In Nixpkgs, we assume that the "config" field is a canonicalized GNU
triple. I noticed that non-canonical values were being used here,
because the pkgsCross.mips64el-linux-gnu triples did not contain the
vendor field, but the pkgsCross.mips64el-linux-gnu.pkgsStatic did.
Here, I've run all the MIPS triples in lib.systems.examples through
config.sub to canonicalize them. I think this will avoid nasty
surprises in future.
Tested by building Nix and the bootstrap files for
pkgsCross.mips64el-linux-gnu.
`m` must always be an attrset at this point. It is basically always
evaluated. This will make it throw when any of the attrs is accessed,
rather than just `config`. We assume that this will improve the error
message in more scenarios.
This has been deprecated for a long time, and it's doubtful it had any
users to start with. And having an undisablable warning when
enumarating platforms is not good.
These servers apparently no longer exist, since September 2, 2021[1].
If somebody needs this for non-Scaleway machines, they should suggest
its reintroduction with a different name.
[1]: https://news.ycombinator.com/item?id=27192757
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>
canExecute is like isCompatible, but also checks that the Kernels are
_equal_, i.e. that both platforms use the same syscall interface. This
is crucial in order to actually be able to execute binaries for the
other platform.
isCompatible is dropped, since it has changed semantically and there's
no use case left in nixpkgs.
Since we (exclusively) use isCompatible to gauge whether platform a can
execute binaries built for platform b, mode switching CPUs are not to be
considered compatible for our purposes: Switching the mode of a CPU
usually requires a reset. At the very least we can't execute a mix of
executables for the two modes which would usually be the case in nixpkgs
where we may want to execute buildInputs for the hostPlatform in
addition to nativeBuildInputs for the buildPlatform.
Since the list only gates the platforms the nixpkgs flake exposes
packages to build on, the `hydra` label made little sense. It was also
only used for this purpose, so the `tier*` attributes were largely
unnecessary.
To reflect the intention more accurately, we expose
`lib.systems.flakeExposed` and use it to gate flake.nix's system list.
Currently the only way to set the description for a submodule type is to
use `freeformType`. This is not ideal as it requires setting a
freeform type, and evaluates the submodule config unnecessarily.
Instead, add a `description` argument to `submoduleWith`.
This reverts commit PR #167947.
Flakes aren't standardised and the `lib` namespace shouldn't be
polluted with utilities that serve only experimental uses.
