From faddfb500118d3f1ad5bd8a87a26613aff490261 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <contact@guillaume-gomez.fr>
Date: Sun, 22 Mar 2026 18:34:43 +0100
Subject: [PATCH] Add new `LintBuffer::dyn_buffer_lint` method

---
 compiler/rustc_errors/src/decorate_diag.rs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/compiler/rustc_errors/src/decorate_diag.rs b/compiler/rustc_errors/src/decorate_diag.rs
index a11082e29663..c7e0d508c173 100644
--- a/compiler/rustc_errors/src/decorate_diag.rs
+++ b/compiler/rustc_errors/src/decorate_diag.rs
@@ -81,4 +81,21 @@ pub fn buffer_lint(
             diagnostic: decorate.into(),
         });
     }
+
+    pub fn dyn_buffer_lint<
+        F: for<'a> FnOnce(DiagCtxtHandle<'a>, Level) -> Diag<'a, ()> + DynSend + 'static,
+    >(
+        &mut self,
+        lint: &'static Lint,
+        node_id: NodeId,
+        span: impl Into<MultiSpan>,
+        callback: F,
+    ) {
+        self.add_early_lint(BufferedEarlyLint {
+            lint_id: LintId::of(lint),
+            node_id,
+            span: Some(span.into()),
+            diagnostic: DecorateDiagCompat::Dynamic(Box::new(callback)),
+        });
+    }
 }