legacy-ctor-visibility -> hard error

Author: Centril

src/doc/rustc/src/lints/listing/deny-by-default.md

@@ -45,41 +45,6 @@ error: defaults for type parameters are only allowed in `struct`, `enum`, `type`
   = note: for more information, see issue #36887 <https://github.com/rust-lang/rust/issues/36887>
 ```
 
-## legacy-constructor-visibility
-
-[RFC 1506](https://github.com/rust-lang/rfcs/blob/master/text/1506-adt-kinds.md) modified some
-visibility rules, and changed the visibility of struct constructors. Some
-example code that triggers this lint:
-
-```rust,ignore
-mod m {
-    pub struct S(u8);
-    
-    fn f() {
-        // this is trying to use S from the 'use' line, but because the `u8` is
-        // not pub, it is private
-        ::S;
-    }
-}
-
-use m::S;
-```
-
-This will produce:
-
-```text
-error: private struct constructors are not usable through re-exports in outer modules
- --> src/main.rs:5:9
-  |
-5 |         ::S;
-  |         ^^^
-  |
-  = note: `#[deny(legacy_constructor_visibility)]` on by default
-  = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-  = note: for more information, see issue #39207 <https://github.com/rust-lang/rust/issues/39207>
-```
-
-
 ## legacy-directory-ownership
 
 The legacy_directory_ownership warning is issued when

src/librustc/lint/builtin.rs

@@ -176,12 +176,6 @@ declare_lint! {
      not named `mod.rs`"
 }
 
-declare_lint! {
-    pub LEGACY_CONSTRUCTOR_VISIBILITY,
-    Deny,
-    "detects use of struct constructors that would be invisible with new visibility rules"
-}
-
 declare_lint! {
     pub MISSING_FRAGMENT_SPECIFIER,
     Deny,
@@ -427,7 +421,6 @@ declare_lint_pass! {
         SAFE_PACKED_BORROWS,
         PATTERNS_IN_FNS_WITHOUT_BODY,
         LEGACY_DIRECTORY_OWNERSHIP,
-        LEGACY_CONSTRUCTOR_VISIBILITY,
         MISSING_FRAGMENT_SPECIFIER,
         PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES,
         LATE_BOUND_LIFETIME_ARGUMENTS,

src/librustc_lint/lib.rs

@@ -336,11 +336,6 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
             reference: "issue #37872 <https://github.com/rust-lang/rust/issues/37872>",
             edition: None,
         },
-        FutureIncompatibleInfo {
-            id: LintId::of(LEGACY_CONSTRUCTOR_VISIBILITY),
-            reference: "issue #39207 <https://github.com/rust-lang/rust/issues/39207>",
-            edition: None,
-        },
         FutureIncompatibleInfo {
             id: LintId::of(MISSING_FRAGMENT_SPECIFIER),
             reference: "issue #40107 <https://github.com/rust-lang/rust/issues/40107>",
@@ -488,6 +483,8 @@ pub fn register_builtins(store: &mut lint::LintStore, sess: Option<&Session>) {
         "converted into hard error, see https://github.com/rust-lang/rust/issues/57742");
     store.register_removed("incoherent_fundamental_impls",
         "converted into hard error, see https://github.com/rust-lang/rust/issues/46205");
+    store.register_removed("legacy_constructor_visibility",
+        "converted into hard error, see https://github.com/rust-lang/rust/issues/39207");
 }
 
 pub fn register_internals(store: &mut lint::LintStore, sess: Option<&Session>) {

src/librustc_resolve/lib.rs

@@ -3495,24 +3495,7 @@ impl<'a> Resolver<'a> {
                 if is_expected(partial_res.base_res()) || partial_res.base_res() == Res::Err {
                     partial_res
                 } else {
-                    // Add a temporary hack to smooth the transition to new struct ctor
-                    // visibility rules. See #38932 for more details.
-                    let mut res = None;
-                    if let Res::Def(DefKind::Struct, def_id) = partial_res.base_res() {
-                        if let Some((ctor_res, ctor_vis))
-                                = self.struct_constructors.get(&def_id).cloned() {
-                            if is_expected(ctor_res) && self.is_accessible(ctor_vis) {
-                                let lint = lint::builtin::LEGACY_CONSTRUCTOR_VISIBILITY;
-                                self.session.buffer_lint(lint, id, span,
-                                    "private struct constructors are not usable through \
-                                     re-exports in outer modules",
-                                );
-                                res = Some(PartialRes::new(ctor_res));
-                            }
-                        }
-                    }
-
-                    res.unwrap_or_else(|| report_errors(self, Some(partial_res.base_res())))
+                    report_errors(self, Some(partial_res.base_res()))
                 }
             }
             Some(partial_res) if source.defer_to_typeck() => {

src/test/ui/privacy/legacy-ctor-visibility.rs

@@ -1,7 +1,3 @@
-// ignore-tidy-linelength
-
-#![allow(unused)]
-
 use m::S;
 
 mod m {
@@ -11,8 +7,7 @@ mod m {
         use S;
         fn f() {
             S(10);
-            //~^ ERROR private struct constructors are not usable through re-exports in outer modules
-            //~| WARN this was previously accepted
+            //~^ ERROR expected function, found struct `S`
         }
     }
 }

src/test/ui/privacy/legacy-ctor-visibility.stderr

@@ -1,12 +1,9 @@
-error: private struct constructors are not usable through re-exports in outer modules
-  --> $DIR/legacy-ctor-visibility.rs:13:13
+error[E0423]: expected function, found struct `S`
+  --> $DIR/legacy-ctor-visibility.rs:9:13
    |
 LL |             S(10);
-   |             ^
-   |
-   = note: `#[deny(legacy_constructor_visibility)]` on by default
-   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
-   = note: for more information, see issue #39207 <https://github.com/rust-lang/rust/issues/39207>
+   |             ^ help: a function with a similar name exists: `f`
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0423`.