[bug#46806] [PATCH] gnu: ocaml-4.07: Bootstrap.

[pukkamustard]

> Thanks! OK to push?

Ok for me!

> Le 1 mars 2021 04:16:14 GMT-05:00, pukkamustard 
> <pukkamustard@posteo.net> a écrit :
> > I managed to build camlboot and ocaml@4.07 with your patches.
> >
> > > Would be fantastic if you could report build time for camlboot
> > > too :).
> >
> > Build time (on a quad-core i7 laptop):
> >
> > ```
> > $ time ./pre-inst-env guix build camlboot --no-offload
> > .
> > .
> > .
> > successfully built
> > /gnu/store/ddi5n28hsrgvb89r8vjs0rfvapxfbaj2-camlboot-0.0.0-0.506280c.drv
> > /gnu/store/79bqayhrc6qfr2k7pfk7fn6lim0f8cfx-camlboot-0.0.0-0.506280c
> >
> > real    322m35.119s
> > user    0m1.523s
> > sys     0m0.140s
> > ```
> >
> > ocaml@4.07 with your patches applied:
> >
> > ```
> > $ time ./pre-inst-env guix build ocaml@4.07 --no-offload
> > successfully built
> > /gnu/store/sdxybpxzjhib5ijn3fx3r29ycp5vvafd-ocaml-4.07.1.drv
> > /gnu/store/cniid9xi3dck7kdpfm77h56h1s0701fm-ocaml-4.07.1
> >
> > real    17m52.923s
> > user    0m9.268s
> > sys     0m1.013s
> > ```
> >
> > ocaml@4.07 at master:
> >
> > ```
> > $ time ./pre-inst-env guix build ocaml@4.07 --no-offload --check
> > successfully built
> > /gnu/store/v599h0bhpyh2rq4nrnqqf56lwbsf0f71-ocaml-4.07.1.drv
> > successfully built
> > /gnu/store/v599h0bhpyh2rq4nrnqqf56lwbsf0f71-ocaml-4.07.1.drv
> > /gnu/store/s7j0vl88zakkdcyvw1jw8cypfzi6ljnd-ocaml-4.07.1
> >
> > real    21m44.000s
> > user    0m14.546s
> > sys     0m1.217s
> > ```
> >
> > > The result should be almost identical to our current 
> > > ocaml-4.07,
> > > though there are some due to different output directory being
> > > embedded.
> >
> > Checked some random files in both ocaml's with diffoscope and 
> > can
> > confirm that differences seem to be mostly different output
> > directories.
> >
> > Haven't run diffoscope on everything as that would take quite 
> > some
> > time...
> >
> > -pukkamustard
> >
> >
> > > > Fantastic! Thank you and thanks to the camlboot project! I 
> > > > will
> > > > try and
> > > > build this tonight.
> > > >
> > > > Julien Lepiller <julien@lepiller.eu> writes:
> > > >
> > > > > Hi Guix!
> > > > >
> > > > > This small series adds camlboot, a project to reimplement a
> > > > > bootstrap
> > > > > for OCaml, which lets us remove the pre-built
> > > > > boot/ocaml{c,lex}
> > > > > :)
> > > > >
> > > > > The first patch builds the bootstraped ocamlc and ocamllex.
> > > > > This
> > > > > takes
> > > > > around 4 hours to build. The second patch rebuilds them 
> > > > > using
> > > > > the source
> > > > > code for ocaml 4.07.1, instead of the modified sources used 
> > > > > in
> > > > > camlboot, and reuse them to run the main Makefile (make
> > > > > world.opt).
> > > > >
> > > > > As a result, we have identical files for this bootstrap and
> > > > > the
> > > > > unbootstrapped OCaml (up to output store paths and hash of
> > > > > some
> > > > > files
> > > > > that get embedded in native files, which differ because of 
> > > > > the
> > > > > different output path).