1 files changed, 35 insertions, 14 deletions

diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 7b7cfe5eea0..a4a83712a08 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -25,7 +25,7 @@
 use self::AttributeType::*;
 use self::AttributeGate::*;
 
-use abi::Abi;
+use rustc_target::spec::abi::Abi;
 use ast::{self, NodeId, PatKind, RangeEnd};
 use attr;
 use edition::{ALL_EDITIONS, Edition};
@@ -272,6 +272,9 @@ declare_features! (
     // Allows cfg(target_has_atomic = "...").
     (active, cfg_target_has_atomic, "1.9.0", Some(32976), None),
 
+    // The `!` type. Does not imply exhaustive_patterns (below) any more.
+    (active, never_type, "1.13.0", Some(35121), None),
+
     // Allows exhaustive pattern matching on types that contain uninhabited types.
     (active, exhaustive_patterns, "1.13.0", None, None),
 
@@ -372,9 +375,6 @@ declare_features! (
     // Future-proofing enums/structs with #[non_exhaustive] attribute (RFC 2008)
     (active, non_exhaustive, "1.22.0", Some(44109), None),
 
-    // Trait object syntax with `dyn` prefix
-    (active, dyn_trait, "1.22.0", Some(44662), Some(Edition::Edition2018)),
-
     // `crate` as visibility modifier, synonymous to `pub(crate)`
     (active, crate_visibility_modifier, "1.23.0", Some(45388), Some(Edition::Edition2018)),
 
@@ -451,6 +451,18 @@ declare_features! (
     (active, mmx_target_feature, "1.27.0", None, None),
     (active, sse4a_target_feature, "1.27.0", None, None),
     (active, tbm_target_feature, "1.27.0", None, None),
+
+    // Allows macro invocations of the form `#[foo::bar]`
+    (active, proc_macro_path_invoc, "1.27.0", None, None),
+
+    // Allows macro invocations on modules expressions and statements and
+    // procedural macros to expand to non-items.
+    (active, proc_macro_mod, "1.27.0", None, None),
+    (active, proc_macro_expr, "1.27.0", None, None),
+    (active, proc_macro_non_items, "1.27.0", None, None),
+
+    // #[doc(alias = "...")]
+    (active, doc_alias, "1.27.0", Some(50146), None),
 );
 
 declare_features! (
@@ -577,6 +589,8 @@ declare_features! (
     (accepted, cfg_target_feature, "1.27.0", Some(29717), None),
     // Allows #[target_feature(...)]
     (accepted, target_feature, "1.27.0", None, None),
+    // Trait object syntax with `dyn` prefix
+    (accepted, dyn_trait, "1.27.0", Some(44662), None),
 );
 
 // If you change this, please modify src/doc/unstable-book as well. You must
@@ -921,7 +935,7 @@ pub const BUILTIN_ATTRIBUTES: &'static [(&'static str, AttributeType, AttributeG
                                  "the `#[naked]` attribute \
                                   is an experimental feature",
                                  cfg_fn!(naked_functions))),
-    ("target_feature", Normal, Ungated),
+    ("target_feature", Whitelisted, Ungated),
     ("export_name", Whitelisted, Ungated),
     ("inline", Whitelisted, Ungated),
     ("link", Whitelisted, Ungated),
@@ -1227,10 +1241,9 @@ fn leveled_feature_err<'a>(sess: &'a ParseSess, feature: &str, span: Span, issue
         GateIssue::Library(lib) => lib,
     };
 
-    let explanation = if let Some(n) = issue {
-        format!("{} (see issue #{})", explain, n)
-    } else {
-        explain.to_owned()
+    let explanation = match issue {
+        None | Some(0) => explain.to_owned(),
+        Some(n) => format!("{} (see issue #{})", explain, n)
     };
 
     let mut err = match level {
@@ -1446,6 +1459,10 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                     gate_feature_post!(&self, doc_spotlight, attr.span,
                         "#[doc(spotlight)] is experimental"
                     );
+                } else if content.iter().any(|c| c.check_name("alias")) {
+                    gate_feature_post!(&self, doc_alias, attr.span,
+                        "#[doc(alias = \"...\")] is experimental"
+                    );
                 }
             }
         }
@@ -1635,9 +1652,9 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             ast::TyKind::BareFn(ref bare_fn_ty) => {
                 self.check_abi(bare_fn_ty.abi, ty.span);
             }
-            ast::TyKind::TraitObject(_, ast::TraitObjectSyntax::Dyn) => {
-                gate_feature_post!(&self, dyn_trait, ty.span,
-                                   "`dyn Trait` syntax is unstable");
+            ast::TyKind::Never => {
+                gate_feature_post!(&self, never_type, ty.span,
+                                   "The `!` type is experimental");
             }
             _ => {}
         }
@@ -1745,8 +1762,8 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                 }
             }
             ast::TraitItemKind::Type(_, ref default) => {
-                // We use two if statements instead of something like match guards so that both
-                // of these errors can be emitted if both cases apply.
+                // We use three if statements instead of something like match guards so that all
+                // of these errors can be emitted if all cases apply.
                 if default.is_some() {
                     gate_feature_post!(&self, associated_type_defaults, ti.span,
                                        "associated type defaults are unstable");
@@ -1755,6 +1772,10 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
                     gate_feature_post!(&self, generic_associated_types, ti.span,
                                        "generic associated types are unstable");
                 }
+                if !ti.generics.where_clause.predicates.is_empty() {
+                    gate_feature_post!(&self, generic_associated_types, ti.span,
+                                       "where clauses on associated types are unstable");
+                }
             }
             _ => {}
         }