Add x86_64-unknown-linux-gnu{m,t}san target which enables {M,T}San by default
Analogous to the ASan target (https://github.com/rust-lang/rust/pull/149644), this adds targets for MSan and TSan.
As suggested, in order to distribute sanitizer instrumented standard libraries without introducing new rustc flags, this adds a new dedicated target. With the target, we can distribute the instrumented standard libraries through a separate rustup component.
> A tier 2 target must have value to people other than its maintainers. (It may still be a niche target, but it must not be exclusively useful for an inherently closed group.)
The target is useful to anyone who wants to use MSan/TSan with a stable compiler or the ease to not have to recompiled all standard libraries for full coverage.
> A tier 2 target must have a designated team of developers (the “target maintainers”) available to consult on target-specific build-breaking issues, or if necessary to develop target-specific language or library implementation details. This team must have at least 2 developers.
> * The target maintainers should not only fix target-specific issues, but should use any such issue as an opportunity to educate the Rust community about portability to their target, and enhance documentation of the target.
I pledge myself and the folks from the Exploit Mitigations Project Group (rcvalle@ & 1c3t3a@) as target maintainers to fix target-specific issues and educate the Rust community about their use.
> The target must not place undue burden on Rust developers not specifically concerned with that target. Rust developers are expected to not gratuitously break a tier 2 target, but are not expected to become experts in every tier 2 target, and are not expected to provide target-specific implementations for every tier 2 target.
Understood. The target should not have negative impact for anyone not using it.
> The target must provide documentation for the Rust community explaining how to build for the target using cross-compilation, and explaining how to run tests for the target. If at all possible, this documentation should show how to run Rust programs and tests for the target using emulation, to allow anyone to do so. If the target cannot be feasibly emulated, the documentation should explain how to obtain and work with physical hardware, cloud systems, or equivalent.
`src/doc/rustc/src/platform-support/x86_64-unknown-linux-gnu{m,t}san.md` should provide the necessary documentation on how to build the target or compile programs with it. In the way the target can be emulated it should not differ from the tier 1 target `x86_64-unknown-linux-gnu`.
> The target must document its baseline expectations for the features or versions of CPUs, operating systems, libraries, runtime environments, and similar.
The baseline expectation mirror `x86_64-unknown-linux-gnu`.
> If introducing a new tier 2 or higher target that is identical to an existing Rust target except for the baseline expectations for the features or versions of CPUs, operating systems, libraries, runtime environments, and similar, then the proposed target must document to the satisfaction of the approving teams why the specific difference in baseline expectations provides sufficient value to justify a separate target.
> * Note that in some cases, based on the usage of existing targets within the Rust community, Rust developers or a target’s maintainers may wish to modify the baseline expectations of a target, or split an existing target into multiple targets with different baseline expectations. A proposal to do so will be treated similarly to the analogous promotion, demotion, or removal of a target, according to this policy, with the same team approvals required.
> * For instance, if an OS version has become obsolete and unsupported, a target for that OS may raise its baseline expectations for OS version (treated as though removing a target corresponding to the older versions), or a target for that OS may split out support for older OS versions into a lower-tier target (treated as though demoting a target corresponding to the older versions, and requiring justification for a new target at a lower tier for the older OS versions).
This has been outlined sufficiently. We should not enable MSan/TSan in the default target and are therefore creating a new tier 2 target to bridge the gap until `build-std` stabilized.
> Tier 2 targets must not leave any significant portions of core or the standard library unimplemented or stubbed out, unless they cannot possibly be supported on the target.
> * The right approach to handling a missing feature from a target may depend on whether the target seems likely to develop the feature in the future. In some cases, a target may be co-developed along with Rust support, and Rust may gain new features on the target as that target gains the capabilities to support those features.
> * As an exception, a target identical to an existing tier 1 target except for lower baseline expectations for the OS, CPU, or similar, may propose to qualify as tier 2 (but not higher) without support for std if the target will primarily be used in no_std applications, to reduce the support burden for the standard library. In this case, evaluation of the proposed target’s value will take this limitation into account.
