stabilize transparent_enums

Author: Centril

src/doc/unstable-book/src/language-features/transparent-enums.md

@@ -257,6 +257,8 @@ declare_features! (
     /// Allows relaxing the coherence rules such that
     /// `impl<T> ForeignTrait<LocalType> for ForeignType<T>` is permitted.
     (accepted, re_rebalance_coherence, "1.41.0", Some(55437), None),
+    /// Allows #[repr(transparent)] on univariant enums (RFC 2645).
+    (accepted, transparent_enums, "1.42.0", Some(60405), None),
     /// Allows using subslice patterns, `[a, .., b]` and `[a, xs @ .., b]`.
     (accepted, slice_patterns, "1.42.0", Some(62254), None),
 

src/librustc_feature/accepted.rs

@@ -468,9 +468,6 @@ declare_features! (
     /// Allows `if/while p && let q = r && ...` chains.
     (active, let_chains, "1.37.0", Some(53667), None),
 
-    /// Allows #[repr(transparent)] on enums (RFC 2645).
-    (active, transparent_enums, "1.37.0", Some(60405), None),
-
     /// Allows #[repr(transparent)] on unions (RFC 2645).
     (active, transparent_unions, "1.37.0", Some(60405), None),
 

src/librustc_feature/active.rs

@@ -2433,16 +2433,6 @@ fn check_transparent(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
     }
     let sp = tcx.sess.source_map().def_span(sp);
 
-    if adt.is_enum() && !tcx.features().transparent_enums {
-        feature_err(
-            &tcx.sess.parse_sess,
-            sym::transparent_enums,
-            sp,
-            "transparent enums are unstable",
-        )
-        .emit();
-    }
-
     if adt.is_union() && !tcx.features().transparent_unions {
         feature_err(
             &tcx.sess.parse_sess,

src/librustc_typeck/check/mod.rs

@@ -10,7 +10,7 @@
 // ignore-windows
 // See repr-transparent.rs
 
-#![feature(transparent_enums, transparent_unions)]
+#![feature(transparent_unions)]
 
 #![crate_type="lib"]
 

src/test/codegen/repr-transparent-aggregates-1.rs

@@ -13,7 +13,7 @@
 // ignore-x86_64
 // See repr-transparent.rs
 
-#![feature(transparent_enums, transparent_unions)]
+#![feature(transparent_unions)]
 
 #![crate_type="lib"]
 

src/test/codegen/repr-transparent-aggregates-2.rs

@@ -3,7 +3,7 @@
 // only-mips64
 // See repr-transparent.rs
 
-#![feature(transparent_enums, transparent_unions)]
+#![feature(transparent_unions)]
 
 #![crate_type="lib"]
 

src/test/codegen/repr-transparent-aggregates-3.rs

@@ -1,7 +1,7 @@
 // compile-flags: -C no-prepopulate-passes
 
 #![crate_type="lib"]
-#![feature(repr_simd, transparent_enums, transparent_unions)]
+#![feature(repr_simd, transparent_unions)]
 
 use std::marker::PhantomData;
 

src/test/codegen/repr-transparent.rs

@@ -1,4 +1,4 @@
-#![feature(transparent_enums, transparent_unions)]
+#![feature(transparent_unions)]
 #![feature(ptr_internals)]
 #![deny(improper_ctypes)]
 #![allow(dead_code)]

src/test/ui/feature-gates/feature-gate-transparent_enums.rs

@@ -3,7 +3,7 @@
 // - repr-transparent-other-reprs.rs
 // - repr-transparent-other-items.rs
 
-#![feature(repr_align, transparent_enums, transparent_unions)]
+#![feature(transparent_unions)]
 
 use std::marker::PhantomData;