rustc: Fix `-Zexport-executable-symbols` on wasm
This commit reorders some cases in `export_symbols` in the linker implementation for wasm to ensure that the `is_like_wasm` case is handled before the catch-all `CrateType::Executable` case.
Remove out of date FIXME comment.
Commit https://github.com/rust-lang/rust/pull/147526 removed the following code and replaced it with the `AllocatorMethod`. However, its input is empty, resulting in behavior inconsistent with the previous code.
```rust
create_wrapper_function(
tcx,
&cx,
&mangle_internal_symbol(tcx, "__rust_alloc_error_handler"),
Some(&mangle_internal_symbol(tcx, alloc_error_handler_name(alloc_error_handler_kind))),
&[usize, usize], // size, align
None,
true,
&CodegenFnAttrs::new(),
);
```
resolves https://github.com/rust-lang/rust/issues/150755
naked functions: emit `.private_extern` on macos
fixes https://github.com/rust-lang/rust/issues/148307
Emit `.private_extern` on macos when the naked function uses `Linkage::Internal`. Failing to do so can cause issues with LTO.
The documentation on this directive is kind of sparse, but I believe this is at least not incorrect, and does fix the issue.
r? @Amanieu
cc @bjorn3
Merge `associated_const_equality` feature gate into MGCA
Tracking Issues: rust-lang/rust#132980rust-lang/rust#92827
Merge `associated_const_equality`(ACE) feature gate into `min_generic_const_args`(MGCA).
- Replaces `features().associated_const_equality()` checks with `features().min_generic_const_args()`
- Updates the parser to gate associated const equality under `min_generic_const_args`
- Moves `associated_const_equality` to the removed features list
- Removes the `associated_const_equality` method from the `Features` trait
- Updates all affected tests and tools (rust-analyzer, clippy)
Closesrust-lang/rust#150617
r? `@BoxyUwU`
This removes `associated_const_equality` as a separate feature gate and makes it part of `min_generic_const_args` (mgca).
Key changes:
- Remove `associated_const_equality` from unstable features, add to removed
- Update all test files to use `min_generic_const_args` instead
- Preserve the original "associated const equality is incomplete" error message by specially handling `sym::associated_const_equality` spans in `feature_gate.rs`
- Rename FIXME(associated_const_equality) to FIXME(mgca)
Stabilize 29 RISC-V target features (`riscv_ratified_v2`)
This commit stabilizes RISC-V target features with following constraints:
* Describes a ratified extension.
* Implemented on Rust 1.88.0 or before.
Waiting for four+ version cycles seems sufficient.
* Does not disrupt current rustc's target feature (cf. rust-lang/rust#140570) + ABI (cf. rust-lang/rust#132618) handling.
It excludes `E` and all floating point-arithmetic extensions. The `Zfinx` family does not involve floating point registers but not stabilizing for now to avoid possible confusion between the `F` extension family.
* Not vector-related (floating point and integer).
While integer vector subsets should not cause any ABI issues (as they don't use ABI-dependent floating point registers), we need to discuss before stabilizing them.
* Supported by the lowest LLVM version supported by rustc (LLVM 20).
List of target features to be stabilized:
1. `b`
2. `za64rs` (no-RT)
3. `za128rs` (no-RT)
4. `zaamo`
5. `zabha`
6. `zacas`
7. `zalrsc`
8. `zama16b` (no-RT)
9. `zawrs`
10. `zca`
11. `zcb`
12. `zcmop`
13. `zic64b` (no-RT)
14. `zicbom`
15. `zicbop` (no-RT)
16. `zicboz`
17. `ziccamoa` (no-RT)
18. `ziccif` (no-RT)
19. `zicclsm` (no-RT)
20. `ziccrse` (no-RT)
21. `zicntr`
22. `zicond`
23. `zicsr`
24. `zifencei`
25. `zihintntl`
26. `zihintpause`
27. `zihpm`
28. `zimop`
29. `ztso`
Of which, 20 of them (29 minus 9 "no-RT" target features) support runtime detection through `std::arch::is_riscv_feature_detected!()`.
Corresponding PR for the Reference: rust-lang/reference#1987
Port `#[instruction_set]` to attribute parser
Please note the test changes, and deprecation of `E0778` and `E0779`
In my opinion, all errors related to this attribute are improved I think, except for if you have `#[instruction_set(arm::)]` in which case there's an `error: expected identifier, found <eof>`, which is quite unhelpful I think, but this seems to be a limitation of the general attribute parsing flow
r? `@JonathanBrouwer`
As this is the only unwinding intrinsic we use and
codegen_llvm_intrinsic_call currently doesn't handle unwinding
intrinsics, this uses the conventional call path for llvm.wasm.throw.
