nixpkgs/nixos/doc/manual/from_md
Adam Joseph c0085404bd lib/systems/inspect.nix: remove isPowerPC
Very confusingly, the `isPowerPC` predicate in
`lib/systems/inspect.nix` does *not* match `powerpc64le`!

This is because `isPowerPC` is defined as

  isPowerPC      = { cpu = cpuTypes.powerpc; };

Where `cpuTypes.powerpc` is:

  { bits = 32; significantByte = bigEndian; family = "power"; };

This means that the `isPowerPC` predicate actually only matches the
subset of machines marketed under this name which happen to be 32-bit
and running in big-endian mode which is equivalent to:

  with stdenv.hostPlatform; isPower && isBigEndian && is32bit

This seems like a sharp edge that people could easily cut themselves
on.  In fact, that has already happened: in
`linux/kernel/common-config.nix` there is a test which will always
fail:

  (stdenv.hostPlatform.isPowerPC && stdenv.hostPlatform.is64bit)

A more subtle case of the strict isPowerPC being used instead of the
moreg general isPower accidentally are the GHC expressions:

  Update pkgs/development/compilers/ghc/8.10.7.nix
  Update pkgs/development/compilers/ghc/8.8.4.nix
  Update pkgs/development/compilers/ghc/9.2.2.nix
  Update pkgs/development/compilers/ghc/9.0.2.nix
  Update pkgs/development/compilers/ghc/head.nix

Since the remaining legitimate use sites of isPowerPC are so few, remove
the isPowerPC predicate completely. The alternative expression above is
noted in the release notes as an alternative.

Co-authored-by: sternenseemann <sternenseemann@systemli.org>
2022-05-25 09:45:42 +02:00
..
administration nixos-container: Use new configuration & state directories 2022-04-27 18:35:08 +12:00
configuration nixos/doc: improve example of renaming network interfaces 2021-11-21 20:12:31 -08:00
development nixos/manual: Clarify execute exit status 2022-04-21 10:54:00 +02:00
installation treewide: chown user:group instead of user.group to fix warnings from coreutils 9.1 2022-05-05 22:05:18 +00:00
release-notes lib/systems/inspect.nix: remove isPowerPC 2022-05-25 09:45:42 +02:00
contributing-to-this-manual.chapter.xml
README.md

This directory is temporarily needed while we transition the manual to CommonMark. It stores the output of the ../md-to-db.sh script that converts CommonMark files back to DocBook.

We are choosing to convert the Markdown to DocBook at authoring time instead of manual building time, because we do not want the pandoc toolchain to become part of the NixOS closure.

Do not edit the DocBook files inside this directory or its subdirectories. Instead, edit the corresponding .md file in the normal manual directories, and run ../md-to-db.sh to update the file here.