diff --git a/kotlin-native/backend.native/tests/interop/objc/direct/direct.h b/kotlin-native/backend.native/tests/interop/objc/direct/direct.h
index 666439b387f..af73d44d981 100644
--- a/kotlin-native/backend.native/tests/interop/objc/direct/direct.h
+++ b/kotlin-native/backend.native/tests/interop/objc/direct/direct.h
@@ -6,21 +6,21 @@ __attribute__((objc_runtime_name("CC")))
 __attribute__((swift_name("CC")))
 @interface CallingConventions : NSObject
 
-+ (NSUInteger)regular:(NSUInteger)arg;
-- (NSUInteger)regular:(NSUInteger)arg;
++ (uint64_t)regular:(uint64_t)arg;
+- (uint64_t)regular:(uint64_t)arg;
 
-+ (NSUInteger)direct:(NSUInteger)arg __attribute__((objc_direct));
-- (NSUInteger)direct:(NSUInteger)arg __attribute__((objc_direct));
++ (uint64_t)direct:(uint64_t)arg __attribute__((objc_direct));
+- (uint64_t)direct:(uint64_t)arg __attribute__((objc_direct));
 
 @end
 
 @interface CallingConventions(Ext)
 
-+ (NSUInteger)regularExt:(NSUInteger)arg;
-- (NSUInteger)regularExt:(NSUInteger)arg;
++ (uint64_t)regularExt:(uint64_t)arg;
+- (uint64_t)regularExt:(uint64_t)arg;
 
-+ (NSUInteger)directExt:(NSUInteger)arg __attribute__((objc_direct));
-- (NSUInteger)directExt:(NSUInteger)arg __attribute__((objc_direct));
++ (uint64_t)directExt:(uint64_t)arg __attribute__((objc_direct));
+- (uint64_t)directExt:(uint64_t)arg __attribute__((objc_direct));
 
 @end
 
diff --git a/kotlin-native/backend.native/tests/interop/objc/direct/direct.m b/kotlin-native/backend.native/tests/interop/objc/direct/direct.m
index 5d6a7f7efb6..ce893b1c9c6 100644
--- a/kotlin-native/backend.native/tests/interop/objc/direct/direct.m
+++ b/kotlin-native/backend.native/tests/interop/objc/direct/direct.m
@@ -1,6 +1,6 @@
 #import "direct.h"
 
-#define TEST_METHOD_IMPL(NAME) (NSUInteger)NAME:(NSUInteger)arg { return arg; }
+#define TEST_METHOD_IMPL(NAME) (uint64_t)NAME:(uint64_t)arg { return arg; }
 
 @implementation CallingConventions : NSObject