All of std that is supported by `x86_64-unknown-linux-gnu` is also supported.
> The code generation backend for the target should not have deficiencies that invalidate Rust safety properties, as evaluated by the Rust compiler team. (This requirement does not apply to arbitrary security enhancements or mitigations provided by code generation backends, only to those properties needed to ensure safe Rust code cannot cause undefined behavior or other unsoundness.) If this requirement does not hold, the target must clearly and prominently document any such limitations as part of the target’s entry in the target tier list, and ideally also via a failing test in the testsuite. The Rust compiler team must be satisfied with the balance between these limitations and the difficulty of implementing the necessary features.
> * For example, if Rust relies on a specific code generation feature to ensure that safe code cannot overflow the stack, the code generation for the target should support that feature.
> * If the Rust compiler introduces new safety properties (such as via new capabilities of a compiler backend), the Rust compiler team will determine if they consider those new safety properties a best-effort improvement for specific targets, or a required property for all Rust targets. In the latter case, the compiler team may require the maintainers of existing targets to either implement and confirm support for the property or update the target tier list with documentation of the missing property.
The entire point is to have more security instead of less ;) The safety properties provided are already present in the compiler, just not enabled by default.
> If the target supports C code, and the target has an interoperable calling convention for C code, the Rust target must support that C calling convention for the platform via extern "C". The C calling convention does not need to be the default Rust calling convention for the target, however.
Understood.
> The target must build reliably in CI, for all components that Rust’s CI considers mandatory.
Understood and the reason for introducing the tier 2 target.
> The approving teams may additionally require that a subset of tests pass in CI, such as enough to build a functional “hello world” program, ./x.py test --no-run, or equivalent “smoke tests”. In particular, this requirement may apply if the target builds host tools, or if the tests in question provide substantial value via early detection of critical problems.
Understood.
> Building the target in CI must not take substantially longer than the current slowest target in CI, and should not substantially raise the maintenance burden of the CI infrastructure. This requirement is subjective, to be evaluated by the infrastructure team, and will take the community importance of the target into account.
Understood.
> Tier 2 targets should, if at all possible, support cross-compiling. Tier 2 targets should not require using the target as the host for builds, even if the target supports host tools.
Understood. No need to use this target as the host (no benefit of having MSan/TSan enabled for compiling).
> In addition to the legal requirements for all targets (specified in the tier 3 requirements), because a tier 2 target typically involves the Rust project building and supplying various compiled binaries, incorporating the target and redistributing any resulting compiled binaries (e.g. built libraries, host tools if any) must not impose any onerous license requirements on any members of the Rust project, including infrastructure team members and those operating CI systems. This is a subjective requirement, to be evaluated by the approving teams.
> * As an exception to this, if the target’s primary purpose is to build components for a Free and Open Source Software (FOSS) project licensed under “copyleft” terms (terms which require licensing other code under compatible FOSS terms), such as kernel modules or plugins, then the standard libraries for the target may potentially be subject to copyleft terms, as long as such terms are satisfied by Rust’s existing practices of providing full corresponding source code. Note that anything added to the Rust repository itself must still use Rust’s standard license terms.
Understood, no legal differences between this target and `x86_64-unknown-linux-gnu`.
> Tier 2 targets must not impose burden on the authors of pull requests, or other developers in the community, to ensure that tests pass for 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 tests failing for the target. Do not send automated messages or notifications (via any medium, including via @) to a PR author or others involved with a PR regarding the PR breaking tests on a tier 2 target, unless they have opted into such messages.
> * 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.
Understood.
> The target maintainers should regularly run the testsuite for the target, and should fix any test failures in a reasonably timely fashion.
Understood.
> All requirements for tier 3 apply.
Requirements for tier 3 are listed below.
> 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.)
I pledge to do my best maintaining it and we can also include the folks from the Exploit Mitigations Project Group (rcvalle@ & 1c3t3a@).
> 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.
