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.
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.
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```````````````````````````
First, this reverts the `CFLAGS`/`CXXFLAGS` of #93918. Those flags are
already read by `cc` and populated into `Build` earlier on in the
process. We shouldn't be overriding that based on `CFLAGS`, since `cc`
also respects overrides like `CFLAGS_{TARGET}` and `HOST_CFLAGS`, which
we want to take into account.
Second, this adds the same capability to specify target-specific
versions of `LDFLAGS` as we have through `cc` for the `C*` flags:
https://github.com/alexcrichton/cc-rs#external-configuration-via-environment-variables
Note that this also necessitated an update to compiletest to treat
CXXFLAGS separately from CFLAGS.
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's still open discussion if this lint is ready to be enabled by
default. We want to give us more time to figure this out and prevent
this lint from getting to stable as an enabled-by-default lint.
The ability to interoperate with C code via FFI is not limited to crates
using std; this allows using these types without std.
The existing types in `std::os::raw` become type aliases for the ones in
`core::ffi`. This uses type aliases rather than re-exports, to allow the
std types to remain stable while the core types are unstable.
This also moves the currently unstable `NonZero_` variants and
`c_size_t`/`c_ssize_t`/`c_ptrdiff_t` types to `core::ffi`, while leaving
them unstable.
chalk: Fix wrong debrujin index in opaque type handling.
A folder in opaque type lowering was substituting all opaque type references with a variable with debrujin index 0 ignoring how many binders deep we are.
This caused an ICE with `Not enough bound vars: ^0 not found in []` ([full logs](https://gist.github.com/Dirbaio/2b9374ff4fce37afb9d665dc9f0000df)) with the following code.
```rust
fn main() -> () {}
async fn foo(x: u32) -> u32 {
x
}
```
With the fix, it no longer ICEs. It still doesn't typecheck due to generator issues. I've added a "known-bug" test so that at least it doesn't regress back to ICEing.
r? ``@jackh726``
rustc_errors: let `DiagnosticBuilder::emit` return a "guarantee of emission".
That is, `DiagnosticBuilder` is now generic over the return type of `.emit()`, so we'll now have:
* `DiagnosticBuilder<ErrorReported>` for error (incl. fatal/bug) diagnostics
* can only be created via a `const L: Level`-generic constructor, that limits allowed variants via a `where` clause, so not even `rustc_errors` can accidentally bypass this limitation
* asserts `diagnostic.is_error()` on emission, just in case the construction restriction was bypassed (e.g. by replacing the whole `Diagnostic` inside `DiagnosticBuilder`)
* `.emit()` returns `ErrorReported`, as a "proof" token that `.emit()` was called
(though note that this isn't a real guarantee until after completing the work on
#69426)
* `DiagnosticBuilder<()>` for everything else (warnings, notes, etc.)
