Don't pass lint back out of lint decorator

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -578,7 +578,9 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs {
                     hir_id,
                     no_sanitize_span,
                     "`no_sanitize` will have no effect after inlining",
-                    |lint| lint.span_note(inline_span, "inlining requested here"),
+                    |lint| {
+                        lint.span_note(inline_span, "inlining requested here");
+                    },
                 )
             }
         }

compiler/rustc_hir_analysis/src/astconv/generics.rs

@@ -661,7 +661,7 @@ pub(crate) fn prohibit_explicit_late_bound_lifetimes(
                 args.args[0].hir_id(),
                 multispan,
                 msg,
-                |lint| lint,
+                |_| {},
             );
         }
 

compiler/rustc_hir_analysis/src/astconv/lint.rs

@@ -122,7 +122,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                             Applicability::MachineApplicable,
                         );
                         self.maybe_lint_blanket_trait_impl(self_ty, lint);
-                        lint
                     },
                 );
             }

compiler/rustc_hir_analysis/src/astconv/mod.rs

@@ -1506,8 +1506,6 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
                         format!("<{} as {}>::{}", qself_ty, tcx.item_name(trait_did), assoc_ident),
                         Applicability::MachineApplicable,
                     );
-
-                    lint
                 },
             );
         }

compiler/rustc_hir_analysis/src/check/check.rs

@@ -51,7 +51,7 @@ pub fn check_abi(tcx: TyCtxt<'_>, hir_id: hir::HirId, span: Span, abi: Abi) {
                 hir_id,
                 span,
                 "use of calling convention not supported on this target",
-                |lint| lint,
+                |_| {},
             );
         }
     }
@@ -190,7 +190,7 @@ fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
             "static of uninhabited type",
             |lint| {
                 lint
-                .note("uninhabited statics cannot be initialized, and any access would be an immediate error")
+                .note("uninhabited statics cannot be initialized, and any access would be an immediate error");
             },
         );
     }
@@ -1093,7 +1093,7 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>)
                             "this {descr} contains `{field_ty}`, which {note}, \
                                 and makes it not a breaking change to become \
                                 non-zero-sized in the future."
-                        ))
+                        ));
                     },
                 )
             } else {

compiler/rustc_hir_analysis/src/check/compare_impl_item.rs

@@ -574,7 +574,6 @@ fn emit_implied_wf_lint<'tcx>(
                     Applicability::MaybeIncorrect,
                 );
             }
-            lint
         },
     );
 }

compiler/rustc_hir_analysis/src/check/intrinsicck.rs

@@ -269,7 +269,6 @@ impl<'a, 'tcx> InlineAsmCtxt<'a, 'tcx> {
                         lint.help(format!(
                             "or use `{{{idx}:{default_modifier}}}` to keep the default formatting of `{default_result}`",
                         ));
-                        lint
                     },
                 );
             }

compiler/rustc_hir_analysis/src/check_unused.rs

@@ -45,7 +45,7 @@ fn check_unused_traits(tcx: TyCtxt<'_>, (): ()) {
             item.hir_id(),
             path.span,
             msg,
-            |lint| lint,
+            |_| {},
         );
     }
 }

compiler/rustc_hir_analysis/src/coherence/orphan.rs

@@ -522,7 +522,7 @@ fn lint_auto_trait_impl<'tcx>(
                 format!(
                     "try using the same sequence of generic parameters as the {self_descr} definition",
                 ),
-            )
+            );
         },
     );
 }

compiler/rustc_hir_analysis/src/collect/generics_of.rs

@@ -279,7 +279,7 @@ pub(super) fn generics_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Generics {
                             param.hir_id,
                             param.span,
                             TYPE_DEFAULT_NOT_ALLOWED,
-                            |lint| lint,
+                            |_| {},
                         );
                     }
                     Defaults::Deny => {

compiler/rustc_hir_analysis/src/collect/resolve_bound_vars.rs

@@ -925,7 +925,7 @@ impl<'a, 'tcx> Visitor<'tcx> for BoundVarContext<'a, 'tcx> {
                                     "you can use the `'static` lifetime directly, in place of `{}`",
                                     lifetime.ident,
                                 );
-                                lint.help(help)
+                                lint.help(help);
                             },
                         );
                     }