We've chosen `x86_64-unknown-linux-gnu{m,t}san` as the name which was suggested on [#t-compiler/major changes > Create new Tier 2 targets with sanitizers… compiler-team#951 @ 💬](https://rust-lang.zulipchat.com/#narrow/channel/233931-t-compiler.2Fmajor-changes/topic/Create.20new.20Tier.202.20targets.20with.20sanitizers.E2.80.A6.20compiler-team.23951/near/564482315). We've merged `x86_64-unknown-linux-gnuasan` and are now following up with the MSan and TSan targets
> 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.
There should be no confusion, it's clear that it's the original target with MSan/TSan enabled.
> If possible, use only letters, numbers, dashes and underscores for the name. Periods (.) are known to cause issues in Cargo.
Only letters, numbers and dashes used.
> 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.
There are no unusual requirements to build or use it. It's the original `x86_64-unknown-linux-gnu` target with MSan/TSan enabled as a default sanitizer.
> The target must not introduce license incompatibilities.
There are no license implications.
> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
Given, by reusing the existing MSan/TSan code.
> 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.
There are no new dependencies/features required.
> 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.
It's using open source tools only.
> "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.
Understood.
> 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.
Understood.
> 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 goal is to have MSan/TSan instrumented standard library variants of the existing `x86_64-unknown-linux-gnu` target, so all should be present.
> 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.
I think the explanation in platform support doc is enough to make this aspect clear.
> 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.
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.
Understood.
> 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.
Understood.
> 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.
I don't believe this PR is affected by this.
> Tier 3 targets must be able to produce assembly using at least one of rustc's supported backends from any host target. (Having support in a fork of the backend is not sufficient, it must be upstream.)
The target should work on all rustc versions that correctly compile for `x86_64-unknown-linux-gnu`.
Require avxvnni for avx10.2
AVX10.2 supports masked (and 512-bit) versions of some intrinsics available in AVXVNNI, AVXVNNIINT8 and AVXVNNIINT16 (e.g. AVX10.2 introduces `_mm{,256,512}_{mask{z}}_dpbuud_epi32` corresponding to `_mm{,256}_dpbuud_epi32` from AVXVNNIINT8). But Intel (being Intel), didn't (at least not in SDM) enforce that AVX10.2 (or at least AVX10_VNNI_INT, which is a "discrete AVX10 feature", introduced alongside AVX10.2, and expected to house more such instructions) requires AVXVNNI etc.
To make this (admittedly very Intel) situation a bit better, we can just require these features from the Rust frontend
r? @Amanieu
This also corrects a mistake in std-detect which allowed AVX10 to be enabled without AVX512F, in the (odd) case when F16C or FMA are not available (we require these for AVX512F because otherwise the LLVM assembler doesn't work)
Add `-Zsanitize=kernel-hwaddress`
The Linux kernel has a config option called `CONFIG_KASAN_SW_TAGS` that enables `-fsanitize=kernel-hwaddress`. This is not supported by Rust.
One slightly awkward detail is that `#[sanitize(address = "off")]` applies to both `-Zsanitize=address` and `-Zsanitize=kernel-address`. Probably it was done this way because both are the same LLVM pass. I replicated this logic here for hwaddress, but it might be undesirable.
Note that `#[sanitize(kernel_hwaddress = "off")]` could be supported as an annotation on statics, but since it's also missing for `#[sanitize(hwaddress = "off")]`, I did not add it.
MCP: https://github.com/rust-lang/compiler-team/issues/975
Tracking issue: https://github.com/rust-lang/rust/issues/154171
cc @rcvalle @maurer @ojeda
[BPF] add target feature allows-misaligned-mem-access
This PR adds the allows-misaligned-mem-access target feature to the BPF target. The feature can enable misaligned memory access support in the LLVM backend, aligning Rust’s BPF target behavior with the corresponding LLVM update introduced in [llvm/llvm-project#167013](https://github.com/llvm/llvm-project/pull/167013) (included in LLVM 22).
target specs: stricter checks for LLVM ABI values, and correlate that with cfg(target_abi)
This tightens the checks for `llvm_abiname`, `llvm_floatabi` and `rustc_abi` in our target specs. Those are the fields that actually control the ccABI. With this commit, we now have an allowlist of value for these fields for all architectures (we previously only had that for some architectures). We also check that `cfg(target_abi)` suitably correlates with the actual ccABI. I based this check on our in-tree targets. For all ccABIs where we had a bunch of "random" values that don't directly correlate to the ccABI (like "uwp"), I also allowed `cfg(target_abi)` to remain empty, and whenever it is allowed to be empty I also allowed arbitrary other values for JSON targets. However, there's still a risk that JSON targets will fail this new check -- the idea is that we'll then get bugreports and can adjust the check as needed.
