Error out on unknown debug flag

Otehrwise it's pretty easy to misremember a flag and think damage=rerender is
enabled when it's not.

1 files changed, 2 insertions, 0 deletions

diff --git a/sway/main.c b/sway/main.c
index 9ddbea81..177c0aa1 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -211,6 +211,8 @@ void enable_debug_flag(const char *flag) {
                 debug.txn_timings = true;
         } else if (strncmp(flag, "txn-timeout=", 12) == 0) {
                 server.txn_timeout_ms = atoi(&flag[12]);
+        } else {
+                sway_log(SWAY_ERROR, "Unknown debug flag: %s", flag);
         }
 }