replaces few consts with statics to reduce readonly section

compiler/rustc_feature/src/accepted.rs

@@ -9,7 +9,7 @@ macro_rules! declare_features {
         $(#[doc = $doc:tt])* (accepted, $feature:ident, $ver:expr, $issue:expr),
     )+) => {
         /// Formerly unstable features that have now been accepted (stabilized).
-        pub const ACCEPTED_LANG_FEATURES: &[Feature] = &[
+        pub static ACCEPTED_LANG_FEATURES: &[Feature] = &[
             $(Feature {
                 name: sym::$feature,
                 since: $ver,

compiler/rustc_feature/src/builtin_attrs.rs

@@ -317,7 +317,7 @@ pub struct BuiltinAttribute {
 
 /// Attributes that have a special meaning to rustc or rustdoc.
 #[rustfmt::skip]
-pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
+pub static BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     // ==========================================================================
     // Stable attributes:
     // ==========================================================================

compiler/rustc_feature/src/removed.rs

@@ -14,7 +14,7 @@ macro_rules! declare_features {
         $(#[doc = $doc:tt])* (removed, $feature:ident, $ver:expr, $issue:expr, $reason:expr),
     )+) => {
         /// Formerly unstable features that have now been removed.
-        pub const REMOVED_LANG_FEATURES: &[RemovedFeature] = &[
+        pub static REMOVED_LANG_FEATURES: &[RemovedFeature] = &[
             $(RemovedFeature {
                 feature: Feature {
                     name: sym::$feature,

compiler/rustc_feature/src/unstable.rs

@@ -104,7 +104,7 @@ macro_rules! declare_features {
     )+) => {
         /// Unstable language features that are being implemented or being
         /// considered for acceptance (stabilization) or removal.
-        pub const UNSTABLE_LANG_FEATURES: &[Feature] = &[
+        pub static UNSTABLE_LANG_FEATURES: &[Feature] = &[
             $(Feature {
                 name: sym::$feature,
                 since: $ver,