diff --git a/aprs.cpp b/aprs.cpp
index f44b9ab..66c8923 100644
--- a/aprs.cpp
+++ b/aprs.cpp
@@ -8,7 +8,9 @@
 #include "ublox.h"
 #include "config.h"
 
-
+#if !defined(__OPTIMIZE__)
+#error "APRS Works only when optimization enabled at level at least -O2"
+#endif
 QAPRSBase qaprs;
 
 void aprs_init(){