Re: [PATCH v2 0/7] setup: enforce repo passed to `create_repository()` has no state

> 3:  3a7c197f1b = 3:  8dd89f144a builtin/init: refactor messy creation of leading directories
> 4:  c3ced666bd = 4:  f37db1b17d builtin/init: move handling of "core.sharedRepository" into "setup.c"
> 5:  25918a4ff6 = 5:  db76d32f2c builtin/clone: don't apply "core.sharedRepository" to leading dirs
> 6:  a742852675 ! 6:  19388a188c repository: adapt `repo_clear()` to fully reset the repository
>      @@ Commit message
>           some state because we don't make sure to clear the whole structure.
>       
>           Refactor the function to set the whole repository to all-zeroes to avoid
>      -    any kind of leaking state. While at it, make it a bit more robust when
>      -    called on an already-blank repository.
>      +    any kind of leaking state. Replace calls of `FREE_AND_NULL()` to instead
>      +    use free(3p) to avoid zeroing out the data twice.
>