The final stage asserted
assert prevStage.libiconv == prevStage.darwin.libiconv;
On Darwin `libiconv` is `darwin.libiconv`, so this compares a value with
itself. Nix does not notice: `eqValues` short-circuits only on pointer
identity of the two value slots, and these are two slots that resolve to
one attribute set. It therefore falls through to the derivation case,
which compares `outPath`.
`lib.extendDerivation` guards `outPath` behind the derivation's validity,
which reads `config.allowUnfree`, so the assertion demanded a `config`
option while the package set was still being assembled. When `config` is a
function it is passed `pkgs`, and the loop closes:
(import <nixpkgs> {
system = "aarch64-darwin";
config = { pkgs, lib, ... }: { allowUnfree = lib.isAttrs pkgs; };
}).config.allowUnfree
failed with an infinite recursion on Darwin while evaluating on Linux,
whose stdenv never forces a derivation that early. It now evaluates on
both.
Keep checking the invariant, from `tests.stdenv` instead. By then the
package set is complete, so forcing `outPath` is just a read.
The other twelve assertions in the stage read `passthru` and
`stdenv.cc.cc`, which are ungated, and stay where they are.
Assisted-by: claude-code with claude-opus-5[1m]-high
This optimizes the performance of the hook on machines with multiple cores.
The previous implementation was slow, as it was launching two extra processes per symlink (readlink and ln) while not making use of multiprocessing.
The following improvements were made:
- don't even execute the hook if dontRewriteSymlinks is set
- replace multiple find calls with single find call over all outputs
- use xargs -P to process symlinks in parallel
- add test to check that the hook operates as expected
This improves the implementation of `dumpVars` by removing a call to `install`.
This improves performance when sourcing setup.sh by more than 10%
It should also improve the performance when transitioning between build phases significantly as no process executions are issued anymore,
A test is added, which ensures that no extra execve calls are issued while sourcing setup.sh.
Format all Nix files using the officially approved formatter,
making the CI check introduced in the previous commit succeed:
nix-build ci -A fmt.check
This is the next step of the of the [implementation](https://github.com/NixOS/nixfmt/issues/153)
of the accepted [RFC 166](https://github.com/NixOS/rfcs/pull/166).
This commit will lead to merge conflicts for a number of PRs,
up to an estimated ~1100 (~33%) among the PRs with activity in the past 2
months, but that should be lower than what it would be without the previous
[partial treewide format](https://github.com/NixOS/nixpkgs/pull/322537).
Merge conflicts caused by this commit can now automatically be resolved while rebasing using the
[auto-rebase script](8616af08d9/maintainers/scripts/auto-rebase).
If you run into any problems regarding any of this, please reach out to the
[formatting team](https://nixos.org/community/teams/formatting/) by
pinging @NixOS/nix-formatting.
In preparation for the deprecation of `stdenv.isX`.
These shorthands are not conducive to cross-compilation because they
hide the platforms.
Darwin might get cross-compilation for which the continued usage of `stdenv.isDarwin` will get in the way
One example of why this is bad and especially affects compiler packages
https://www.github.com/NixOS/nixpkgs/pull/343059
There are too many files to go through manually but a treewide should
get users thinking when they see a `hostPlatform.isX` in a place where it
doesn't make sense.
```
fd --type f "\.nix" | xargs sd --fixed-strings "stdenv.is" "stdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "stdenv'.is" "stdenv'.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "clangStdenv.is" "clangStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "gccStdenv.is" "gccStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "stdenvNoCC.is" "stdenvNoCC.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "inherit (stdenv) is" "inherit (stdenv.hostPlatform) is"
fd --type f "\.nix" | xargs sd --fixed-strings "buildStdenv.is" "buildStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "effectiveStdenv.is" "effectiveStdenv.hostPlatform.is"
fd --type f "\.nix" | xargs sd --fixed-strings "originalStdenv.is" "originalStdenv.hostPlatform.is"
```
The previously used pattern was introduced in #318614, but technically
leaked the default flags into the global scope. While this would
probably not make much of a practical difference, making concatTo
support default values is a much cleaner approach.
This fixes using inputDerivation on derivations that are fixed-output.
Previously:
```
nix-repl> drv = runCommand "huh" { outputHash = "sha256-47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU="; outputHashAlgo = "sha256"; outputHashType = "flat"; } "touch $out"
nix-repl> drv.inputDerivation
«derivation /nix/store/d8mjs6cmmvsr1fv7psm6imis5pmh9bcs-huh.drv»
nix-repl> :b drv.inputDerivation
error: fixed output derivation 'huh' is not allowed to refer to other store paths.
You may need to use the 'unsafeDiscardReferences' derivation attribute, see the manual for more details.
```
Fixes: https://github.com/NixOS/nixpkgs/issues/304209
Closes#16182
This improves the error message
Error: _assignFirst found no valid variant!
which occurred when the set of outputs was not sufficient to set
the various outputDev, outputBin, etc variables. Specifically, this
would mean that "out" is not among the outputs, which is valid for
a derivation.
This changes the message to something like
error: _assignFirst: could not find a non-empty variable to assign to outputDev. The following variables were all unset or empty: dev out.
If you did not define an "out" output, make sure to define all the specific required outputs: define an output for one of the unset variables.
While this isn't a full explanation of what stdenv can and can not do,
I think it's vast improvement over the 0 bits of information that it
used to provide. This at least gives a clue as to what's going on, and
even suggests a fix, although probably multiple such fixes are required
in an instance where someone starts with a no-out derivation from scratch
(and decide to persist).
Derivations not using `__structuredAttrs` should not attempt to set
environment variables from `env`.
Derivations using `__structuredAttrs` should fail if `env` is not
exportable.
