riscv32im-risc0-zkvm-elf: add target
This pull request adds RISC Zero's Zero Knowledge Virtual Machine (zkVM) as a target for rust. The zkVM used to produce proofs of execution of RISC-V ELF binaries. In order to do this, the target will execute the ELF to generate a receipt containing the output of the computation along with a cryptographic seal. This receipt can be verified to ensure the integrity of the computation and its result. This target is implemented as software only; it has no hardware implementation.
## Tier 3 target policy:
Here is a copy of the tier 3 target policy:
> Tier 3 target policy:
>
> At this tier, the Rust project provides no official support for a target, so we
> place minimal requirements on the introduction of targets.
>
> A proposed new tier 3 target must be reviewed and approved by a member of the
> compiler team based on these requirements. The reviewer may choose to gauge
> broader compiler team consensus via a [[Major Change Proposal (MCP)](https://forge.rust-lang.org/compiler/mcp.html)](https://forge.rust-lang.org/compiler/mcp.html).
>
> A proposed target or target-specific patch that substantially changes code
> shared with other targets (not just target-specific code) must be reviewed and
> approved by the appropriate team for that shared code before acceptance.
>
> - A tier 3 target must have a designated developer or developers (the "target
> maintainers") on record to be CCed when issues arise regarding the target.
> (The mechanism to track and CC such developers may evolve over time.)
The maintainers are named in the target description file
> - Targets must use naming consistent with any existing targets; for instance, a
> target for the same CPU or OS as an existing Rust target should use the same
> name for that CPU or OS. Targets should normally use the same names and
> naming conventions as used elsewhere in the broader ecosystem beyond Rust
> (such as in other toolchains), unless they have a very good reason to
> diverge. Changing the name of a target can be highly disruptive, especially
> once the target reaches a higher tier, so getting the name right is important
> even for a tier 3 target.
> - Target names should not introduce undue confusion or ambiguity unless
> absolutely necessary to maintain ecosystem compatibility. For example, if
> the name of the target makes people extremely likely to form incorrect
> beliefs about what it targets, the name should be changed or augmented to
> disambiguate it.
> - If possible, use only letters, numbers, dashes and underscores for the name.
> Periods (`.`) are known to cause issues in Cargo.
>
We understand.
> - Tier 3 targets may have unusual requirements to build or use, but must not
> create legal issues or impose onerous legal terms for the Rust project or for
> Rust developers or users.
> - The target must not introduce license incompatibilities.
We understand and will not introduce incompatibilities. All of our code that we publish is licensed under Apache-2.0.
> - Anything added to the Rust repository must be under the standard Rust license (`MIT OR Apache-2.0`).
We understand. We are open to either license for the Rust repository.
> - The target must not cause the Rust tools or libraries built for any other
> host (even when supporting cross-compilation to the target) to depend
> on any new dependency less permissive than the Rust licensing policy. This
> applies whether the dependency is a Rust crate that would require adding
> new license exceptions (as specified by the `tidy` tool in the
> rust-lang/rust repository), or whether the dependency is a native library
> or binary. In other words, the introduction of the target must not cause a
> user installing or running a version of Rust or the Rust tools to be
> subject to any new license requirements.
We understand. The runtime libraries and the execution environment and software associated with this environment uses `Apache-2.0` so this should not be an issue.
> - Compiling, linking, and emitting functional binaries, libraries, or other
> code for the target (whether hosted on the target itself or cross-compiling
> from another target) must not depend on proprietary (non-FOSS) libraries.
> Host tools built for the target itself may depend on the ordinary runtime
> libraries supplied by the platform and commonly used by other applications
> built for the target, but those libraries must not be required for code
> generation for the target; cross-compilation to the target must not require
> such libraries at all. For instance, `rustc` built for the target may
> depend on a common proprietary C runtime library or console output library,
> but must not depend on a proprietary code generation library or code
> optimization library. Rust's license permits such combinations, but the
> Rust project has no interest in maintaining such combinations within the
> scope of Rust itself, even at tier 3.
