Apply dllimport in ThinLTO
This partially reverts https://github.com/rust-lang/rust/pull/103353 by properly applying `dllimport` if `-Z dylib-lto` is passed. That PR should probably fully be reverted as it looks quite sketchy. We don't know locally if the entire crate graph would be statically linked.
This should hopefully be sufficient to make ThinLTO work for rustc on Windows.
r? ``@wesleywiser``
---
Edit: This PR is changed to just generally revert https://github.com/rust-lang/rust/pull/103353.
Rollup of 12 pull requests
Successful merges:
- #136127 (Allow `*const W<dyn A> -> *const dyn A` ptr cast)
- #136968 (Turn order dependent trait objects future incompat warning into a hard error)
- #137319 (Stabilize `const_vec_string_slice`)
- #137885 (tidy: add triagebot checks)
- #138040 (compiler: Use `size_of` from the prelude instead of imported)
- #138084 (Use workspace lints for crates in `compiler/`)
- #138158 (Move more layouting logic to `rustc_abi`)
- #138160 (depend more on attr_data_structures and move find_attr! there)
- #138192 (crashes: couple more tests)
- #138216 (bootstrap: Fix stack printing when a step cycle is detected)
- #138232 (Reduce verbosity of GCC build log)
- #138242 (Revert "Don't test new error messages with the stage 0 compiler")
r? `@ghost`
`@rustbot` modify labels: rollup
depend more on attr_data_structures and move find_attr! there
r? ``@oli-obk``
This should be an easy one. It just moves some imports around. This is necessary for other changes that I'm working on not to have import cycles. However, it's an easy one to just merge on its own.
Move more layouting logic to `rustc_abi`
Move all `LayoutData`-constructing code to `rustc_abi`:
- Infaillible operations get a new `LayoutData` constructor method;
- Faillible ones get a new method on `LayoutCalculator`.
compiler: Use `size_of` from the prelude instead of imported
Use `std::mem::{size_of, size_of_val, align_of, align_of_val}` from the prelude instead of importing or qualifying them. Apply this change across the compiler.
These functions were added to all preludes in Rust 1.80.
r? ``@compiler-errors``
Change TaskDeps to start preallocated with 128 capacity
This is a tiny change that makes `TaskDeps::read_set` start preallocated with capacity for 128 elements.
From local profiling, it looks like `TaskDeps::read_set` is one of the most-often resized hash-sets in `rustc`.
Don't re-`assume` in `transmute`s that don't change niches
I noticed in nightly 2025-02-21 that `transmute` is emitting way more `assume`s than necessary for newtypes.
For example, the three transmutes in <https://rust.godbolt.org/z/fW1KaTc4o> emits
```rust
define noundef range(i32 1, 0) i32 `@repeatedly_transparent_transmute(i32` noundef range(i32 1, 0) %_1) unnamed_addr {
start:
%0 = sub i32 %_1, 1
%1 = icmp ule i32 %0, -2
call void `@llvm.assume(i1` %1)
%2 = sub i32 %_1, 1
%3 = icmp ule i32 %2, -2
call void `@llvm.assume(i1` %3)
%4 = sub i32 %_1, 1
%5 = icmp ule i32 %4, -2
call void `@llvm.assume(i1` %5)
%6 = sub i32 %_1, 1
%7 = icmp ule i32 %6, -2
call void `@llvm.assume(i1` %7)
%8 = sub i32 %_1, 1
%9 = icmp ule i32 %8, -2
call void `@llvm.assume(i1` %9)
%10 = sub i32 %_1, 1
%11 = icmp ule i32 %10, -2
call void `@llvm.assume(i1` %11)
ret i32 %_1
}
```
But those are all just newtypes that don't change size or niches, so none of it's needed.
After this PR it's down to just
```rust
define noundef range(i32 1, 0) i32 `@repeatedly_transparent_transmute(i32` noundef range(i32 1, 0) %_1) unnamed_addr {
start:
ret i32 %_1
}
```
because none of those `assume`s in the original actually did anything.
(Transmuting to something with a difference niche, though, still has the assumes -- the other tests continue to pass checking that.)
Don't include global asm in `mir_keys`, fix error body synthesis
r? oli-obk
Fixes#137470Fixes#137471Fixes#137472Fixes#137473
try-job: test-various
try-job: x86_64-apple-2
this prevents us from trying unsizing coercion in cases like
`*const W<dyn T>` -> `*const dyn T`, where it would later cause a
compilation error since `W<dyn T>: Sized` and `W<dyn T>: T` do not hold.
On long spans, trim the middle of them to make them fit in the terminal width
When encountering a single line span that is wider than the terminal, we keep context at the start and end of the span but otherwise remove the code from the middle. This is somewhat independent from whether the left and right margins of the output have been trimmed as well.
