Remove unused span argument from walk_fn.

Author: nnethercote

clippy_lints/src/derive.rs

@@ -425,7 +425,7 @@ struct UnsafeVisitor<'a, 'tcx> {
 impl<'tcx> Visitor<'tcx> for UnsafeVisitor<'_, 'tcx> {
     type NestedFilter = nested_filter::All;
 
-    fn visit_fn(&mut self, kind: FnKind<'tcx>, decl: &'tcx FnDecl<'_>, body_id: BodyId, span: Span, id: HirId) {
+    fn visit_fn(&mut self, kind: FnKind<'tcx>, decl: &'tcx FnDecl<'_>, body_id: BodyId, _: Span, id: HirId) {
         if self.has_unsafe {
             return;
         }
@@ -438,7 +438,7 @@ impl<'tcx> Visitor<'tcx> for UnsafeVisitor<'_, 'tcx> {
             }
         }
 
-        walk_fn(self, kind, decl, body_id, span, id);
+        walk_fn(self, kind, decl, body_id, id);
     }
 
     fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {

clippy_lints/src/unused_async.rs

@@ -70,7 +70,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedAsync {
     ) {
         if !span.from_expansion() && fn_kind.asyncness() == IsAsync::Async {
             let mut visitor = AsyncFnVisitor { cx, found_await: false };
-            walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), span, hir_id);
+            walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), hir_id);
             if !visitor.found_await {
                 span_lint_and_help(
                     cx,

clippy_lints/src/unwrap.rs

@@ -326,6 +326,6 @@ impl<'tcx> LateLintPass<'tcx> for Unwrap {
             unwrappables: Vec::new(),
         };
 
-        walk_fn(&mut v, kind, decl, body.id(), span, fn_id);
+        walk_fn(&mut v, kind, decl, body.id(), fn_id);
     }
 }