We understand. We only depend on FOSS libraries. Dependencies such as runtime libraries for this target are licensed as `Apache-2.0`.
> - "onerous" here is an intentionally subjective term. At a minimum, "onerous"
> legal/licensing terms include but are *not* limited to: non-disclosure
> requirements, non-compete requirements, contributor license agreements
> (CLAs) or equivalent, "non-commercial"/"research-only"/etc terms,
> requirements conditional on the employer or employment of any particular
> Rust developers, revocable terms, any requirements that create liability
> for the Rust project or its developers or users, or any requirements that
> adversely affect the livelihood or prospects of the Rust project or its
> developers or users.
There are no such terms present
> - Neither this policy nor any decisions made regarding targets shall create any
> binding agreement or estoppel by any party. If any member of an approving
> Rust team serves as one of the maintainers of a target, or has any legal or
> employment requirement (explicit or implicit) that might affect their
> decisions regarding a target, they must recuse themselves from any approval
> decisions regarding the target's tier status, though they may otherwise
> participate in discussions.
I am not the reviewer of this pull request
> - This requirement does not prevent part or all of this policy from being
> cited in an explicit contract or work agreement (e.g. to implement or
> maintain support for a target). This requirement exists to ensure that a
> developer or team responsible for reviewing and approving a target does not
> face any legal threats or obligations that would prevent them from freely
> exercising their judgment in such approval, even if such judgment involves
> subjective matters or goes beyond the letter of these requirements.
We understand.
> - Tier 3 targets should attempt to implement as much of the standard libraries
> as possible and appropriate (`core` for most targets, `alloc` for targets
> that can support dynamic memory allocation, `std` for targets with an
> operating system or equivalent layer of system-provided functionality), but
> may leave some code unimplemented (either unavailable or stubbed out as
> appropriate), whether because the target makes it impossible to implement or
> challenging to implement. The authors of pull requests are not obligated to
> avoid calling any portions of the standard library on the basis of a tier 3
> target not implementing those portions.
The target implements core and alloc. And std support is currently experimental as some functionalities in std are either a) not applicable to our target or b) more work in research and experimentation needs to be done. For more information about the characteristics of this target, please refer to the target description file.
> - The target must provide documentation for the Rust community explaining how
> to build for the target, using cross-compilation if possible. If the target
> supports running binaries, or running tests (even if they do not pass), the
> documentation must explain how to run such binaries or tests for the target,
> using emulation if possible or dedicated hardware if necessary.
See file target description file
> - Tier 3 targets must not impose burden on the authors of pull requests, or
> other developers in the community, to maintain the target. In particular,
> do not post comments (automated or manual) on a PR that derail or suggest a
> block on the PR based on a tier 3 target. Do not send automated messages or
> notifications (via any medium, including via ``@`)` to a PR author or others
> involved with a PR regarding a tier 3 target, unless they have opted into
> such messages.
We understand.
> - Backlinks such as those generated by the issue/PR tracker when linking to
> an issue or PR are not considered a violation of this policy, within
> reason. However, such messages (even on a separate repository) must not
> generate notifications to anyone involved with a PR who has not requested
> such notifications.
We understand.
> - Patches adding or updating tier 3 targets must not break any existing tier 2
> or tier 1 target, and must not knowingly break another tier 3 target without
> approval of either the compiler team or the maintainers of the other tier 3
> target.
> - In particular, this may come up when working on closely related targets,
> such as variations of the same architecture with different features. Avoid
> introducing unconditional uses of features that another variation of the
> target may not have; use conditional compilation or runtime detection, as
> appropriate, to let each target run code supported by that target.
We understand.
> If a tier 3 target stops meeting these requirements, or the target maintainers
> no longer have interest or time, or the target shows no signs of activity and
> has not built for some time, or removing the target would improve the quality
> of the Rust codebase, we may post a PR to remove it; any such PR will be CCed
> to the target maintainers (and potentially other people who have previously
> worked on the target), to check potential interest in improving the situation.
We understand.
