pre-expansion gate crate_visibility_modifier

src/libsyntax/feature_gate/check.rs

@@ -652,14 +652,6 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
         }
         visit::walk_impl_item(self, ii)
     }
-
-    fn visit_vis(&mut self, vis: &'a ast::Visibility) {
-        if let ast::VisibilityKind::Crate(ast::CrateSugar::JustCrate) = vis.node {
-            gate_feature_post!(&self, crate_visibility_modifier, vis.span,
-                               "`crate` visibility modifier is experimental");
-        }
-        visit::walk_vis(self, vis)
-    }
 }
 
 pub fn get_features(span_handler: &Handler, krate_attrs: &[ast::Attribute],
@@ -847,6 +839,7 @@ pub fn check_crate(krate: &ast::Crate,
     gate_all!(const_extern_fn, "`const extern fn` definitions are unstable");
     gate_all!(trait_alias, "trait aliases are experimental");
     gate_all!(associated_type_bounds, "associated type bounds are unstable");
+    gate_all!(crate_visibility_modifier, "`crate` visibility modifier is experimental");
 
     visit::walk_crate(&mut visitor, krate);
 }

src/libsyntax/parse/parser.rs

@@ -1122,6 +1122,7 @@ impl<'a> Parser<'a> {
         self.expected_tokens.push(TokenType::Keyword(kw::Crate));
         if self.is_crate_vis() {
             self.bump(); // `crate`
+            self.sess.gated_spans.crate_visibility_modifier.borrow_mut().push(self.prev_span);
             return Ok(respan(self.prev_span, VisibilityKind::Crate(CrateSugar::JustCrate)));
         }
 

src/libsyntax/sess.rs

@@ -34,6 +34,8 @@ crate struct GatedSpans {
     pub trait_alias: Lock<Vec<Span>>,
     /// Spans collected for gating `associated_type_bounds`, e.g. `Iterator<Item: Ord>`.
     pub associated_type_bounds: Lock<Vec<Span>>,
+    /// Spans collected for gating `crate_visibility_modifier`, e.g. `crate fn`.
+    pub crate_visibility_modifier: Lock<Vec<Span>>,
 }
 
 /// Info about a parsing session.

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

@@ -5,4 +5,7 @@ crate struct Bender { //~ ERROR `crate` visibility modifier is experimental
     water: bool,
 }
 
+macro_rules! accept_vis { ($v:vis) => {} }
+accept_vis!(crate);  //~ ERROR `crate` visibility modifier is experimental
+
 fn main() {}

src/test/ui/feature-gates/feature-gate-crate_visibility_modifier.stderr

@@ -7,6 +7,15 @@ LL | crate struct Bender {
    = note: for more information, see https://github.com/rust-lang/rust/issues/53120
    = help: add `#![feature(crate_visibility_modifier)]` to the crate attributes to enable
 
-error: aborting due to previous error
+error[E0658]: `crate` visibility modifier is experimental
+  --> $DIR/feature-gate-crate_visibility_modifier.rs:9:13
+   |
+LL | accept_vis!(crate);
+   |             ^^^^^
+   |
+   = note: for more information, see https://github.com/rust-lang/rust/issues/53120
+   = help: add `#![feature(crate_visibility_modifier)]` to the crate attributes to enable
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0658`.