Fix warning

Amanieu · Amanieu · commit 03db6f4b4da7 · 2018-11-26T17:51:15.000+01:00
diff --git a/src/libstd/collections/hash/map.rs b/src/libstd/collections/hash/map.rs
@@ -409,7 +409,7 @@ impl<K, V, S> HashMap<K, V, S>
     /// map.try_reserve(10).expect("why is the test harness OOMing on 10 bytes?");
     /// ```
     #[unstable(feature = "try_reserve", reason = "new API", issue="48043")]
-    pub fn try_reserve(&mut self, additional: usize) -> Result<(), CollectionAllocErr> {
+    pub fn try_reserve(&mut self, _additional: usize) -> Result<(), CollectionAllocErr> {
         unimplemented!()
     }
 

Original file line number	Diff line number	Diff line change
`@@ -409,7 +409,7 @@ impl<K, V, S> HashMap<K, V, S>`
`409`	`409`	`/// map.try_reserve(10).expect("why is the test harness OOMing on 10 bytes?");`
`410`	`410`	/// ```
`411`	`411`	`#[unstable(feature = "try_reserve", reason = "new API", issue="48043")]`
`412`		`- pub fn try_reserve(&mut self, additional: usize) -> Result<(), CollectionAllocErr> {`
	`412`	`+ pub fn try_reserve(&mut self, _additional: usize) -> Result<(), CollectionAllocErr> {`
`413`	`413`	`unimplemented!()`
`414`	`414`	`}`
`415`	`415`