resolve: Partially convert ambiguous_glob_imports lint into a hard error

compiler/rustc_codegen_gcc/build_system/src/test.rs

@@ -826,8 +826,6 @@ fn valid_ui_error_pattern_test(file: &str) -> bool {
         "type-alias-impl-trait/auxiliary/cross_crate_ice.rs",
         "type-alias-impl-trait/auxiliary/cross_crate_ice2.rs",
         "macros/rfc-2011-nicer-assert-messages/auxiliary/common.rs",
-        "imports/ambiguous-1.rs",
-        "imports/ambiguous-4-extern.rs",
         "entry-point/auxiliary/bad_main_functions.rs",
     ]
     .iter()

compiler/rustc_lint_defs/src/builtin.rs

@@ -4577,7 +4577,7 @@ declare_lint! {
     ///
     /// ### Example
     ///
-    /// ```rust,compile_fail
+    /// ```rust,ignore (needs extern crate)
     /// #![deny(ambiguous_glob_imports)]
     /// pub fn foo() -> u32 {
     ///     use sub::*;
@@ -4593,8 +4593,6 @@ declare_lint! {
     /// }
     /// ```
     ///
-    /// {{produces}}
-    ///
     /// ### Explanation
     ///
     /// Previous versions of Rust compile it successfully because it

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -54,7 +54,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         decl: Decl<'ra>,
     ) {
         if let Err(old_decl) =
-            self.try_plant_decl_into_local_module(ident, orig_ident_span, ns, decl, false)
+            self.try_plant_decl_into_local_module(ident, orig_ident_span, ns, decl)
         {
             self.report_conflict(ident, ns, old_decl, decl);
         }
@@ -88,13 +88,11 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         vis: Visibility<DefId>,
         span: Span,
         expansion: LocalExpnId,
-        ambiguity: Option<Decl<'ra>>,
+        ambiguity: Option<(Decl<'ra>, bool)>,
     ) {
         let decl = self.arenas.alloc_decl(DeclData {
             kind: DeclKind::Def(res),
             ambiguity: CmCell::new(ambiguity),
-            // External ambiguities always report the `AMBIGUOUS_GLOB_IMPORTS` lint at the moment.
-            warn_ambiguity: CmCell::new(true),
             vis: CmCell::new(vis),
             span,
             expansion,
@@ -292,7 +290,8 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
             let ModChild { ident: _, res, vis, ref reexport_chain } = *ambig_child;
             let span = child_span(self, reexport_chain, res);
             let res = res.expect_non_local();
-            self.arenas.new_def_decl(res, vis, span, expansion, Some(parent))
+            // External ambiguities always report the `AMBIGUOUS_GLOB_IMPORTS` lint at the moment.
+            (self.arenas.new_def_decl(res, vis, span, expansion, Some(parent)), true)
         });
 
         // Record primary definitions.

compiler/rustc_resolve/src/diagnostics.rs

@@ -1133,7 +1133,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         .emit()
     }
 
-    fn def_path_str(&self, mut def_id: DefId) -> String {
+    pub(crate) fn def_path_str(&self, mut def_id: DefId) -> String {
         // We can't use `def_path_str` in resolve.
         let mut path = vec![def_id];
         while let Some(parent) = self.tcx.opt_parent(def_id) {

compiler/rustc_resolve/src/lib.rs

@@ -844,10 +844,7 @@ impl<'ra> fmt::Debug for Module<'ra> {
 #[derive(Clone, Debug)]
 struct DeclData<'ra> {
     kind: DeclKind<'ra>,
-    ambiguity: CmCell<Option<Decl<'ra>>>,
-    /// Produce a warning instead of an error when reporting ambiguities inside this binding.
-    /// May apply to indirect ambiguities under imports, so `ambiguity.is_some()` is not required.
-    warn_ambiguity: CmCell<bool>,
+    ambiguity: CmCell<Option<(Decl<'ra>, bool /*warning*/)>>,
     expansion: LocalExpnId,
     span: Span,
     vis: CmCell<Visibility<DefId>>,
@@ -989,7 +986,7 @@ impl<'ra> DeclData<'ra> {
 
