Merge commit '0621446356' into clippy-subtree-update

tests/ui/default_constructed_unit_structs.fixed

@@ -161,3 +161,17 @@ fn main() {
 
     let _ = <struct_from_macro!()>::default();
 }
+
+fn issue12654() {
+    #[derive(Default)]
+    struct G;
+
+    fn f(_g: G) {}
+
+    f(<_>::default());
+    f(G);
+    //~^ default_constructed_unit_structs
+
+    // No lint because `as Default` hides the singleton
+    f(<G as Default>::default());
+}