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2025-10-02Auto merge of #147055 - beepster4096:subtype_is_not_a_projection, r=lcnrbors-4/+1
Turn ProjectionElem::Subtype into CastKind::Subtype I noticed that drop elaboration can't, in general, handle `ProjectionElem::SubType`. It creates a disjoint move path that overlaps with other move paths. (`Subslice` does too, and I'm working on a different PR to make that special case less fragile.) If its skipped and treated as the same move path as its parent then `MovePath.place` has multiple possible projections. (It would probably make sense to remove all `Subtype` projections for the canonical place but it doesn't make sense to have this special case for a problem that doesn't actually occur in real MIR.) The only reason this doesn't break is that `Subtype` is always the sole projection of the local its applied to. For the same reason, it works fine as a `CastKind` so I figured that makes more sense than documenting and validating this hidden invariant. cc rust-lang/rust#112651, rust-lang/rust#133258 r? Icnr (bc you've been the main person dealing with `Subtype` it looks like)
2025-09-28remove explicit deref of AbiAlign for most methodsJubilee Young-3/+3
Much of the compiler calls functions on Align projected from AbiAlign. AbiAlign impls Deref to its inner Align, so we can simplify these away. Also, it will minimize disruption when AbiAlign is removed. For now, preserve usages that might resolve to PartialOrd or PartialEq, as those have odd inference.
2025-09-26Apply cfg(bootstrap) replacementMark Rousskov-1/+0
2025-09-26ProjectionElem::Subtype -> CastKind::Subtypebeepster4096-4/+1
2025-09-26Rollup merge of #146991 - cachebag:span-caller-location, r=RalfJungMatthias Krüger-1/+1
const_caller_location to use real Span instead of `DUMMY_SP` Clarifying usage of DUMMY_SP
2025-09-25const_caller_location: edit FIXME to explain use of `DUMMY_SP`Akrm Al-Hakimi-1/+1
Co-authored-by: Ralf Jung <post@ralfj.de>
2025-09-25Rollup merge of #146735 - Qelxiros:const_mul_add, r=tgross35,RalfJungStuart Cook-0/+54
unstably constify float mul_add methods Tracking issue: rust-lang/rust#146724 r? `@tgross35`
2025-09-24unstably constify float mul_add methodsJeremy Smart-0/+54
Co-authored-by: Ralf Jung <post@ralfj.de>
2025-09-24const validation: better error for maybe-null referencesRalf Jung-9/+24
2025-09-24const-eval: improve and actually test the errors when pointers might be ↵Ralf Jung-10/+6
outside the range of a scalar
2025-09-18Rollup merge of #146597 - modhanami:add-struct-tail-recursion-limit-span, ↵Matthias Krüger-0/+2
r=oli-obk Add span for struct tail recursion limit error Fixes rust-lang/rust#135629 Changes 1. Add span to RecursionLimitReached 2. Add ObligationCause parameter to struct_tail_raw 4. Update call sites to pass nearby ObligationCause or create one 5. Update affected .stderr
2025-09-18Rollup merge of #146664 - fmease:clean-up-dyn, r=jdonszelmannStuart Cook-12/+12
Clean up `ty::Dynamic` 1. As a follow-up to PR rust-lang/rust#143036, remove `DynKind` entirely. 2. Inside HIR ty lowering, consolidate modules `dyn_compatibility` and `lint` into `dyn_trait` * `dyn_compatibility` wasn't about dyn compatibility itself, it's about lowering trait object types * `lint` contained dyn-Trait-specific diagnostics+lints only
2025-09-17Auto merge of #146331 - RalfJung:copy-prov-repeat, r=oli-obkbors-2/+2
interpret: copy_provenance: avoid large intermediate buffer for large repeat counts Copying provenance worked in this odd way where the "preparation" phase (which is supposed to just extract the necessary information from the source range) already did all the work of repeating the result N times for the target range. This was needed to use the existing `insert_presorted` function on `SortedMap`. This PR generalizes `insert_presorted` so that we can avoid this odd structure on copy-provenance, and maybe even improve performance.
2025-09-17Remove `DynKind`León Orell Valerian Liehr-12/+12
2025-09-16Remove Rvalue::Len.Camille Gillot-13/+3
2025-09-16Add span for struct tail recursion limit errorTawan Muadmuenwai-0/+2
2025-09-16Rollup merge of #146402 - RalfJung:aggregate-init, r=saethlinStuart Cook-4/+14
interpret: fix overlapping aggregate initialization This fixes the problem pointed out by ````@saethlin```` in https://github.com/rust-lang/rust/issues/146383#issuecomment-3273224645. Also clarify when exactly current de-facto MIR semantics allow overlap of the LHS and RHS in an assignment.