```
error[E0308]: mismatched types
--> $DIR/long-span.rs:6:15
|
LL | ... = [0, 0, 0, 0, ..., 0, 0];
| ^^^^^^^^^^^^^...^^^^^^^ expected `u8`, found `[{integer}; 1681]`
```
Address part of https://github.com/rust-lang/rust/issues/137680 (missing handling of the long suggestion). Fix https://github.com/rust-lang/rust/issues/125581.
---
Change the way that underline positions are calculated by delaying using the "visual" column position until the last possible moment, instead using the "file"/byte position in the file, and then calculating visual positioning as late as possible. This should make the underlines more resilient to non-1-width unicode chars.
Unfortunately, as part of this change (which fixes some visual bugs) comes with the loss of some eager tab codepoint handling, but the output remains legible despite some minor regression on the "margin trimming" logic.
---
`-Zteach` is perma-unstable, barely used, the highlighting logic buggy and the flag being passed around is tech-debt. We should likely remove `-Zteach` in its entirely.
self-contained linker: conservatively default to `-znostart-stop-gc` on x64 linux
To help stabilization, this PR disables an LLD optimization on x64 linux with respect to `--gc-sections` and encapsulation symbols: it will reduce the number of crates needing to opt-out of lld due to this bfd / lld difference. For example, all the people using [linkme](https://github.com/dtolnay/linkme), which [doesn't work with lld](https://github.com/dtolnay/linkme/issues/63) or on nightly, need to disable lld.
More information about all this, and the historical differences, can be found in:
- https://maskray.me/blog/2021-01-31-metadata-sections-comdat-and-shf-link-order
- https://lld.llvm.org/ELF/start-stop-gc
This optimization has [no visible impact](https://github.com/rust-lang/rust/pull/137685#issuecomment-2686116312) on our benchmarks, so we can use it by default and have a safer/more conservative starting point to remove friction during migration. We can them emit an FCW for the cases where lld detects reliance on encapsulation symbols without `-znostart-stop-gc`, and then revert back to lld's default after a while. No one compiling on nightly relies on this difference, obviously, so doing an FCW is not necessary until after lld is used on stable.
I've tested that this correctly links on `linkme` examples. I've also quickly tried to crate an rmake test but the setup with encapsulation symbols is annoying to reproduce: a few link section/name attributes is not enough, we also need to collect symbols between the encapsulation symbols, without referencing them in code, for `-znostart-stop-gc` to only impact this... It should of course be doable though, maybe ````@Kobzol```` will look into it if they have time.
r? ````@petrochenkov````
Put the alloc unit tests in a separate alloctests package
Same rationale as https://github.com/rust-lang/rust/pull/135937. This PR has some extra complexity though as a decent amount of tests are testing internal implementation details rather than the public api. As such I opted to include the modules containing the types under test using `#[path]` into the alloctests package. This means that those modules still need `#[cfg(test)]`, but the rest of liballoc no longer need it.
Remove i586-pc-windows-msvc
See [MCP 840](https://github.com/rust-lang/compiler-team/issues/840).
I left a specialized error message that should help users that hit this in the wild (for example, because they use it in their CI).
```
error: Error loading target specification: the `i586-pc-windows-msvc` target has been removed. Use the `i686-pc-windows-msvc` target instead.
Windows 10 (the minimum required OS version) requires a CPU baseline of at least i686 so you can safely switch. Run `rustc --print target-list` for a list of built-in targets
```
``@workingjubilee`` ``@calebzulawski`` fyi portable-simd uses this target in CI, if you wanna remove it already before this happens
add a "future" edition
This idea has been discussed previously [on Zulip](https://rust-lang.zulipchat.com/#narrow/channel/213817-t-lang/topic/Continuous.20edition-like.20changes.3F/near/432559262) (though what I've implemented isn't exactly the "next"/"future" editions proposed in that message, just the "future" edition). I've found myself prototyping changes that involve edition migrations and wanting to target an upcoming edition for those migrations, but none exists. This should be permanently unstable and not removed.
compiler: factor Windows x86-32 ABI impl into its own file
While it shares more than zero code with the SysV x86-32 ABI impl, there is no particular reason to organize wildly different ABIs using if-else in the same function.
Add verbatim linker to AIXLinker
This adds support for the "verbatim" native link modifier on AIX, will successfully pass the `native-link-modifier-verbatim-linker test case`
By naming them in `[workspace.lints.rust]` in the top-level
`Cargo.toml`, and then making all `compiler/` crates inherit them with
`[lints] workspace = true`. (I omitted `rustc_codegen_{cranelift,gcc}`,
because they're a bit different.)