I had to adjust the target specs for non-ARM32 Apple targets as those were all setting `llvm_floatabi`, which to my knowledge makes no sense -- LLVM only actually does anything with that field on ARM32. I also adjusted the target specs for MIPS32 targets: one of them was setting llvm_abiname, and then it seems safer and more consistent to set that for all targets, so I set it to "o32" everywhere which seems to be the default.
Cc @workingjubilee
Fix Hexagon ABI calling convention for small aggregates
Small structs (<= 64 bits) were being passed with their fields split into separate arguments instead of being packed into register-sized chunks. This caused ABI mismatches.
The fix properly casts small aggregates to consecutive register-sized chunks using Uniform::consecutive(), matching the Hexagon C ABI where small structs are packed into R1:0 register pair.
This fixes tests like extern-pass-TwoU16s.rs and extern-pass-TwoU8s.rs.
Similar like we've done it for `x86_64-unknown-linux-gnuasan`, in order
to distribute sanitizer instrumented standard libraries without
introducing new rustc flags, this adds a new dedicated target. With the
target, we can distribute the instrumented standard libraries through
a separate rustup component.
ast_passes: unsupported arch w/ scalable vectors
Fixesrust-lang/rust#153593
Emit an error when attempting to compile a `#[rustc_scalable_vector]` type for a architecture that fundamentally doesn't support scalable vectors. Ultimately this is just a diagnostic improvement for an internal attribute as users should never be doing this.
r? @lqd
Emit an error when attempting to compile a `#[rustc_scalable_vector]`
type for a architecture that fundamentally doesn't support scalable
vectors. Ultimately this is just a diagnostic improvement for an internal
attribute as users should never be doing this.
x86: reserve `bl` and `bh` registers to match `rbx`
`bl` and `bh` need to be explicitly marked as reserved, as they are sub-registers of `rbx`, which is reserved by LLVM.
Discovered this while trying to run Graviola through Cranelift, which was becoming corrupted due to the register allocator assigning `bl`: https://github.com/rust-lang/rustc_codegen_cranelift/pull/1629
cc: @bjorn3
prefer actual ABI-controling fields over target.abi when making ABI decisions
We don't actually check that `abi` is consistent with the fields that control the ABI, e.g. one could set `llvm_abiname` to "ilp32e" on a riscv target without setting a matching `abi`. So, if we need to make actual decisions, better to use the source of truth we forward to LLVM than the informational string we forward to the user.
This is a breaking change for aarch64 JSON target specs: setting `abi` to "softfloat" is no longer enough; one has to also set `rustc_abi` to "softfloat". That is consistent with riscv and arm32, but it's still surprising. Cc @Darksonn in case this affects the Linux kernel.
Also see https://github.com/rust-lang/rust/pull/153035 which does something similar for PowerPC, and [Zulip](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/De-spaghettifying.20ABI.20controls/with/575095372). Happy to delay this PR if someone has a better idea.
Cc @folkertdev @workingjubilee
perf(codegen): Restore `noundef` On `PassMode::Cast` Args In Rust ABI
### Summary:
#### Problem:
Small aggregate arguments passed via `PassMode::Cast` in the Rust ABI (e.g. `[u32; 2]` cast to `i64`) are missing `noundef` in the emitted LLVM IR, even when the type contains no uninit bytes:
```rust
#[no_mangle]
pub fn f(v: [u32; 2]) -> u32 { v[0] }
```
```llvm
; expected: define i32 @f(i64 noundef %0)
; actual: define i32 @f(i64 %0) ← noundef missing
```
This blocks LLVM from applying optimizations that require value-defined semantics on function arguments.