     fn descent_to_ambiguity(self: Decl<'ra>) -> Option<(Decl<'ra>, Decl<'ra>)> {
         match self.ambiguity.get() {
-            Some(ambig_binding) => Some((self, ambig_binding)),
+            Some((ambig_binding, _)) => Some((self, ambig_binding)),
             None => match self.kind {
                 DeclKind::Import { source_decl, .. } => source_decl.descent_to_ambiguity(),
                 _ => None,
@@ -1005,14 +1002,6 @@ impl<'ra> DeclData<'ra> {
             }
     }
 
-    fn warn_ambiguity_recursive(&self) -> bool {
-        self.warn_ambiguity.get()
-            || match self.kind {
-                DeclKind::Import { source_decl, .. } => source_decl.warn_ambiguity_recursive(),
-                _ => false,
-            }
-    }
-
     fn is_possibly_imported_variant(&self) -> bool {
         match self.kind {
             DeclKind::Import { source_decl, .. } => source_decl.is_possibly_imported_variant(),
@@ -1405,7 +1394,6 @@ impl<'ra> ResolverArenas<'ra> {
         self.alloc_decl(DeclData {
             kind: DeclKind::Def(res),
             ambiguity: CmCell::new(None),
-            warn_ambiguity: CmCell::new(false),
             vis: CmCell::new(vis),
             span,
             expansion,
@@ -2093,17 +2081,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
     }
 
     fn record_use(&mut self, ident: Ident, used_decl: Decl<'ra>, used: Used) {
-        self.record_use_inner(ident, used_decl, used, used_decl.warn_ambiguity.get());
-    }
-
-    fn record_use_inner(
-        &mut self,
-        ident: Ident,
-        used_decl: Decl<'ra>,
-        used: Used,
-        warn_ambiguity: bool,
-    ) {
-        if let Some(b2) = used_decl.ambiguity.get() {
+        if let Some((b2, warning)) = used_decl.ambiguity.get() {
             let ambiguity_error = AmbiguityError {
                 kind: AmbiguityKind::GlobVsGlob,
                 ambig_vis: None,
@@ -2112,7 +2090,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 b2,
                 scope1: Scope::ModuleGlobs(used_decl.parent_module.unwrap(), None),
                 scope2: Scope::ModuleGlobs(b2.parent_module.unwrap(), None),
-                warning: if warn_ambiguity { Some(AmbiguityWarning::GlobImport) } else { None },
+                warning: if warning { Some(AmbiguityWarning::GlobImport) } else { None },
             };
             if !self.matches_previous_ambiguity_error(&ambiguity_error) {
                 // avoid duplicated span information to be emit out
@@ -2162,12 +2140,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
                 self.used_imports.insert(id);
             }
             self.add_to_glob_map(import, ident.name);
-            self.record_use_inner(
-                ident,
-                source_decl,
-                Used::Other,
-                warn_ambiguity || source_decl.warn_ambiguity.get(),
-            );
+            self.record_use(ident, source_decl, Used::Other);
         }
     }
 

tests/ui/imports/ambiguous-1.rs

@@ -1,8 +1,5 @@
-//@ check-pass
 // https://github.com/rust-lang/rust/pull/112743#issuecomment-1601986883
 
-#![warn(ambiguous_glob_imports)]
-
 macro_rules! m {
     () => {
       pub fn id() {}
@@ -27,6 +24,5 @@ pub use openssl::*;
 
 fn main() {
     id();
-    //~^ WARNING `id` is ambiguous
-    //~| WARNING this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+    //~^ ERROR `id` is ambiguous
 }

