From ddad55f6c214357f48134d00050c6dbfcf1d9215 Mon Sep 17 00:00:00 2001
From: blyxyas <blyxyas@gmail.com>
Date: Tue, 15 Oct 2024 22:15:07 +0200
Subject: [PATCH] Apply review comments + use `shallow_lint_levels_on`

---
 compiler/rustc_lint/src/late.rs           |  2 +-
 compiler/rustc_lint/src/levels.rs         | 20 +++++++++++++++-----
 compiler/rustc_lint_defs/src/lib.rs       | 11 -----------
 src/tools/clippy/clippy_lints/src/ctfe.rs |  2 +-
 src/tools/clippy/clippy_lints/src/lib.rs  |  2 +-
 5 files changed, 18 insertions(+), 19 deletions(-)

diff --git a/compiler/rustc_lint/src/late.rs b/compiler/rustc_lint/src/late.rs
index ea7a44dd123..9b1877599ba 100644
--- a/compiler/rustc_lint/src/late.rs
+++ b/compiler/rustc_lint/src/late.rs
@@ -432,7 +432,7 @@ fn late_lint_crate<'tcx>(tcx: TyCtxt<'tcx>) {
     let mut filtered_passes: Vec<Box<dyn LateLintPass<'tcx>>> = passes
         .into_iter()
         .filter(|pass| {
-            let lints = LintPass::get_lints(pass);
+            let lints = (**pass).get_lints();
             !lints.iter().all(|lint| lints_that_dont_need_to_run.contains(&LintId::of(lint)))
         })
         .collect();
diff --git a/compiler/rustc_lint/src/levels.rs b/compiler/rustc_lint/src/levels.rs
index 64e1cddf248..2c12899fad0 100644
--- a/compiler/rustc_lint/src/levels.rs
+++ b/compiler/rustc_lint/src/levels.rs
@@ -2,8 +2,8 @@
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_errors::{Diag, LintDiagnostic, MultiSpan};
 use rustc_feature::{Features, GateIssue};
-use rustc_hir::HirId;
 use rustc_hir::intravisit::{self, Visitor};
+use rustc_hir::{CRATE_HIR_ID, HirId};
 use rustc_index::IndexVec;
 use rustc_middle::bug;
 use rustc_middle::hir::nested_filter;
@@ -118,12 +118,22 @@ fn raw_lint_id_level(
 fn lints_that_dont_need_to_run(tcx: TyCtxt<'_>, (): ()) -> FxIndexSet<LintId> {
     let store = unerased_lint_store(&tcx.sess);
 
+    let map = tcx.shallow_lint_levels_on(rustc_hir::CRATE_OWNER_ID);
+
     let dont_need_to_run: FxIndexSet<LintId> = store
         .get_lints()
         .into_iter()
         .filter_map(|lint| {
-            if !lint.eval_always && lint.default_level(tcx.sess.edition()) == Level::Allow {
-                Some(LintId::of(lint))
+            if !lint.eval_always {
+                let lint_level = map.lint_level_id_at_node(tcx, LintId::of(lint), CRATE_HIR_ID);
+                if matches!(lint_level, (Level::Allow, ..))
+                    || (matches!(lint_level, (.., LintLevelSource::Default)))
+                        && lint.default_level(tcx.sess.edition()) == Level::Allow
+                {
+                    Some(LintId::of(lint))
+                } else {
+                    None
+                }
             } else {
                 None
             }
@@ -372,7 +382,7 @@ fn visit_attribute(&mut self, attribute: &'tcx ast::Attribute) {
         ) {
             let store = unerased_lint_store(self.tcx.sess);
             let Some(meta) = attribute.meta() else { return };
-            // SAFETY: Lint attributes are always a metalist inside a
+            // Lint attributes are always a metalist inside a
             // metalist (even with just one lint).
             let Some(meta_item_list) = meta.meta_item_list() else { return };
 
@@ -387,7 +397,7 @@ fn visit_attribute(&mut self, attribute: &'tcx ast::Attribute) {
                     .collect::<Vec<&str>>()
                     .join("::");
                 let Ok(lints) = store.find_lints(
-                    // SAFETY: Lint attributes can only have literals
+                    // Lint attributes can only have literals
                     ident,
                 ) else {
                     return;
diff --git a/compiler/rustc_lint_defs/src/lib.rs b/compiler/rustc_lint_defs/src/lib.rs
index 320668a5dbf..418caa699e2 100644
--- a/compiler/rustc_lint_defs/src/lib.rs
+++ b/compiler/rustc_lint_defs/src/lib.rs
@@ -968,14 +968,3 @@ macro_rules! declare_lint_pass {
         $crate::impl_lint_pass!($name => [$($lint),*]);
     };
 }
-
-#[allow(rustc::lint_pass_impl_without_macro)]
-impl<P: LintPass + ?Sized> LintPass for Box<P> {
-    fn name(&self) -> &'static str {
-        (**self).name()
-    }
-
-    fn get_lints(&self) -> LintVec {
-        (**self).get_lints()
-    }
-}
diff --git a/src/tools/clippy/clippy_lints/src/ctfe.rs b/src/tools/clippy/clippy_lints/src/ctfe.rs
index ddb4eb82165..93d0ad789be 100644
--- a/src/tools/clippy/clippy_lints/src/ctfe.rs
+++ b/src/tools/clippy/clippy_lints/src/ctfe.rs
@@ -7,7 +7,7 @@
 use rustc_span::Span;
 
 /// Ensures that Constant-time Function Evaluation is being done (specifically, MIR lint passes).
-/// See rust-lang/rust#125116 for more info.
+/// As Clippy deactivates codegen, this lint ensures that CTFE (used in hard errors) is still ran.
 #[clippy::version = "1.82.0"]
 pub static CLIPPY_CTFE: &Lint = &Lint {
     name: &"clippy::CLIPPY_CTFE",
diff --git a/src/tools/clippy/clippy_lints/src/lib.rs b/src/tools/clippy/clippy_lints/src/lib.rs
index 88a227f5b6d..14110539709 100644
--- a/src/tools/clippy/clippy_lints/src/lib.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.rs
@@ -65,7 +65,7 @@
 #[cfg_attr(feature = "internal", allow(clippy::missing_clippy_version_attribute))]
 mod utils;
 
-pub mod ctfe; // Very important lint (rust#125116)
+pub mod ctfe; // Very important lint, do not remove (rust#125116)
 pub mod declared_lints;
 pub mod deprecated_lints;