--- a/source4/dsdb/samdb/ldb_modules/count_attrs.c
+++ b/source4/dsdb/samdb/ldb_modules/count_attrs.c
@@ -40,6 +40,11 @@
 
 #undef strcasecmp
 
+#ifndef __COMPAR_FN_T
+#define __COMPAR_FN_T
+typedef int (*__compar_fn_t)(const void *, const void *);
+#endif
+
 struct count_attrs_private {
 	struct tdb_wrap *requested;
 	struct tdb_wrap *duplicates;