 +20,8 @@
 #![cfg(feature = "unrooted_must_root_lint")]
 
 #[macro_use]
+extern crate matches;
+#[macro_use]
 extern crate rustc;
 extern crate rustc_driver;
 extern crate syntax;
@@ -30,7 +32,7 @@ use rustc::hir::{self, ExprKind, HirId};
 use rustc::lint::{LateContext, LateLintPass, LintContext, LintPass};
 use rustc::ty;
 use rustc_driver::plugin::Registry;
-use syntax::feature_gate::AttributeType::Whitelisted;
+use syntax::ast::{AttrKind, Attribute};
 use syntax::source_map;
 use syntax::source_map::{ExpnKind, MacroKind, Span};
 use syntax::symbol::sym;
@@ -44,9 +46,6 @@ pub fn plugin_registrar(reg: &mut Registry) {
 
 fn registrar(reg: &mut Registry) {
     let symbols = Symbols::new();
-    reg.register_attribute(symbols.allow_unrooted_interior, Whitelisted);
-    reg.register_attribute(symbols.allow_unrooted_in_rc, Whitelisted);
-    reg.register_attribute(symbols.must_root, Whitelisted);
     reg.lint_store.register_lints(&[&UNROOTED_MUST_ROOT]);
     reg.lint_store
         .register_late_pass(move || Box::new(UnrootedPass::new(symbols.clone())));
@@ -60,12 +59,12 @@ declare_lint!(
 
 /// Lint for ensuring safe usage of unrooted pointers
 ///
-/// This lint (disable with `-A unrooted-must-root`/`#[allow(unrooted_must_root)]`) ensures that `#[must_root]`
-/// values are used correctly.
+/// This lint (disable with `-A unrooted-must-root`/`#[allow(unrooted_must_root)]`) ensures that
+/// `#[unrooted_must_root_lint::must_root]` values are used correctly.
 ///
 /// "Incorrect" usage includes:
 ///
-///  - Not being used in a struct/enum field which is not `#[must_root]` itself
+///  - Not being used in a struct/enum field which is not `#[unrooted_must_root_lint::must_root]` itself
 ///  - Not being used as an argument to a function (Except onces named `new` and `new_inherited`)
 ///  - Not being bound locally in a `let` statement, assignment, `for` loop, or `match` statement.
 ///
@@ -74,7 +73,7 @@ declare_lint!(
 ///
 /// Structs which have their own mechanism of rooting their unrooted contents (e.g. `ScriptThread`)
 /// can be marked as `#[allow(unrooted_must_root)]`. Smart pointers which root their interior type
-/// can be marked as `#[allow_unrooted_interior]`
+/// can be marked as `#[unrooted_must_root_lint::allow_unrooted_interior]`
 pub(crate) struct UnrootedPass {
     symbols: Symbols,
 }
@@ -85,22 +84,35 @@ impl UnrootedPass {
     }
 }
 
+fn has_lint_attr(sym: &Symbols, attrs: &[Attribute], name: Symbol) -> bool {
+    attrs.iter().any(|attr| {
+        matches!(
+            &attr.kind,
+            AttrKind::Normal(attr_item)
+            if attr_item.path.segments.len() == 2 &&
+            attr_item.path.segments[0].ident.name == sym.unrooted_must_root_lint &&
+            attr_item.path.segments[1].ident.name == name
+        )
+    })
+}
+
 /// Checks if a type is unrooted or contains any owned unrooted types
 fn is_unrooted_ty(sym: &Symbols, cx: &LateContext, ty: &ty::TyS, in_new_function: bool) -> bool {
     let mut ret = false;
     ty.maybe_walk(|t| {
         match t.kind {
             ty::Adt(did, substs) => {
-                if cx.tcx.has_attr(did.did, sym.must_root) {
+                let has_attr = |did, name| has_lint_attr(sym, &cx.tcx.get_attrs(did), name);
+                if has_attr(did.did, sym.must_root) {
                     ret = true;
                     false
-                } else if cx.tcx.has_attr(did.did, sym.allow_unrooted_interior) {
+                } else if has_attr(did.did, sym.allow_unrooted_interior) {
                     false
                 } else if match_def_path(cx, did.did, &[sym.alloc, sym.rc, sym.Rc]) {
                     // Rc<Promise> is okay
                     let inner = substs.type_at(0);
                     if let ty::Adt(did, _) = inner.kind {
-                        if cx.tcx.has_attr(did.did, sym.allow_unrooted_in_rc) {
+                        if has_attr(did.did, sym.allow_unrooted_in_rc) {
                             false
                         } else {
                             true
@@ -175,35 +187,33 @@ impl LintPass for UnrootedPass {
 }
 
