Out-of-tree testing is broken with the most recent update from
rust-lang/rust because it makes `compiler-builtins` depend on `core` by
path, which isn't usually available. In order to enable testing outside
of rust-lang/rust, add a new crate `builtins-shim` that uses the same
source as `compiler-builtins` but drops the `core` dependency. This has
replaced `compiler-builtins` as the workspace member and entrypoint for
tests.
Create a crate that handles pulling from and pushing to rust-lang/rust.
This can be invoked with the following:
$ cargo run -p josh-sync -- rustc-pull
$ RUSTC_GIT=/path/to/rust/checkout cargo run -p josh-sync -- rustc-push <username>
The published crates fail to build with an edition less than 2024
because they are packaged with `resolver = "3"`, which is a 2024-only
option. Revert back to resolver v2 to drop this requirement.
Fixes: https://github.com/rust-lang/compiler-builtins/issues/883
Update `run.sh` to start testing `libm`. Currently this is somewhat
inefficient because `builtins-test` gets run more than once on some
targets; this can be cleaned up later.
This crate doesn't need to be a default member since it requires the
opposite settings from everything else. Exclude it from the workspace
and run it only when explicitly requested.
This also makes `cargo t --no-default-features` work without additional
qualifiers. `--no-default-features` still needs to be passed to ensure
`#![compiler_builtins]` does not get set.
compiler-builtins needs doctests disabled in order for everything to
work correctly, since this causes an error running rustdoc that is
unrelated to features (our `compiler_builtins` is getting into the crate
graph before that from the sysroot, but `#![compiler_builtins]` is not
set).
We can also remove `test = false` and `doctest = false` in
`builtins-test` since these no longer cause issues. This is unlikely to
be used but it is better to not quietly skip if anything ever gets added
by accident.
The current setup has the `Cargo.toml` for `compiler-builtins` at the
repository root, which means all support crates and other files are
located within the package root. This works for now but is not the
cleanest setup since files that should or shouldn't be included in the
package need to be configured in `Cargo.toml`. If we eventually merge
`libm` development into this repository, it would be nice to make this
separation more straightforward.
Begin cleaning things up by moving the crate source to a new
`compiler-builtins` directory and adding a virtual manifest. For now the
`libm` submodule is also moved, but in the future it can likely move
back to the top level (ideally `compiler-builtins/src` would contain a
symlink to `libm/src/math`, but unfortunately it seems like Cargo does
not like something about the submodule + symlink combination).
Currently there is an interesting situation with the way features get
enabled; `testcrate` enables `mangled-names`, but the `intrinsics.rs`
example requires this feature be disabled (otherwise the test fails with
missing symbols, as expected). This is also the reason that `testcrate`
is not a default workspace member, meaning `cargo test` doesn't actually
run `testcrate`'s tests; making it a default member would mean that
`compiler-builtins/mangled-names` gets enabled when
`examples/intrinsics.rs` gets built, due to the way features get
unified.
Simplify the situation by making moving the example to its own crate as
`builtins-test-intrinsics`. This also means `testcrate` can become a
default member so it is included in `cargo check` or `cargo test` when
run at the workspace root.
`testcrate` and `builtins-test-intrinsics` still can't be built at the
same time since there isn't a straightforward way to have Cargo build
`compiler-builtins` twice with different features. This is a side effect
of us using non-additive features, but there isn't really a better
option since enabling both mangled and unmangled names would render
`builtins-test-intrinsics` useless.
Currently, Cargo.toml specifies Apache-2.0 OR MIT, but LICENSE.txt
describes MIT OR NCSA. compiler-builtins is derived from LLVM's
compiler-rt. LICENSE.txt correctly reflects the state of compiler-rt
prior to relicensing on 2019-01-19, during which time software was
available for use under either MIT or the University of Illinois NCSA
license. After relicensing, however, compiler-rt is available for use
only under Apache-2.0 with the LLVM exception; this is not reflected
anywhere in the repository.
Update the SPDX license identifier to `MIT AND Apache-2.0 WITH
LLVM-exception AND (MIT OR Apache-2.0)`. Each AND portion covers
something specific:
* Apache-2.0 WITH LLVM-exception: this covers work that is derived from
the LLVM repository since after the LLVM relicensing.
* MIT: This covers work that is derived from LLVM before the LLVM
relicensing (under MIT OR NCSA), as well as the vendored `libm`
components.
* MIT AND Apache-2.0: This ensures that any contributions to this
repository, in addition to meeting the above required licenses, is
also released for use under the Rust-standard Apache-2.0 with no LLVM
exception.
See also the parallel license update in rust-lang/libm [1].
Fixes: https://github.com/rust-lang/compiler-builtins/issues/307
Closes: https://github.com/rust-lang/compiler-builtins/pull/511
Link: https://rust-lang.zulipchat.com/#narrow/channel/335408-foundation/topic/Request.20for.20legal.20team.20input.20on.20crate.20licensing
Link: https://github.com/rust-lang/libm/pull/317 [1]
