avoid some int2ptr casts in thread_local_key tests

library/std/src/sys_common/thread_local_key/tests.rs

@@ -1,4 +1,5 @@
 use super::{Key, StaticKey};
+use core::ptr;
 
 fn assert_sync<T: Sync>() {}
 fn assert_send<T: Send>() {}
@@ -12,8 +13,8 @@ fn smoke() {
     let k2 = Key::new(None);
     assert!(k1.get().is_null());
     assert!(k2.get().is_null());
-    k1.set(1 as *mut _);
-    k2.set(2 as *mut _);
+    k1.set(ptr::invalid_mut(1));
+    k2.set(ptr::invalid_mut(2));
     assert_eq!(k1.get() as usize, 1);
     assert_eq!(k2.get() as usize, 2);
 }
@@ -26,8 +27,8 @@ fn statik() {
     unsafe {
         assert!(K1.get().is_null());
         assert!(K2.get().is_null());
-        K1.set(1 as *mut _);
-        K2.set(2 as *mut _);
+        K1.set(ptr::invalid_mut(1));
+        K2.set(ptr::invalid_mut(2));
         assert_eq!(K1.get() as usize, 1);
         assert_eq!(K2.get() as usize, 2);
     }