diff --git a/sample/dns-example.c b/sample/dns-example.c
index e555af56..439a486a 100644
--- a/sample/dns-example.c
+++ b/sample/dns-example.c
@@ -7,6 +7,7 @@
 
 #include <event2/event-config.h>
 
+/* Compatibility for possible missing IPv6 declarations */
 #include "../ipv6-internal.h"
 
 #include <sys/types.h>
diff --git a/sample/http-server.c b/sample/http-server.c
index 76026a51..d5212c51 100644
--- a/sample/http-server.c
+++ b/sample/http-server.c
@@ -41,6 +41,7 @@
 # endif
 #endif
 
+/* Compatibility for possible missing IPv6 declarations */
 #include "../util-internal.h"
 
 #ifdef WIN32