diff --git a/src/libiso8601/400_leap.h b/src/libiso8601/400_leap.h
index 2797464..f9bb4ca 100644
--- a/src/libiso8601/400_leap.h
+++ b/src/libiso8601/400_leap.h
@@ -124,11 +124,7 @@ be set appropriately. If \a errno is \c EINVAL, then the file does not contain
 a valid leap second table.
 
 */
-int iso8601_leap_table_load(const char* fname)
-#ifndef DOXYGEN
-    __attribute__((nonnull))
-#endif
-;
+int iso8601_leap_table_load(const char* fname);