Rollup merge of #119388 - Enselic:prevent-lint-triplication, r=cjgillot

rustc_lint: Prevent triplication of various lints

Prevent triplication of various lints. The triplication happens because we run the same lint three times (or less in some cases):
* In `BuiltinCombinedPreExpansionLintPass`
* In `BuiltinCombinedEarlyLintPass`
* In `shallow_lint_levels_on()`

Only run the lints one time by checking the `lint_added_lints` bool.

Set your GitHub diff setting to ignore whitespaces changes when reviewing this PR, since I had to enclose a block inside an if.

Closes #73301

(I found this while exploring the code related to [this](https://github.com/rust-lang/rust/pull/119251#discussion_r1435677330) comment.)

37 files changed, 64 insertions, 664 deletions

diff --git a/compiler/rustc_error_codes/src/error_codes/E0453.md b/compiler/rustc_error_codes/src/error_codes/E0453.md
index 11789db8f36..86ca0d9eca9 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0453.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0453.md
@@ -8,8 +8,8 @@ Example of erroneous code:
 
 #[allow(non_snake_case)]
 fn main() {
-    let MyNumber = 2; // error: allow(non_snake_case) overruled by outer
-                      //        forbid(non_snake_case)
+    // error: allow(non_snake_case) incompatible with previous forbid
+    let MyNumber = 2;
 }
 ```
 
diff --git a/compiler/rustc_lint/src/context.rs b/compiler/rustc_lint/src/context.rs
index 40b70ba4e04..39c965e75d6 100644
--- a/compiler/rustc_lint/src/context.rs
+++ b/compiler/rustc_lint/src/context.rs
@@ -1069,7 +1069,7 @@ impl<'a> EarlyContext<'a> {
     pub(crate) fn new(
         sess: &'a Session,
         features: &'a Features,
-        warn_about_weird_lints: bool,
+        lint_added_lints: bool,
         lint_store: &'a LintStore,
         registered_tools: &'a RegisteredTools,
         buffered: LintBuffer,
@@ -1078,7 +1078,7 @@ impl<'a> EarlyContext<'a> {
             builder: LintLevelsBuilder::new(
                 sess,
                 features,
-                warn_about_weird_lints,
+                lint_added_lints,
                 lint_store,
                 registered_tools,
             ),
diff --git a/compiler/rustc_lint/src/levels.rs b/compiler/rustc_lint/src/levels.rs
index 17c56f1ca58..c229728cb79 100644
--- a/compiler/rustc_lint/src/levels.rs
+++ b/compiler/rustc_lint/src/levels.rs
@@ -135,7 +135,7 @@ fn lint_expectations(tcx: TyCtxt<'_>, (): ()) -> Vec<(LintExpectationId, LintExp
             unstable_to_stable_ids: FxHashMap::default(),
             empty: FxHashMap::default(),
         },
-        warn_about_weird_lints: false,
+        lint_added_lints: false,
         store,
         registered_tools: tcx.registered_tools(()),
     };
@@ -164,7 +164,7 @@ fn shallow_lint_levels_on(tcx: TyCtxt<'_>, owner: hir::OwnerId) -> ShallowLintLe
             empty: FxHashMap::default(),
             attrs,
         },
-        warn_about_weird_lints: false,
+        lint_added_lints: false,
         store,
         registered_tools: tcx.registered_tools(()),
     };
@@ -451,7 +451,7 @@ pub struct LintLevelsBuilder<'s, P> {
     sess: &'s Session,
     features: &'s Features,
     provider: P,
-    warn_about_weird_lints: bool,
+    lint_added_lints: bool,
     store: &'s LintStore,
     registered_tools: &'s RegisteredTools,
 }
@@ -464,7 +464,7 @@ impl<'s> LintLevelsBuilder<'s, TopDown> {
     pub(crate) fn new(
         sess: &'s Session,
         features: &'s Features,
-        warn_about_weird_lints: bool,
+        lint_added_lints: bool,
         store: &'s LintStore,
         registered_tools: &'s RegisteredTools,
     ) -> Self {
@@ -472,7 +472,7 @@ impl<'s> LintLevelsBuilder<'s, TopDown> {
             sess,
             features,
             provider: TopDown { sets: LintLevelSets::new(), cur: COMMAND_LINE },
-            warn_about_weird_lints,
+            lint_added_lints,
             store,
             registered_tools,
         };
@@ -642,7 +642,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
         //
         // This means that this only errors if we're truly lowering the lint
         // level from forbid.
-        if level != Level::Forbid {
+        if self.lint_added_lints && level != Level::Forbid {
             if let Level::Forbid = old_level {
                 // Backwards compatibility check:
                 //
@@ -968,7 +968,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
                         continue;
                     }
 
-                    _ if !self.warn_about_weird_lints => {}
+                    _ if !self.lint_added_lints => {}
 
                     CheckLintNameResult::Renamed(ref replace) => {
                         let suggestion =
@@ -1029,7 +1029,7 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
             }
         }
 
-        if !is_crate_node {
+        if self.lint_added_lints && !is_crate_node {
             for (id, &(level, ref src)) in self.current_specs().iter() {
                 if !id.lint.crate_level_only {
                     continue;
@@ -1054,33 +1054,33 @@ impl<'s, P: LintLevelsProvider> LintLevelsBuilder<'s, P> {
     /// Checks if the lint is gated on a feature that is not enabled.
