Fix warnings it tests

src/test/debug-info/tuple-in-struct.rs

@@ -41,6 +41,8 @@
 // debugger:print mixed_padding
 // check:$10 = {x = {{40, 41, 42}, {43, 44}}, y = {45, 46, 47, 48}}
 
+#[allow(unused_variable)];
+
 struct NoPadding1 {
     x: (i32, i32),
     y: i32,
@@ -148,4 +150,4 @@ fn main() {
     zzz();
 }
 
-fn zzz() {()}
+fn zzz() {()}