@@ -24,9 +24,10 @@
 #import "macros.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
-extern uint32_t of_crc32(uint32_t crc, unsigned char *bytes, size_t length);
+extern uint32_t of_crc32(uint32_t crc, unsigned char *_Nonnull bytes,
+    size_t length);
 #ifdef __cplusplus
 }
 #endif