     ///
     /// Returns `true` if the lint's feature is enabled.
-    // FIXME only emit this once for each attribute, instead of repeating it 4 times for
-    // pre-expansion lints, post-expansion lints, `shallow_lint_levels_on` and `lint_expectations`.
     #[track_caller]
     fn check_gated_lint(&self, lint_id: LintId, span: Span, lint_from_cli: bool) -> bool {
         if let Some(feature) = lint_id.lint.feature_gate {
             if !self.features.active(feature) {
-                let lint = builtin::UNKNOWN_LINTS;
-                let (level, src) = self.lint_level(builtin::UNKNOWN_LINTS);
-                struct_lint_level(
-                    self.sess,
-                    lint,
-                    level,
-                    src,
-                    Some(span.into()),
-                    fluent::lint_unknown_gated_lint,
-                    |lint| {
-                        lint.set_arg("name", lint_id.lint.name_lower());
-                        lint.note(fluent::lint_note);
-                        rustc_session::parse::add_feature_diagnostics_for_issue(
-                            lint,
-                            &self.sess.parse_sess,
-                            feature,
-                            GateIssue::Language,
-                            lint_from_cli,
-                        );
-                    },
-                );
+                if self.lint_added_lints {
+                    let lint = builtin::UNKNOWN_LINTS;
+                    let (level, src) = self.lint_level(builtin::UNKNOWN_LINTS);
+                    struct_lint_level(
+                        self.sess,
+                        lint,
+                        level,
+                        src,
+                        Some(span.into()),
+                        fluent::lint_unknown_gated_lint,
+                        |lint| {
+                            lint.set_arg("name", lint_id.lint.name_lower());
+                            lint.note(fluent::lint_note);
+                            rustc_session::parse::add_feature_diagnostics_for_issue(
+                                lint,
+                                &self.sess.parse_sess,
+                                feature,
+                                GateIssue::Language,
+                                lint_from_cli,
+                            );
+                        },
+                    );
+                }
                 return false;
             }
         }
diff --git a/tests/ui/error-codes/E0453.rs b/tests/ui/error-codes/E0453.rs
index ca9573c5b46..8ed724dd3fc 100644
--- a/tests/ui/error-codes/E0453.rs
+++ b/tests/ui/error-codes/E0453.rs
@@ -2,6 +2,5 @@
 
 #[allow(non_snake_case)]
 //~^ ERROR allow(non_snake_case) incompatible
-//~| ERROR allow(non_snake_case) incompatible
 fn main() {
 }
diff --git a/tests/ui/error-codes/E0453.stderr b/tests/ui/error-codes/E0453.stderr
index bb2c39298c0..9a89f0d41e4 100644
--- a/tests/ui/error-codes/E0453.stderr
+++ b/tests/ui/error-codes/E0453.stderr
@@ -7,17 +7,6 @@ LL |
 LL | #[allow(non_snake_case)]
    |         ^^^^^^^^^^^^^^ overruled by previous forbid
 
-error[E0453]: allow(non_snake_case) incompatible with previous forbid
-  --> $DIR/E0453.rs:3:9
-   |
-LL | #![forbid(non_snake_case)]
-   |           -------------- `forbid` level set here
-LL |
-LL | #[allow(non_snake_case)]
-   |         ^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0453`.