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -72,7 +72,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             orig_span,
                             custom_note
                                 .unwrap_or("any code following this expression is unreachable"),
-                        )
+                        );
                     },
                 )
             }

compiler/rustc_hir_typeck/src/method/prelude2021.rs

@@ -122,8 +122,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             format!("disambiguate the method call with `({self_adjusted})`",),
                         );
                     }
-
-                    lint
                 },
             );
         } else {
@@ -187,8 +185,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             ),
                         );
                     }
-
-                    lint
                 },
             );
         }
@@ -307,8 +303,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     format!("<{} as {}>::{}", self_ty_name, trait_name, method_name.name,),
                     Applicability::MachineApplicable,
                 );
-
-                lint
             },
         );
     }

compiler/rustc_hir_typeck/src/method/probe.rs

@@ -445,7 +445,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         scope_expr_id,
                         span,
                         "type annotations needed",
-                        |lint| lint,
+                        |_| {},
                     );
                 }
             } else {
@@ -1427,8 +1427,6 @@ impl<'tcx> Pick<'tcx> {
                         ));
                     }
                 }
-
-                lint
             },
         );
     }

compiler/rustc_hir_typeck/src/pat.rs

@@ -1845,8 +1845,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         lint.note(format!(
             "the pattern is of type `{ty}` and the `non_exhaustive_omitted_patterns` attribute was found",
         ));
-
-        lint
     });
     }
 

compiler/rustc_hir_typeck/src/upvar.rs

@@ -912,8 +912,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             Applicability::HasPlaceholders
                         );
                     }
-
-                    lint
                 },
             );
         }

compiler/rustc_lint/src/builtin.rs

@@ -2800,7 +2800,7 @@ impl<'tcx> LateLintPass<'tcx> for NamedAsmLabels {
                             NAMED_ASM_LABELS,
                             Some(target_spans),
                             fluent::lint_builtin_asm_labels,
-                            |lint| lint,
+                            |_| {},
                             BuiltinLintDiagnostics::NamedAsmLabel(
                                 "only local labels of the form `<number>:` should be used in inline asm"
                                     .to_string(),

compiler/rustc_lint/src/context.rs

@@ -520,19 +520,14 @@ pub trait LintContext {
     /// Emit a lint at the appropriate level, with an optional associated span and an existing
     /// diagnostic.
     ///
-    /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed
-    /// explanation.
-    ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
     #[rustc_lint_diagnostics]
     fn lookup_with_diagnostics(
         &self,
         lint: &'static Lint,
         span: Option<impl Into<MultiSpan>>,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
         diagnostic: BuiltinLintDiagnostics,
     ) {
         // We first generate a blank diagnostic.
@@ -986,18 +981,14 @@ pub trait LintContext {
     // set the span in their `decorate` function (preferably using set_span).
     /// Emit a lint at the appropriate level, with an optional associated span.
     ///
-    /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
-    ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
     #[rustc_lint_diagnostics]
     fn lookup<S: Into<MultiSpan>>(
         &self,
         lint: &'static Lint,
         span: Option<S>,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     );
 
     /// Emit a lint at `span` from a lint struct (some type that implements `DecorateLint`,
@@ -1008,23 +999,21 @@ pub trait LintContext {
         span: S,
         decorator: impl for<'a> DecorateLint<'a, ()>,
     ) {
-        self.lookup(lint, Some(span), decorator.msg(), |diag| decorator.decorate_lint(diag));
+        self.lookup(lint, Some(span), decorator.msg(), |diag| {
+            decorator.decorate_lint(diag);
+        });
     }
 
     /// Emit a lint at the appropriate level, with an associated span.
     ///
-    /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
-    ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
     #[rustc_lint_diagnostics]
     fn struct_span_lint<S: Into<MultiSpan>>(
         &self,
         lint: &'static Lint,
         span: S,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     ) {
         self.lookup(lint, Some(span), msg, decorate);
     }
@@ -1033,23 +1022,19 @@ pub trait LintContext {
     /// generated by `#[derive(LintDiagnostic)]`).
     fn emit_lint(&self, lint: &'static Lint, decorator: impl for<'a> DecorateLint<'a, ()>) {
         self.lookup(lint, None as Option<Span>, decorator.msg(), |diag| {
-            decorator.decorate_lint(diag)
+            decorator.decorate_lint(diag);
         });
     }
 