Avoid using env::temp when linking a binary
This keeps all build artefacts (even temporary ones) within the build directory.
Fixesrust-lang/rust#139963
Replace Rvalue::NullaryOp by a variant in mir::Operand.
Based on https://github.com/rust-lang/rust/pull/148151
This PR fully removes the MIR `Rvalue::NullaryOp`. After rust-lang/rust#148151, it was only useful for runtime checks like `ub_checks`, `contract_checks` and `overflow_checks`.
These are "runtime" checks, boolean constants that may only be `true` in codegen. It depends on a rustc flag passed to codegen, so we need to represent those flags cross-crate.
This PR replaces those runtime checks by special variants in MIR `ConstValue`. This allows code that expects constants to manipulate those as such, even if we may not always be able to evaluate them to actual scalars.
This commit reorders some cases in `export_symbols` in the linker
implementation for wasm to ensure that the `is_like_wasm` case is
handled before the catch-all `CrateType::Executable` case.
LLVM doesn't handle stores on `<vscale x N x i1>` for `N != 16`, a type
used internally in SVE intrinsics. Spilling to the stack to create
debuginfo will cause errors during instruction selection. These types
that are an internal implementation detail to the intrinsic, so users
should never see them types and won't need any debuginfo.
Co-authored-by: Jamie Cunliffe <Jamie.Cunliffe@arm.com>
Introduces `BackendRepr::ScalableVector` corresponding to scalable
vector types annotated with `repr(scalable)` which lowers to a scalable
vector type in LLVM.
Co-authored-by: Jamie Cunliffe <Jamie.Cunliffe@arm.com>
Don't leak sysroot crates through dependencies
Previously if a dependency of the current crate depended on a sysroot crate, then `extern crate` would in the current crate would pick the first loaded version of said sysroot crate even in case of an ambiguity. This is surprising and brittle. For `-Ldependency=` we already blocked this since rust-lang/rust#110229, but the fix didn't account for sysroot crates.
Should fix https://github.com/rust-lang/rust/issues/147966
Externally implementable items
Supersedes https://github.com/rust-lang/rust/pull/140010
Tracking issue: https://github.com/rust-lang/rust/issues/125418
Getting started:
```rust
#![feature(eii)]
#[eii(eii1)]
pub fn decl1(x: u64)
// body optional (it's the default)
{
println!("default {x}");
}
// in another crate, maybe
#[eii1]
pub fn decl2(x: u64) {
println!("explicit {x}");
}
fn main() {
decl1(4);
}
```
- tiny perf regression, underlying issue makes multiple things in the compiler slow, not just EII, planning to solve those separately.
- No codegen_gcc support, they don't have bindings for weak symbols yet but could
- No windows support yet for weak definitions
This PR merges the implementation of EII for just llvm + not windows, doesn't yet contain like a new panic handler implementation or alloc handler. With this implementation, it would support implementing the panic handler in terms of EII already since it requires no default implementation so no weak symbols
The PR has been open in various forms for about a year now, but I feel that having some implementation merged to build upon
Make `--print=backend-has-zstd` work by default on any backend
Using a defaulted `CodegenBackend` method that querying for zstd support should automatically print a safe value of `false` on any backend that doesn't specifically indicate the presence or absence of zstd.
This should fix the compiletest failures reported in https://github.com/rust-lang/rust/pull/149666#discussion_r2597881482, which can occur when LLVM is not the default codegen backend.
Remove -Zoom=panic
There are major questions remaining about the reentrancy that this allows. It doesn't have any users on github outside of a single project that uses it in a panic=abort project to show backtraces. It can still be emulated through `#[alloc_error_handler]` or `set_alloc_error_hook` depending on if you use the standard library or not. And finally it makes it harder to do various improvements to the allocator shim.
With this PR the sole remaining symbol in the allocator shim that is not effectively emulating weak symbols is the symbol that prevents skipping the allocator shim on stable even when it would otherwise be empty because libstd + `#[global_allocator]` is used.
Closes https://github.com/rust-lang/rust/issues/43596
Fixes https://github.com/rust-lang/rust/issues/126683
Using a defaulted `CodegenBackend` method that querying for zstd support should
automatically print a safe value of `false` on any backend that doesn't
specifically indicate the presence or absence of zstd.