diff --git a/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.rs b/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.rs
index 0467dea621b..4e296b96ca9 100644
--- a/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.rs
+++ b/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.rs
@@ -2,11 +2,7 @@
 
 #![deny(multiple_supertrait_upcastable)]
 //~^ WARNING unknown lint: `multiple_supertrait_upcastable`
-//~| WARNING unknown lint: `multiple_supertrait_upcastable`
-//~| WARNING unknown lint: `multiple_supertrait_upcastable`
 #![warn(multiple_supertrait_upcastable)]
 //~^ WARNING unknown lint: `multiple_supertrait_upcastable`
-//~| WARNING unknown lint: `multiple_supertrait_upcastable`
-//~| WARNING unknown lint: `multiple_supertrait_upcastable`
 
 fn main() {}
diff --git a/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.stderr b/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.stderr
index 5e14bf6397f..f6fcf4ee3ed 100644
--- a/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.stderr
+++ b/tests/ui/feature-gates/feature-gate-multiple_supertrait_upcastable.stderr
@@ -9,7 +9,7 @@ LL | #![deny(multiple_supertrait_upcastable)]
    = note: `#[warn(unknown_lints)]` on by default
 
 warning: unknown lint: `multiple_supertrait_upcastable`
-  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:7:1
+  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:5:1
    |
 LL | #![warn(multiple_supertrait_upcastable)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -17,45 +17,5 @@ LL | #![warn(multiple_supertrait_upcastable)]
    = note: the `multiple_supertrait_upcastable` lint is unstable
    = help: add `#![feature(multiple_supertrait_upcastable)]` to the crate attributes to enable
 
-warning: unknown lint: `multiple_supertrait_upcastable`
-  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:3:1
-   |
-LL | #![deny(multiple_supertrait_upcastable)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `multiple_supertrait_upcastable` lint is unstable
-   = help: add `#![feature(multiple_supertrait_upcastable)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `multiple_supertrait_upcastable`
-  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:7:1
-   |
-LL | #![warn(multiple_supertrait_upcastable)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `multiple_supertrait_upcastable` lint is unstable
-   = help: add `#![feature(multiple_supertrait_upcastable)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `multiple_supertrait_upcastable`
-  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:3:1
-   |
-LL | #![deny(multiple_supertrait_upcastable)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `multiple_supertrait_upcastable` lint is unstable
-   = help: add `#![feature(multiple_supertrait_upcastable)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `multiple_supertrait_upcastable`
-  --> $DIR/feature-gate-multiple_supertrait_upcastable.rs:7:1
-   |
-LL | #![warn(multiple_supertrait_upcastable)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `multiple_supertrait_upcastable` lint is unstable
-   = help: add `#![feature(multiple_supertrait_upcastable)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 6 warnings emitted
+warning: 2 warnings emitted
 
diff --git a/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs b/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs
index 1922bfb4913..1db3c2ccdde 100644
--- a/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs
+++ b/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.rs
@@ -2,12 +2,8 @@
 
 #![deny(non_exhaustive_omitted_patterns)]
 //~^ WARNING unknown lint: `non_exhaustive_omitted_patterns`
-//~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-//~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
 #![allow(non_exhaustive_omitted_patterns)]
 //~^ WARNING unknown lint: `non_exhaustive_omitted_patterns`
-//~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-//~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
 
 fn main() {
     enum Foo {
@@ -19,9 +15,6 @@ fn main() {
     #[allow(non_exhaustive_omitted_patterns)]
     //~^ WARNING unknown lint: `non_exhaustive_omitted_patterns`
     //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
     match Foo::A {
         //~^ ERROR non-exhaustive patterns: `Foo::C` not covered
         Foo::A => {}
@@ -31,9 +24,6 @@ fn main() {
     #[warn(non_exhaustive_omitted_patterns)]
     //~^ WARNING unknown lint: `non_exhaustive_omitted_patterns`
     //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
-    //~| WARNING unknown lint: `non_exhaustive_omitted_patterns`
     match Foo::A {
         Foo::A => {}
         Foo::B => {}
diff --git a/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr b/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr
index a5333713977..955d7fe3f3e 100644
--- a/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr
+++ b/tests/ui/feature-gates/feature-gate-non_exhaustive_omitted_patterns_lint.stderr
@@ -10,7 +10,7 @@ LL | #![deny(non_exhaustive_omitted_patterns)]
    = note: `#[warn(unknown_lints)]` on by default
 
 warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:7:1
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:5:1
    |
 LL | #![allow(non_exhaustive_omitted_patterns)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -20,7 +20,7 @@ LL | #![allow(non_exhaustive_omitted_patterns)]
    = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
 
 warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:19:5
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:15:5
    |
 LL |     #[allow(non_exhaustive_omitted_patterns)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -30,7 +30,7 @@ LL |     #[allow(non_exhaustive_omitted_patterns)]
    = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
 
 warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:19:5
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:15:5
    |
 LL |     #[allow(non_exhaustive_omitted_patterns)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -41,7 +41,7 @@ LL |     #[allow(non_exhaustive_omitted_patterns)]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:31:5
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:24:5
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -51,73 +51,7 @@ LL |     #[warn(non_exhaustive_omitted_patterns)]
    = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
 
 warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:31:5
-   |
-LL |     #[warn(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:3:1
-   |
-LL | #![deny(non_exhaustive_omitted_patterns)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:7:1
-   |
-LL | #![allow(non_exhaustive_omitted_patterns)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:19:5
-   |
-LL |     #[allow(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:19:5
-   |
-LL |     #[allow(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:31:5
-   |
-LL |     #[warn(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:31:5
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:24:5
    |
 LL |     #[warn(non_exhaustive_omitted_patterns)]
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -128,13 +62,13 @@ LL |     #[warn(non_exhaustive_omitted_patterns)]
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
 error[E0004]: non-exhaustive patterns: `Foo::C` not covered
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:25:11
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:18:11
    |
 LL |     match Foo::A {
    |           ^^^^^^ pattern `Foo::C` not covered
    |
 note: `Foo` defined here
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:13:10
+  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:9:10
    |
 LL |     enum Foo {
    |          ^^^
@@ -148,50 +82,6 @@ LL ~         Foo::B => {},
 LL +         Foo::C => todo!()
    |
 
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:3:1
-   |
-LL | #![deny(non_exhaustive_omitted_patterns)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:7:1
-   |
-LL | #![allow(non_exhaustive_omitted_patterns)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:19:5
-   |
-LL |     #[allow(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `non_exhaustive_omitted_patterns`
-  --> $DIR/feature-gate-non_exhaustive_omitted_patterns_lint.rs:31:5
-   |
-LL |     #[warn(non_exhaustive_omitted_patterns)]
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `non_exhaustive_omitted_patterns` lint is unstable
-   = note: see issue #89554 <https://github.com/rust-lang/rust/issues/89554> for more information
-   = help: add `#![feature(non_exhaustive_omitted_patterns_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 1 previous error; 16 warnings emitted
+error: aborting due to 1 previous error; 6 warnings emitted
 
 For more information about this error, try `rustc --explain E0004`.
