fix clang-14

Author: bernhardmgruber

thrust/testing/device_ptr.cu

@@ -3,12 +3,14 @@
 
 #include <cuda/std/iterator>
 
+#include <iterator>
+
 #include <unittest/unittest.h>
 
-#if _CCCL_STD_VER >= 2020
+#if _CCCL_STD_VER >= 2020 && defined(__cpp_lib_concepts)
 static_assert(std::indirectly_writable<thrust::device_ptr<uint8_t>, uint8_t>);
+#endif // _CCCL_STD_VER >= 2020 && defined(__cpp_lib_concepts)
 static_assert(cuda::std::indirectly_writable<thrust::device_ptr<uint8_t>, uint8_t>);
-#endif // _CCCL_STD_VER >= 2020
 
 void TestDevicePointerManipulation()
 {