diff --git a/lib/dns/include/dns/rbt.h b/lib/dns/include/dns/rbt.h
index 95e9fbfcec..3ea3021aa7 100644
--- a/lib/dns/include/dns/rbt.h
+++ b/lib/dns/include/dns/rbt.h
@@ -681,7 +681,7 @@ dns_rbt_destroy2(dns_rbt_t **rbtp, unsigned int quantum);
  * \li  ISC_R_QUOTA if 'quantum' nodes have been destroyed.
  */
 
-inline long
+long
 dns_rbt_serialize_align(long target);
 /*%<
  * Align the provided integer to a pointer-size boundary.
diff --git a/lib/dns/rbt.c b/lib/dns/rbt.c
index 49f4b0d501..f3e0a09529 100644
--- a/lib/dns/rbt.c
+++ b/lib/dns/rbt.c
@@ -546,7 +546,7 @@ serialize_nodes(FILE *file, dns_rbtnode_t *node, uintptr_t parent,
 	return (result);
 }
 
-inline long
+long
 dns_rbt_serialize_align(long target) {
 	long offset = target % 8;