ld: Error: unable to disambiguate: -shared-libgcc

I'm getting the linker error ld: Error: unable to disambiguate: -shared-libgcc when trying to create a .o file with (modes object).
I'm not sure that the issue is with Dune, but I'm hoping you can shed some light.

To replicate, create a new project with dune init project broken, run opam install class_group_vdf, and finally change bin/dune to:

(executable
 (public_name broken)
 (name main)
 (libraries broken class_group_vdf)
 (modes exe object))

Then, dune build should fail with ld: Error: unable to disambiguate: -shared-libgcc.

Do you have any idea what might be causing this?
It seems odd that a single library would use conflicting versions of another library, so perhaps a flag Dune is passing is introducing the conflict?
I'm also confused as to why an apparently shared library is coming up when doing static linking.

Specifications

dune 3.6.2, ocaml 4.14.1, Ubuntu 22.04.

Additional information

https://gist.github.com/emchristiansen/da7584036fcbe7a3373f8298dbeaf84a

https://github.com/zshipko/rust-ocaml-starter/issues/4

Reproduce the failure in a project created with dune init project broken, after installing class_group_vdf and changing bin/dune to use (modes exe object). Start by examining the build or linker command associated with dune build and the reported -shared-libgcc error on Ubuntu 22.04. Done means identifying whether Dune or a dependency introduces the conflicting flag and clarifying the cause.