Re: properties for default version? (was bug#60200: Incompatibilities between gcc-toolchain and R packages)

[Csepp]

Simon Tournier <zimon.toutoune@gmail.com> writes:

> Hi,
>
> As bug#60200 [1], the issue is one that many of us often hit: packages
> with several versions and when the highest one is not the default.
>
> Other said, build systems use some version for compiler and tools but
> Guix can also offer more recent versions for these very same compilers
> and tools.  It leads to the issue when selecting the name of a compiler
> or tool (command line or manifest).  The user does not get the ones used
> as default by build system.
>
> In addition to [1], another example:
>
> $ guix shell ocaml ocaml-ppxlib -- ocaml --version
> The OCaml toplevel, version 5.0.0
>
>
> But the OCaml libraries are built using OCaml compiler v4.14, thus it
> leads to error as:
>
> Error: 
> /gnu/store/vglxlc8riynj1g937clvwv8yg40lln6z-profile/lib/ocaml/site-lib/ppxlib/ppxlib.cmi
>        is not a compiled interface for this version of OCaml.
> It seems to be for an older version of OCaml.
>
> For other cases, such issue is avoided by appending the suffix -next to
> package name; as with ghc-next, python-numpy-next, emacs-next, etc.
>
> Personally, I find the -next trick useful because the package name
> reflects that it is not the default.  However, it can be annoying to
> update manifest files when this -next is becoming default.
>
> Well, what do people think about this Lars’s patch?

As I *just* ran into some OCaml and GCC related issues a few days ago,
I'm in favor of either the default flag or expanding the -next suffix
naming convention to more packages.