diff --git a/ssl/ssltest.c b/ssl/ssltest.c
index 2f5a13439..7a758f028 100644
--- a/ssl/ssltest.c
+++ b/ssl/ssltest.c
@@ -116,6 +116,7 @@
 
 /* Or gethostname won't be declared properly on Linux and GNU platforms. */
 #define _BSD_SOURCE 1
+#define _DEFAULT_SOURCE 1
 
 #include <assert.h>
 #include <errno.h>