elaborate unknowable goals
A reimplemented version of #124532 affecting only the new solver. Always trying to prove super traits ends up causing a fatal overflow error in diesel, so we cannot land this in the old solver.
The following test currently does not pass coherence:
```rust
trait Super {}
trait Sub<T>: Super {}
trait Overlap<T> {}
impl<T, U: Sub<T>> Overlap<T> for U {}
impl<T> Overlap<T> for () {}
fn main() {}
```
We check whether `(): Sub<?t>` holds. This stalls with ambiguity as downstream crates may add an impl for `(): Sub<Local>`. However, its super trait bound `(): Super` cannot be implemented downstream, so this one is known not to hold.
By trying to prove that all the super bounds of a trait before adding a coherence unknowable candidate, this compiles. This is necessary to prevent breakage from enabling `-Znext-solver=coherence` (#121848), see tests/ui/coherence/super-traits/super-trait-knowable-2.rs for more details. The idea is that while there may be an impl of the trait itself we don't know about, if we're able to prove that a super trait is definitely not implemented, then that impl would also never apply/not be well-formed.
This approach is different from #124532 as it allows tests/ui/coherence/super-traits/super-trait-knowable-3.rs to compile. The approach in #124532 only elaborating the root obligations while this approach tries it for all unknowable trait goals.
r? `@compiler-errors`
Rollup of 6 pull requests
Successful merges:
- #126247 (rustdoc: word wrap CamelCase in the item list table and sidebar)
- #128104 (Not lint pub structs without pub constructors intentionally)
- #128153 (Stop using `MoveDataParamEnv` for places that don't need a param-env)
- #128284 (Stabilize offset_of_nested)
- #128342 (simplify the use of `CiEnv`)
- #128355 (triagebot: make sure Nora is called Nora)
r? `@ghost`
`@rustbot` modify labels: rollup
Stabilize offset_of_nested
Tracking issue #120140. Closes#120140.
As the FCP is now nearing its end I have opened a stabilization PR. I have done this separately to the offset_of_enum feature, since that FCP has not started.
`@rustbot` label F-offset_of_nested T-lang T-libs-api
Stop using `MoveDataParamEnv` for places that don't need a param-env
I think not threading through a `ParamEnv` makes it clearer that these functions don't do anything particularly "type systems"-y.
r? cjgillot
Make `rustc_attr::parse_version` pub
I'd like to use it in Clippy but I'll make those changes in the Clippy repo after the sync so it doesn't cause a conflict with https://github.com/rust-lang/rust-clippy/pull/13168
Tell users not to file a bug when using internal library features
Actually fixes#97501. I don't think we should suppress the suggestion to add `#![feature(..)]`, though I guess I could be convinced otherwise.
r? `@Nilstrieb` cc `@RalfJung`
Didn't add a test b/c I don't think we test this for lang features either, but I can confirm it does work.
```
warning: the feature `core_intrinsics` is internal to the compiler or standard library
--> /home/michael/test.rs:1:12
|
1 | #![feature(core_intrinsics)]
| ^^^^^^^^^^^^^^^
|
= note: using it is strongly discouraged
= note: `#[warn(internal_features)]` on by default
thread 'rustc' panicked at compiler/rustc_mir_transform/src/validate.rs:94:25:
broken MIR in Item(DefId(0:6 ~ test[42db]::{impl#0}::add)) (after phase change to runtime-optimized) at bb0[0]:
Cannot perform arithmetic Add on type WrapInt8
stack backtrace:
0: begin_panic_handler
at ./library/std/src/panicking.rs:665:5
1: panic_fmt
at ./library/core/src/panicking.rs:74:14
2: fail<alloc::string::String>
at ./compiler/rustc_mir_transform/src/validate.rs:146:9
3: run_pass
at ./compiler/rustc_mir_transform/src/validate.rs:94:13
4: validate_body
at ./compiler/rustc_mir_transform/src/pass_manager.rs:193:5
5: run_passes_inner
at ./compiler/rustc_mir_transform/src/pass_manager.rs:176:13
6: rustc_mir_transform::pass_manager::run_passes
at ./compiler/rustc_mir_transform/src/pass_manager.rs:87:5
7: run_optimization_passes
at ./compiler/rustc_mir_transform/src/lib.rs:561:5
8: inner_optimized_mir
at ./compiler/rustc_mir_transform/src/lib.rs:667:5
9: optimized_mir
at ./compiler/rustc_mir_transform/src/lib.rs:630:21
10: {closure#0}
at ./compiler/rustc_query_impl/src/plumbing.rs:285:13
[... omitted 22 frames ...]
