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" ]

]