Rollup merge of rust-lang#81730 - RustyYato:object-safe-allocator, r=Amanieu

m-ou-se · web-flow · commit c0a8aae48362 · 2021-02-05T12:26:05.000+01:00
Make `Allocator` object-safe This allows rust-lang/wg-allocators#83: polymorphic allocators
diff --git a/core/src/alloc/mod.rs b/core/src/alloc/mod.rs
@@ -342,7 +342,10 @@ pub unsafe trait Allocator {
     ///
     /// The returned adaptor also implements `Allocator` and will simply borrow this.
     #[inline(always)]
-    fn by_ref(&self) -> &Self {
+    fn by_ref(&self) -> &Self
+    where
+        Self: Sized,
+    {
         self
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -342,7 +342,10 @@ pub unsafe trait Allocator {`
`342`	`342`	`///`
`343`	`343`	/// The returned adaptor also implements `Allocator` and will simply borrow this.
`344`	`344`	`#[inline(always)]`
`345`		`- fn by_ref(&self) -> &Self {`
	`345`	`+ fn by_ref(&self) -> &Self`
	`346`	`+ where`
	`347`	`+ Self: Sized,`
	`348`	`+ {`
`346`	`349`	`self`
`347`	`350`	`}`
`348`	`351`	`}`