11: query_get_at<rustc_query_system::query::caches::DefIdCache<rustc_middle::query::erase::Erased<[u8; 8]>>>
at ./compiler/rustc_middle/src/query/plumbing.rs:145:17
12: instance_mir
13: collect_items_of_instance
at ./compiler/rustc_monomorphize/src/collector.rs:1203:16
14: {closure#0}
at ./compiler/rustc_monomorphize/src/collector.rs:447:17
15: maybe_grow<(), rustc_monomorphize::collector::collect_items_rec::{closure_env#0}>
at /home/michael/.cargo/registry/src/index.crates.io-6f17d22bba15001f/stacker-0.1.15/src/lib.rs:55:9
16: ensure_sufficient_stack<(), rustc_monomorphize::collector::collect_items_rec::{closure_env#0}>
at ./compiler/rustc_data_structures/src/stack.rs:17:5
17: collect_items_rec
at ./compiler/rustc_monomorphize/src/collector.rs:446:13
18: collect_items_rec
at ./compiler/rustc_monomorphize/src/collector.rs:526:13
19: {closure#0}
at ./compiler/rustc_monomorphize/src/collector.rs:1597:17
20: {closure#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:182:34
21: call_once<(), rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure#0}::{closure_env#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>
at ./library/core/src/panic/unwind_safe.rs:272:9
22: do_call<core::panic::unwind_safe::AssertUnwindSafe<rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure#0}::{closure_env#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>, ()>
at ./library/std/src/panicking.rs:557:40
23: try<(), core::panic::unwind_safe::AssertUnwindSafe<rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure#0}::{closure_env#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>>
at ./library/std/src/panicking.rs:521:19
24: run<(), rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure#1}::{closure_env#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:28:9
25: {closure#1}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:186:21
26: {closure#0}<rustc_middle::mir::mono::MonoItem, rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure_env#1}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>
at ./library/core/src/iter/traits/iterator.rs:815:29
27: fold<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global, (), core::iter::traits::iterator::Iterator::for_each::call::{closure_env#0}<rustc_middle::mir::mono::MonoItem, rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure_env#1}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>>
at ./library/alloc/src/vec/into_iter.rs:317:25
28: for_each<alloc::vec::into_iter::IntoIter<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure#0}::{closure_env#1}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>
at ./library/core/src/iter/traits/iterator.rs:818:9
29: {closure#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:185:17
30: parallel_guard<(), rustc_data_structures::sync::parallel::enabled::par_for_each_in::{closure_env#0}<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:44:15
31: par_for_each_in<rustc_middle::mir::mono::MonoItem, alloc::vec::Vec<rustc_middle::mir::mono::MonoItem, alloc::alloc::Global>, rustc_monomorphize::collector::collect_crate_mono_items::{closure#1}::{closure_env#0}>
at ./compiler/rustc_data_structures/src/sync/parallel.rs:178:9
32: {closure#1}
at ./compiler/rustc_monomorphize/src/collector.rs:1595:13
33: run<(), rustc_monomorphize::collector::collect_crate_mono_items::{closure_env#1}>
at ./compiler/rustc_data_structures/src/profiling.rs:754:9
34: time<(), rustc_monomorphize::collector::collect_crate_mono_items::{closure_env#1}>
at ./compiler/rustc_session/src/utils.rs:16:9
35: collect_crate_mono_items
at ./compiler/rustc_monomorphize/src/collector.rs:1594:9
36: collect_and_partition_mono_items
at ./compiler/rustc_monomorphize/src/partitioning.rs:1124:30
37: {closure#0}
at ./compiler/rustc_query_impl/src/plumbing.rs:281:9
[... omitted 22 frames ...]
