diff --git a/makefile b/makefile
index 685848c..81768a8 100644
--- a/makefile
+++ b/makefile
@@ -5,7 +5,7 @@ TARGET = sw1nek23per
 LFLAGS ?= 
 
 ifeq ($(MODE), debug)
-	CFLAGS = -ggdb -Wall
+	CFLAGS = -ggdb -Wall -O0
 else ifeq ($(MODE), release)
 	CFLAGS = -Wall -O2
 else