This also adds changes in the rust test suite in order to get a few of them to
pass.
Co-authored-by: Frank Laub <flaub@risc0.com>
Co-authored-by: Urgau <3616612+Urgau@users.noreply.github.com>
bootstrap: handle vendored sources when remapping crate paths
#115872 introduced a feature to add path remapping for crate dependencies, but only when they came from Cargo's registry cache, not a vendor directory.
This caused builds that used remapped debuginfo and vendor directories to fail with:
```
std::fs::read_dir(registry_src) failed with No such file or directory (os error 2)
```
or (if the `registry/src` directory exists but is empty)
```
error: --remap-path-prefix must contain '=' between FROM and TO
```
Fixes#117885 by explicitly supporting the `vendor` directory and adding it to `RUSTC_CARGO_REGISTRY_SRC_TO_REMAP`.
Note that `bootstrap.py` already assumes that `./vendor` within the rust repo is the only supported vendoring location.
r? `@pietroalbini`
By "actual" we refer to the uplifting logic where we may not compile the requested stage;
instead, we uplift it from the previous stages. Which can lead to bootstrap failures in
specific situations where we request stage X from other steps. However we may end up
uplifting it from stage Y, causing the other stage to fail when attempting to link with
stage X which was never actually built.
Signed-off-by: onur-ozkan <work@onurozkan.dev>
bump bootstrap dependencies
This PR removes hard-coded patch versions, updates bootstrap's dependency stack to recent versions (some of the versions were released 3-4 years ago), and removes a few dependencies from bootstrap.
Removed dependencies:

This option is largely there to help people to manage the memory usage
on their systems during the LLVM build. The linking phase is as usual
are the heaviest part of the build and if in an unlucky conincidence the
circumstances align to kick off N_CORES links at the same time, not even
hundreds of GiB of memory may suffice. It makes a lot of sense for
developers to set&forget this option unconditionally.
Not to mention, this option does not, in any way, affect the generated
code (at least as far as I know.) It really doesn’t matter what
option the CI build LLVM used here and/or if it matches with the user’s
configuration.
Finally, 0 actual link jobs implied by `download-ci-llvm` is guaranteed
to stay within the limits that are reasonable to set with this option.
mir-opt and custom target fixes
From https://github.com/rust-lang/rust/issues/115642#issuecomment-1879589022
> > Could you please test the last two commits from https://github.com/onur-ozkan/rust/commits/panic-abort-mir-opt when you have the time? The first commit should resolve the error of using the nightly flag with a stable compiler, and the second one should resolve the custom target issue.
> I tested with the two commits and the errors of using nightly flag and custom target specs were not seen.
Testing was completed for the test suites like ui, run-pass-valgrind, coverage, mir-opt, codegen, assembly, incremental.
Fixes#115642
in particular, this makes the `c` feature for compiler-builtins an explicit opt-in, rather than silently detected by whether `llvm-project` is checked out on disk.
exposing this is necessary because the `cc` crate doesn't support cross-compiling to MSVC, and we want people to be able to run `x check --target foo` regardless of whether they have a c toolchain available.
this also uses the new option in CI, where we *do* want to optimize compiler_builtins.
the new option is off by default for the `dev` channel and on otherwise.
Use the current target instead of iterating over all targets
Since we already iterate through targets in StepDescription::maybe_run, there is no need to iterate targets again in the install step for std.
Compared the results before and after applying the changes to install step of std, and there were no differences.
```sh
~/devspace/.other/rustc-builds $ sha256sum ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-*
c2ea86fc25ffac87b0b135f31ba9644ad97549da4c050c3921b437d1e18285fd ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-pc-windows-gnu
d2f1081a779962e2cbc27f53191783d13428abd0964465547af78ce34c7251dd ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-unknown-linux-gnu
~/devspace/.other/rustc-builds $ sha256sum ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-*
c2ea86fc25ffac87b0b135f31ba9644ad97549da4c050c3921b437d1e18285fd ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-pc-windows-gnu
d2f1081a779962e2cbc27f53191783d13428abd0964465547af78ce34c7251dd ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-unknown-linux-gnu
```
Fixes#119533
Run Miri and mir-opt tests without a target linker
Normally, we need a linker for the target to build the standard library. That's only because `std` declares crate-type lib and dylib; building the dylib is what creates a need for the linker.
