diff --git a/Makefile b/Makefile
index 293f0317..4a001c9e 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ ALL_LDFLAGS = $(LDFLAGS)
 ALL_LIBS = $(LIBS)
 
 ifeq ($(RELEASE), 1)
-	ALL_CXXFLAGS += -O3
+	ALL_CXXFLAGS += -O3 -DNDEBUG
 	ALL_LDFLAGS += -s
 	FILENAME_DEF = CSE2.exe
 else