     /// Emit a lint at the appropriate level, with no associated span.
     ///
-    /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
-    ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
     #[rustc_lint_diagnostics]
     fn lint(
         &self,
         lint: &'static Lint,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     ) {
         self.lookup(lint, None as Option<Span>, msg, decorate);
     }
@@ -1113,9 +1098,7 @@ impl<'tcx> LintContext for LateContext<'tcx> {
         lint: &'static Lint,
         span: Option<S>,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     ) {
         let hir_id = self.last_node_with_lint_attrs;
 
@@ -1142,9 +1125,7 @@ impl LintContext for EarlyContext<'_> {
         lint: &'static Lint,
         span: Option<S>,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     ) {
         self.builder.struct_lint(lint, span.map(|s| s.into()), msg, decorate)
     }

compiler/rustc_lint/src/early.rs

@@ -45,13 +45,7 @@ impl<'a, T: EarlyLintPass> EarlyContextAndPass<'a, T> {
     fn inlined_check_id(&mut self, id: ast::NodeId) {
         for early_lint in self.context.buffered.take(id) {
             let BufferedEarlyLint { span, msg, node_id: _, lint_id, diagnostic } = early_lint;
-            self.context.lookup_with_diagnostics(
-                lint_id.lint,
-                Some(span),
-                msg,
-                |lint| lint,
-                diagnostic,
-            );
+            self.context.lookup_with_diagnostics(lint_id.lint, Some(span), msg, |_| {}, diagnostic);
         }
     }
 

compiler/rustc_lint/src/levels.rs

@@ -1077,7 +1077,6 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                             GateIssue::Language,
                             lint_from_cli,
                         );
-                        lint
                     },
                 );
                 return false;
@@ -1094,8 +1093,6 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     /// Used to emit a lint-related diagnostic based on the current state of
     /// this lint context.
     ///
-    /// Return value of the `decorate` closure is ignored, see [`struct_lint_level`] for a detailed explanation.
-    ///
     /// [`struct_lint_level`]: rustc_middle::lint::struct_lint_level#decorate-signature
     #[rustc_lint_diagnostics]
     #[track_caller]
@@ -1104,9 +1101,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
         lint: &'static Lint,
         span: Option<MultiSpan>,
         msg: impl Into<DiagnosticMessage>,
-        decorate: impl for<'a, 'b> FnOnce(
-            &'b mut DiagnosticBuilder<'a, ()>,
-        ) -> &'b mut DiagnosticBuilder<'a, ()>,
+        decorate: impl for<'a, 'b> FnOnce(&'b mut DiagnosticBuilder<'a, ()>),
     ) {
         let (level, src) = self.lint_level(lint);
         struct_lint_level(self.sess, lint, level, src, span, msg, decorate)
@@ -1121,15 +1116,15 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     ) {
         let (level, src) = self.lint_level(lint);
         struct_lint_level(self.sess, lint, level, src, Some(span), decorate.msg(), |lint| {
-            decorate.decorate_lint(lint)
+            decorate.decorate_lint(lint);
         });
     }
 
     #[track_caller]
     pub fn emit_lint(&self, lint: &'static Lint, decorate: impl for<'a> DecorateLint<'a, ()>) {
         let (level, src) = self.lint_level(lint);
         struct_lint_level(self.sess, lint, level, src, None, decorate.msg(), |lint| {
-            decorate.decorate_lint(lint)
+            decorate.decorate_lint(lint);
         });
     }
 }

compiler/rustc_lint/src/non_fmt_panic.rs

@@ -126,7 +126,7 @@ fn check_panic<'tcx>(cx: &LateContext<'tcx>, f: &'tcx hir::Expr<'tcx>, arg: &'tc
         lint.note(fluent::lint_more_info_note);
         if !is_arg_inside_call(arg_span, span) {
             // No clue where this argument is coming from.
-            return lint;
+            return;
         }
         if arg_macro.is_some_and(|id| cx.tcx.is_diagnostic_item(sym::format_macro, id)) {
             // A case of `panic!(format!(..))`.
@@ -207,7 +207,6 @@ fn check_panic<'tcx>(cx: &LateContext<'tcx>, f: &'tcx hir::Expr<'tcx>, arg: &'tc
                 }
             }
         }
-        lint
     });
 }