tests/ui/imports/ambiguous-1.stderr

@@ -1,68 +1,34 @@
-warning: ambiguous glob re-exports
-  --> $DIR/ambiguous-1.rs:13:13
-   |
-LL |     pub use self::evp::*;
-   |             ^^^^^^^^^^^^ the name `id` in the value namespace is first re-exported here
-LL |
-LL |     pub use self::handwritten::*;
-   |             -------------------- but the name `id` in the value namespace is also re-exported here
-   |
-   = note: `#[warn(ambiguous_glob_reexports)]` on by default
-
-warning: `id` is ambiguous
-  --> $DIR/ambiguous-1.rs:29:5
+error[E0659]: `id` is ambiguous
+  --> $DIR/ambiguous-1.rs:26:5
    |
 LL |     id();
    |     ^^ ambiguous name
    |
    = note: ambiguous because of multiple glob imports of a name in the same module
 note: `id` could refer to the function imported here
-  --> $DIR/ambiguous-1.rs:13:13
+  --> $DIR/ambiguous-1.rs:10:13
    |
 LL |     pub use self::evp::*;
    |             ^^^^^^^^^^^^
    = help: consider adding an explicit import of `id` to disambiguate
 note: `id` could also refer to the function imported here
-  --> $DIR/ambiguous-1.rs:15:13
+  --> $DIR/ambiguous-1.rs:12:13
    |
 LL |     pub use self::handwritten::*;
    |             ^^^^^^^^^^^^^^^^^^^^
    = help: consider adding an explicit import of `id` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-note: the lint level is defined here
-  --> $DIR/ambiguous-1.rs:4:9
-   |
-LL | #![warn(ambiguous_glob_imports)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^
-
-warning: 2 warnings emitted
 
-Future incompatibility report: Future breakage diagnostic:
-warning: `id` is ambiguous
-  --> $DIR/ambiguous-1.rs:29:5
-   |
-LL |     id();
-   |     ^^ ambiguous name
-   |
-   = note: ambiguous because of multiple glob imports of a name in the same module
-note: `id` could refer to the function imported here
-  --> $DIR/ambiguous-1.rs:13:13
+warning: ambiguous glob re-exports
+  --> $DIR/ambiguous-1.rs:10:13
    |
 LL |     pub use self::evp::*;
-   |             ^^^^^^^^^^^^
-   = help: consider adding an explicit import of `id` to disambiguate
-note: `id` could also refer to the function imported here
-  --> $DIR/ambiguous-1.rs:15:13
-   |
+   |             ^^^^^^^^^^^^ the name `id` in the value namespace is first re-exported here
+LL |
 LL |     pub use self::handwritten::*;
-   |             ^^^^^^^^^^^^^^^^^^^^
-   = help: consider adding an explicit import of `id` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-note: the lint level is defined here
-  --> $DIR/ambiguous-1.rs:4:9
+   |             -------------------- but the name `id` in the value namespace is also re-exported here
    |
-LL | #![warn(ambiguous_glob_imports)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^
+   = note: `#[warn(ambiguous_glob_reexports)]` on by default
+
+error: aborting due to 1 previous error; 1 warning emitted
 
+For more information about this error, try `rustc --explain E0659`.

tests/ui/imports/ambiguous-10.rs

@@ -14,5 +14,4 @@ use crate::a::*;
 use crate::b::*;
 fn c(_: Token) {}
 //~^ ERROR `Token` is ambiguous
-//~| WARNING this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 fn main() { }

tests/ui/imports/ambiguous-10.stderr

@@ -1,4 +1,4 @@
-error: `Token` is ambiguous
+error[E0659]: `Token` is ambiguous
   --> $DIR/ambiguous-10.rs:15:9
    |
 LL | fn c(_: Token) {}
@@ -17,33 +17,7 @@ note: `Token` could also refer to the enum imported here
 LL | use crate::b::*;
    |     ^^^^^^^^^^^
    = help: consider adding an explicit import of `Token` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
 
 error: aborting due to 1 previous error
 
-Future incompatibility report: Future breakage diagnostic:
-error: `Token` is ambiguous
-  --> $DIR/ambiguous-10.rs:15:9
-   |
-LL | fn c(_: Token) {}
-   |         ^^^^^ ambiguous name
-   |
-   = note: ambiguous because of multiple glob imports of a name in the same module
-note: `Token` could refer to the enum imported here
-  --> $DIR/ambiguous-10.rs:13:5
-   |
-LL | use crate::a::*;
-   |     ^^^^^^^^^^^
-   = help: consider adding an explicit import of `Token` to disambiguate
-note: `Token` could also refer to the enum imported here
-  --> $DIR/ambiguous-10.rs:14:5
-   |
-LL | use crate::b::*;
-   |     ^^^^^^^^^^^
-   = help: consider adding an explicit import of `Token` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
-
+For more information about this error, try `rustc --explain E0659`.

