'opam install uri' failed

Question

I'm trying to install the uri package for Opam but I keep running in to this error.

==== ERROR [while installing uri.1.3.8] ====
# opam-version    0.9.6 (latest-103-g955b7ca)
# os              linux
# command         ocaml setup.ml -configure --prefix /root/.opam/system
# path            /root/.opam/system/build/uri.1.3.8
# exit-code       1
# env-file        /root/.opam/system/build/uri.1.3.8/uri-ffb3fd.env
# stdout-file     /root/.opam/system/build/uri.1.3.8/uri-ffb3fd.out
# stderr-file     /root/.opam/system/build/uri.1.3.8/uri-ffb3fd.err
### stderr ###
ocamlfind: Package `compiler-libs.toplevel' not found
W: Field 'pkg_compiler_libs_toplevel' is not set: Command ''/root/.opam/system/bin/ocamlfind' query -format %d compiler-libs.toplevel > '/tmp/oasis-85d951.txt'' terminated with error code 2
E: Cannot find findlib package compiler-libs.toplevel
E: Failure("1 configuration error")

'opam install uri' failed.

I'm pretty new to Ocaml and the Opam repo. I really have no idea what is going wrong. I am running Ubuntu 12.04 and have Ocaml 3.12.1 installed.

Thanks for any insight you can provide!

Answer 1

I just installing uri under 3.12.1 without any issues.

3.12.1 is under your system ocaml compiler, right? and you probably installed ocaml via aptitude? In which case you need to also install ocaml-compiler-libs. There are a number of other optional packages for OCaml that are usually needed and may run into in the future --camlp4-extra is another that I see missed and oft needed. A maximal list is here.

I would also upgrade OPAM, since there were some changes to the uri package only two days ago. opam update; opam upgrade. This will require some re-compilation, and make sure you switched to the correct compiler.

Answer 2

The package "compiler-libs.toplevel" is missing. If I remember right, it's shipped together with ocaml and is available only since version 4.0.

Either install an older version of uri or update your compiler to 4.0. For details look here