 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnrootedPass {
-    /// All structs containing #[must_root] types must be #[must_root] themselves
+    /// All structs containing #[unrooted_must_root_lint::must_root] types
+    /// must be #[unrooted_must_root_lint::must_root] themselves
     fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx hir::Item) {
-        if item
-            .attrs
-            .iter()
-            .any(|a| a.check_name(self.symbols.must_root))
-        {
+        if has_lint_attr(&self.symbols, &item.attrs, self.symbols.must_root) {
             return;
         }
         if let hir::ItemKind::Struct(def, ..) = &item.kind {
             for ref field in def.fields() {
                 let def_id = cx.tcx.hir().local_def_id(field.hir_id);
                 if is_unrooted_ty(&self.symbols, cx, cx.tcx.type_of(def_id), false) {
-                    cx.span_lint(UNROOTED_MUST_ROOT, field.span,
-                                 "Type must be rooted, use #[must_root] on the struct definition to propagate")
+                    cx.span_lint(
+                        UNROOTED_MUST_ROOT,
+                        field.span,
+                        "Type must be rooted, use #[unrooted_must_root_lint::must_root] \
+                         on the struct definition to propagate",
+                    )
                 }
             }
         }
     }
 
-    /// All enums containing #[must_root] types must be #[must_root] themselves
+    /// All enums containing #[unrooted_must_root_lint::must_root] types
+    /// must be #[unrooted_must_root_lint::must_root] themselves
     fn check_variant(&mut self, cx: &LateContext, var: &hir::Variant) {
         let ref map = cx.tcx.hir();
-        if map
-            .expect_item(map.get_parent_item(var.id))
-            .attrs
-            .iter()
-            .all(|a| !a.check_name(self.symbols.must_root))
-        {
+        let parent_item = map.expect_item(map.get_parent_item(var.id));
+        if !has_lint_attr(&self.symbols, &parent_item.attrs, self.symbols.must_root) {
             match var.data {
                 hir::VariantData::Tuple(ref fields, ..) => {
                     for ref field in fields {
@@ -212,7 +222,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnrootedPass {
                             cx.span_lint(
                                 UNROOTED_MUST_ROOT,
                                 field.ty.span,
-                                "Type must be rooted, use #[must_root] on \
+                                "Type must be rooted, use #[unrooted_must_root_lint::must_root] on \
                                  the enum definition to propagate",
                             )
                         }
@@ -222,7 +232,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnrootedPass {
             }
         }
     }
-    /// Function arguments that are #[must_root] types are not allowed
+    /// Function arguments that are #[unrooted_must_root_lint::must_root] types are not allowed
     fn check_fn(
         &mut self,
         cx: &LateContext<'a, 'tcx>,
@@ -291,7 +301,7 @@ impl<'a, 'b, 'tcx> visit::Visitor<'tcx> for FnDefVisitor<'a, 'b, 'tcx> {
         };
 
         match expr.kind {
-            // Trait casts from #[must_root] types are not allowed
+            // Trait casts from #[unrooted_must_root_lint::must_root] types are not allowed
             ExprKind::Cast(ref subexpr, _) => require_rooted(cx, self.in_new_function, &*subexpr),
             // This catches assignments... the main point of this would be to catch mutable
             // references to `JS<T>`.
@@ -393,6 +403,7 @@ macro_rules! symbols {
 }
 
 symbols! {
+    unrooted_must_root_lint
     allow_unrooted_interior
     allow_unrooted_in_rc
     must_root