38: query_get_at<rustc_query_system::query::caches::SingleCache<rustc_middle::query::erase::Erased<[u8; 24]>>>
at ./compiler/rustc_middle/src/query/plumbing.rs:145:17
39: collect_and_partition_mono_items
at ./compiler/rustc_middle/src/query/plumbing.rs:423:31
40: collect_and_partition_mono_items
at ./compiler/rustc_middle/src/query/plumbing.rs:414:17
41: codegen_crate<rustc_codegen_llvm::LlvmCodegenBackend>
at ./compiler/rustc_codegen_ssa/src/base.rs:596:25
42: codegen_crate
at ./compiler/rustc_codegen_llvm/src/lib.rs:361:18
43: {closure#0}
at ./compiler/rustc_interface/src/passes.rs:1027:9
44: run<alloc::boxed::Box<dyn core::any::Any, alloc::alloc::Global>, rustc_interface::passes::start_codegen::{closure_env#0}>
at ./compiler/rustc_data_structures/src/profiling.rs:754:9
45: time<alloc::boxed::Box<dyn core::any::Any, alloc::alloc::Global>, rustc_interface::passes::start_codegen::{closure_env#0}>
at ./compiler/rustc_session/src/utils.rs:16:9
46: start_codegen
at ./compiler/rustc_interface/src/passes.rs:1026:19
47: codegen_and_build_linker
at ./compiler/rustc_interface/src/queries.rs:128:31
48: {closure#6}
at ./compiler/rustc_driver_impl/src/lib.rs:451:25
49: {closure#1}<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_middle/src/ty/context.rs:1336:37
50: {closure#0}<rustc_middle::ty::context::{impl#19}::enter::{closure_env#1}<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_middle/src/ty/context/tls.rs:82:9
51: try_with<core::cell::Cell<*const ()>, rustc_middle::ty::context::tls::enter_context::{closure_env#0}<rustc_middle::ty::context::{impl#19}::enter::{closure_env#1}<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./library/std/src/thread/local.rs:283:12
52: with<core::cell::Cell<*const ()>, rustc_middle::ty::context::tls::enter_context::{closure_env#0}<rustc_middle::ty::context::{impl#19}::enter::{closure_env#1}<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./library/std/src/thread/local.rs:260:9
53: enter_context<rustc_middle::ty::context::{impl#19}::enter::{closure_env#1}<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_middle/src/ty/context/tls.rs:79:5
54: enter<rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure_env#6}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_middle/src/ty/context.rs:1336:9
55: <rustc_interface::queries::QueryResult<&rustc_middle::ty::context::GlobalCtxt>>::enter::<core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure#6}>
at ./compiler/rustc_interface/src/queries.rs:64:9
56: {closure#1}
at ./compiler/rustc_driver_impl/src/lib.rs:450:13
57: enter<rustc_driver_impl::run_compiler::{closure#0}::{closure_env#1}, core::result::Result<core::option::Option<rustc_interface::queries::Linker>, rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_interface/src/queries.rs:209:19
58: {closure#0}
at ./compiler/rustc_driver_impl/src/lib.rs:388:22
59: {closure#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>
at ./compiler/rustc_interface/src/interface.rs:502:27
60: {closure#0}<rustc_interface::interface::run_compiler::{closure_env#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>, core::result::Result<(), rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_interface/src/util.rs:154:13
61: {closure#0}<rustc_interface::util::run_in_thread_pool_with_globals::{closure_env#0}<rustc_interface::interface::run_compiler::{closure_env#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>, core::result::Result<(), rustc_span::ErrorGuaranteed>>, core::result::Result<(), rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_interface/src/util.rs:106:21
62: set<rustc_span::SessionGlobals, rustc_interface::util::run_in_thread_with_globals::{closure#0}::{closure#0}::{closure_env#0}<rustc_interface::util::run_in_thread_pool_with_globals::{closure_env#0}<rustc_interface::interface::run_compiler::{closure_env#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>, core::result::Result<(), rustc_span::ErrorGuaranteed>>, core::result::Result<(), rustc_span::ErrorGuaranteed>>, core::result::Result<(), rustc_span::ErrorGuaranteed>>
at /home/michael/.cargo/registry/src/index.crates.io-6f17d22bba15001f/scoped-tls-1.0.1/src/lib.rs:137:9
63: create_session_globals_then<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_interface::util::run_in_thread_with_globals::{closure#0}::{closure#0}::{closure_env#0}<rustc_interface::util::run_in_thread_pool_with_globals::{closure_env#0}<rustc_interface::interface::run_compiler::{closure_env#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>, core::result::Result<(), rustc_span::ErrorGuaranteed>>, core::result::Result<(), rustc_span::ErrorGuaranteed>>>
at ./compiler/rustc_span/src/lib.rs:134:5
64: {closure#0}<rustc_interface::util::run_in_thread_pool_with_globals::{closure_env#0}<rustc_interface::interface::run_compiler::{closure_env#1}<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure_env#0}>, core::result::Result<(), rustc_span::ErrorGuaranteed>>, core::result::Result<(), rustc_span::ErrorGuaranteed>>
at ./compiler/rustc_interface/src/util.rs:105:17
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
error: the compiler unexpectedly panicked. this is a bug.
