diff --git a/src/config.h.in b/src/config.h.in
index b9111250d4..50d29f5513 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -29,9 +29,6 @@
 /* Define if you have the <sys/poll.h> header file */
 #undef HAVE_SYS_POLL_H
 
-/* Define if you have the `setvbuf' function. */
-#undef HAVE_SETVBUF
-
 /* Define if you have the `poll' function. */
 #undef HAVE_POLL