commit 5ad1e94482756d991e578aabb96d180e108564e7
Author: David Scott <dave.scott@eu.citrix.com>
Date:   Wed May 29 10:12:24 2013 +0000

    When ocaml is installed in an unusual location, help cc find the headers
    
    The problem is triggered by using an OCaml compiler installed from OPAM
    where <caml/mlvalues.h> needs to be looked up relative to something like
    
      $HOME/.opam/4.00.1/lib/ocaml

diff --git a/Makefile b/Makefile
index e2a0e14..b6d05c8 100644
--- a/Makefile
+++ b/Makefile
@@ -32,7 +32,7 @@ OCAMLC += $(OCAMLBFLAGS)
 OCAMLOPT += $(OCAMLOFLAGS)
 OCAMLDEP += $(OCAMLDEPFLAGS)
 
-CFLAGS ?= -fPIC
+CFLAGS ?= -fPIC -I$(OCAMLLIBDIR)
 CLIBS = rt pthread
 # pthread seems necessary with some build of ocaml
 
