$OpenBSD: patch-Makefile,v 1.5 2013/07/17 23:20:46 jturner Exp $
--- Makefile.orig	Wed Jul 17 19:16:02 2013
+++ Makefile	Wed Jul 17 19:16:22 2013
@@ -33,8 +33,8 @@ LVER=lua5.1
 # NOTE: We use "-std=gnu++0x" so we can use "unordered_map", which is in the STL.
 #
 #
-CPPFLAGS+=-std=gnu++0x -g -Wall -Werror $(shell pkg-config --cflags ${LVER}) $(shell pcre-config --cflags)
-LDLIBS+=$(shell pkg-config --libs ${LVER}) -lcurses -lmimetic -lpcre -lpcrecpp
+CPPFLAGS?=-std=gnu++0x -g -Wall -Werror $(shell pkg-config --cflags ${LVER}) $(shell pcre-config --cflags)
+LDLIBS?=$(shell pkg-config --libs ${LVER}) -lcurses -lmimetic -lpcre -lpcrecpp
 
 
 #
