diff --git a/keystore2/apc_compat/apc_compat.rs b/keystore2/apc_compat/apc_compat.rs
index 57f8710..480f14d 100644
--- a/keystore2/apc_compat/apc_compat.rs
+++ b/keystore2/apc_compat/apc_compat.rs
@@ -19,7 +19,7 @@
 //! client.
 
 use keystore2_apc_compat_bindgen::{
-    abortUserConfirmation, closeUserConfirmationService, promptUserConfirmation, size_t,
+    abortUserConfirmation, closeUserConfirmationService, promptUserConfirmation,
     tryGetUserConfirmationService, ApcCompatCallback, ApcCompatServiceHandle,
 };
 pub use keystore2_apc_compat_bindgen::{
@@ -76,9 +76,9 @@
     handle: *mut ::std::os::raw::c_void,
     rc: u32,
     tbs_message: *const u8,
-    tbs_message_size: size_t,
+    tbs_message_size: usize,
     confirmation_token: *const u8,
-    confirmation_token_size: size_t,
+    confirmation_token_size: usize,
 ) {
     // # Safety:
     // The C/C++ implementation must pass to us the handle that was created
@@ -94,7 +94,7 @@
             // If the pointer and size is not nullptr and not 0 respectively, the C/C++
             // implementation must pass a valid pointer to an allocation of at least size bytes,
             // and the pointer must be valid until this function returns.
-            unsafe { slice::from_raw_parts(tbs_message, s as usize) },
+            unsafe { slice::from_raw_parts(tbs_message, s) },
         ),
     };
     let confirmation_token = match (confirmation_token.is_null(), confirmation_token_size) {
@@ -104,7 +104,7 @@
             // If the pointer and size is not nullptr and not 0 respectively, the C/C++
             // implementation must pass a valid pointer to an allocation of at least size bytes,
             // and the pointer must be valid until this function returns.
-            unsafe { slice::from_raw_parts(confirmation_token, s as usize) },
+            unsafe { slice::from_raw_parts(confirmation_token, s) },
         ),
     };
     hal_cb(rc, tbs_message, confirmation_token)
@@ -178,7 +178,7 @@
                 cb,
                 prompt_text.as_ptr(),
                 extra_data.as_ptr(),
-                extra_data.len() as size_t,
+                extra_data.len(),
                 locale.as_ptr(),
                 ui_opts,
             )