diff --git a/tests/ui/feature-gates/feature-gate-strict_provenance.rs b/tests/ui/feature-gates/feature-gate-strict_provenance.rs
index 75d0ee5700d..24b8369b3d8 100644
--- a/tests/ui/feature-gates/feature-gate-strict_provenance.rs
+++ b/tests/ui/feature-gates/feature-gate-strict_provenance.rs
@@ -2,12 +2,8 @@
 
 #![deny(fuzzy_provenance_casts)]
 //~^ WARNING unknown lint: `fuzzy_provenance_casts`
-//~| WARNING unknown lint: `fuzzy_provenance_casts`
-//~| WARNING unknown lint: `fuzzy_provenance_casts`
 #![deny(lossy_provenance_casts)]
 //~^ WARNING unknown lint: `lossy_provenance_casts`
-//~| WARNING unknown lint: `lossy_provenance_casts`
-//~| WARNING unknown lint: `lossy_provenance_casts`
 
 fn main() {
     // no warnings emitted since the lints are not activated
diff --git a/tests/ui/feature-gates/feature-gate-strict_provenance.stderr b/tests/ui/feature-gates/feature-gate-strict_provenance.stderr
index 1e6d762a540..36224ee864b 100644
--- a/tests/ui/feature-gates/feature-gate-strict_provenance.stderr
+++ b/tests/ui/feature-gates/feature-gate-strict_provenance.stderr
@@ -10,7 +10,7 @@ LL | #![deny(fuzzy_provenance_casts)]
    = note: `#[warn(unknown_lints)]` on by default
 
 warning: unknown lint: `lossy_provenance_casts`
-  --> $DIR/feature-gate-strict_provenance.rs:7:1
+  --> $DIR/feature-gate-strict_provenance.rs:5:1
    |
 LL | #![deny(lossy_provenance_casts)]
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -19,49 +19,5 @@ LL | #![deny(lossy_provenance_casts)]
    = note: see issue #95228 <https://github.com/rust-lang/rust/issues/95228> for more information
    = help: add `#![feature(strict_provenance)]` to the crate attributes to enable
 
-warning: unknown lint: `fuzzy_provenance_casts`
-  --> $DIR/feature-gate-strict_provenance.rs:3:1
-   |
-LL | #![deny(fuzzy_provenance_casts)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `fuzzy_provenance_casts` lint is unstable
-   = note: see issue #95228 <https://github.com/rust-lang/rust/issues/95228> for more information
-   = help: add `#![feature(strict_provenance)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `lossy_provenance_casts`
-  --> $DIR/feature-gate-strict_provenance.rs:7:1
-   |
-LL | #![deny(lossy_provenance_casts)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `lossy_provenance_casts` lint is unstable
-   = note: see issue #95228 <https://github.com/rust-lang/rust/issues/95228> for more information
-   = help: add `#![feature(strict_provenance)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `fuzzy_provenance_casts`
-  --> $DIR/feature-gate-strict_provenance.rs:3:1
-   |
-LL | #![deny(fuzzy_provenance_casts)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `fuzzy_provenance_casts` lint is unstable
-   = note: see issue #95228 <https://github.com/rust-lang/rust/issues/95228> for more information
-   = help: add `#![feature(strict_provenance)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `lossy_provenance_casts`
-  --> $DIR/feature-gate-strict_provenance.rs:7:1
-   |
-LL | #![deny(lossy_provenance_casts)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `lossy_provenance_casts` lint is unstable
-   = note: see issue #95228 <https://github.com/rust-lang/rust/issues/95228> for more information
-   = help: add `#![feature(strict_provenance)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 6 warnings emitted
+warning: 2 warnings emitted
 
diff --git a/tests/ui/feature-gates/feature-gate-test_unstable_lint.rs b/tests/ui/feature-gates/feature-gate-test_unstable_lint.rs
index c398394cbe1..3882ba9a227 100644
--- a/tests/ui/feature-gates/feature-gate-test_unstable_lint.rs
+++ b/tests/ui/feature-gates/feature-gate-test_unstable_lint.rs
@@ -3,7 +3,5 @@
 // `test_unstable_lint` is for testing and should never be stabilized.
