Introduce `ConstAllocation`.
Currently some `Allocation`s are interned, some are not, and it's very
hard to tell at a use point which is which.
This commit introduces `ConstAllocation` for the known-interned ones,
which makes the division much clearer. `ConstAllocation::inner()` is
used to get the underlying `Allocation`.
In some places it's natural to use an `Allocation`, in some it's natural
to use a `ConstAllocation`, and in some places there's no clear choice.
I've tried to make things look as nice as possible, while generally
favouring `ConstAllocation`, which is the type that embodies more
information. This does require quite a few calls to `inner()`.
The commit also tweaks how `PartialOrd` works for `Interned`. The
previous code was too clever by half, building on `T: Ord` to make the
code shorter. That caused problems with deriving `PartialOrd` and `Ord`
for `ConstAllocation`, so I changed it to build on `T: PartialOrd`,
which is slightly more verbose but much more standard and avoided the
problems.
r? `@fee1-dead`
Currently some `Allocation`s are interned, some are not, and it's very
hard to tell at a use point which is which.
This commit introduces `ConstAllocation` for the known-interned ones,
which makes the division much clearer. `ConstAllocation::inner()` is
used to get the underlying `Allocation`.
In some places it's natural to use an `Allocation`, in some it's natural
to use a `ConstAllocation`, and in some places there's no clear choice.
I've tried to make things look as nice as possible, while generally
favouring `ConstAllocation`, which is the type that embodies more
information. This does require quite a few calls to `inner()`.
The commit also tweaks how `PartialOrd` works for `Interned`. The
previous code was too clever by half, building on `T: Ord` to make the
code shorter. That caused problems with deriving `PartialOrd` and `Ord`
for `ConstAllocation`, so I changed it to build on `T: PartialOrd`,
which is slightly more verbose but much more standard and avoided the
problems.
explain why shift with signed offset works the way it does
I was worried for a bit here that Miri/CTFE would be inconsistent with codegen, but I *think* everything is all right, actually.
Cc `@oli-obk` `@eddyb`
Always include global target features in function attributes
This ensures that information about target features configured with
`-C target-feature=...` or detected with `-C target-cpu=native` is
retained for subsequent consumers of LLVM bitcode.
This is crucial for linker plugin LTO, since this information is not
conveyed to the plugin otherwise.
<details><summary>Additional test case demonstrating the issue</summary>
```rust
extern crate core;
#[inline]
#[target_feature(enable = "aes")]
unsafe fn f(a: u128, b: u128) -> u128 {
use core::arch::x86_64::*;
use core::mem::transmute;
transmute(_mm_aesenc_si128(transmute(a), transmute(b)))
}
pub fn g(a: u128, b: u128) -> u128 {
unsafe { f(a, b) }
}
fn main() {
let mut args = std::env::args();
let _ = args.next().unwrap();
let a: u128 = args.next().unwrap().parse().unwrap();
let b: u128 = args.next().unwrap().parse().unwrap();
println!("{}", g(a, b));
}
```
```console
$ rustc --edition=2021 a.rs -Clinker-plugin-lto -Clink-arg=-fuse-ld=lld -Ctarget-feature=+aes -O
...
= note: LLVM ERROR: Cannot select: intrinsic %llvm.x86.aesni.aesenc
```
</details>
r? `@nagisa`
add address sanitizer fo android
We have been being using asan to debug the rust/cpp/c mixed android application in production for months: recompile the rust library with a patched rustc, everything just works fine. The patch is really small thanks to `@nagisa` 's refactoring in https://github.com/rust-lang/rust/pull/81866
r? `@nagisa`
The majority of the code is only used by either rustbuild or
rustc_llvm's build script. Rust_build is compiled once for rustbuild and
once for every stage. This means that the majority of the code in this
crate is needlessly compiled multiple times. By moving only the code
actually used by the respective crates to rustbuild and rustc_llvm's
build script, this needless duplicate compilation is avoided.
