Add variable reference to quash gcc warning with -DNDEBUG.

diff --git a/src/mail-smtp.c b/src/mail-smtp.c
index 85b68d9f2be9b53147e637b502f046deb4fd4250..13a6c383d7969a9ee305e6fedc3b47460f895f3f 100644 (file)
--- a/src/mail-smtp.c
+++ b/src/mail-smtp.c
@@ -383,6 +383,7 @@ static void mail_destroyed(struct io_fd *fd)
     assert(smtp_fd == fd);
     smtp_state = CLOSED;
     smtp_fd = NULL;
+    (void)fd; /* in case NDEBUG causes assert() to be empty */
 }
 
 static void mail_connected(struct io_fd *fd, int error)