On Wed, Sep 23, 2015 at 10:38:31AM +0200, Gabriel Scherer wrote:
> Thanks for the reproducible information. I just tried and could
> reproduce the issue.
> 
> The problem comes from the fact that, with the command-line invocation
> you use oasis generates the build description files (_tags,
> myocamlbuild.ml, setup.data) in the build directory, not in the source
> directory, but ocamlbuild when invoked (from the source directory)
> will look for them in the source directory. In particular, I could
> "fix" the build by doing

Indeed, the goal is to not contaminate the source directory *at all*.

>   ...
>   ocaml setup.ml -C $PWD/../oasis-camlp4 -configure
>   for f in {myocamlbuild.ml,_tags,setup.data}; do ln -s $PWD/$f
> ../oasis-camlp4; done
>   ocaml setup.ml -C $PWD/../oasis-camlp4 -build -build-dir $PWD/build
> 
> It looks like oasis's behavior with "-C $DIR -configure" is
> problematic: it should generate its files in $DIR -- except maybe
> setup.ml, or then people would have to run (ocaml $DIR/setup.ml -C
> $DIR ...).

I've been playing around a bit with the various combinations of where I
run `ocaml <path>/setup.ml` and `-C`. Since the steps work on "simple"
code, but doesn't on code using `camlp4` I'm leaning towards calling
this a bug.

> TL;DR: this appear to be an oasis issue, rather than a issue with
> CMake or ocamlbuild.

Yes, I'm guessing it's an issue in the code generated by `oasis` and how
it uses `ocamlbuild` and other build tools.

/M

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Magnus Therning                      OpenPGP: 0xAB4DFBA4 
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