The advantages of this over the current approach:
- It uses a standard Cargo feature, rather than special handling in
bootstrap. So, easier to understand, and less likely to get
accidentally broken in the future.
- It works for proc macro crates.
It's a shame it doesn't work for rustc-specific lints, as the comments
explain.
It was added in #129523 to enable building on stable when there were
`cfg(bootstrap)` occurrences in the crate. But those are gone now, so
the section can be removed.
Use `std::mem::{size_of, size_of_val, align_of, align_of_val}` from the
prelude instead of importing or qualifying them.
These functions were added to all preludes in Rust 1.80.
Clean up various LLVM FFI things in codegen_llvm
cc ```@ZuseZ4``` I touched some autodiff parts
The major change of this PR is [bfd88ce](bfd88cead0) which makes `CodegenCx` generic just like `GenericBuilder`
The other commits mostly took advantage of the new feature of making extern functions safe, but also just used some wrappers that were already there and shrunk unsafe blocks.
best reviewed commit-by-commit
Change the way that underline positions are calculated by delaying using
the "visual" column position until the last possible moment, instead
using the "file"/byte position in the file, and then calculating visual
positioning as late as possible. This should make the underlines more
resilient to non-1-width unicode chars.
Unfortunately, as part of this change (which fixes some visual bugs)
comes with the loss of some eager tab codepoint handling, but the output
remains legible despite some minor regression on the "margin trimming"
logic.
When encountering a single line span that is wider than the terminal, we keep context at the start and end of the span but otherwise remove the code from the middle. This is somewhat independent from whether the left and right margins of the output have been trimmed as well.
```
error[E0308]: mismatched types
--> $DIR/long-span.rs:6:15
|
LL | ... = [0, 0, 0, 0, ..., 0, 0];
| ^^^^^^^^^^^^^...^^^^^^^ expected `u8`, found `[{integer}; 1681]`
```
Address part of #137680 (missing handling of the long suggestion). Fix#125581.
`-Zteach` is perma-unstable, barely used, the highlighting logic buggy and the flag being passed around is tech-debt. We should likely remove `-Zteach` in its entirely.
This already works for --emit=metadata, but is possible anytime we're not
linking.
Tests:
`rmeta_bin` checks we're not changing --emit=link (already passes)
`rmeta_bin-pass` tests the new behavior for --emit=obj (would fail today)
and also --emit=metadata which isn't changing
Rollup of 6 pull requests
Successful merges:
- #137674 (Enable `f16` for LoongArch)
- #138034 (library: Use `size_of` from the prelude instead of imported)
- #138060 (Revert #138019 after further discussion about how hir-pretty printing should work)
- #138073 (Break critical edges in inline asm before code generation)
- #138107 (`librustdoc`: clippy fixes)
- #138111 (Use `default_field_values` for `rustc_errors::Context`, `rustc_session::config::NextSolverConfig` and `rustc_session::config::ErrorOutputType`)
r? `@ghost`
`@rustbot` modify labels: rollup
Currently it relies on special treatment of `kw::Empty`, which is really
easy to get wrong. This commit makes the special case clearer in the
type system by using `Option`. It's a bit clumsy, but the synthetic name
handling itself is a bit clumsy; better to make it explicit than sneak
it in.
Fixes#133426.
Use `default_field_values` for `rustc_errors::Context`, `rustc_session::config::NextSolverConfig` and `rustc_session::config::ErrorOutputType`
Wanted to see where `#![feature(default_field_values)]` could be used in the codebase. These three seemed like no-brainers. There are a bunch of more places where we could remove manual `Default` impls, but they `derive` other traits that rely on `syn`, which [doesn't yet support `default_field_values`](https://github.com/dtolnay/syn/issues/1774).
Break critical edges in inline asm before code generation
An inline asm terminator defines outputs along its target edges -- a
fallthrough target and labeled targets. Code generation implements this
by inserting code directly into the target blocks. This approach works
only if the target blocks don't have other predecessors.
Establish required invariant by extending existing code that breaks
critical edges before code generation.
Fixes#137867.
r? ``@bjorn3``
Revert #138019 after further discussion about how hir-pretty printing should work
After some more discussion, #138019 was probably merged a little fast. Though there probably is a real bug in pretty printing, it is not feasible to add similar pretty printing routines for all attributes, and making this specific exception is likely not desired either. For more context, see post-merge comments on #138019
I kept the tests around, but reverted the hir-pretty change.
r? ```@compiler-errors```
Simplify `printf` and shell format suggestions
Simplify tracking `printf` and shell format suggestions. Although allocations could be deferred until after checking that they aren't already in the map, this style is simpler.
