diff --git a/rbutil/libtools.make b/rbutil/libtools.make
index de70388010..be2a69e2c7 100644
--- a/rbutil/libtools.make
+++ b/rbutil/libtools.make
@@ -27,8 +27,8 @@ APPVERSION ?= $(shell $(TOP)/../tools/version.sh $(TOP)/..)
 CFLAGS += -DVERSION=\""$(APPVERSION)"\"
 TARGET_DIR ?= $(abspath .)/
 
-NATIVECC = gcc
-CC = gcc
+NATIVECC ?= gcc
+CC ?= gcc
 CPPDEFINES=$(shell echo foo | $(CROSS)$(CC) -dM -E -)
 # use POSIX/C99 printf on windows
 CFLAGS += -D__USE_MINGW_ANSI_STDIO=1