Revert a revert of a merge that shouldn't have been in master but was intentionally in staging.
Next time I'll do this right after the revert instead of so far down the line...
This reverts commit 9adad8612b.
This will break part of the bootstrap tools tests because the new tools
need some changes in the stdenv, but if I change them all at once, the
stdenv breaks with the old bootstrap tools. So I'm doing this first, then
will make changes to the stdenv once this bundle is built and I can use
it.
I also added some functionality to let me test one set of bootstrap tools
on another nixpkgs tree, which makes testing a lot more pleasant.
This reverts commit debd401b0f.
We must not use a single-binary build for the bootstrap since the common
binary gains a dynamic linkage to gmp (due to 'factor' and 'expr'
handling arbitrary-precision arithmetic).
Our coreutils now uses single-binary-build mode where, by default,
simple shebang scripts are used for all the binaries. That doesn't work
e.g. with the Linux unpacker which only handles standard binaries and
symlinks. Let's use the symlinked mode instead for boostrapping.
This does NOT change any stdenv hashes.
I only tested the case most important to me:
$ nix-build pkgs/top-level/release.nix -A stdenvBootstrapTools.x86_64-linux.test
The $lib output refers to the terminfo database in $out, which is about
10x larger than the ncurses shared library. Splitting these outputs
saves a small amount of space for any derivations that use the terminfo
database but not the ncurses library, but we do not have evidence that
any such exist.
This un-hardcodes the bootstrap tools passed into the Darwin stdenv and
thus allows us to quickly iterate on improving the design of the full
bootstrap process. We can easily change the contents of the bootstrap
tools and evaluate an entire bootstrap all the way up to real packages.