note: using internal features is not supported and expected to cause internal compiler errors when used incorrectly
note: rustc 1.82.0-dev running on x86_64-unknown-linux-gnu
query stack during panic:
#0 [optimized_mir] optimizing MIR for `<impl at /home/michael/test.rs:9:1: 9:32>::add`
#1 [collect_and_partition_mono_items] collect_and_partition_mono_items
end of query stack
```
Don't record trait aliases as marker traits
Don't record `#[marker]` on trait aliases, since we use that to check for the (non-presence of) associated types and other things which don't make sense of trait aliases. We already enforce this attr is only applied to a trait.
Also do the same for `#[const_trait]`, which we also enforce is only applied to a trait. This is a drive-by change, but also worthwhile just in case.
Fixes#127222
Don't elaborate associated types with Sized bounds in `trait_object_ty` in cfi
The elaboration mechanism introduced in #123005 didn't filter for associated types with `Self: Sized` bounds, which since #112319 has excluded them from the object type.
Fixes#127881
cc `@maurer` `@rcvalle`
Perform instsimplify before inline to eliminate some trivial calls
I am currently working on #128081. In the current pipeline, we can get the following clone statements ([godbolt](https://rust.godbolt.org/z/931316fhP)):
```
bb0: {
StorageLive(_2);
_2 = ((*_1).0: i32);
StorageLive(_3);
_3 = ((*_1).1: u64);
_0 = Foo { a: move _2, b: move _3 };
StorageDead(_3);
StorageDead(_2);
return;
}
```
Analyzing such statements will be simple and fast. We don't need to consider branches or some interfering statements. However, this requires us to run `InstSimplify`, `ReferencePropagation`, and `SimplifyCFG` at least once. I can introduce a new pass, but I think the best place for it would be within `InstSimplify`.
I put `InstSimplify` before `Inline`, which takes some of the burden away from `Inline`.
r? `@saethlin`
Isolate the diagnostic code that expects `thir::Pat` to be printable
Currently, `thir::Pat` implements `fmt::Display` (and `IntoDiagArg`) directly, for use by a few diagnostics.
That makes it tricky to experiment with alternate representations for THIR patterns, because the patterns currently need to be printable on their own. That immediately rules out possibilities like storing subpatterns as a `PatId` index into a central list (instead of the current directly-owned `Box<Pat>`).
This PR therefore takes an incremental step away from that obstacle, by removing `thir::Pat` from diagnostic structs in `rustc_pattern_analysis`, and hiding the pattern-printing process behind a single public `Pat::to_string` method. Doing so makes it easier to identify and update the code that wants to print patterns, and gives a place to pass in additional context in the future if necessary.
---
I'm currently not sure whether switching over to `PatId` is actually desirable or not, but I think this change makes sense on its own merits, by reducing the coupling between `thir::Pat` and the pattern-analysis error types.
miri: fix offset_from behavior on wildcard pointers
offset_from wouldn't behave correctly when the "end" pointer was a wildcard pointer (result of an int2ptr cast) just at the end of the allocation. Fix that by expressing the "same allocation" check in terms of two `check_ptr_access_signed` instead of something specific to offset_from, which is both more canonical and works better with wildcard pointers.
The second commit just improves diagnostics: I wanted the "pointer is dangling (has no provenance)" message to say how many bytes of memory it expected to see (since if it were 0 bytes, this would actually be legal, so it's good to tell the user that it's not 0 bytes). And then I was annoying that the error looks so different for when you deref a dangling pointer vs an out-of-bounds pointer so I made them more similar.
Fixes https://github.com/rust-lang/miri/issues/3767
Update compiler_builtins to 0.1.114
The `weak-intrinsics` feature was removed from compiler_builtins in https://github.com/rust-lang/compiler-builtins/pull/598, so dropped the `compiler-builtins-weak-intrinsics` feature from alloc/std/sysroot.
