diff --git a/renderdoc/driver/vulkan/vk_replay.h b/renderdoc/driver/vulkan/vk_replay.h
index 4f4e29d12..11592b980 100644
--- a/renderdoc/driver/vulkan/vk_replay.h
+++ b/renderdoc/driver/vulkan/vk_replay.h
@@ -47,6 +47,10 @@
 #define WINDOW_HANDLE_DECL xcb_connection_t *connection; xcb_screen_t *screen; xcb_window_t wnd;
 #define NULL_WND_HANDLE xcb_window_t(0)
 
+#else
+
+#error "Unknown platform"
+
 #endif
 
 #include <map>