remove no longer needd UnstableFeature type

compiler/rustc_feature/src/lib.rs

@@ -94,8 +94,8 @@ impl UnstableFeatures {
 
 fn find_lang_feature_issue(feature: Symbol) -> Option<NonZero<u32>> {
     // Search in all the feature lists.
-    if let Some(f) = UNSTABLE_FEATURES.iter().find(|f| f.feature.name == feature) {
-        return f.feature.issue;
+    if let Some(f) = UNSTABLE_FEATURES.iter().find(|f| f.name == feature) {
+        return f.issue;
     }
     if let Some(f) = ACCEPTED_FEATURES.iter().find(|f| f.name == feature) {
         return f.issue;

compiler/rustc_feature/src/unstable.rs

@@ -6,10 +6,6 @@ use rustc_span::symbol::{Symbol, sym};
 
 use super::{Feature, to_nonzero};
 
-pub struct UnstableFeature {
-    pub feature: Feature,
-}
-
 #[derive(PartialEq)]
 enum FeatureStatus {
     Default,
@@ -82,13 +78,11 @@ macro_rules! declare_features {
     )+) => {
         /// Unstable language features that are being implemented or being
         /// considered for acceptance (stabilization) or removal.
-        pub const UNSTABLE_FEATURES: &[UnstableFeature] = &[
-            $(UnstableFeature {
-                feature: Feature {
-                    name: sym::$feature,
-                    since: $ver,
-                    issue: to_nonzero($issue),
-                },
+        pub const UNSTABLE_FEATURES: &[Feature] = &[
+            $(Feature {
+                name: sym::$feature,
+                since: $ver,
+                issue: to_nonzero($issue),
             }),+
         ];