2025-09-10interpret: fix overlapping aggregate initializationRalf Jung-4/+14
2025-09-10Rollup merge of #146178 - folkertdev:static-align, ↵Matthias Krüger-2/+10
r=jdonszelmann,ralfjung,traviscross Implement `#[rustc_align_static(N)]` on `static`s Tracking issue: https://github.com/rust-lang/rust/issues/146177 ```rust #![feature(static_align)] #[rustc_align_static(64)] static SO_ALIGNED: u64 = 0; ``` We need a different attribute than `rustc_align` because unstable attributes are tied to their feature (we can't have two unstable features use the same unstable attribute). Otherwise this uses all of the same infrastructure as `#[rustc_align]`. r? `@traviscross`
2025-09-10interpret: copy_provenance: avoid large intermediate buffer for large repeat ↵Ralf Jung-2/+2
counts
2025-09-09allow `#[rustc_align_static(N)]` on `static`sFolkert de Vries-2/+10
We need a different attribute than `rustc_align` because unstable attributes are tied to their feature (we can't have two unstable features use the same unstable attribute). Otherwise this uses all of the same infrastructure as `#[rustc_align]`.
2025-09-09Auto merge of #145717 - BoxyUwU:erase_regions_rename, r=lcnrbors-3/+4
rename erase_regions to erase_and_anonymize_regions I find it consistently confusing that `erase_regions` does more than replacing regions with `'erased`. it also makes some code look real goofy to be writing manual folders to erase regions with a comment saying "we cant use erase regions" :> or code that re-calls erase_regions on types with regions already erased just to anonymize all the bound regions. r? lcnr idk how i feel about the name being almost twice as long now
2025-09-09erase_regions to erase_and_anonymize_regionsBoxy-3/+4
2025-09-09Rollup merge of #146324 - RalfJung:no-ptr-fragment, r=oli-obkStuart Cook-2/+4
const-eval: disable pointer fragment support This fixes https://github.com/rust-lang/rust/issues/146291 by disabling pointer fragment support for const-eval. I want to properly fix this eventually, but won't get to it in the next few weeks, so this is an emergency patch to prevent the buggy implementation from landing on stable. The beta cutoff is on Sep 12th so if this PR lands after that, we'll need a backport.
2025-09-08fixup limit handling codeJana Dönszelmann-1/+1
2025-09-08const-eval: disable pointer fragment supportRalf Jung-2/+4
2025-09-08Allow static regions in `type_name`.Nicholas Nethercote-2/+3
Fixes #146249.
2025-09-04Rollup merge of #146112 - scrabsha:push-utkysktvulto, r=WaffleLapkinStuart Cook-1/+1
don't uppercase error messages
2025-09-03don't uppercase error messagesSasha Pourcelot-1/+1
a more general version of https://github.com/rust-lang/rust/pull/146080. after a bit of hacking in [`fluent.rs`](https://github.com/rust-lang/rust/blob/master/compiler/rustc_fluent_macro/src/fluent.rs), i discovered that i'm not the only one that is bad at following guidelines :sweat_smile:. this pr lowercases the first letter of all the error messages in the codebase. (i did not change things that are traditionally uppercased such as _MIR_, _ABI_ or _C_) i think it's reasonable to run a `@bors try` so all the test suite is checked, as i cannot run some of the tests on my machine. i double checked (and replaced manually) all the old error messages, but better be safe than sorry. in the future i will try to add a check in `x test tidy` that errors if an error message starts with an uppercase letter.
2025-09-02Revert introduction of `[workspace.dependencies]`.Nicholas Nethercote-3/+3
This was done in #145740 and #145947. It is causing problems for people using r-a on anything that uses the rustc-dev rustup package, e.g. Miri, clippy. This repository has lots of submodules and subtrees and various different projects are carved out of pieces of it. It seems like `[workspace.dependencies]` will just be more trouble than it's worth.