In https://github.com/rust-lang/compiler-builtins/pull/593, some builtins for f16/f128 were added. These don't work for all compiler backends, so add a `compiler-builtins-no-f16-f128` feature and disable it for cranelift and gcc.
This gives a clearer view of the (diagnostic) code that expects to be able to
print THIR patterns, and makes it possible to experiment with requiring some
kind of context (for ID lookup) when printing patterns.
The `weak-intrinsics` feature was removed from compiler_builtins in
https://github.com/rust-lang/compiler-builtins/pull/598, so dropped the
`compiler-builtins-weak-intrinsics` feature from alloc/std/sysroot.
In https://github.com/rust-lang/compiler-builtins/pull/593, some
builtins for f16/f128 were added. These don't work for all compiler
backends, so add a `compiler-builtins-no-f16-f128` feature and disable
it for cranelift and gcc. Also disable it for LLVM targets that don't
support it.
As decided in rust-lang/compiler-team#750.
Use declarations are currently wildly inconsistent because rustfmt is
quite unopinionated about how they should be formatted. The
`rustfmt.toml` additions makes rustfmt more opinionated, which avoids
the need for any decision when adding new use declarations to a file.
This commit only updates `rustfmt.toml` and
`compiler/rustc_codegen_cranelift/rustfmt.toml`. The next commit will do
the reformatting.
deps: dedup object, wasmparser, wasm-encoder
* dedups one `object`, additional dupe will be removed, with next `thorin-dwp` update
* `wasmparser` pinned to minor versions, so full merge isn't possible
* same with `wasm-encoder`
Turned off some features for `wasmparser` (see features https://github.com/bytecodealliance/wasm-tools/blob/v1.208.1/crates/wasmparser/Cargo.toml) in `run-make-support`, looks working?
Don't manually implement `PartialEq` for some types in `rustc_type_ir`
> > As a follow-up, we should look at not manually implementing PartialEq for these types but instead going thru a derive
>
> I will try to tackle this later in a separate PR
https://github.com/rust-lang/rust/issues/127042#issuecomment-2218838446
Add migration lint for 2024 prelude additions
This adds the migration lint for the newly ambiguous methods `poll` and `into_future`. When these methods are used on types implementing the respective traits, it will be ambiguous in the future, which can lead to hard errors or behavior changes depending on the exact circumstances.
tracked by #121042
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r? compiler-errors as the method prober
This adds the migration lint for the newly ambiguous methods `poll` and
`into_future`. When these methods are used on types implementing the
respective traits, it will be ambiguous in the future, which can lead to
hard errors or behavior changes depending on the exact circumstances.
`#[naked]`: report incompatible attributes
tracking issue: https://github.com/rust-lang/rust/issues/90957
this is a re-implementation of https://github.com/rust-lang/rust/pull/93809 by ``@bstrie`` which was closed 2 years ago due to inactivity.
This PR takes some of the final comments into account, specifically providing a little more context in error messages, and using an allow list to determine which attributes are compatible with `#[naked]`.
Notable attributes that are incompatible with `#[naked]` are:
* `#[inline]`
* `#[track_caller]`
* ~~`#[target_feature]`~~ (this is now allowed, see PR discussion)
* `#[test]`, `#[ignore]`, `#[should_panic]`
These attributes just directly conflict with what `#[naked]` should do.
Naked functions are still important for systems programming, embedded, and operating systems, so I'd like to move them forward.
Disable jump threading of float equality
Jump threading stores values as `u128` (`ScalarInt`) and does its comparisons for equality as integer comparisons.
This works great for integers. Sadly, not everything is an integer.
Floats famously have wonky equality semantcs, with `NaN!=NaN` and `0.0 == -0.0`. This does not match our beautiful integer bitpattern equality and therefore causes things to go horribly wrong.
While jump threading could be extended to support floats by remembering that they're floats in the value state and handling them properly, it's signficantly easier to just disable it for now.
fixes#128243
Remove logic to suggest clone of function output
I can't exactly tell, but I believe that this suggestion is operating off of a heuristic that the lifetime of a function's input is correlated with the lifetime of a function's output in such a way that cloning would fix an error. I don't think that actually manages to hit the bar of "actually provides useful suggestions" most of the time.
