diff --git a/libssh/poll.c b/libssh/poll.c
index 50ce0062..8aeebb42 100644
--- a/libssh/poll.c
+++ b/libssh/poll.c
@@ -133,7 +133,7 @@ static int bsd_poll(ssh_pollfd_t *fds, nfds_t nfds, int timeout) {
       }
   }
 
-  if (max_fd == SSH_INVALID_SOCKET || rc = -1) {
+  if (max_fd == SSH_INVALID_SOCKET || rc == -1) {
       errno = EINVAL;
       return -1;
   }