diff --git a/Makefile b/Makefile
index 9b7a132..faef8ce 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 CC=gcc
-CFLAGS=-O2 -std=gnu99 -W -Werror -Wall -Wextra -I. 
+CFLAGS=-O2 -std=c99 -W -Werror -Wall -Wextra -I. 
 all:
 	$(CC) $(CFLAGS) main.c i2c.c lis3dh.c -o lis3dh -lm