#### Root Cause:
`adjust_for_rust_abi` calls `arg.cast_to(Reg::Integer)`, which internally creates a `CastTarget` with `ArgAttributes::new()` — always empty. Any validity attribute that was present before the cast is silently dropped.
This affects all `PassMode::Cast` arguments and return values in the Rust ABI: plain arrays, newtype wrappers, and any `BackendRepr::Memory` type small enough to fit in a register.
A prior attempt (rust-lang/rust#127210) used `Ty`/`repr` attributes to detect padding.
#### Solution:
After `adjust_for_rust_abi`, iterate all `PassMode::Cast` args and the return value. For each, call `layout_is_noundef` on the original layout; if it returns `true`, set `NoUndef` on the `CastTarget`'s `attrs`.
`layout_is_noundef` uses only the computed layout — `BackendRepr`, `FieldsShape`, `Variants`, `Scalar::is_uninit_valid()` — and never touches `Ty` or repr attributes. **Anything it cannot prove returns `false`.**
Covered cases:
- `Scalar` / `ScalarPair` (both halves initialized, fields contiguous)
- `FieldsShape::Array` (element type recursively uninit-free)
- `FieldsShape::Arbitrary` with `Variants::Single` (fields cover `0..size` with no gaps, each recursively uninit-free) — handles newtype wrappers, multi-field structs, single-variant enums, `repr(transparent)`, `repr(C)` wrappers
Conservatively excluded with FIXMEs:
- Multi-variant enums (per-variant padding analysis needed)
- Foreign-ABI casts (cast target may exceed layout size, needs a size guard)
### Changes:
- `compiler/rustc_ty_utils/src/abi.rs`: add restoration loop after `adjust_for_rust_abi`; add `layout_is_noundef` and `fields_cover_layout`.
- `tests/codegen-llvm/abi-noundef-cast.rs`: new FileCheck test covering arrays, newtype wrappers (`repr(Rust)`, `repr(transparent)`, `repr(C)`), multi-field structs, single-variant enums, return values, and negative cases (`MaybeUninit`, struct with trailing padding).
- `tests/codegen-llvm/debuginfo-dse.rs`: update one CHECK pattern — `Aggregate_4xi8` (`struct { i8, i8, i8, i8 }`) now correctly gets `noundef`.
Fixesrust-lang/rust#123183.
r? @RalfJung
`adjust_for_rust_abi` was casting small aggregates to an integer register
without propagating `noundef`, causing a performance regression (#123183)
— LLVM could no longer assume the bits were fully defined.
Add `layout_is_noundef` (conservative) + `fields_are_noundef` helper,
then use `cast_to_with_attrs` to forward `NoUndef` when proven:
Scalar → `!is_uninit_valid()`
ScalarPair → both scalars valid + `s1.size + s2.size == layout.size`
(size equality rejects layouts with inter-scalar padding)
Array → recurse into element; empty arrays unconditionally noundef
Arbitrary → `Variants::Single` required; walk fields in offset order —
any gap, non-noundef field, or trailing pad returns false
Union / Primitive / Simd → false (conservative)
Bless `pass-indirectly-attr.stderr` and `debuginfo-dse.rs` for the new
attribute on Cast args. Add `tests/codegen-llvm/abi-noundef-cast.rs`
covering positive Cast cases (arrays, plain structs, single-variant enum)
and negative Cast cases (MaybeUninit, multi-variant enum, field/pair gap,
trailing padding).
Fixes#123183.
Co-authored-by: Ralf Jung <post@ralfj.de>
Currently on PowerPC64 targets, llvm_abiname and target_abi will be the
same unless we're on AIX. Since llvm_abiname is what we pass on to LLVM,
it is preferable to use the value of that to determine the calling
convention rather than target_abi.
All PowerPC64 targets set both llvm_abiname and target_abi to the
respective ELF ABIs, with the exception of AIX. This is a non-functional
change.
