--- a/rsync.h
+++ b/rsync.h
@@ -307,6 +307,7 @@ enum delret {
 #include <stdio.h>
 #ifdef HAVE_SYS_TYPES_H
 # include <sys/types.h>
+# include <sys/sysmacros.h>
 #endif
 #ifdef HAVE_SYS_STAT_H
 # include <sys/stat.h>