In `walk_item`, we call `visit_id` on every item kind. For most of them
we do it directly in `walk_item`. But for `ItemKind::Mod`,
`ItemKind::Enum`, and `ItemKind::Use` we instead do it in the `walk_*`
function called (via the `visit_*` function) from `walk_item`.
I can see no reason for this inconsistency, so this commit makes those
three cases like all the other cases, moving the `visit_id` calls into
`walk_item`. This also avoids the need for a few `HirId` arguments.
This involves replacing `nt_pretty_printing_compatibility_hack` with
`stream_pretty_printing_compatibility_hack`.
The handling of statements in `transcribe` is slightly different to
other nonterminal kinds, due to the lack of `from_ast` implementation
for empty statements.
Notable test changes:
- `tests/ui/proc-macro/expand-to-derive.rs`: the diff looks large but
the only difference is the insertion of a single invisible-delimited
group around a metavar.
Rollup of 17 pull requests
Successful merges:
- #137827 (Add timestamp to unstable feature usage metrics)
- #138041 (bootstrap and compiletest: Use `size_of_val` from the prelude instead of imported)
- #138046 (trim channel value in `get_closest_merge_commit`)
- #138053 (Increase the max. custom try jobs requested to `20`)
- #138061 (triagebot: add a `compiler_leads` ad-hoc group)
- #138064 (Remove - from xtensa targets cpu names)
- #138075 (Use final path segment for diagnostic)
- #138078 (Reduce the noise of bootstrap changelog warnings in --dry-run mode)
- #138081 (Move `yield` expressions behind their own feature gate)
- #138090 (`librustdoc`: flatten nested ifs)
- #138092 (Re-add `DynSend` and `DynSync` impls for `TyCtxt`)
- #138094 (a small borrowck cleanup)
- #138098 (Stabilize feature `const_copy_from_slice`)
- #138103 (Git ignore citool's target directory)
- #138105 (Fix broken link to Miri intrinsics in documentation)
- #138108 (Mention me (WaffleLapkin) when changes to `rustc_codegen_ssa` occur)
- #138117 ([llvm/PassWrapper] use `size_t` when building arg strings)
r? `@ghost`
`@rustbot` modify labels: rollup
Rollup of 25 pull requests
Successful merges:
- #135733 (Implement `&pin const self` and `&pin mut self` sugars)
- #135895 (Document workings of successors more clearly)
- #136922 (Pattern types: Avoid having to handle an Option for range ends in the type system or the HIR)
- #137303 (Remove `MaybeForgetReturn` suggestion)
- #137327 (Undeprecate env::home_dir)
- #137358 (Match Ergonomics 2024: add context and examples to the unstable book)
- #137534 ([rustdoc] hide item that is not marked as doc(inline) and whose src is doc(hidden))
- #137565 (Try to point of macro expansion from resolver and method errors if it involves macro var)
- #137637 (Check dyn flavor before registering upcast goal on wide pointer cast in MIR typeck)
- #137643 (Add DWARF test case for non-C-like `repr128` enums)
- #137744 (Re-add `Clone`-derive on `Thir`)
- #137758 (fix usage of ty decl macro fragments in attributes)
- #137764 (Ensure that negative auto impls are always applicable)
- #137772 (Fix char count in `Display` for `ByteStr`)
- #137798 (ci: use ubuntu 24 on arm large runner)
- #137802 (miri native-call support: all previously exposed provenance is accessible to the callee)
- #137805 (adjust Layout debug printing to match the internal field name)
- #137808 (Do not require that unsafe fields lack drop glue)
- #137820 (Clarify why InhabitedPredicate::instantiate_opt exists)
- #137825 (Provide more context on resolve error caused from incorrect RTN)
- #137834 (rustc_fluent_macro: use CARGO_CRATE_NAME instead of CARGO_PKG_NAME)
- #137868 (Add minimal platform support documentation for powerpc-unknown-linux-gnuspe)
- #137910 (Improve error message for `AsyncFn` trait failure for RPIT)
- #137920 (interpret/provenance_map: consistently use range_is_empty)
- #138038 (Update `compiler-builtins` to 0.1.151)
r? `@ghost`
`@rustbot` modify labels: rollup
[llvm/PassWrapper] use `size_t` when building arg strings
While we're unlikely to ever overflow `int` in this case, it's still more proper to use `size_t` consistently when dealing with buffer lengths. If nothing else, this fixes a few `-Wsign-compare` warnings.