Use `HashStable` derive in more places
This applies `HashStable` derive in a couple more places. Also `stable_hasher` is declared for `HashStable_NoContext`.
rustc_target: callconv: powerpc64: Use the ABI set in target options instead of guessing
All PowerPC64 targets except AIX explicitly set the ABI in the target options. We can therefore stop hardcoding the ABI to be used based on the target environment or OS, except for the AIX special case.
The fallback based on endianness is kept for the sake of compatibility with custom targets.
This makes it so that big endian targets not explicitly accounted for before (powerpc64-unknown-openbsd) and targets that don't use the expected default ABI (big-endian ELFv2 Glibc targets) use the correct ABI in the calling convention code.
The second commit is a tiny change to validate the `llvm_abiname` set on PowerPC64(LE) targets. See the commit messages for details.
CC @RalfJung who pointed out the missing `llvm_abiname` validation
Add 2048-bit HvxVectorPair support to Hexagon SIMD ABI checks
Previously, rustc rejected HvxVectorPair types in function signatures because the HEXAGON_FEATURES_FOR_CORRECT_FIXED_LENGTH_VECTOR_ABI array only had entries for vectors up to 1024 bits. This caused the ABI checker to emit "unsupported vector type" errors for 2048-bit HvxVectorPair (used in 128-byte HVX mode).
Add 2048 byte entry to allow HvxVectorPair to be passed in extern "C" funcs when the hvx-length128b is enabled.
Previously, rustc rejected HvxVectorPair types in function signatures
because the HEXAGON_FEATURES_FOR_CORRECT_FIXED_LENGTH_VECTOR_ABI array
only had entries for vectors up to 1024 bits. This caused the ABI checker
to emit "unsupported vector type" errors for 2048-bit HvxVectorPair
(used in 128-byte HVX mode).
Add 2048 byte entry to allow HvxVectorPair to be passed
in extern "C" funcs when the hvx-length128b is enabled.
Add `s390x-unknown-none-softfloat` with `RustcAbi::Softfloat`
followup on rust-lang/rust#150766
add an `s390x-unknown-none-softfloat` target to use for kernel compilation, as the Linux kernel does not wish to pay the overhead of saving float registers by default on kernel switch. this target's `extern "C"` ABI is unspecified, so it is unstable and subject to change between versions, just like the Linux intrakernel ABI and `extern "Rust"` ABIs are unstable.
enforce target feature incompatibility by adding `RustcAbi::Softfloat`. this is itself just a rename of `RustcAbi::X86Softfloat`, accepting both "x86-softfloat" and "softfloat" as valid strings in the target.json format. the target-features of `"soft-float"` and `"vector"` are incompatible for s390x, so issue a compatibility warning if they are combined.
Set crt_static_allow_dylibs to true for Emscripten target
And add a test. This is followup work to rust-lang/rust#151704. It introduced a regression where cargo is now unwilling to build cdylibs for Emscripten because `crt_static_default` is `true` but `crt_static_allows_dylibs` is `false`. Unfortunately the added test does not fail without the change because the validation logic is in Cargo, not in rustc. But it's good to have some coverage of this anyways.
This target is intended to be used for kernel development. Becasue on s390x
float and vector registers overlap we have to disable the vector extension.
The default s390x-unknown-gnu-linux target will not allow use of
softfloat.
Co-authored-by: Jubilee <workingjubilee@gmail.com>
And add a test. This is followup work to PR 151704. It introduced a regression where
cargo is now unwilling to build cdylibs for Emscripten because `crt_static_default` is
`true` but `crt_static_allows_dylibs` is `false`. Unfortunately the added test does not
fail without the change because the validation logic is in Cargo, not in rustc. But it's
good to have some coverage of this anyways.
Update hexagon target linker configurations
* hexagon-unknown-qurt: Use hexagon-clang from Hexagon SDK instead of rust-lld
* hexagon-unknown-linux-musl: Use hexagon-unknown-linux-musl-clang from the open source toolchain instead of rust-lld.
* hexagon-unknown-none-elf: Keep rust-lld but fix the linker flavor.
rust-lld is appropriate for a baremetal target but for traditional programs that depend on libc, using clang's driver makes the most sense.
Jonathan Brouwer