$OpenBSD: patch-Makefile,v 1.3 2012/08/18 22:47:00 avsm Exp $
--- Makefile.orig	Sun Aug  5 16:03:59 2012
+++ Makefile	Sun Aug  5 16:04:44 2012
@@ -1,26 +1,26 @@
 #### Standard configuration parameters
 # Compile using ocamlopt, to use ocamlc set TARGET=byte
-TARGET=opt
+TARGET?=opt
 # Install prefix
-PREFIX=/usr/local
+PREFIX?=/usr/local
 # Library directory of hevea
-LIBDIR=$(PREFIX)/lib/hevea
+LIBDIR?=$(PREFIX)/lib/hevea
 # Where to install programms
-BINDIR=$(PREFIX)/bin
+BINDIR?=$(PREFIX)/bin
 # Install prefix prefix
-DESTDIR=
+DESTDIR?=
 #Where to install hevea.sty
-LATEXLIBDIR=$(PREFIX)/lib/hevea
+LATEXLIBDIR?=$(PREFIX)/lib/hevea
 ##### Advanced configuration parameters
-SUF=
-DIR=
-OCAMLC=$(DIR)ocamlc$(SUF)
-OCAMLFLAGS=
-OCAMLFLAGS=-w ZY
-OCAMLCI=$(OCAMLC)
-OCAMLOPT=$(DIR)ocamlopt$(SUF)
-OCAMLLEX=$(DIR)ocamllex$(SUF) -q
-OCBFLAGS=-j 4 -classic-display
+SUF?=
+DIR?=
+OCAMLC?=$(DIR)ocamlc$(SUF)
+OCAMLFLAGS?=
+OCAMLFLAGS?=-w ZY
+OCAMLCI?=$(OCAMLC)
+OCAMLOPT?=$(DIR)ocamlopt$(SUF)
+OCAMLLEX?=$(DIR)ocamllex$(SUF) -q
+OCBFLAGS?=-j 4 -classic-display
 
 #### End of configuration parameters
 #### The Makefile uses ocamlbuild if present.