tests/ui/imports/ambiguous-12.rs

@@ -20,5 +20,4 @@ use crate::public::*;
 fn main() {
     b();
     //~^ ERROR `b` is ambiguous
-    //~| WARNING this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 }

tests/ui/imports/ambiguous-12.stderr

@@ -1,4 +1,4 @@
-error: `b` is ambiguous
+error[E0659]: `b` is ambiguous
   --> $DIR/ambiguous-12.rs:21:5
    |
 LL |     b();
@@ -17,33 +17,7 @@ note: `b` could also refer to the function imported here
 LL | use crate::public::*;
    |     ^^^^^^^^^^^^^^^^
    = help: consider adding an explicit import of `b` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
 
 error: aborting due to 1 previous error
 
-Future incompatibility report: Future breakage diagnostic:
-error: `b` is ambiguous
-  --> $DIR/ambiguous-12.rs:21:5
-   |
-LL |     b();
-   |     ^ ambiguous name
-   |
-   = note: ambiguous because of multiple glob imports of a name in the same module
-note: `b` could refer to the function imported here
-  --> $DIR/ambiguous-12.rs:17:5
-   |
-LL | use crate::ciphertext::*;
-   |     ^^^^^^^^^^^^^^^^^^^^
-   = help: consider adding an explicit import of `b` to disambiguate
-note: `b` could also refer to the function imported here
-  --> $DIR/ambiguous-12.rs:18:5
-   |
-LL | use crate::public::*;
-   |     ^^^^^^^^^^^^^^^^
-   = help: consider adding an explicit import of `b` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
-
+For more information about this error, try `rustc --explain E0659`.

tests/ui/imports/ambiguous-13.rs

@@ -17,5 +17,4 @@ use crate::content::*;
 
 fn a(_: Rect) {}
 //~^ ERROR `Rect` is ambiguous
-//~| WARNING this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 fn main() { }

tests/ui/imports/ambiguous-13.stderr

@@ -1,4 +1,4 @@
-error: `Rect` is ambiguous
+error[E0659]: `Rect` is ambiguous
   --> $DIR/ambiguous-13.rs:18:9
    |
 LL | fn a(_: Rect) {}
@@ -17,33 +17,7 @@ note: `Rect` could also refer to the struct imported here
 LL | use crate::content::*;
    |     ^^^^^^^^^^^^^^^^^
    = help: consider adding an explicit import of `Rect` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
 
 error: aborting due to 1 previous error
 
-Future incompatibility report: Future breakage diagnostic:
-error: `Rect` is ambiguous
-  --> $DIR/ambiguous-13.rs:18:9
-   |
-LL | fn a(_: Rect) {}
-   |         ^^^^ ambiguous name
-   |
-   = note: ambiguous because of multiple glob imports of a name in the same module
-note: `Rect` could refer to the struct imported here
-  --> $DIR/ambiguous-13.rs:15:5
-   |
-LL | use crate::object::*;
-   |     ^^^^^^^^^^^^^^^^
-   = help: consider adding an explicit import of `Rect` to disambiguate
-note: `Rect` could also refer to the struct imported here
-  --> $DIR/ambiguous-13.rs:16:5
-   |
-LL | use crate::content::*;
-   |     ^^^^^^^^^^^^^^^^^
-   = help: consider adding an explicit import of `Rect` to disambiguate
-   = 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 #114095 <https://github.com/rust-lang/rust/issues/114095>
-   = note: `#[deny(ambiguous_glob_imports)]` (part of `#[deny(future_incompatible)]`) on by default
-
+For more information about this error, try `rustc --explain E0659`.