 #![allow(test_unstable_lint)]
 //~^ WARNING unknown lint: `test_unstable_lint`
-//~| WARNING unknown lint: `test_unstable_lint`
-//~| WARNING unknown lint: `test_unstable_lint`
 
 fn main() {}
diff --git a/tests/ui/feature-gates/feature-gate-test_unstable_lint.stderr b/tests/ui/feature-gates/feature-gate-test_unstable_lint.stderr
index 562aa478a93..aec32ac4abb 100644
--- a/tests/ui/feature-gates/feature-gate-test_unstable_lint.stderr
+++ b/tests/ui/feature-gates/feature-gate-test_unstable_lint.stderr
@@ -8,25 +8,5 @@ LL | #![allow(test_unstable_lint)]
    = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
    = note: `#[warn(unknown_lints)]` on by default
 
-warning: unknown lint: `test_unstable_lint`
-  --> $DIR/feature-gate-test_unstable_lint.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `test_unstable_lint`
-  --> $DIR/feature-gate-test_unstable_lint.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/feature-gates/feature-gate-type_privacy_lints.rs b/tests/ui/feature-gates/feature-gate-type_privacy_lints.rs
index 8bb9736f1b4..80e51b265db 100644
--- a/tests/ui/feature-gates/feature-gate-type_privacy_lints.rs
+++ b/tests/ui/feature-gates/feature-gate-type_privacy_lints.rs
@@ -1,6 +1,4 @@
 // check-pass
 
 #![warn(unnameable_types)] //~ WARN unknown lint
-                           //~| WARN unknown lint
-                           //~| WARN unknown lint
 fn main() {}
diff --git a/tests/ui/feature-gates/feature-gate-type_privacy_lints.stderr b/tests/ui/feature-gates/feature-gate-type_privacy_lints.stderr
index 2614f2b3c35..5cc30de9c57 100644
--- a/tests/ui/feature-gates/feature-gate-type_privacy_lints.stderr
+++ b/tests/ui/feature-gates/feature-gate-type_privacy_lints.stderr
@@ -9,27 +9,5 @@ LL | #![warn(unnameable_types)]
    = help: add `#![feature(type_privacy_lints)]` to the crate attributes to enable
    = note: `#[warn(unknown_lints)]` on by default
 
-warning: unknown lint: `unnameable_types`
-  --> $DIR/feature-gate-type_privacy_lints.rs:3:1
-   |
-LL | #![warn(unnameable_types)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `unnameable_types` lint is unstable
-   = note: see issue #48054 <https://github.com/rust-lang/rust/issues/48054> for more information
-   = help: add `#![feature(type_privacy_lints)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `unnameable_types`
-  --> $DIR/feature-gate-type_privacy_lints.rs:3:1
-   |
-LL | #![warn(unnameable_types)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `unnameable_types` lint is unstable
-   = note: see issue #48054 <https://github.com/rust-lang/rust/issues/48054> for more information
-   = help: add `#![feature(type_privacy_lints)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/lint/crate_level_only_lint.rs b/tests/ui/lint/crate_level_only_lint.rs
index d9673faa214..6679cc0862f 100644
--- a/tests/ui/lint/crate_level_only_lint.rs
+++ b/tests/ui/lint/crate_level_only_lint.rs
@@ -3,20 +3,14 @@
 mod foo {
 #![allow(uncommon_codepoints)]
 //~^ ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
 
 #[allow(uncommon_codepoints)]
 //~^ ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
 const BAR: f64 = 0.000001;
 
 }
 
 #[allow(uncommon_codepoints)]
 //~^ ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
-//~| ERROR allow(uncommon_codepoints) is ignored unless specified at crate level [unused_attributes]
 fn main() {
 }
diff --git a/tests/ui/lint/crate_level_only_lint.stderr b/tests/ui/lint/crate_level_only_lint.stderr
index fbb1ec381c8..34d27f873f6 100644
--- a/tests/ui/lint/crate_level_only_lint.stderr
+++ b/tests/ui/lint/crate_level_only_lint.stderr
@@ -11,64 +11,16 @@ LL | #![deny(uncommon_codepoints, unused_attributes)]
    |                              ^^^^^^^^^^^^^^^^^
 
 error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:9:9
+  --> $DIR/crate_level_only_lint.rs:7:9
    |
 LL | #[allow(uncommon_codepoints)]
    |         ^^^^^^^^^^^^^^^^^^^
 
 error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:17:9
+  --> $DIR/crate_level_only_lint.rs:13:9
    |
 LL | #[allow(uncommon_codepoints)]
    |         ^^^^^^^^^^^^^^^^^^^
 
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:4:10
-   |
-LL | #![allow(uncommon_codepoints)]
-   |          ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:9:9
-   |
-LL | #[allow(uncommon_codepoints)]
-   |         ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:17:9
-   |
-LL | #[allow(uncommon_codepoints)]
