quoted

+#define USE_THE_REPOSITORY_VARIABLE

Ah! Seems like `is_bare_repository()` is responsible for this, it would
be nice to not introduce global dependency in a new command, but this
isn't part of your project, so it's okay here.

Yeah, to be honest I was reluctant to use this, and I tried to find if
I could easily drop this dependency. But this is `is_bare_repository`:

int is_bare_repository(void)
{
	/* if core.bare is not 'false', let's see if there is a work tree */
	return is_bare_repository_cfg && !repo_get_work_tree(the_repository);
}

But I couldn't find out what is the dependency of is_bare_repository_cfg
on the_repository yet, but I decided to keep for this RFC.