Rust 1.64.0 added support for workspace inheritance, which allows
for crates to inherit values such as dependency version constraints or
package metadata information from their workspaces [0].
This works by having workspace members specify a value as a table, with
`workspace` set to true. Thus, supporting this in importCargoLock is as
simple as walking the crate's Cargo.toml, replacing inherited values
with their workspace counterpart.
This is also what a forthcoming Cargo release will do for `cargo vendor` [1],
but we can get ahead of it ;)
[0]: https://blog.rust-lang.org/2022/09/22/Rust-1.64.0.html#cargo-improvements-workspace-inheritance-and-multi-target-builds
[1]: https://github.com/rust-lang/cargo/pull/11414
This is useful to teach `importCargoLock` how to download crates from a
registry other than crates.io. Specifically, we publish our own crates
to an internal registry and this feature lets us pull from it seamlessly.
If RUSTFLAGS is set in the environment, Cargo will ignore rustflags
settings in its TOML configuration. So setting RUSTFLAGS=-g (like
separateDebugInfo does) to generate debug info breaks
dynamically-linked Rust packages on musl. This breakage is visible
for any packages that call into C dynamic libraries. If the binary is
linked directly to a C dynamic library, it will fail to build, and if
it depends on a Rust library which links a C dynamic library, it will
segfault at runtime when it tries to call a function from the C
library. I noticed this because pkgsMusl.crosvm is broken for this
reason, since it sets separateDebugInfo = true.
It shouldn't be possible to end up with broken binaries just by using
RUSTFLAGS to do something innocuous like enable debug info, so I think
that, even though we liked the approach of modiyfing .cargo/config
better at the time, it's become clear that it's too brittle, and we
should bite the bullet and patch the compiler instead when targetting
musl. It does not appear to be necessary to modify the compiler at
all when cross-compiling /from/ dynamically-linked Musl to another
target, so I'm only checking whether the target system is
dynamically-linked Musl when deciding whether to make the modification
to the compiler.
This reverts commit c2eaaae50d
("cargoSetupHook: pass host config flags"), and implements the
compiler patching approach instead.
Sometimes it's more ergonomic to set up the build environment in
hooks, to add to the default behaviour rather than replacing it. It's
very surprising that the fetcher works fine with a custom unpackPhase,
but not with custom preUnpack or postUnpack.
Packages that use preUnpack or postUnpack and Cargo FODs seem to be
very rare. I searched Nixpkgs for files containing one of
"cargoHash", "cargoDeps", and "cargoSha256", and one of "preUnpack" or
"postUnpack", and only found two such packages:
python3.pkgs.tokenizers and rustdesk. Neither of their Cargo FOD
hashes are affected by this change. So if that's any indication,
we're unlikely to be breaking many out-of-tree hashes with these
changes either.
Fixes linker errors while building build.rs where it tries to link libiconv but cannot find it.
Rust executable build for Darwin need libiconv, and indeed buildInputs already has this case handled.
So why is another change needed? Suppose we are cross compiling from Darwin (the build platform) to something else, and the package has a build.rs build script.
The build script is built for the build platform (Darwin) and is also a regular Rust executable, needing libiconv, but due to cross compilation (and strict deps) we need an extra nativeBuildInput.
`cargoDeps` is already passed as `mkDerivation` arguments, and should
not be `passthru`ed again. This fixes the mismatch of `drv.cargoDeps`
and the actual dependency when the original derivation is overriden.
unpackFile doesn't dereference symlinks if cargoDeps is a directory, and
some cargo builds run into permission issues because the files the
symlinks point to are not writable.
v1 lock files (generated by default by Cargo versions 1.40 and below)
use a single table, `metadata`, to store the checksums of packages.
The primary motivation for doing this now is that we're considering
vendoring all Cargo lock files in Nixpkgs, some packages still use it
(e.g. cargo-asm), and adding support for it doesn't increase the
complexity of the function. No matter the outcome of the vendoring
discussion, this is a nice thing to have because Cargo still supports v1
lock files.
Used in cases where you need to get the vendor of a target. Such as when
you need to perform dependency resolution outside of Cargo (eg in
Kolloch's crate2nix).
Currently cargo-setup-hook instructs the builder upon cargoSha256 or
cargoHash being out-of-date compared to the Cargo.lock file.
The instructions can be simplified a bit, because nowadays it is fine to
keep a hash empty, instead of filling it with
`0000000000000000000000000000000000000000000000000000`.
Nix nowadays outputs SRI hashes, which should usually be placed in
`cargoHash` instead of `cargoSha256`, but the instructions are still
only referring to `cargoSha256`.
Lastly, the output of Nix doesn't include `got: sha256: ` anymore, as it
now outputs `got: sha256-XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX=`.
It would be nice to make it clear that the trailing `=` is important as
well, so the full example SRI hash is mentioned.
Fixes#204051. I have tried this on the reproducer stated in the ticket.
```
[nix-develop]$ $(nix-build -I nixpkgs=/home/shana/programming/nixpkgs --no-out-link)/tests/foo
running 1 test
test check_module_name ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
```
This change switches to using GCC 11 by default on aarch64-linux, as well as passing `-lgcc` to the linker, per #201485.
See #201254 and #208412 for wider context on the issue.
