The opam variables `foo` is accessed as %{foo}% in opam metadata, so you
should use

  "PREFIX=%{prefix}%"

On Sat, Jun 25, 2016 at 1:32 PM, Soegtrop, Michael <
michael.soegtrop@intel.com> wrote:

> Dear Gabriel,
>
>
>
> with your pointers I found it.
>
>
>
> I tried two things, one is to switch to a mingw64 4.03.0 compiler package
> I made myself. In this, as it looks, I messed up the transfer of the prefix
> to make (see my compiler file below), which results in the issues with
> building ocamlbuild.
>
>
>
> Then I tried, as a cross check, a switch to the original opam 4.03.0
> package and building ocamlbuild there. This also fails, but cause of a
> different reason (mantis #7268). Somehow I mixed things up in scrolling up
> my shell and thought it was the same bug.
>
>
>
> The .comp file I experimented with is copied below. I didn’t yet find the
> right syntax to combine a string and a variable into one argument
> ("PREFIX="prefix), need to read the opam manual …
>
>
>
> Best regards,
>
>
>
> Michael
>
>
>
> opam-version: "1"
>
> version: "4.03.0"
>
> src: "https://github.com/ocaml/ocaml/archive/4.03.0.tar.gz"
>
> build: [
>
>   [ "git" "clone" "https://github.com/alainfrisch/flexdll.git" ]
>
>   [ "cp" "flexdll/flexdll.h"
> "/usr/x86_64-w64-mingw32/sys-root/mingw/include" ]
>
>   [ "cp" "config/m-nt.h" "config/m.h" ]
>
>   [ "cp" "config/s-nt.h" "config/s.h" ]
>
>   [ "cp" "config/Makefile.mingw64" "config/Makefile" ]
>
>   [ make "-f" "Makefile.nt" "PREFIX="prefix "flexdll" ]
>
>   [ make "-f" "Makefile.nt" "PREFIX="prefix "world" ]
>
>   [ make "-f" "Makefile.nt" "PREFIX="prefix "opt" ]
>
>   [ make "-f" "Makefile.nt" "PREFIX="prefix "opt.opt" ]
>
>   [ make "-f" "Makefile.nt" "PREFIX="prefix "install" ]
>
> ]
>
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