在 Ubuntu 14.04 上升级 opam

Upgrading opam on Ubuntu 14.04

我正在尝试将我的 opam 升级到最新版本 Ubuntu 14.04

chris@chris-870Z5E-880Z5E-680Z5E:~$ sudo opam update
default    Downloading https://opam.ocaml.org/1.1/urls.txt
Updating ~/.opam/repo/compiler-index ...
Updating ~/.opam/compilers/ ...
Updating ~/.opam/repo/package-index ...
Updating ~/.opam/packages/ ...
The following package has been DELETED:
 - camlp4.4.02.0+2
[WARNING] install and dev-repo are unknown fields in /home/chris/.opam/repo/default/packages/liquidsoap/liquidsoap.1.1.1/opam: is your OPAM up-to-date ?
[WARNING] install is an unknown field in /home/chris/.opam/repo/default/packages/ocurl/ocurl.0.7.2/opam: is your OPAM up-to-date ?
Updating the cache of metadata (~/.opam/state.cache) ...
23 to install | 17 to reinstall | 16 to upgrade | 1 to downgrade | 0 to remove
You can now run 'opam upgrade' to upgrade your system.
chris@chris-870Z5E-880Z5E-680Z5E:~$ sudo opam upgrade
[WARNING] External solver failed with inconsistent return value. Request saved to "/home/chris/.opam/log/solver-error-6572-1.cudf"
Falling back to the internal heuristic.

The dependency ocamlbuild of package variantslib.109.15.03 is not available for your compiler or your OS.
'opam upgrade' failed.

如错误消息所述,variantslib.109.15.03 似乎不适用于我的 OS/compiler 版本。有什么办法可以解决这个问题吗?这是我的编译器版本:

chris@chris-870Z5E-880Z5E-680Z5E:~$ ocaml -version
The OCaml toplevel, version 4.02.0

如果我没记错的话,过去我在使用 opam 1.1 时遇到过一些问题...还有 opam FAQ states that you should move to opam 1.2 (because of : ubuntu bugs]...我个人使用 opam 1.2.2(在 ubuntu 16.04 & 12.04...)

首先,不要使用 sudo,因为 opam 安装在您的用户文件夹中,因此您实际上可能会通过自己锁定它来破坏它。 (我想你已经做到了)。一般来说,如果您不确定自己在做什么,请不要使用 sudo

求解器找不到适合您系统约束的包 variantslib。如果您正在安装或使用某些您认为适用于 Ubuntu 14.04 LTS 的软件包,那么我建议您从干净的状态开始并安装它,而不是执行更新。既然你已经搞砸了 sudo,我实际上建议你删除 ~/.opam 文件夹,然后从

开始
opam init

然后从头开始安装你需要的任何东西。