Generalize `get_nullable_type` to allow types where null is all-ones.
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
Emit `unused_attributes` if a level attr only has a reason
Fixes a comment from `compiler/rustc_lint/src/levels.rs`. Lint level attributes that only contain a reason will also trigger the `unused_attribute` lint. The lint now also checks for the `expect` lint level.
That's it, have a great rest of the day for everyone reasoning this 🙃
cc: #55112
This makes the order of the output always consistent:
1. Place of the `match` missing arms
2. The `enum` definition span
3. The structured suggestion to add a fallthrough arm
Add link to closed PR for future optimizers of ChunkedBitSet relations
While optimizing these operations proved unfruitful w.r.t. improving compiler performance right now, faster versions might be needed at a later time. This PR adds a link in the FIXME to save any future optimizers some time, as requested by `@nnethercote` in https://github.com/rust-lang/rust/pull/94625.
r? `@nnethercote`
Rollup of 4 pull requests
Successful merges:
- #93350 (libunwind: readd link attrs to _Unwind_Backtrace)
- #93827 (Stabilize const_fn_fn_ptr_basics, const_fn_trait_bound, and const_impl_trait)
- #94696 (Remove whitespaces and use CSS to align line numbers to the right instead)
- #94700 (rustdoc: Update minifier version)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Clarify `Layout` interning.
`Layout` is another type that is sometimes interned, sometimes not, and
we always use references to refer to it so we can't take any advantage
of the uniqueness properties for hashing or equality checks.
This commit renames `Layout` as `LayoutS`, and then introduces a new
`Layout` that is a newtype around an `Interned<LayoutS>`. It also
interns more layouts than before. Previously layouts within layouts
(via the `variants` field) were never interned, but now they are. Hence
the lifetime on the new `Layout` type.
Unlike other interned types, these ones are in `rustc_target` instead of
`rustc_middle`. This reflects the existing structure of the code, which
does layout-specific stuff in `rustc_target` while `TyAndLayout` is
generic over the `Ty`, allowing the type-specific stuff to occur in
`rustc_middle`.
The commit also adds a `HashStable` impl for `Interned`, which was
needed. It hashes the contents, unlike the `Hash` impl which hashes the
pointer.
r? `@fee1-dead`
interpret: move saturating_add/sub into (pub) helper method
I plan to use them for `simd_saturating_add/sub`.
The first commit just moves code, the 2nd simplifies it a bit with some helper methods that did not exist yet when the code was originally written.
Remove ordering traits from `rustc_span::hygiene::LocalExpnId`
Part of work on #90317.
Also adds a negative impl block as a form of documentation and a roadblock to regression.
CTFE engine: expose misc_cast to Miri
We need that to implement `simd_cast`/`simd_as` in Miri.
While at it, also change other code outside `cast.rs` to use `misc_cast` instead of lower-level methods.
r? `@oli-obk`
Check extra function arg exprs even if the fn is not C-variadic
We should still call check_expr on the args that exceed the formal input ty count, so that we have expr types to emit during writeback.
Not sure where this regressed, but it wasn't due to the same root cause as #94334 I think. I thought this might've regressed in #92360, but I think that is in stable, ad the test I provided (which minimizes #94599) passes on stable in playground. Maybe it regressed in #93118.
Anywho, fixes#94599.
`Layout` is another type that is sometimes interned, sometimes not, and
we always use references to refer to it so we can't take any advantage
of the uniqueness properties for hashing or equality checks.
This commit renames `Layout` as `LayoutS`, and then introduces a new
`Layout` that is a newtype around an `Interned<LayoutS>`. It also
interns more layouts than before. Previously layouts within layouts
(via the `variants` field) were never interned, but now they are. Hence
the lifetime on the new `Layout` type.
Unlike other interned types, these ones are in `rustc_target` instead of
`rustc_middle`. This reflects the existing structure of the code, which
does layout-specific stuff in `rustc_target` while `TyAndLayout` is
generic over the `Ty`, allowing the type-specific stuff to occur in
`rustc_middle`.
The commit also adds a `HashStable` impl for `Interned`, which was
needed. It hashes the contents, unlike the `Hash` impl which hashes the
pointer.
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
This keeps `reason` around for the time being. This is necessary to
avoid breakage during the bootstrap process. This change, as a whole,
brings `#[rustc_deprecated]` more in line with `#[deprecated]`.
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```````````````
