diff --git a/backend/session/logind.c b/backend/session/logind.c
index 066003d9..393924e8 100644
--- a/backend/session/logind.c
+++ b/backend/session/logind.c
@@ -258,6 +258,7 @@ static struct wlr_device *find_device(struct wlr_session *session,
 	wlr_log(WLR_ERROR, "Tried to use dev_t %lu not opened by session",
 		(unsigned long)devnum);
 	assert(0);
+	return NULL;
 }
 
 static int pause_device(sd_bus_message *msg, void *userdata,
diff --git a/backend/session/session.c b/backend/session/session.c
index 70b4a567..a98093c7 100644
--- a/backend/session/session.c
+++ b/backend/session/session.c
@@ -197,6 +197,7 @@ static struct wlr_device *find_device(struct wlr_session *session, int fd) {
 
 	wlr_log(WLR_ERROR, "Tried to use fd %d not opened by session", fd);
 	assert(0);
+	return NULL;
 }
 
 void wlr_session_close_file(struct wlr_session *session, int fd) {