diff --git a/test/fuzz/Makefile b/test/fuzz/Makefile
index 2a9cda99..7a1dab37 100644
--- a/test/fuzz/Makefile
+++ b/test/fuzz/Makefile
@@ -32,7 +32,7 @@
 all compile: lwip_fuzz lwip_fuzz2 lwip_fuzz3
 .PHONY: all clean
 
-CC=afl-gcc
+CC?=afl-gcc
 LDFLAGS=-lm
 # use 'make D=-DUSER_DEFINE' to pass a user define to gcc
 CFLAGS=-O0 $(D)