Specifically, I've hit false-positives due to this suggestion *twice* when fixing ICEs in the compiler, so I don't think it's worthwhile having this logic around. Neither of the two affected UI tests are actually fixed by the suggestion.
improve error message when `global_asm!` uses `asm!` options
specifically, what was
error: expected one of `)`, `att_syntax`, or `raw`, found `preserves_flags`
--> $DIR/bad-options.rs:45:25
|
LL | global_asm!("", options(preserves_flags));
| ^^^^^^^^^^^^^^^ expected one of `)`, `att_syntax`, or `raw`
is now
error: the `preserves_flags` option cannot be used with `global_asm!`
--> $DIR/bad-options.rs:45:25
|
LL | global_asm!("", options(preserves_flags));
| ^^^^^^^^^^^^^^^ the `preserves_flags` option is not meaningful for global-scoped inline assembly
mirroring the phrasing of the [reference](https://doc.rust-lang.org/reference/inline-assembly.html#options).
This is also a bit of a refactor for a future `naked_asm!` macro (for use in `#[naked]` functions). Currently this sort of error can come up when switching from inline to global asm, or when a user just isn't that experienced with assembly. With `naked_asm!` added to the mix hitting this error is more likely.
Jump threading stores values as `u128` (`ScalarInt`) and does its
comparisons for equality as integer comparisons.
This works great for integers. Sadly, not everything is an integer.
Floats famously have wonky equality semantcs, with `NaN!=NaN` and
`0.0 == -0.0`. This does not match our beautiful integer bitpattern
equality and therefore causes things to go horribly wrong.
While jump threading could be extended to support floats by remembering
that they're floats in the value state and handling them properly,
it's signficantly easier to just disable it for now.
Make `missing_fragment_specifier` an error in edition 2024
`missing_fragment_specifier` has been a future compatibility warning since 2017. Uplifting it to an unconditional hard error was attempted in 2020, but eventually reverted due to fallout.
Make it an error only in edition >= 2024, leaving the lint for older editions. This change will make it easier to support more macro syntax that relies on usage of `$`.
Fixes <https://github.com/rust-lang/rust/issues/40107>
---
It is rather late for the edition but since this change is relatively small, it seems worth at least bringing up. This follows a brief [Zulip discussion](https://rust-lang.zulipchat.com/#narrow/stream/268952-edition/topic/.60.20DBD.20-.3E.20hard.20error) (cc `@tmandry).`
Making this an edition-dependent lint has come up before but there was not a strong motivation. I am proposing it at this time because this would simplify the [named macro capture groups](https://github.com/rust-lang/rfcs/pull/3649) RFC, which has had mildly positive response, and makes use of new `$` syntax in the matcher. The proposed syntax currently parses as metavariables without a fragment specifier; this warning is raised, but there are no errors.
It is obviously not known that this specific RFC will eventually be accepted, but forbidding `missing_fragment_specifier` should make it easier to support any new syntax in the future that makes use of `$` in different ways. The syntax conflict is also not impossible to overcome, but making it clear that unnamed metavariables are rejected makes things more straightforward and should allow for better diagnostics.
`@Mark-Simulacrum` suggested making this forbid-by-default instead of an error at https://github.com/rust-lang/rust/issues/40107#issuecomment-761727885, but I don't think this would allow the same level of syntax flexibility.
It is also possible to reconsider making this an unconditional error since four years have elapsed since the previous attempt, but this seems likely to hit the same pitfalls. (Possibly worth a crater run?)
Tracking:
- https://github.com/rust-lang/rust/issues/128143
- merge error codes
- use attribute name that is incompatible in error message
- add test for conditional incompatible attribute
- add `linkage` to the allowlist
`missing_fragment_specifier` has been a future compatibility warning
since 2017. Uplifting it to an unconditional hard error was attempted in
2020, but eventually reverted due to fallout.
Make it an error only in edition >= 2024, leaving the lint for older
editions. This change will make it easier to support more macro syntax
that relies on usage of `$`.
Fixes <https://github.com/rust-lang/rust/issues/40107>
Improve `extern "<abi>" unsafe fn()` error message
These errors were already reported in #87217, and fixed by #87235 but missed the case of an explicit ABI.
This PR does not cover multiple keywords like `extern "C" pub const unsafe fn()`, but I don't know what a good way to cover this would be. It also seems rarer than `extern "C" unsafe` which I saw happen a few times in workshops.