Re-add `DynSend` and `DynSync` impls for `TyCtxt`
They were somewhat unexpectedly removed in #136731. This PR adds them back, as requested in https://github.com/rust-lang/rust/pull/136731#issuecomment-2702504644. I've also tried to expand the comments a bit to make it less likely that they're removed again in the future.
r? `@SparrowLii`
Move `yield` expressions behind their own feature gate
In order to make progress with the `iter!` macro (e.g. in #137725), we need `yield` expressions to be available without the `coroutines` feature. This PR moves `yield` to be guarded by the `yield_expr` feature so that we can stabilize that independently (or at least, concurrently with the `iter_macro` feature). Note that once `yield` is stable, it will still be an error to use `yield` expressions outside something like a generator or coroutine, and these features remain unstable.
r? `@oli-obk`
Use final path segment for diagnostic
Test changes should prove the effect of this PR; we want to mention the *function name* not the arbitrary first segment of the path.
Add timestamp to unstable feature usage metrics
part of https://github.com/rust-lang/rust/issues/129485
with this we should be able to temporarily enable metrics on docs.rs to gather a nice test dataset for the initial PoC dashboard
r? ```@estebank```
An inline asm terminator defines outputs along its target edges -- a
fallthrough target and labeled targets. Code generation implements this
by inserting code directly into the target blocks. This approach works
only if the target blocks don't have other predecessors.
Establish required invariant by extending existing code that breaks
critical edges before code generation.
interpret/provenance_map: consistently use range_is_empty
https://github.com/rust-lang/rust/pull/137704 started using this for per-ptr provenance; let's be consistent and use it also for the per-byte provenance check. Also rename the methods to avoid having both "get" and "is_empty" in the name.
r? ````@oli-obk````
Improve error message for `AsyncFn` trait failure for RPIT
Use a `WellFormedDerived` obligation cause to make sure we can turn an `AsyncFnKindHelper` trait goal into its parent `AsyncFn*` goal, then fix the logic for reporting `AsyncFn*` kind mismatches.
Best reviewed without whitespace.
Fixes#137905
r? oli-obk
Provide more context on resolve error caused from incorrect RTN
When encountering a resolve E0575 error for an associated method (when a type was expected), see if it could have been an intended return type notation bound.
```
error[E0575]: expected associated type, found associated function `Trait::method`
--> $DIR/bad-inputs-and-output.rs:31:36
|
LL | fn foo_qualified<T: Trait>() where <T as Trait>::method(i32): Send {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^ not a associated type
|
help: you might have meant to use the return type notation syntax
|
LL - fn foo_qualified<T: Trait>() where <T as Trait>::method(i32): Send {}
LL + fn foo_qualified<T: Trait>() where T::method(..): Send {}
|
```
Built on top of #137824, only second commit is relevant for review.
r? ````````@compiler-errors````````
Clarify why InhabitedPredicate::instantiate_opt exists
At first glance, the extra casework seems pointless and needlessly error-prone. Clarify that there is a reason for it being there.
miri native-call support: all previously exposed provenance is accessible to the callee
When Miri invokes a native C function, the memory C can access needs to be "prepared": to avoid false positives, we need to consider all that memory initialized, and we need to consider it to have arbitrary provenance. So far we did this for all pointers passed to C, but not for pointers that were exposed already before the native call. This PR adjusts the logic so that we now "prepare" all memory that has ever been exposed.
This fixes cases such as:
- cast a pointer to integer, send that integer to C, and access the memory there (`test_pass_ptr_as_int`)
- send a pointer to some memory to C, which stores it somewhere; then in Rust store another pointer in that memory, and access that via C (`test_pass_ptr_via_previously_shared_mem`)
r? `````@oli-obk`````
fix usage of ty decl macro fragments in attributes
See the test case. Due to one missing code path (and also the changes in #137517), using $ty or other specific fragments as part of an attr wouldn't work. $tt used to work since it wouldn't be parsed anywhere along the way.
Closes#137662
Re-add `Clone`-derive on `Thir`
This PR adds back `Clone` for `Thir`.
If a tool wants to access a `thir_body` query result in the `Callbacks::after_analysis` hook, it can't do so (I think) without a `Clone` impl on `Thir`, because `check_unsafety` steals the value. With `Clone`, the `thir_body` query provider can be overriden to cache a clone of the `Thir`, circumventing that issue.
Specifically, we need it for https://github.com/rust-corpus/qrates, [here](ca7a230196/extractor/src/lib.rs (L205)).
Please let me know if there are issues with this PR/if there's another way to solve the problem at hand
Try to point of macro expansion from resolver and method errors if it involves macro var
In the case that a macro caller passes an identifier into a macro generating a path or method expression, point out that identifier in the context of the *macro* so it's a bit more clear how the macro is involved in causing the error.
r? ``````````@estebank`````````` or reassign
Remove `MaybeForgetReturn` suggestion
#115196 implemented a suggestion to add a missing `return` when there is an ambiguity error, when that ambiguity error could be constrained by the return type of the function.
