Following legacy packing conventions, `isArm` was defined just for
32-bit ARM instruction set. This is confusing to non packagers though,
because Aarch64 is an ARM instruction set.
The official ARM overview for ARMv8[1] is surprisingly not confusing,
given the overall state of affairs for ARM naming conventions, and
offers us a solution. It divides the nomenclature into three levels:
```
ISA: ARMv8 {-A, -R, -M}
/ \
Mode: Aarch32 Aarch64
| / \
Encoding: A64 A32 T32
```
At the top is the overall v8 instruction set archicture. Second are the
two modes, defined by bitwidth but differing in other semantics too, and
buttom are the encodings, (hopefully?) isomorphic if they encode the
same mode.
The 32 bit encodings are mostly backwards compatible with previous
non-Thumb and Thumb encodings, and if so we can pun the mode names to
instead mean "sets of compatable or isomorphic encodings", and then
voilà we have nice names for 32-bit and 64-bit arm instruction sets
which do not use the word ARM so as to not confused either laymen or
experienced ARM packages.
[1]: https://developer.arm.com/products/architecture/a-profile
(cherry picked from commit ba52ae5048)
Following legacy packing conventions, `isArm` was defined just for
32-bit ARM instruction set. This is confusing to non packagers though,
because Aarch64 is an ARM instruction set.
The official ARM overview for ARMv8[1] is surprisingly not confusing,
given the overall state of affairs for ARM naming conventions, and
offers us a solution. It divides the nomenclature into three levels:
```
ISA: ARMv8 {-A, -R, -M}
/ \
Mode: Aarch32 Aarch64
| / \
Encoding: A64 A32 T32
```
At the top is the overall v8 instruction set archicture. Second are the
two modes, defined by bitwidth but differing in other semantics too, and
buttom are the encodings, (hopefully?) isomorphic if they encode the
same mode.
The 32 bit encodings are mostly backwards compatible with previous
non-Thumb and Thumb encodings, and if so we can pun the mode names to
instead mean "sets of compatable or isomorphic encodings", and then
voilà we have nice names for 32-bit and 64-bit arm instruction sets
which do not use the word ARM so as to not confused either laymen or
experienced ARM packages.
[1]: https://developer.arm.com/products/architecture/a-profile
- `localSystem` is added, it strictly supercedes system
- `crossSystem`'s description mentions `localSystem` (and vice versa).
- No more weird special casing I don't even understand
TEMP
Since at least d7bddc27b2, we've had a
situation where one should depend on:
- `stdenv.cc.bintools`: for executables at build time
- `libbfd` or `libiberty`: for those libraries
- `targetPackages.cc.bintools`: for exectuables at *run* time
- `binutils`: only for specifically GNU Binutils's executables,
regardless of the host platform, at run time.
and that commit cleaned up this usage to reflect that. This PR flips the
switch so that:
- `binutils` is indeed unconditionally GNU Binutils
- `binutils-raw`, which previously served that role, is gone.
so that the correct usage will be enforced going forward and everything
is simple.
N.B. In a few cases `binutils-unwrapped` (which before and now was
unconditionally actual GNU binutils), rather than `binutils` was used to
replace old `binutils-raw` as it is friendly towards some cross
compilation usage by avoiding a reference to the next bootstrapping
change.
First, we need check against the host platform, not the build platform.
That's simple enough.
Second, we move away from exahustive finite case analysis (i.e.
exhaustively listing all platforms the package builds on). That only
work in a closed-world setting, where we know all platforms we might
build one. But with cross compilation, we may be building for arbitrary
platforms, So we need fancier filters. This is the closed world to open
world change.
The solution is instead of having a list of systems (strings in the form
"foo-bar"), we have a list of of systems or "patterns", i.e. attributes
that partially match the output of the parsers in `lib.systems.parse`.
The "check meta" logic treats the systems strings as an exact whitelist
just as before, but treats the patterns as a fuzzy whitelist,
intersecting the actual `hostPlatform` with the pattern and then
checking for equality. (This is done using `matchAttrs`).
The default convenience lists for `meta.platforms` are now changed to be
lists of patterns (usually a single pattern) in
`lib/systems/for-meta.nix` for maximum flexibility under this new
system.
Fixes#30902
Resolved the following conflicts (by carefully applying patches from the both
branches since the fork point):
pkgs/development/libraries/epoxy/default.nix
pkgs/development/libraries/gtk+/3.x.nix
pkgs/development/python-modules/asgiref/default.nix
pkgs/development/python-modules/daphne/default.nix
pkgs/os-specific/linux/systemd/default.nix
We go out of our way (see top of file) to build a single binary
with symlinks for all of the tools, but were losing them
when preparing the bootstrap tools.
For the cc of the intermediate stages, to be precise. Doing the same for
bintools requires lots of refactoring.
This is mainly for the future extensibility as now you can change
documentation generation with impunity without rebuilding the
whole of stdenv.
Existing "mips64el" should be "mipsel".
This is just the barest minimum so that nixpkgs can recognize them as
systems - although required for building individual derivations onto
MIPS boards, it is not sufficient if you want to actually build nixos on
those targets
Aarch64 tools tested briefly with qemu-aarch64,
but neither have been actually used yet :).
For now only "host" indirectly via binary cache
at cache.allvm.org.
