diff --git a/include/wx/osx/private/timer.h b/include/wx/osx/private/timer.h
index 01367d359c..cd990764c3 100644
--- a/include/wx/osx/private/timer.h
+++ b/include/wx/osx/private/timer.h
@@ -1,7 +1,7 @@
 /* common warning snippet for all osx direct includes */
 
 #ifndef wxOSX_USE_CARBON
-#error "this files should only be included after platform.h was included
+#error "this files should only be included after platform.h was included"
 #endif
 
 #if 1 // revert to wxOSX_USE_COCOA_OR_IPHONE in case of problems