I initially reviewed it and thought it could be useful; however, looking back at that code now, I feel like it's a bit too much of a hack to be worth keeping around in typeck, especially given how rare it's expected to fire in practice. This is especially true because it depends on `StashKey::MaybeForgetReturn`, which is only stashed when we have *Sized* obligation ambiguity errors. Let's remove it for now.
I'd like to note that it's basically impossible to get this suggestion to apply in its current state except for what I'd consider somewhat artificial examples, involving no generic trait bounds. For example, it's not triggered for:
```rust
struct W<T>(T);
fn bar<T: Default>() -> W<T> { todo!() }
fn foo() -> W<i32> {
if true {
bar();
}
W(0)
}
```
Nor is it triggered for:
```
fn foo() -> i32 {
if true {
Default::default();
}
0
}
```
It's basically only triggered iff there's only one ambiguity error on the type, which is `Sized`.
Generally, suggesting something that affects control flow is a pretty dramatic suggestion; therefore, both the accuracy and precision of this diagnostic should be pretty high.
One other, somewhat unrelated observation is that this might be using stashed diagnostics incorrectly (or at least unnecessarily). Stashed diagnostics are used when error detection is fragmented over several major stages of the compiler, like a parse or resolver error which later can be recovered in typeck. However, this one is a bit different since it is fully handled within typeck -- perhaps that suggests that if this were to be reimplemented, it wouldn't need to be so complicated of an implementation.
Pattern types: Avoid having to handle an Option for range ends in the type system or the HIR
Instead,
1. during hir_ty_lowering, we now generate constants for the min/max when the range doesn't have a start/end specified.
2. in a later commit we generate those constants during ast lowering, simplifying everything further by not having to handle the range end inclusivity anymore in the type system (and thus avoiding any issues of `0..5` being different from `0..=4`
I think it makes all the type system code simpler, and the cost of the extra `ConstKind::Value` processing seems negligible.
r? `@BoxyUwU`
cc `@joshtriplett` `@scottmcm`
Implement `&pin const self` and `&pin mut self` sugars
This PR implements part of #130494.
It introduces the sugars `&pin const self` and `&pin mut self` for `self: Pin<&Self>` and `self: Pin<&mut Self>`.
Avoid allocating a vector of small vectors merely to determine how many
predecessors each basic block has.
Additionally use u8 and saturating operations. The pass only needs to
distinguish between [0..1] and [2..].
While it shares more than zero code with the SysV x86-32 ABI impl,
there is no particular reason to organize wildly different ABIs
using if-else in the same function.
Inline `FnOnce`/`FnMut`/`Fn` shims once again
This PR fixes the argument checking for `extern "rust-call"` ABI functions with a spread arg, which do no expect their arguments to be exploded from a tuple like closures do.
Secondly, it removes the hack that prevented them from being inlined. This results in more work done by the compiler, but it does end up allowing us to inline functions we didn't before.
Fixes#137901
compiler: add `ExternAbi::is_rustic_abi`
Various parts of the compiler were hand-rolling this extremely simple check that is nonetheless easy to get wrong as the compiler evolves over time. Discourage them from being so "original" again by replacing it with a single implementation on the type that represents these ABIs. This simplifies a surprising amount of code as a result.
Also fixes#132981, an ICE that emerged due to other checks being made stricter.
mir_build: Integrate "simplification" steps into match-pair-tree creation
The “simplification” step helps to prepare THIR patterns for lowering into MIR, and originally dates back to the earliest days of MIR in the compiler.
Over time, various intermediate data structures have been introduced (e.g. `MatchPair`, later renamed to `MatchPairTree`) that reduce the need for a separate simplification step, because some of the necessary simplifications can be built into the construction of those intermediate structures instead. This PR continues that process to its logical conclusion and removes the simplification step entirely, by integrating its remaining responsibilities into match-pair-tree creation: flattening “irrefutable” nodes, collecting bindings/ascriptions in flat lists, and sorting or-patterns after other subpatterns.
This has a few immediate benefits:
- We can remove `TestCase::Irrefutable`, which was not allowed to exist after simplification, and was much larger than other test-case variants.
- We can make `MatchPairTree::place` non-optional, because only irrefutable nodes could fail to have a place.
In the future, this should also help with some ideas I have for simplifying how `AscribeUserType` and `ExpandedConstant` nodes are handled, by representing them as side-data keyed by THIR pattern ID, so that they are no longer their own kinds of THIR pattern node.
Resume one waiter at once in deadlock handler
When multiple query loop errors occur in the code, only one waiter should be resumed at a time to avoid waking up multiple waiters at the same time and causing deadlock due to thread grabbing.