-   |         ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:4:10
-   |
-LL | #![allow(uncommon_codepoints)]
-   |          ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:9:9
-   |
-LL | #[allow(uncommon_codepoints)]
-   |         ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(uncommon_codepoints) is ignored unless specified at crate level
-  --> $DIR/crate_level_only_lint.rs:17:9
-   |
-LL | #[allow(uncommon_codepoints)]
-   |         ^^^^^^^^^^^^^^^^^^^
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 9 previous errors
+error: aborting due to 3 previous errors
 
diff --git a/tests/ui/lint/forbid-group-group-2.rs b/tests/ui/lint/forbid-group-group-2.rs
index b12fd72da74..b3d3e30fb8d 100644
--- a/tests/ui/lint/forbid-group-group-2.rs
+++ b/tests/ui/lint/forbid-group-group-2.rs
@@ -11,16 +11,4 @@
 //~| WARNING previously accepted by the compiler
 //~| ERROR incompatible with previous
 //~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
-//~| ERROR incompatible with previous
-//~| WARNING previously accepted by the compiler
 fn main() {}
diff --git a/tests/ui/lint/forbid-group-group-2.stderr b/tests/ui/lint/forbid-group-group-2.stderr
index 4a2c8fbd68a..80e2f566eb8 100644
--- a/tests/ui/lint/forbid-group-group-2.stderr
+++ b/tests/ui/lint/forbid-group-group-2.stderr
@@ -41,83 +41,5 @@ LL | #[allow(nonstandard_style)]
    = note: for more information, see issue #81670 <https://github.com/rust-lang/rust/issues/81670>
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: allow(nonstandard_style) incompatible with previous forbid
-  --> $DIR/forbid-group-group-2.rs:7:9
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-...
-LL | #[allow(nonstandard_style)]
-   |         ^^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 9 previous errors
+error: aborting due to 3 previous errors
 
diff --git a/tests/ui/lint/forbid-group-member.rs b/tests/ui/lint/forbid-group-member.rs
index 664edeaa8b4..d03e858438b 100644
--- a/tests/ui/lint/forbid-group-member.rs
+++ b/tests/ui/lint/forbid-group-member.rs
@@ -8,10 +8,6 @@
 #[allow(unused_variables)]
 //~^ WARNING incompatible with previous forbid
 //~| WARNING previously accepted
-//~| WARNING incompatible with previous forbid
-//~| WARNING previously accepted
-//~| WARNING incompatible with previous forbid
-//~| WARNING previously accepted
 fn main() {
     let a: ();
 }
diff --git a/tests/ui/lint/forbid-group-member.stderr b/tests/ui/lint/forbid-group-member.stderr
index ddaaafa12ec..8794591bd31 100644
--- a/tests/ui/lint/forbid-group-member.stderr
+++ b/tests/ui/lint/forbid-group-member.stderr
@@ -11,31 +11,5 @@ LL | #[allow(unused_variables)]
    = note: for more information, see issue #81670 <https://github.com/rust-lang/rust/issues/81670>
    = note: `#[warn(forbidden_lint_groups)]` on by default
 
-warning: allow(unused_variables) incompatible with previous forbid
-  --> $DIR/forbid-group-member.rs:8:9
-   |
-LL | #![forbid(unused)]
-   |           ------ `forbid` level set here
-LL |
-LL | #[allow(unused_variables)]
-   |         ^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: allow(unused_variables) incompatible with previous forbid
-  --> $DIR/forbid-group-member.rs:8:9
-   |
-LL | #![forbid(unused)]
-   |           ------ `forbid` level set here
-LL |
-LL | #[allow(unused_variables)]
-   |         ^^^^^^^^^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/lint/forbid-member-group.rs b/tests/ui/lint/forbid-member-group.rs
index e2f76825a2d..d1874aa81a5 100644
--- a/tests/ui/lint/forbid-member-group.rs
+++ b/tests/ui/lint/forbid-member-group.rs
@@ -5,7 +5,6 @@
 
 #[allow(unused)]
 //~^ ERROR incompatible with previous forbid
-//~| ERROR incompatible with previous forbid
 fn main() {
     let a: ();
 }
diff --git a/tests/ui/lint/forbid-member-group.stderr b/tests/ui/lint/forbid-member-group.stderr
index 612dccd8d6c..9b32c00a3c3 100644
--- a/tests/ui/lint/forbid-member-group.stderr
+++ b/tests/ui/lint/forbid-member-group.stderr
@@ -7,17 +7,6 @@ LL |
 LL | #[allow(unused)]
    |         ^^^^^^ overruled by previous forbid
 
-error[E0453]: allow(unused) incompatible with previous forbid
-  --> $DIR/forbid-member-group.rs:6:9
-   |
-LL | #![forbid(unused_variables)]
-   |           ---------------- `forbid` level set here
-LL |
-LL | #[allow(unused)]
-   |         ^^^^^^ overruled by previous forbid
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0453`.
