Feel free to open an issue on
  https://github.com/ocaml/ocamlbuild/issues
so that we can track the problem down.

On Sat, Jun 25, 2016 at 11:57 AM, Soegtrop, Michael <
michael.soegtrop@intel.com> wrote:

> Dear Gabriel,
>
>
>
> >Did you correctly run
>
> >
> >  eval $(opam config en)
>
> I tried both (in a fresh shell). The effect is the same.
>
>
>
> A question for my understanding: I assumed that for building something
> inside of opam this is not required. I thought I need to do this only when
> I use ocaml to build something outside of opam. This also matches my (very
> limited) experience with opam.
>
>
>
> I try to find out what is going wrong here.
>
>
>
> Best regards,
>
>
>
> Michael
>
>
>
> *From:* Gabriel Scherer [mailto:gabriel.scherer@gmail.com]
> *Sent:* Saturday, June 25, 2016 5:37 PM
> *To:* Soegtrop, Michael <michael.soegtrop@intel.com>
> *Cc:* caml-list@inria.fr
> *Subject:* Re: [Caml-list] Building ocamlbuild with opam fails after opam
> switch <version>
>
>
>
> This is a bug, but I think it is likely to be coming from a
> misconfiguration on your end: the preinstalled test checks
>   $(ocamlc -where)/ocamlbuild
> and if you are in a non-system switch this should not be
> /usr/local/lib/ocaml.
>
> Did you correctly run
>
>
>   eval $(opam config en)
>
> after switching?
>
>
>
> On Sat, Jun 25, 2016 at 9:57 AM, Soegtrop, Michael <
> michael.soegtrop@intel.com> wrote:
>
> Dear OCaml Users,
>
>
>
> Opam works fine for me with the system installed OCaml, but after an opam
> switch I cannot build ocamlbuild or any package depending on it any more.
>
>
>
> Building ocamlbuild fails because it explicitly checks if there is already
> a system installed ocamlbuild:
>
>
>
> # ERROR: Preinstalled ocamlbuild detected at
> /usr/local/lib/ocaml/ocamlbuild
>
> # Installation aborted; if you want to bypass this safety check, pass
> CHECK_IF_PREINSTALLED=false to make
>
> # make: *** [Makefile:333: check-if-preinstalled] Error 2
>
>
>
> Of cause I can just follow this advice and remove this check, but I wonder
> how others handle this.
>
>
>
> Best regards,
>
>
>
> Michael
>
>
>
> Intel Deutschland GmbH
> Registered Address: Am Campeon 10-12, 85579 Neubiberg, Germany
> Tel: +49 89 99 8853-0, www.intel.de
> Managing Directors: Christin Eisenschmid, Christian Lamprechter
> Chairperson of the Supervisory Board: Nicole Lau
> Registered Office: Munich
> Commercial Register: Amtsgericht Muenchen HRB 186928
>
>
>
> Intel Deutschland GmbH
> Registered Address: Am Campeon 10-12, 85579 Neubiberg, Germany
> Tel: +49 89 99 8853-0, www.intel.de
> Managing Directors: Christin Eisenschmid, Christian Lamprechter
> Chairperson of the Supervisory Board: Nicole Lau
> Registered Office: Munich
> Commercial Register: Amtsgericht Muenchen HRB 186928
>