diff --git a/Makefile b/Makefile
index 0e91cee..6104d73 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
-CC=gcc
+CC ?= gcc
 
-CFLAGS=-Wall -Wextra -Werror -pedantic -fstack-protector-all -pedantic -std=c99
+CFLAGS+=-Wall -Wextra -pedantic -fstack-protector-all -pedantic -std=c99
 SANITY_FLAGS=-Wfloat-equal -Wshadow -Wpointer-arith
 
 PREFIX ?= /usr