pulling cmake ExternalProject during guix builds

[Erik Garrison <erik.garrison@gmail.com>]

Hi help-guix,

Apologies for the spam, but I'm new here and not sure if IRC or the mailing
list is a better channel to use for help. In any case, this will be
searchable later.

I'm using cmake's ExternalProject_Add functionality to manage project
dependencies, but this is not usable with guix's build containerization
system. I get "Could not resolve host: ..." when cmake invokes git to try
to clone the repositories.

Can network access be provided to the build container? Or, is there perhaps
another low-effort workaround in guix?

As far as I understand, the only reasonable alternative to add the
dependencies as submodules in the main repo? This will still work with the
ExternalProject_Add pattern, but it adds an extra point of configuration,
and users will need to use a recursive git clone, which is sometimes
confusing.

Thanks in advance for the clarification,

Erik