diff --git a/tests/ui/lint/issue-80988.rs b/tests/ui/lint/issue-80988.rs
index 1e116206f7b..5b910f1d8df 100644
--- a/tests/ui/lint/issue-80988.rs
+++ b/tests/ui/lint/issue-80988.rs
@@ -7,8 +7,4 @@
 #[deny(warnings)]
 //~^ WARNING incompatible with previous forbid
 //~| WARNING being phased out
-//~| WARNING incompatible with previous forbid
-//~| WARNING being phased out
-//~| WARNING incompatible with previous forbid
-//~| WARNING being phased out
 fn main() {}
diff --git a/tests/ui/lint/issue-80988.stderr b/tests/ui/lint/issue-80988.stderr
index 7a65881b5ed..afc93fcfeef 100644
--- a/tests/ui/lint/issue-80988.stderr
+++ b/tests/ui/lint/issue-80988.stderr
@@ -11,31 +11,5 @@ LL | #[deny(warnings)]
    = note: for more information, see issue #81670 <https://github.com/rust-lang/rust/issues/81670>
    = note: `#[warn(forbidden_lint_groups)]` on by default
 
-warning: deny(warnings) incompatible with previous forbid
-  --> $DIR/issue-80988.rs:7:8
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-LL |
-LL | #[deny(warnings)]
-   |        ^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: deny(warnings) incompatible with previous forbid
-  --> $DIR/issue-80988.rs:7:8
-   |
-LL | #![forbid(warnings)]
-   |           -------- `forbid` level set here
-LL |
-LL | #[deny(warnings)]
-   |        ^^^^^^^^ overruled by previous forbid
-   |
-   = 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 #81670 <https://github.com/rust-lang/rust/issues/81670>
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/lint/lint-forbid-attr.rs b/tests/ui/lint/lint-forbid-attr.rs
index 6d4cfd83424..270a379c2f8 100644
--- a/tests/ui/lint/lint-forbid-attr.rs
+++ b/tests/ui/lint/lint-forbid-attr.rs
@@ -2,6 +2,5 @@
 
 #[allow(deprecated)]
 //~^ ERROR allow(deprecated) incompatible
-//~| ERROR allow(deprecated) incompatible
 fn main() {
 }
diff --git a/tests/ui/lint/lint-forbid-attr.stderr b/tests/ui/lint/lint-forbid-attr.stderr
index bd476a0e362..fa7106b5e11 100644
--- a/tests/ui/lint/lint-forbid-attr.stderr
+++ b/tests/ui/lint/lint-forbid-attr.stderr
@@ -7,17 +7,6 @@ LL |
 LL | #[allow(deprecated)]
    |         ^^^^^^^^^^ overruled by previous forbid
 
-error[E0453]: allow(deprecated) incompatible with previous forbid
-  --> $DIR/lint-forbid-attr.rs:3:9
-   |
-LL | #![forbid(deprecated)]
-   |           ---------- `forbid` level set here
-LL |
-LL | #[allow(deprecated)]
-   |         ^^^^^^^^^^ overruled by previous forbid
-   |
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0453`.
diff --git a/tests/ui/lint/lint-forbid-cmdline.rs b/tests/ui/lint/lint-forbid-cmdline.rs
index 5246ccb57a6..32a92e09b14 100644
--- a/tests/ui/lint/lint-forbid-cmdline.rs
+++ b/tests/ui/lint/lint-forbid-cmdline.rs
@@ -1,6 +1,5 @@
 // compile-flags: -F deprecated
 
 #[allow(deprecated)] //~ ERROR allow(deprecated) incompatible
-                     //~| ERROR allow(deprecated) incompatible
 fn main() {
 }
diff --git a/tests/ui/lint/lint-forbid-cmdline.stderr b/tests/ui/lint/lint-forbid-cmdline.stderr
index ed49a2cb427..3920a742976 100644
--- a/tests/ui/lint/lint-forbid-cmdline.stderr
+++ b/tests/ui/lint/lint-forbid-cmdline.stderr
@@ -6,15 +6,6 @@ LL | #[allow(deprecated)]
    |
    = note: `forbid` lint level was set on command line
 
-error[E0453]: allow(deprecated) incompatible with previous forbid
-  --> $DIR/lint-forbid-cmdline.rs:3:9
-   |
-LL | #[allow(deprecated)]
-   |         ^^^^^^^^^^ overruled by previous forbid
-   |
-   = note: `forbid` lint level was set on command line
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 2 previous errors
+error: aborting due to 1 previous error
 
 For more information about this error, try `rustc --explain E0453`.
