Passed through clippy.

crates/env/src/api.rs

@@ -211,7 +211,7 @@ where
     V: Storable,
     Ref: ink_storage_traits::StorageLayout,
 {
-    let x = Ref::layout as u64;
+    let x = Ref::layout as usize;
     let x = ((x | (x >> 32)) & 0xFFFFFFFF) as u32;
     set_contract_storage(&x, value)
 }
@@ -466,7 +466,7 @@ where
 /// When the test_instantiate feature is used, the contract is allowed to
 /// return normally. This feature should only be used for integration tests.
 #[cfg(feature = "test_instantiate")]
-pub fn return_value<R>(return_flags: ReturnFlags, return_value: &R) -> ()
+pub fn return_value<R>(return_flags: ReturnFlags, return_value: &R)
 where
     R: scale::Encode,
 {

crates/env/src/backend.rs

@@ -262,7 +262,7 @@ pub trait EnvBackend {
     /// The `flags` parameter can be used to revert the state changes of the
     /// entire execution if necessary.
     #[cfg(feature = "test_instantiate")]
-    fn return_value<R>(&mut self, flags: ReturnFlags, return_value: &R) -> ()
+    fn return_value<R>(&mut self, flags: ReturnFlags, return_value: &R)
     where
         R: scale::Encode;
 

crates/env/src/engine/off_chain/impls.rs

@@ -260,7 +260,7 @@ impl EnvBackend for EnvInstance {
     }
 
     #[cfg(feature = "test_instantiate")]
-    fn return_value<R>(&mut self, _flags: ReturnFlags, return_value: &R) -> ()
+    fn return_value<R>(&mut self, _flags: ReturnFlags, return_value: &R)
     where
         R: scale::Encode,
     {