omit unused args warnings for intrinsics without body

1 files changed, 8 insertions, 0 deletions

diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs
index b85a987c641..279729365ee 100644
--- a/compiler/rustc_passes/src/liveness.rs
+++ b/compiler/rustc_passes/src/liveness.rs
@@ -1521,6 +1521,14 @@ impl<'tcx> Liveness<'_, 'tcx> {
     }
 
     fn warn_about_unused_args(&self, body: &hir::Body<'_>, entry_ln: LiveNode) {
+        if let Some(intrinsic) =
+            self.ir.tcx.intrinsic(self.ir.tcx.hir().body_owner_def_id(body.id()))
+        {
+            if intrinsic.must_be_overridden {
+                return;
+            }
+        }
+
         for p in body.params {
             self.check_unused_vars_in_pat(
                 p.pat,