But for mir-opt tests (and for Miri) we do not need to build a `libstd.so`. So with this PR, when we build the standard library for mir-opt tests, instead of `cargo build` we run `cargo rustc --crate-type=lib` which overrides the configured crate types in `std`'s manifest.
I've also swapped in what seems to me a better hack than `BOOTSTRAP_SKIP_TARGET_SANITY` to prevent cross-interpreting with Miri from checking for a target linker and expanded it to mir-opt tests too. Whether it's actually better is up to a reviewer.
bootstrap: Move -Clto= setting from Rustc::run to rustc_cargo
It prevents a full rebuild of stage 1 compiler when issuing "x.py test" with rust.lto != thin-local in config.toml.
Allow coverage tests to ignore test modes, and to enable color in coverage reports
This PR adds two new header directives to compiletest, intended for use by coverage tests (and by #119033 in particular).
The new headers are:
- `// ignore-mode-{mode}` causes a test to not be run in a particular compiletest mode (e.g. `ignore-mode-coverage-run`).
- This can theoretically be used by any test, but coverage tests are currently the only ones that automatically run in multiple modes, so it's not very useful for other kinds of test.
- `// llvm-cov-flags: --use-color` makes `coverage-run` tests pass the flag `--use-color` when generating coverage reports.
- For most tests, non-coloured reports are easier to read and more portable across platforms. But for #119033 specifically, we want to test that `llvm-cov` slices up source text correctly, which only happens when colour output is enabled.
Rollup of 10 pull requests
Successful merges:
- #118521 (Enable address sanitizer for MSVC targets using INFERASANLIBS linker flag)
- #119026 (std::net::bind using -1 for openbsd which in turn sets it to somaxconn.)
- #119195 (Make named_asm_labels lint not trigger on unicode and trigger on format args)
- #119204 (macro_rules: Less hacky heuristic for using `tt` metavariable spans)
- #119362 (Make `derive(Trait)` suggestion more accurate)
- #119397 (Recover parentheses in range patterns)
- #119417 (Uplift some miscellaneous coroutine-specific machinery into `check_closure`)
- #119539 (Fix typos)
- #119540 (Don't synthesize host effect args inside trait object types)
- #119555 (Add codegen test for RVO on MaybeUninit)
r? `@ghost`
`@rustbot` modify labels: rollup
Since we already iterate through targets in StepDescription::maybe_run, there is no need to
iterate targets again in the install step for std.
Compared the results before and after applying the changes to install step of std, and there were no differences.
```sh
~/devspace/.other/rustc-builds $ sha256sum ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-*
c2ea86fc25ffac87b0b135f31ba9644ad97549da4c050c3921b437d1e18285fd ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-pc-windows-gnu
d2f1081a779962e2cbc27f53191783d13428abd0964465547af78ce34c7251dd ./old/usr/local/lib/rustlib/manifest-rust-std-x86_64-unknown-linux-gnu
~/devspace/.other/rustc-builds $ sha256sum ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-*
c2ea86fc25ffac87b0b135f31ba9644ad97549da4c050c3921b437d1e18285fd ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-pc-windows-gnu
d2f1081a779962e2cbc27f53191783d13428abd0964465547af78ce34c7251dd ./new/usr/local/lib/rustlib/manifest-rust-std-x86_64-unknown-linux-gnu
```
Signed-off-by: onur-ozkan <work@onurozkan.dev>
Remove usage of deprecated `missing-tools` bootstrap flag
This PR removes the usage of `--enable-missing-tools` in CI, as this config option is no longer used. It also removes `dist.missing-tools` config completely.
Let me know which commits should I remove (if any).
Fixes: https://github.com/rust-lang/rust/issues/79249
r? `@onur-ozkan`