diff --git a/tests/ui/lint/must_not_suspend/gated.rs b/tests/ui/lint/must_not_suspend/gated.rs
index b73a7655529..fe8192b0eaa 100644
--- a/tests/ui/lint/must_not_suspend/gated.rs
+++ b/tests/ui/lint/must_not_suspend/gated.rs
@@ -3,8 +3,6 @@
 // edition:2018
 #![deny(must_not_suspend)]
 //~^ WARNING unknown lint: `must_not_suspend`
-//~| WARNING unknown lint: `must_not_suspend`
-//~| WARNING unknown lint: `must_not_suspend`
 
 async fn other() {}
 
diff --git a/tests/ui/lint/must_not_suspend/gated.stderr b/tests/ui/lint/must_not_suspend/gated.stderr
index f0d2117d42b..c238c1f3351 100644
--- a/tests/ui/lint/must_not_suspend/gated.stderr
+++ b/tests/ui/lint/must_not_suspend/gated.stderr
@@ -9,27 +9,5 @@ LL | #![deny(must_not_suspend)]
    = help: add `#![feature(must_not_suspend)]` to the crate attributes to enable
    = note: `#[warn(unknown_lints)]` on by default
 
-warning: unknown lint: `must_not_suspend`
-  --> $DIR/gated.rs:4:1
-   |
-LL | #![deny(must_not_suspend)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `must_not_suspend` lint is unstable
-   = note: see issue #83310 <https://github.com/rust-lang/rust/issues/83310> for more information
-   = help: add `#![feature(must_not_suspend)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `must_not_suspend`
-  --> $DIR/gated.rs:4:1
-   |
-LL | #![deny(must_not_suspend)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `must_not_suspend` lint is unstable
-   = note: see issue #83310 <https://github.com/rust-lang/rust/issues/83310> for more information
-   = help: add `#![feature(must_not_suspend)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/unknown-unstable-lints/deny-unstable-lint-command-line.stderr b/tests/ui/unknown-unstable-lints/deny-unstable-lint-command-line.stderr
index f0450aea49a..df83c103084 100644
--- a/tests/ui/unknown-unstable-lints/deny-unstable-lint-command-line.stderr
+++ b/tests/ui/unknown-unstable-lints/deny-unstable-lint-command-line.stderr
@@ -4,17 +4,5 @@ error: unknown lint: `test_unstable_lint`
    = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
    = note: requested on the command line with `-D unknown-lints`
 
-error: unknown lint: `test_unstable_lint`
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: unknown lint: `test_unstable_lint`
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 3 previous errors
+error: aborting due to 1 previous error
 
diff --git a/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.rs b/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.rs
index c6c60b12d83..29c6547abc1 100644
--- a/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.rs
+++ b/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.rs
@@ -3,7 +3,5 @@
 #![deny(unknown_lints)]
 #![allow(test_unstable_lint)]
 //~^ ERROR unknown lint: `test_unstable_lint`
-//~| ERROR unknown lint: `test_unstable_lint`
-//~| ERROR unknown lint: `test_unstable_lint`
 
 fn main() {}
diff --git a/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.stderr b/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.stderr
index 20a36b28dc6..0afe3d55c98 100644
--- a/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.stderr
+++ b/tests/ui/unknown-unstable-lints/deny-unstable-lint-inline.stderr
@@ -12,25 +12,5 @@ note: the lint level is defined here
 LL | #![deny(unknown_lints)]
    |         ^^^^^^^^^^^^^
 
-error: unknown lint: `test_unstable_lint`
-  --> $DIR/deny-unstable-lint-inline.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: unknown lint: `test_unstable_lint`
-  --> $DIR/deny-unstable-lint-inline.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-error: aborting due to 3 previous errors
+error: aborting due to 1 previous error
 
diff --git a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-command-line.stderr b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-command-line.stderr
index a2deecf1caf..c133b880ebd 100644
--- a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-command-line.stderr
+++ b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-command-line.stderr
@@ -4,17 +4,5 @@ warning: unknown lint: `test_unstable_lint`
    = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
    = note: requested on the command line with `-W unknown-lints`
 
-warning: unknown lint: `test_unstable_lint`
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `test_unstable_lint`
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `-Zcrate-attr="feature(test_unstable_lint)"` to the command-line options to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted
 
diff --git a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.rs b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.rs
index f4247e4569e..89db84e69f6 100644
--- a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.rs
+++ b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.rs
@@ -3,7 +3,5 @@
 #![warn(unknown_lints)]
 #![allow(test_unstable_lint)]
 //~^ WARNING unknown lint: `test_unstable_lint`
-//~| WARNING unknown lint: `test_unstable_lint`
-//~| WARNING unknown lint: `test_unstable_lint`
 
 fn main() {}
diff --git a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.stderr b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.stderr
index 12afb2e294a..48c83b49e29 100644
--- a/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.stderr
+++ b/tests/ui/unknown-unstable-lints/warn-unknown-unstable-lint-inline.stderr
@@ -12,25 +12,5 @@ note: the lint level is defined here
 LL | #![warn(unknown_lints)]
    |         ^^^^^^^^^^^^^
 
-warning: unknown lint: `test_unstable_lint`
-  --> $DIR/warn-unknown-unstable-lint-inline.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: unknown lint: `test_unstable_lint`
-  --> $DIR/warn-unknown-unstable-lint-inline.rs:4:1
-   |
-LL | #![allow(test_unstable_lint)]
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the `test_unstable_lint` lint is unstable
-   = help: add `#![feature(test_unstable_lint)]` to the crate attributes to enable
-   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-
-warning: 3 warnings emitted
+warning: 1 warning emitted