Reenable generator drop tracking tests and fix mutation handling
The previous PR, #94068, was overly zealous in counting mutations as borrows, which effectively nullified drop tracking. We would have caught this except the drop tracking tests were still ignored, despite having the option of using the `-Zdrop-tracking` flag now.
This PR fixes the issue introduced by #94068 by only counting mutations as borrows the mutated place has a project. This is sufficient to distinguish `x.y = 42` (which should count as a borrow of `x`) from `x = 42` (which is not a borrow of `x` because the whole variable is overwritten).
This PR also re-enables the drop tracking regression tests using the `-Zdrop-tracking` flag so we will avoid introducing these sorts of issues in the future.
Thanks to ``@tmiasko`` for noticing this problem and pointing it out!
r? ``@tmiasko``
Do not point at whole file missing `fn main`
Only point at the end of the crate. We could try making it point at the
beginning of the crate, but that is confused with `DUMMY_SP`, causing
the output to be *worse*.
This change will make it so that VSCode will *not* underline the whole
file when `main` is missing, so other errors will be visible.
Only point at the end of the crate. We could try making it point at the
beginning of the crate, but that is confused with `DUMMY_SP`, causing
the output to be *worse*.
This change will make it so that VSCode will *not* underline the whole
file when `main` is missing, so other errors will be visible.
Rollup of 5 pull requests
Successful merges:
- #94362 (Add well known values to `--check-cfg` implementation)
- #94577 (only disable SIMD for doctests in Miri (not for the stdlib build itself))
- #94595 (Fix invalid `unresolved imports` errors for a single-segment import)
- #94596 (Delay bug in expr adjustment when check_expr is called multiple times)
- #94618 (Don't round stack size up for created threads in Windows)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Delay bug in expr adjustment when check_expr is called multiple times
Instead of including slightly more complicated logic in `check_argument_types` to fix the bug (#94516) I introduced in #94438, and inevitably have this bug appear once again when some other diagnostic is written that causes `check_expr` to be called an expression during a (bad) code path, just delay the bug in adjustment logic.
I am open to other implementations that don't delay the bug here.
Fixes#94516
Add well known values to `--check-cfg` implementation
This pull-request adds well known values for the well known names via `--check-cfg=values()`.
[RFC 3013: Checking conditional compilation at compile time](https://rust-lang.github.io/rfcs/3013-conditional-compilation-checking.html#checking-conditional-compilation-at-compile-time) doesn't define this at all, but this seems a nice improvement.
The activation is done by a empty `values()` (new syntax) similar to `names()` except that `names(foo)` also activate well known names while `values(aa, "aa", "kk")` would not.
As stated this use a different activation logic because well known values for the well known names are not always sufficient.
In fact this is problematic for every `target_*` cfg because of non builtin targets, as the current implementation use those built-ins targets to create the list the well known values.
The implementation is straight forward, first we gather (if necessary) all the values (lazily or not) and then we apply them.
r? ```@petrochenkov```
Enable conditional compilation checking on the Rust codebase
This pull-request enable conditional compilation checking on every rust project build by the `bootstrap` tool.
To be more specific, this PR only enable well known names checking + extra names (bootstrap, parallel_compiler, ...).
r? `@Mark-Simulacrum`
Remove num_cpus dependency from bootstrap, build-manifest and rustc_s…
…ession
`std::threads::available_parallelism` was stabilized in rust 1.59.
r? ```````````````````````````@Mark-Simulacrum```````````````````````````
This ensures that information about target features configured with
`-C target-feature=...` or detected with `-C target-cpu=native` is
retained for subsequent consumers of LLVM bitcode.
This is crucial for linker plugin LTO, since this information is not
conveyed to the plugin otherwise.
Add !align metadata on loads of &/&mut/Box
Note that this refers to the alignment of what the loaded value points
to, _not_ the alignment of the loaded value itself.
r? `@ghost` (blocked on #94158)
Ensure stability directives are checked in all cases
Split off #93017
Stability and deprecation were not checked in all cases, for instance if a type error happened.
