File permissions on git fetched packages.

[Mathieu Othacehe]

Hi Guix,

I'm trying to package a specific version of libgit2, fetched from a git
repo. I noticed that when cloned in /gnu/store/xxx-git-checkout, all
files have 444 permissions, because /gnu/store is mounted read-only I guess.

The problem is when /gnu/store/xxx-git-checkout/tests/resources/ are
copied to /tmp and tests are run, they fail when trying to write on read
only files.

Any idea on how to overcome this issue and preserve file permissions on
git fetched packages ?

Thanks,

Mathieu