`c_variadic`: make `VaList` abi-compatible with C
tracking issue: https://github.com/rust-lang/rust/issues/44930
related PR: rust-lang/rust#144529
On some platforms, the C `va_list` type is actually a single-element array of a struct (on other platforms it is just a pointer). In C, arrays passed as function arguments expirience array-to-pointer decay, which means that C will pass a pointer to the array in the caller instead of the array itself, and modifications to the array in the callee will be visible to the caller (this does not match Rust by-value semantics). However, for `va_list`, the C standard explicitly states that it is undefined behaviour to use a `va_list` after it has been passed by value to a function (in Rust parlance, the `va_list` is moved, not copied). This matches Rust's pass-by-value semantics, meaning that when the C `va_list` type is a single-element array of a struct, the ABI will match C as long as the Rust type is always be passed indirectly.
In the old implementation, this ABI was achieved by having two separate types: `VaList` was the type that needed to be used when passing a `VaList` as a function parameter, whereas `VaListImpl` was the actual `va_list` type that was correct everywhere else. This however is quite confusing, as there are lots of footguns: it is easy to cause bugs by mixing them up (e.g. the C function `void foo(va_list va)` was equivalent to the Rust `fn foo(va: VaList)` whereas the C function `void bar(va_list* va)` was equivalent to the Rust `fn foo(va: *mut VaListImpl)`, not `fn foo(va: *mut VaList)` as might be expected); also converting from `VaListImpl` to `VaList` with `as_va_list()` had platform specific behaviour: on single-element array of a struct platforms it would return a `VaList` referencing the original `VaListImpl`, whereas on other platforms it would return a cioy,
In this PR, there is now just a single `VaList` type (renamed from `VaListImpl`) which represents the C `va_list` type and will just work in all positions. Instead of having a separate type just to make the ABI work, rust-lang/rust#144529 adds a `#[rustc_pass_indirectly_in_non_rustic_abis]` attribute, which when applied to a struct will force the struct to be passed indirectly by non-Rustic calling conventions. This PR then implements the `VaList` rework, making use of the new attribute on all platforms where the C `va_list` type is a single-element array of a struct.
Cleanup of the `VaList` API and implementation is also included in this PR: since it was decided it was OK to experiment with Rust requiring that not calling `va_end` is not undefined behaviour (https://github.com/rust-lang/rust/issues/141524#issuecomment-3028383594), I've removed the `with_copy` method as it was redundant to the `Clone` impl (the `Drop` impl of `VaList` is a no-op as `va_end` is a no-op on all known platforms).
Previous discussion: rust-lang/rust#141524 and [t-compiler > c_variadic API and ABI](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/c_variadic.20API.20and.20ABI)
Tracking issue: https://github.com/rust-lang/rust/issues/44930
r? `@joshtriplett`
misc coercion cleanups and handle safety correctly
r? lcnr
### "remove normalize call"
Fixesrust-lang/rust#132765
If the normalization fails we would sometimes get a `TypeError` containing inference variables created inside of the probe used by coercion. These would then get leaked out causing ICEs in diagnostics logic
### "leak check and lub for closure<->closure coerce-lubs of same defids"
Fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/233
```rust
fn peculiar() -> impl Fn(u8) -> u8 {
return |x| x + 1
}
```
the `|x| x + 1` expr has a type of `Closure(?31t)` which we wind up inferring the RPIT to. The `CoerceMany` `ret_coercion` for the whole `peculiar` typeck has an expected type of `RPIT` (unnormalized). When we type check the `return |x| x + 1` expr we go from the never type to `Closure(?31t)` which then participates in the `ret_coercion` giving us a `coerce-lub(RPIT, Closure(?31t))`.
Normalizing `RPIT` gives us some `Closure(?50t)` where `?31t` and `?50t` have been unified with `?31t` as the root var. `resolve_vars_if_possible` doesn't resolve infer vars to their roots so these wind up with different structural identities so the fast path doesn't apply and we fall back to coercing to a `fn` ptr. cc rust-lang/rust#147193 which also fixes this
New solver probably just gets more inference variables here because canonicalization + generally different approach to normalization of opaques. Idk :3
### FCP worthy stuffy
there are some other FCP worthy things but they're in my FCP comment which also contains some analysis of the breaking nature of the previously listed changes in this PR: https://github.com/rust-lang/rust/pull/148602#issuecomment-3503497467
There are major questions remaining about the reentrancy that this
allows. It doesn't have any users on github outside of a single project
that uses it in a panic=abort project to show backtraces. It
can still be emulated through #[alloc_error_handler] or
set_alloc_error_hook depending on if you use the standard library or
not. And finally it makes it harder to do various improvements to the
allocator shim.
Port the `#![windows_subsystem]` attribute to the new attribute system
Part of rust-lang/rust#131229.
I think it's worth running the Windows test suite before merging that (I don't have the rights for this).
It is never used anywhere anymore now that existing_matches doesn't use
it anymore. And there is no good reason for any other code to use it in
the future either.
Matthias Krüger