This is a temporary workaround to make `nix-env -qa` and `nix search` ignore
broken packages as they they did before this patchset.
This patch should be reverted after `nix` gets a proper fix for this.
See NixOS/nix#1771.
This option makes `meta.evaluate` into a close approximation of the result of
evaluating `.outPath` by checking all the dependencies recursively at a cost of
2x slowdown. Note that actually evaluating `.outPath` costs some
5x-7x more because `.outPath` also computes all the hashes.
I hope this will be a temporary measure. If there is consensus around
issue #33599, then we can follow an explicit `dontCheck`, but default to
not checking during cross builds when none is given.
This pushes check-meta evaluation to derivation evaluation step, leaving all other
attributes accessible.
Before this commit:
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
as expected
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.name --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.meta.description --argstr system aarch64-linux
> Package ‘xen-4.5.5’ in pkgs/applications/virtualization/xen/generic.nix:226 is not supported on ‘aarch64-linux’, refusing to evaluate.
which is unfortunate since its impossible to use packages in autogenerated
documentation on all platforms.
After this commit:
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen --argstr system aarch64-linux
still fails
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.name --argstr system aarch64-linux
> "xen-4.5.5"
> $ HOME=/homeless-shelter NIX_PATH=nixpkgs=$(pwd) nix-instantiate --eval --strict ./default.nix -A xen.meta.description --argstr system aarch64-linux
> "Xen hypervisor and related components (vanilla)"
- All deps go on the PATH
- CC and Bintools wrappers with their host != depender's host still get their
setup hooks run.
- Environment hooks get applied to all packages
This isn't so elegent, but eases the transition on a very significant
PR.
We now have the information to properly determine the role the
cc-wrapper dependency has, by taking advantage of `offset`. No longer
use the soon-to-be-deprecated crossConfig environment variable, the
temp hack used before this change.
4 far-reaching changes: Smaller PATH, New vars, different propagation
logic, and different hook logic
Smaller PATH
------------
`buildInputs` no longer go on the PATH at build time, as they cannot be
run when cross compiling and we don't want to special case. Simply make
a `nativeBuildInput` too if one needs them on the PATH. Fixes#21191.
Many new depedendency variables
-------------------------------
See the stdenv chapter of the nixpkgs manual. I pulled out the existing
documentation of dependency specification into a new section, and added
language for these two (and their propagated equivalents) along side
the others'.
More complex propagation logic
------------------------------
Before a propagated*XXX*Input always acted as if it was specified
directly as a *XXX*Input downstream. That's simple enough, but violates
the intended roles of each sort of dep, which has functional and not
just stylistic consequences.
The new algorithm is detailed in the manual, and ensures everything
ends up in the right place. I tried to give both an informal and formal
description, but I suspect in practice it will not make much sense
until one tries cross compiling, after which it will immediately make
sense as the only sane option.
Simplified hook logic
---------------------
Rather than `envHook` and `crossEnvHook`, whose behavior differs
depending on whether we are cross compiling or not, there is now one
hook per sort (or rather non-propagated and propagated pair of sorts)
of dependency. These new hooks have the same meaning regardless of
cross compilation. See the setup hook section of stdenv chapter of the
Nixpkgs manual for more details.
stdenvNoCC should not inject any C++ standard library, just as it
doesn't inject any C standard library. stdenv still does, but only
indirectly through stdenv.cc. Wrapped clangs can be simplified now that
they don't need to worry about clobbering CoreFoundation when replacing
the C++ standard library implementation.
This generally-good cleanup should assist with debugging some C++
failures in #26805.
- tracing seems annoying enough
- we get errors for all packages instead of aborting on the first one
- easier to differentiate from unwanted packages (broken, unfree, etc.)
This continues #23374, which always kept around both attributes, by
always including both propagated files: `propgated-native-build-inputs`
and `propagated-build-inputs`. `nativePkgs` and `crossPkgs` are still
defined as before, however, so this change should only barely
observable.
This is an incremental step to fully keeping the dependencies separate
in all cases.
I find the separation of concerns, accumulating, then processing, easier
to follow. Also, with my yet-to-be-merged cross work, the accumulation
part will become more complex.
One should do this when needed executables at run time. It is more
honest and cross-friendly than refering to binutils directly, if one
neeeds the default binary tools for the target platform, rather than
binutils in particular.
This requires some small changes in the stdenv, then working around the
weird choice LLVM made to hardcode @rpath in its install name, and then
lets us remove a ton of annoying workaround hacks in many of our Go
packages. With any luck this will mean less hackery going forward.
cc-wrapper may wrap a cc-compiler, but it doesn't need one to build
itself. (c.f. expand-response-params is a separate derivation.) This
helps avoid cycles on the cross stuff, in addition to removing a
useless dependency edge.
I could have been super careful with overrides in the stdenv to avoid
the mass rebuild, but I don't think it's worth it.
Why 6? It seems a decently high number, giving us room for more degrees
of debugging before the `set -x` sledgehammer without incurring a
mass-rebuild.
By default, all previous overrides are discarded as before, as they
would only apply to the old host platform. But sometimes it is useful to
add some new ones, and this optional parameter allows that.
This is needed when cross-compiling for iOS (Aarch64 + Darwin). I also
changed the syntax of the Linux stdenv for visual consistency, though
that has no effect on semantics as the os is already guaranteed to be
Linux.
