- how to clean up sysroot nicely without having to rebuild the cross-compiler?
  for now only removing and stowing a copy somewhere before building stage1
  helps.
- pacman with a '--no-execute-hooks' option
- makepkg with an 'alternate root' option (which doens't collide with
  pacman's options), avoids patching -r and --config into makepkg for
  stage1
- shims and provides and depends don't work yet:
  - binutils and glibc-shim
  - same for gcc-libs: glibc and gcc-libs for gcc
- bsdtar: /home/cross/i486-root/packages/i486/linux-docs-4.15.1-2-i486.pkg.tar.xz: Not found in archive
  bsdtar: /home/cross/i486-root/packages/i486/linux-headers-4.15.1-2-i486.pkg.tar.xz: Not found in archive
  bsdtar: Error exit delayed from previous errors.
  Built package linux.
- currently gcc has a PKGBUILD modified by hand instead of diff seds in DESCR
  (the diff is very big and complex)
- removing all pacman databases and recreating them with repo-add, also
  removing all installed pacman packages seem a little bit paranoic. Find
  out how to speed this up and do it properly.
- as soon as asp32 creates a combined PKGBUILD when exporting a package,
  we can remove the git repo packages32 and the cat of the diff-PKGBUILD
  in build_stage1_package.sh
- when uninstalling pacman in the chroot, you must rename pacman.pacsave
  back to pacman.conf as it is used for building packages
- pacman has some issues with the sync databases (pacman -Syyu results
  in):
  debug: returning error 6 from _alpm_db_register_sync : wrong or NULL argument passed
  error: could not register 'temp' database (wrong or NULL argument passed)
  error: no usable package repositories configured.
  installing and listing packages by hand works without problems.
  debug: unregistering database 'local'
- pacman problem: ca-certificates-utils-shim-20170307-1-any definityely contains
  the /etc/ssl/certs/ and the ca-certificates.crt, but it doens't get installed?!
- make: recursive tarkets like all-recursive don't work, neither with cross-compiled
  make nor with the recompiled make on the stage1 system.
  => rebuilding bash on the target works, but it's a workaround:
  https://unix.stackexchange.com/questions/389022/make-unable-to-recurse-for-autoconf-like-projects/423448#423448
- some packages get build more than once in stage1 (linux-api-headers, pacman-mirrorlist)
- make a wrapper for sed in DESCR, which is actually able to detect whether
  the patch was successful or not. Avoid hard to detect errors, when the
  upstream PKGBUILD(s) change.
- gdb uses cross-compiler source files for debugging:
  Temporary breakpoint 1, 0x004005b0 in main ()
  (gdb) list
  1       /home/cross/.build/i486-unknown-linux-gnu/src/gcc/libgcc/libgcc2.c: No such file or directory.
- stage1
  - stage1: cdrom installs keyrings without having a gpg binary
  - 32 MB is not enough when installing packages => add a swap as first action!
  - stage1 has no bootloader package (syslinux) to install
  - do we really want to install stage1 via a CDROM?
- using the cross compiler for syslinux is most likely overkill