This PR moves the check earlier in the pipeline to ensure the errors are emitted in all cases.
r? `@lcnr`
Make Ord and PartialOrd opt-out in `newtype_index`
Part of work on #90317. This will allow us to do
```diff
rustc_index::newtype_index! {
/// A unique ID associated with a macro invocation and expansion.
pub struct LocalExpnId {
ENCODABLE = custom
DEBUG_FORMAT = "expn{}"
+ ORD_IMPL = off
}
}
```
ARM: Only allow using d16-d31 with asm! when supported by the target
Support can be determined by checking for the "d32" LLVM feature.
r? ```````````````@nagisa```````````````
Generalize get_nullable_type to accept types that have an all-ones bit
pattern as their sentry "null" value.
This will allow [`OwnedFd`], [`BorrowedFd`], [`OwnedSocket`], and
[`BorrowedSocket`] to be marked with
`#[rustc_nonnull_optimization_guaranteed]`, which will allow
`Option<OwnedFd>`, `Option<BorrowedFd>`, `Option<OwnedSocket>`, and
`Option<BorrowedSocket>` to be used in FFI declarations, as described
in the [I/O safety RFC].
For example, it will allow a function like `open` on Unix and `WSASocketW`
on Windows to be declared using `Option<OwnedFd>` and `Option<OwnedSocket>`
return types, respectively.
The actual change to add `#[rustc_nonnull_optimization_guaranteed]`
to the abovementioned types will be a separate PR, as it'll depend on
having this patch in the stage0 compiler.
Also, update the diagnostics to mention that "niche optimizations" are
used in libstd as well as libcore, as `rustc_layout_scalar_valid_range_start`
and `rustc_layout_scalar_valid_range_end` are already in use in libstd.
[`OwnedFd`]: c9dc44be24/library/std/src/os/fd/owned.rs (L49)
[`BorrowedFd`]: c9dc44be24/library/std/src/os/fd/owned.rs (L29)
[`OwnedSocket`]: c9dc44be24/library/std/src/os/windows/io/socket.rs (L51)
[`BorrowedSocket`]: c9dc44be24/library/std/src/os/windows/io/socket.rs (L29)
[I/O safety RFC]: https://github.com/rust-lang/rfcs/blob/master/text/3128-io-safety.md#ownedfd-and-borrowedfdfd-1
Fix invalid lint_node_id being put on a removed stmt
This pull-request remove a invalid `assign_id!` being put on an stmt node.
The problem is that this node is being removed away by a cfg making it unreachable when triggering a buffered lint.
The comment in the other match arm already tell to not assign a id because it could have a `#[cfg()]` so this is just respecting the comment.
Fixes https://github.com/rust-lang/rust/issues/94523
r? ```````@petrochenkov```````
improve comments for `simplify_type`
Should now correctly describe what's going on. Experimented with checking the invariant for projections
but that ended up requiring fairly involved changes. I assume that it is not possible to get unsoundness here,
at least for now and I can pretty much guarantee that it's impossible to trigger it by accident.
r? `````@nikomatsakis````` cc #92721
Implementation of the `expect` attribute (RFC 2383)
This is an implementation of the `expect` attribute as described in [RFC-2383](https://rust-lang.github.io/rfcs/2383-lint-reasons.html). The attribute allows the suppression of lint message by expecting them. Unfulfilled lint expectations (meaning no expected lint was caught) will emit the `unfulfilled_lint_expectations` lint at the `expect` attribute.
### Example
#### input
```rs
// required feature flag
#![feature(lint_reasons)]
#[expect(unused_mut)] // Will warn about an unfulfilled expectation
#[expect(unused_variables)] // Will be fulfilled by x
fn main() {
let x = 0;
}
```
#### output
```txt
warning: this lint expectation is unfulfilled
--> $DIR/trigger_lint.rs:3:1
|
LL | #[expect(unused_mut)] // Will warn about an unfulfilled expectation
| ^^^^^^^^^^
|
= note: `#[warn(unfulfilled_lint_expectations)]` on by default
```
### Implementation
This implementation introduces `Expect` as a new lint level for diagnostics, which have been expected. All lint expectations marked via the `expect` attribute are collected in the [`LintLevelsBuilder`] and assigned an ID that is stored in the new lint level. The `LintLevelsBuilder` stores all found expectations and the data needed to emit the `unfulfilled_lint_expectations` in the [`LintLevelsMap`] which is the result of the [`lint_levels()`] query.