2025-08-28Add `rustc_apfloat` to `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-28Add `either` to `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-27Add `tracing` to `[workspace.dependencies]`.Nicholas Nethercote-1/+1
2025-08-26Rollup merge of #144885 - zachs18:ptr_guaranteed_cmp_more, r=RalfJungStuart Cook-15/+103
Implement some more checks in `ptr_guaranteed_cmp`. * Pointers with different residues modulo their allocations' least common alignment are never equal. * Pointers to the same static allocation are equal if and only if they have the same offset. * Pointers to different non-zero-sized static allocations are unequal if both point within their allocation, and not on opposite ends. Tracking issue for `const_raw_ptr_comparison`: <https://github.com/rust-lang/rust/issues/53020> This should not affect `is_null`, the only usage of this intrinsic on stable. Closes https://github.com/rust-lang/rust/issues/144584
2025-08-23Implement some more checks for `ptr_guaranteed_cmp` in consteval:Zachary S-15/+103
Pointers with different residues modulo their least common allocation alignment are never equal. Pointers to the same static allocation are equal if and only if they have the same offset. Strictly in-bounds (in-bounds and not one-past-the-end) pointers to different static allocations are always unequal. A pointer cannot be equal to an integer if `ptr-int` cannot be null. Also adds more tests for `ptr_guaranteed_cmp`. Co-authored-by: Ralf Jung <post@ralfj.de>
2025-08-22miri: also detect aliasing of in-place argument and return placeRalf Jung-7/+16
2025-08-21Rollup merge of #145700 - nnethercote:fix-145696, r=lcnrJacob Pratt-3/+3
Handle `ReEarlyParam` in `type_name`. Fixes rust-lang/rust#145696. r? `@lcnr`
2025-08-21Handle `ReEarlyParam` in `type_name`.Nicholas Nethercote-3/+3
Fixes #145696.
2025-08-20Rollup merge of #145623 - compiler-errors:pretty-async-name, r=wesleywiserJacob Pratt-1/+30
Pretty print the name of an future from calling async closure Fixes https://github.com/rust-lang/rust/issues/145606 by introducing a way to customize the path rendering of async closures' futures in the pretty printer API.
2025-08-19Pretty print the name of an future from calling async closureMichael Goulet-1/+30
2025-08-19Rollup merge of #145585 - RalfJung:miri-inplace-arg-checks, r=compiler-errors许杰友 Jieyou Xu (Joe)-22/+56
Miri: fix handling of in-place argument and return place handling This fixes two separate bugs (in two separate commits): - If the return place is `_local` and not `*ptr`, we didn't always properly protect it if there were other pointers pointing to that return place. - If two in-place arguments are *the same* local variable, we didn't always detect that aliasing.
2025-08-19Rollup merge of #145306 - Stypox:tracing-misc, r=RalfJung许杰友 Jieyou Xu (Joe)-5/+13
Add tracing to various miscellaneous functions This PR adds tracing to: - `ty.fn_sig()`. There is only one place where `fn_sig` is called for real within `rustc_const_eval`. There are three other places where it's called, but one is inside `ConstCx::fn_sig` (which does not seem to be used anywhere), another is under `if cfg!(debug_assertions)`, and the last is within `call_main` and thus gets called only once. - the two possible things `find_mir_or_eval_fn` can do: "emulate_foreign_item" and "load_mir" - all calls to `Const.eval()` within the Miri or the `rustc_const_eval` codebase. - a separate commit also fixes the style of some tracing macros Those are all quite long-lived operations, that in total make up for 6-7% of the total time spent in the program. I found out about them by looking for long periods of time that were previously not traced at all, using this SQL query in ui.perfetto.dev: ```sql with ordered as (select s1.*, row_number() over (order by s1.ts) as rn from slices as s1 where s1.parent_id is null and s1.dur > 0 and s1.name != "frame" and s1.name != "step" and s1.name != "backtrace") select a.ts+a.dur as ts, b.ts-a.ts-a.dur as dur, a.id, a.track_id, a.category, a.depth, a.stack_id, a.parent_stack_id, a.parent_id, a.arg_set_id, a.thread_ts, a.thread_instruction_count, a.thread_instruction_delta, a.cat, a.slice_id, "empty" as name from ordered as a inner join ordered as b on a.rn=b.rn-1 /*where b.ts-a.ts-a.dur > 5000*/ order by b.ts-a.ts-a.dur desc ``` <details> <summary>How the table was obtained</summary> The above image was obtained in ui.perfetto.dev with the following SQL query after obtaining a trace file by running Miri on the following Rust code with `n=100`. ```sql select "TOTAL PROGRAM DURATION" as name, count(*), max(ts + dur) as "sum(dur)", 100.0 as "%", null as "min(dur)", null as "max(dur)", null as "avg(dur)", null as "stddev(dur)" from slices union select "TOTAL OVER ALL SPANS (excluding events)" as name, count(*), sum(dur), cast(cast(sum(dur) as float) / (select max(ts + dur) from slices) * 1000 as int) / 10.0 as "%", min(dur), max(dur), cast(avg(dur) as int) as "avg(dur)", cast(sqrt(avg(dur*dur)-avg(dur)*avg(dur)) as int) as "stddev(dur)" from slices where parent_id is null and name != "frame" and name != "step" and dur > 0 union select name, count(*), sum(dur), cast(cast(sum(dur) as float) / (select max(ts + dur) from slices) * 1000 as int) / 10.0 as "%", min(dur), max(dur), cast(avg(dur) as int) as "avg(dur)", cast(sqrt(avg(dur*dur)-avg(dur)*avg(dur)) as int) as "stddev(dur)" from slices where parent_id is null and name != "frame" and name != "step" group by name order by sum(dur) desc, count(*) desc ``` ```rust fn main() { let n: usize = std::env::args().nth(1).unwrap().parse().unwrap(); let mut v = (0..n).into_iter().collect::<Vec<_>>(); for i in &mut v { *i += 1; } } ``` </details> <img width="1689" height="317" alt="image" src="https://github.com/user-attachments/assets/ee2c81f5-d74a-4da5-b4b6-ab2770175b14" />
