syntax error when building ocamlbuild 0.12.0

[ezal]

I'm trying to install ocamlbuild through opam.

I get the following output:

$ opam install ocamlbuild
The following actions will be performed:
  ∗ install ocamlbuild 0.12.0

<><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ocamlbuild.0.12.0] found in cache

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] The compilation of ocamlbuild failed at "/home/eugen/.opam/opam-init/hooks/sandbox.sh build make check-if-preinstalled all opam-install".

#=== ERROR while compiling ocamlbuild.0.12.0 ==================================#
# context     2.0.0~rc3 | linux/x86_64 | base-bigarray.base base-threads.base base-unix.base | https://opam.ocaml.org
# path        ~/.opam/4.06.1/.opam-switch/build/ocamlbuild.0.12.0
# command     ~/.opam/opam-init/hooks/sandbox.sh build make check-if-preinstalled all opam-install
# exit-code   2
# env-file    ~/.opam/log/ocamlbuild-9258-5f1023.env
# output-file ~/.opam/log/ocamlbuild-9258-5f1023.out
### output ###
# [...]
# 4334 additional bytes used for bindings
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/lexers.mli
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/lexers.ml
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/param_tags.mli
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/param_tags.ml
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/command.mli
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/command.ml
# ocamlc -w L -w R -w Z -I src -I +unix -safe-string -bin-annot -c src/ocamlbuild_config.ml
# File "src/ocamlbuild_config.ml", line 10, characters 0-3:
# Error: Syntax error
# Makefile:422: recipe for target 'src/ocamlbuild_config.cmo' failed
# make: *** [src/ocamlbuild_config.cmo] Error 2

The culprit line looks like this: let ocaml_native =

[gasche]

This is very strange -- many people can build ocamlbuild just fine. What is the OCaml version being used to build?

[ezal]

The OCaml version is 4.06.1, but this seems to be related to the opam packaging.

I've just solved this by running: opam config set-global ocaml-native true opam config set-global ocaml-native-tools true

It seems that in opam.2.0.0 these configuration variables are not set. Or at least on my machine they were not set for some reason...

[gasche]

OCamlbuild 0.14.0 is now out, and has been converted to opam2 -- the opam file in trunk has also been updated. Could you maybe try this new version?