The [`rustc_errors::HandlerInner`] is the central error handler in rustc and handles the emission of all diagnostics. Lint message with the level `Expect` are suppressed during this emission, while the expectation ID is stored in a set which marks them as fulfilled. The last step is then so simply check if all expectations collected by the [`LintLevelsBuilder`] in the [`LintLevelsMap`] have been marked as fulfilled in the [`rustc_errors::HandlerInner`]. Otherwise, a new lint message will be emitted.
The implementation of the `LintExpectationId` required some special handling to make it stable between sessions. Lints can be emitted during [`EarlyLintPass`]es. At this stage, it's not possible to create a stable identifier. The level instead stores an unstable identifier, which is later converted to a stable `LintExpectationId`.
### Followup TO-DOs
All open TO-DOs have been marked with `FIXME` comments in the code. This is the combined list of them:
* [ ] The current implementation doesn't cover cases where the `unfulfilled_lint_expectations` lint is actually expected by another `expect` attribute.
* This should be easily possible, but I wanted to get some feedback before putting more work into this.
* This could also be done in a new PR to not add to much more code to this one
* [ ] Update unstable documentation to reflect this change.
* [ ] Update unstable expectation ids in [`HandlerInner::stashed_diagnostics`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_errors/struct.HandlerInner.html#structfield.stashed_diagnostics)
### Open questions
I also have a few open questions where I would like to get feedback on:
1. The RFC discussion included a suggestion to change the `expect` attribute to something else. (Initiated by `@Ixrec` [here](https://github.com/rust-lang/rfcs/pull/2383#issuecomment-378424091), suggestion from `@scottmcm` to use `#[should_lint(...)]` [here](https://github.com/rust-lang/rfcs/pull/2383#issuecomment-378648877)). No real conclusion was drawn on that point from my understanding. Is this still open for discussion, or was this discarded with the merge of the RFC?
2. How should the expect attribute deal with the new `force-warn` lint level?
---
This approach was inspired by a discussion with `@LeSeulArtichaut.`
RFC tracking issue: #54503
Mentoring/Implementation issue: #85549
[`LintLevelsBuilder`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/levels/struct.LintLevelsBuilder.html
[`LintLevelsMap`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/lint/struct.LintLevelMap.html
[`lint_levels()`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/context/struct.TyCtxt.html#method.lint_levels
[`rustc_errors::HandlerInner`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_errors/struct.HandlerInner.html
[`EarlyLintPass`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_lint/trait.EarlyLintPass.html
remove obligation dedup from `impl_or_trait_obligations`
Looking at the examples from #38528 they all seem to compile fine even without this and it seems like this might be unnecessary effort
Miri/CTFE: properly treat overflow in (signed) division/rem as UB
To my surprise, it looks like LLVM treats overflow of signed div/rem as UB. From what I can tell, MIR `Div`/`Rem` directly lowers to the corresponding LLVM operation, so to make that correct we also have to consider these overflows UB in the CTFE/Miri interpreter engine.
r? `@oli-obk`
There are three `Option` fields in `MatcherPos` that are only used in
tandem. This commit combines them, making the code slightly easier to
read. (It also makes clear that the `sep` field arguably should have
been `Option<Option<Token>>`!)
To avoid the strange style where comments force `else` onto its own
line.
The commit also removes several else-after-return constructs, which can
be hard to read.
Remove out-of-context line at end of E0284 message
Removed the last line of E0284 message because it was out of context (probably kept by accident when changing whole error message).