2025-08-19miri: detect passing the same local twice as an in-place argumentRalf Jung-20/+41
2025-08-18Add tracing to various miscellaneous functionsStypox-5/+13
Also use tracing macro syntax instead of format()
2025-08-18interpret: fix in-place return place semantics when the return place ↵Ralf Jung-3/+16
expression is a local variable
2025-08-18interpret: avoid forcing all integer newtypes into memory during ↵Ralf Jung-0/+17
clear_provenance
2025-08-17Auto merge of #145284 - nnethercote:type_name-print-regions, r=lcnrbors-10/+16
Print regions in `type_name`. Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes rust-lang/rust#145168. r? `@lcnr`
2025-08-17Auto merge of #144081 - RalfJung:const-ptr-fragments, r=oli-obkbors-86/+101
const-eval: full support for pointer fragments This fixes https://github.com/rust-lang/const-eval/issues/72 and makes `swap_nonoverlapping` fully work in const-eval by enhancing per-byte provenance tracking with tracking of *which* of the bytes of the pointer this one is. Later, if we see all the same bytes in the exact same order, we can treat it like a whole pointer again without ever risking a leak of the data bytes (that encode the offset into the allocation). This lifts the limitation that was discussed quite a bit in https://github.com/rust-lang/rust/pull/137280. For a concrete piece of code that used to fail and now works properly consider this example doing a byte-for-byte memcpy in const without using intrinsics: ```rust use std::{mem::{self, MaybeUninit}, ptr}; type Byte = MaybeUninit<u8>; const unsafe fn memcpy(dst: *mut Byte, src: *const Byte, n: usize) { let mut i = 0; while i < n { *dst.add(i) = *src.add(i); i += 1; } } const _MEMCPY: () = unsafe { let ptr = &42; let mut ptr2 = ptr::null::<i32>(); // Copy from ptr to ptr2. memcpy(&mut ptr2 as *mut _ as *mut _, &ptr as *const _ as *const _, mem::size_of::<&i32>()); assert!(*ptr2 == 42); }; ``` What makes this code tricky is that pointers are "opaque blobs" in const-eval, we cannot just let people look at the individual bytes since *we don't know what those bytes look like* -- that depends on the absolute address the pointed-to object will be placed at. The code above "breaks apart" a pointer into individual bytes, and then puts them back together in the same order elsewhere. This PR implements the logic to properly track how those individual bytes relate to the original pointer, and to recognize when they are in the right order again. We still reject constants where the final value contains a not-fully-put-together pointer: I have no idea how one could construct an LLVM global where one byte is defined as "the 3rd byte of a pointer to that other global over there" -- and even if LLVM supports this somehow, we can leave implementing that to a future PR. It seems unlikely to me anyone would even want this, but who knows.^^ This also changes the behavior of Miri, by tracking the order of bytes with provenance and only considering a pointer to have valid provenance if all bytes are in the original order again. This is related to https://github.com/rust-lang/unsafe-code-guidelines/issues/558. It means one cannot implement XOR linked lists with strict provenance any more, which is however only of theoretical interest. Practically I am curious if anyone will show up with any code that Miri now complains about - that would be interesting data. Cc `@rust-lang/opsem`
2025-08-16Auto merge of #145304 - m-ou-se:simplify-panic, r=oli-obkbors-4/+4
Revert "Partially outline code inside the panic! macro". This reverts https://github.com/rust-lang/rust/pull/115670 Without any tests/benchmarks that show some improvement, it's hard to know whether the change had any positive effect. (And if it did, whether that effect is still achieved today.)
2025-08-14Print regions in `type_name`.Nicholas Nethercote-10/+16
Currently they are skipped, which is a bit weird, and it sometimes causes malformed output like `Foo<>` and `dyn Bar<, A = u32>`. Most regions are erased by the time `type_name` does its work. So all regions are now printed as `'_` in non-optional places. Not perfect, but better than the status quo. `c_name` is updated to trim lifetimes from MIR pass names, so that the `PASS_NAMES` sanity check still works. It is also renamed as `simplify_pass_type_name` and made non-const, because it doesn't need to be const and the non-const implementation is much shorter. The commit also renames `should_print_region` as `should_print_optional_region`, which makes it clearer that it only applies to some regions. Fixes #145168.