This fixes the UI failures in #132051
cc `@Zoxc` `@cjgillot` `@nnethercote` `@bjorn3` `@Kobzol`
Zulip discussion [here](https://rust-lang.zulipchat.com/#narrow/channel/187679-t-compiler.2Fwg-parallel-rustc/topic/Deadlocks.20and.20Rayon)
Edit: We can't reproduce these bugs with the existing test suits, so we keep them until we merge #132051
UPDATES #129912
UPDATES #120757
UPDATES #129911
Only use implied bounds hack if bevy, and use deeply normalize in implied bounds hack
Consolidates the implied bounds computation mode into a single function, which deeply normalizes, and if it's in **compat** mode (for bevy), it extracts outlives bounds from the infcx.
Previously, we were using the implied bounds compat mode in two cases:
1. During WF, if it detects `ParamSet`
2. EVERYWHERE ELSE (lol) -- e.g. borrowck, predicate entailment, etc.
While I think this is fine, and the net effect was just that we emitted fewer diagnostics, it makes me uncomfortable that all crates were using the supposed "compat" code.
Fixes#137767
Make `ptr_cast_add_auto_to_object` lint into hard error
In Rust 1.81, we added a FCW lint (including linting in dependencies) against pointer casts that add an auto trait to dyn bounds. This was part of work making casts of pointers involving trait objects stricter, and was part of the work needed to restabilize trait upcasting.
We considered just making this a hard error, but opted against it at that time due to breakage found by crater. This breakage was mostly due to the `anymap` crate which has been a persistent problem for us.
It's now a year later, and the fact that this is not yet a hard error is giving us pause about stabilizing arbitrary self types and `derive(CoercePointee)`. So let's see about making a hard error of this.
r? ghost
cc ```@adetaylor``` ```@Darksonn``` ```@BoxyUwU``` ```@RalfJung``` ```@compiler-errors``` ```@oli-obk``` ```@WaffleLapkin```
Related:
- https://github.com/rust-lang/rust/pull/135881
- https://github.com/rust-lang/rust/issues/136702
- https://github.com/rust-lang/rust/pull/136776
Tracking:
- https://github.com/rust-lang/rust/issues/127323
- https://github.com/rust-lang/rust/issues/44874
- https://github.com/rust-lang/rust/issues/123430
Make CrateItem::body() function return an option
When we initially created `CrateItem`, it would only represent items that contain a body.
That is no longer the case, for now, make this explicit by expanding the APIs to retrieve the item body.
This is related to https://github.com/rust-lang/project-stable-mir/issues/34
r? `@oli-obk`
Pretty-print `#[deprecated]` attribute in HIR.
Pretty-print `#[deprecated]` attribute in a form closer to how it might appear in Rust source code, rather than using a `Debug`-like representation.
Consider the following Rust code:
```rust
#[deprecated]
pub struct PlainDeprecated;
#[deprecated = "here's why this is deprecated"]
pub struct DirectNote;
#[deprecated(since = "1.2.3", note = "here's why this is deprecated")]
pub struct SinceAndNote;
```
Here's the previous output:
```
#[attr="Deprecation{deprecation: Deprecation{since: Unspecifiednote:
suggestion: }span: }")]
struct PlainDeprecated;
#[attr="Deprecation{deprecation: Deprecation{since: Unspecifiednote:
here's why this is deprecatedsuggestion: }span: }")]
struct DirectNote;
#[attr="Deprecation{deprecation: Deprecation{since: NonStandard(1.2.3)note:
here's why this is deprecatedsuggestion: }span: }")]
struct SinceAndNote;
```
Here's the new output:
```rust
#[deprecated]
struct PlainDeprecated;
#[deprecated = "here's why this is deprecated"]
struct DirectNote;
#[deprecated(since = "1.2.3", note = "here's why this is deprecated"]
struct SinceAndNote;
```
Also includes a test for `#[diagnostic::(..)]` attributes, though their behavior is not changed here. I already wrote the test, so I figured it probably won't hurt to have it.
Related to discussion in #137645.
r? `@jdonszelmann`
Remove unused `PpMode::needs_hir`
This method was added in #99360 to avoid an overzealous `span_delayed_bug` ICE in specific circumstances, but the only caller was subsequently removed in #136603, which presumably avoids the problem in a more principled way.
Simplify `<Postorder as Iterator>::size_hint`
The current version is sometimes malformed (cc #137919); let's see if we can get away with a loose but trivially-correct one.
Allow struct field default values to reference struct's generics
Right now, the default field value feature (https://github.com/rust-lang/rust/issues/132162) lowers anon consts whose types may reference ADT params that the const doesn't inherit.
