fix rustdoc ICE

Author: estebank

compiler/rustc_lint/src/default_could_be_derived.rs

@@ -481,6 +481,13 @@ fn check_path<'tcx>(
     let instance = Instance::try_resolve(cx.tcx, cx.typing_env(), default_fn_def_id, args);
 
     let Ok(Some(instance)) = instance else { return false };
+    if let ty::InstanceKind::Item(def) = instance.def
+        && !cx.tcx.is_mir_available(def)
+    {
+        // Avoid ICE while running rustdoc for not providing `optimized_mir` query.
+        return false;
+    }
+
     // Get the MIR Body for the `<FieldTy as Default>::default()` function.
     // If it is a value or call (either fn or ctor), we compare its DefId against the one for the
     // resolution of the expression we had in the path. This lets us identify, for example, that