Arc should not be Traceable (#561)

gmorenz · web-flow · commit 99518a4cdf23 · 2025-03-06T03:34:41.000Z
Traceable works under the assumption that only one thread will be
looking at values. The entire purpose of `Arc` is to share things
between threads. This ~never works (unless the Arc could be replaced by
a Rc).

Nothing in this crate or servo uses this impl. Let's just delete this.

Signed-off-by: Greg Morenz &lt;greg-morenz@droid.cafe&gt;
diff --git a/mozjs-sys/src/trace.rs b/mozjs-sys/src/trace.rs
@@ -138,13 +138,6 @@ unsafe impl<T: Traceable> Traceable for Rc<T> {
     }
 }
 
-unsafe impl<T: Traceable> Traceable for Arc<T> {
-    #[inline]
-    unsafe fn trace(&self, trc: *mut JSTracer) {
-        (**self).trace(trc);
-    }
-}
-
 unsafe impl<T: Traceable + ?Sized> Traceable for Box<T> {
     #[inline]
     unsafe fn trace(&self, trc: *mut JSTracer) {

Original file line number	Diff line number	Diff line change
`@@ -138,13 +138,6 @@ unsafe impl<T: Traceable> Traceable for Rc<T> {`
`138`	`138`	`}`
`139`	`139`	`}`
`140`	`140`
`141`		`-unsafe impl<T: Traceable> Traceable for Arc<T> {`
`142`		`- #[inline]`
`143`		`- unsafe fn trace(&self, trc: *mut JSTracer) {`
`144`		`- (**self).trace(trc);`
`145`		`- }`
`146`		`-}`
`147`		`-`
`148`	`141`	`unsafe impl<T: Traceable + ?Sized> Traceable for Box<T> {`
`149`	`142`	`#[inline]`
`150`	`143`	`unsafe fn trace(&self, trc: *mut JSTracer) {`