This PR fixes this, so that these defaults can reference ADTs' generics, and sets the `generics_of` parenting up correctly.
There doesn't seem to be a good reason not to support this, since the anon const has a well-defined type from the field, and the anon const doesn't interact with the type system like generic parameter defaults do.
r? `````@boxyuwu````` or reassign
I could also make this into an error if this seems problematic (https://github.com/rust-lang/rust/compare/master...compiler-errors:rust:default-field-value-implicit-param?expand=1)...... but I'd rather make this work and register an open question on the tracking issue about validating that this is well-vetted.
Fixes#137896
Do not recover missing lifetime with random in-scope lifetime
Suppresses a ton of stray errors, since this recovery doesn't really make sense anymore now that we have a dedicated `ReError` kind.
r? oli-obk or reassign
When we initially created `CrateItem`, it would only represent items
that contain a body.
That is no longer the case, for now, make this explicit by expanding
the APIs to retrieve the item body.
This is related to https://github.com/rust-lang/project-stable-mir/issues/34
Update `compiler-builtins` to 0.1.149
Includes a change to make a subset of math symbols available on all platforms [1], and disables `f16` on aarch64 without neon [2].
[1]: https://github.com/rust-lang/compiler-builtins/pull/763
[2]: https://github.com/rust-lang/compiler-builtins/pull/775
try-job: aarch64-gnu
try-job: aarch64-gnu-debug
try-job: armhf-gnu
try-job: dist-various-1
try-job: dist-various-2
try-job: dist-aarch64-linux
try-job: dist-arm-linux
try-job: dist-armv7-linux
try-job: dist-x86_64-linux
try-job: test-various
Currently it is called twice, once with `allow_unstable` set to true and
once with it set to false. This results in some duplicated work. Most
notably, for the LLVM backend, `LLVMRustHasFeature` is called twice for
every feature, and it's moderately slow. For very short running
compilations on platforms with many features (e.g. a `check` build of
hello-world on x86) this is a significant fraction of runtime.
This commit changes `target_features_cfg` so it is only called once, and
it now returns a pair of feature sets. This halves the number of
`LLVMRustHasFeature` calls.
mgca: Lower all const paths as `ConstArgKind::Path`
When `#![feature(min_generic_const_args)]` is enabled, we now lower all
const paths in generic arg position to `hir::ConstArgKind::Path`. We
then lower assoc const paths to `ty::ConstKind::Unevaluated` since we
can no longer use the anon const expression lowering machinery. In the
process of implementing this, I factored out `hir_ty_lowering` code that
is now shared between lowering assoc types and assoc consts.
This PR also introduces a `#[type_const]` attribute for trait assoc
consts that are allowed as const args. However, we still need to
implement code to check that assoc const definitions satisfy
`#[type_const]` if present (basically is it a const path or a
monomorphic anon const).
r? `@BoxyUwU`
Support raw-dylib link kind on ELF
raw-dylib is a link kind that allows rustc to link against a library without having any library files present.
This currently only exists on Windows. rustc will take all the symbols from raw-dylib link blocks and put them in an import library, where they can then be resolved by the linker.
While import libraries don't exist on ELF, it would still be convenient to have this same functionality. Not having the libraries present at build-time can be convenient for several reasons, especially cross-compilation. With raw-dylib, code linking against a library can be cross-compiled without needing to have these libraries available on the build machine. If the libc crate makes use of this, it would allow cross-compilation without having any libc available on the build machine. This is not yet possible with this implementation, at least against libc's like glibc that use symbol versioning. The raw-dylib kind could be extended with support for symbol versioning in the future.
This implementation is very experimental and I have not tested it very well. I have tested it for a toy example and the lz4-sys crate, where it was able to successfully link a binary despite not having a corresponding library at build-time.
I was inspired by Björn's comments in https://internals.rust-lang.org/t/bundle-zig-cc-in-rustup-by-default/22096/27
Tracking issue: #135694
r? bjorn3
try-job: aarch64-apple
try-job: x86_64-msvc-1
try-job: x86_64-msvc-2
try-job: test-various
When `#![feature(min_generic_const_args)]` is enabled, we now lower all
const paths in generic arg position to `hir::ConstArgKind::Path`. We
then lower assoc const paths to `ty::ConstKind::Unevaluated` since we
can no longer use the anon const expression lowering machinery. In the
process of implementing this, I factored out `hir_ty_lowering` code that
is now shared between lowering assoc types and assoc consts.
This PR also introduces a `#[type_const]` attribute for trait assoc
consts that are allowed as const args. However, we still need to
implement code to check that assoc const definitions satisfy
`#[type_const]` if present (basically is it a const path or a
monomorphic anon const).
