Maybe cargo should use git(1) binary instead of libgit2.

Please provide a more detailed description of the problem. In the current form, I cannot reproduce it.

(In reply to Alexey Gladkov from comment #2)
> Please provide a more detailed description of the problem. In the current
> form, I cannot reproduce it.

Step to reproduce:

# make sure that latest Sisyphus rust-cargo is installed:
    $ rpm -q rust-cargo
    rust-cargo-1.57.0-alt1.x86_64

    # clone websocat repo:
    $ git clone https://github.com/vi/websocat
    $ cd websocat

# try to download vendor deps:
    $ cargo vendor
        Updating crates.io index
    error: failed to sync

    Caused by:
      failed to load pkg lockfile

    Caused by:
      failed to get `anymap` as a dependency of package `websocat v1.9.0 (/usr/src/RPM/BUILD/websocat)`

    Caused by:
      failed to fetch `https://github.com/rust-lang/crates.io-index`

    Caused by:
      invalid version 0 on git_proxy_options; class=Invalid (3)

# It failed.

Note: this command works successfully with upstream cargo binary.

It also works with rust-cargo-1.56.1-alt1.

rust-1:1.57.0-alt2 -> sisyphus:

 Thu Dec 09 2021 Alexey Gladkov <legion@altlinux.ru> 1:1.57.0-alt2
 - Don't use system libgit2 for now (ALT#41534).