Hi Simon,

> Without any specification about the version, if a package name is
> defined at several versions, then the command-line uses the higher
> version of this package.
minor nit-pick: Not the command-line, but everything that uses
specifications. So manifests via SPECIFICATIONS->MANIFEST are also
affected, see:

    (use-modules (gnu packages) (guix profiles))
    (manifest-entries (specifications->manifest '("gcc-toolchain")))
    $2 = (#<<manifest-entry> name: "gcc-toolchain" version: "12.2.0" …)

The -next suffix has the obvious disadvantage that specifications may
become invalid as we move -next to the “regular” package. So maybe
marking packages “default” like the attached patch does could improve
the current situation. Not just for gcc, but also Haskell and Python
come to mind.

Cheers,
Lars