* can also be obtained from other `DiagnosticBuilder`s by calling `.forget_guarantee()`
This PR is a companion to other ongoing work, namely:
* #69426
and it's ongoing implementation:
#93222
the API changes in this PR are needed to get statically-checked "only errors produce `ErrorReported` from `.emit()`", but doesn't itself provide any really strong guarantees without those other `ErrorReported` changes
* #93244
would make the choices of API changes (esp. naming) in this PR fit better overall
In order to be able to let `.emit()` return anything trustable, several changes had to be made:
* `Diagnostic`'s `level` field is now private to `rustc_errors`, to disallow arbitrary "downgrade"s from "some kind of error" to "warning" (or anything else that doesn't cause compilation to fail)
* it's still possible to replace the whole `Diagnostic` inside the `DiagnosticBuilder`, sadly, that's harder to fix, but it's unlikely enough that we can paper over it with asserts on `.emit()`
* `.cancel()` now consumes `DiagnosticBuilder`, preventing `.emit()` calls on a cancelled diagnostic
* it's also now done internally, through `DiagnosticBuilder`-private state, instead of having a `Level::Cancelled` variant that can be read (or worse, written) by the user
* this removes a hazard of calling `.cancel()` on an error then continuing to attach details to it, and even expect to be able to `.emit()` it
* warnings were switched to *only* `can_emit_warnings` on emission (instead of pre-cancelling early)
* `struct_dummy` was removed (as it relied on a pre-`Cancelled` `Diagnostic`)
* since `.emit()` doesn't consume the `DiagnosticBuilder` <sub>(I tried and gave up, it's much more work than this PR)</sub>,
we have to make `.emit()` idempotent wrt the guarantees it returns
* thankfully, `err.emit(); err.emit();` can return `ErrorReported` both times, as the second `.emit()` call has no side-effects *only* because the first one did do the appropriate emission
* `&mut Diagnostic` is now used in a lot of function signatures, which used to take `&mut DiagnosticBuilder` (in the interest of not having to make those functions generic)
* the APIs were already mostly identical, allowing for low-effort porting to this new setup
* only some of the suggestion methods needed some rework, to have the extra `DiagnosticBuilder` functionality on the `Diagnostic` methods themselves (that change is also present in #93259)
* `.emit()`/`.cancel()` aren't available, but IMO calling them from an "error decorator/annotator" function isn't a good practice, and can lead to strange behavior (from the caller's perspective)
* `.downgrade_to_delayed_bug()` was added, letting you convert any `.is_error()` diagnostic into a `delay_span_bug` one (which works because in both cases the guarantees available are the same)
This PR should ideally be reviewed commit-by-commit, since there is a lot of fallout in each.
r? `@estebank` cc `@Manishearth` `@nikomatsakis` `@mark-i-m`
As an example:
#[test]
#[ignore = "not yet implemented"]
fn test_ignored() {
...
}
Will now render as:
running 2 tests
test tests::test_ignored ... ignored, not yet implemented
test result: ok. 1 passed; 0 failed; 1 ignored; 0 measured; 0 filtered out; finished in 0.00s
better ObligationCause for normalization errors in `can_type_implement_copy`
Some logic is needed so we can point to the field when given totally nonsense types like `struct Foo(<u32 as Iterator>::Item);`
Fixes#93687
tidy: fire less "ignoring file length unneccessarily" warnings
This avoids a situation where a file is at the border of the limit,
and alternates between hitting the limit and not hitting it, causing
a back and forth of addition of the ignore-tidy-linelength directive.
As an example, consider the ignore-tidy-filelength of compiler/rustc_typeck/src/collect.rs.
It was added in 2ca4964db5, removed in
37354ebc97 (a revert of the earlier commit), added again in 448d07683a,
removed in 3171bd5bf5, added in 438826fd1a,
and removed in bb0a2f985c.
To avoid this back and forth, we exempt files from the unneccessary
ignoring warning that have length of at least 70% of the limit.
This avoids a situation where a file is at the border of the limit,
and alternates between hitting the limit and not hitting it, causing
a back and forth of addition of the ignore-tidy-linelength directive.
As an example, consider the ignore-tidy-filelength of compiler/rustc_typeck/src/collect.rs.
It was added in 2ca4964db5, removed in
37354ebc97, added again in 448d07683a,
removed in 3171bd5bf5, added in 438826fd1a,
and #94142 is going to remove it again.
To avoid this back and forth, we exempt files from the unneccessary
ignoring warning that have length of at least 70% of the limit.
Add the `known-bug` test directive, use it, and do some cleanup
cc rust-lang/compiler-team#476
Now tests can be annotated with `known-bug`, which should indicate that the test *should* pass (or at least that the current output is a bug). Adding it relaxes the requirement to add error annotations to the test (though it is still allowed). In the future, this could be extended with further relaxations - with the goal to make adding these tests need minimal effort.
I've used this attribute for the GAT tests added in #93757.
Finally, I've also cleaned up `header.rs` in compiletest a bit, by extracting out a bit of common logic. I've also split out some of the directives into their own consts. This removes a lot of very similar functions from `Config` and makes `TestProps::load_from` read nicer.
I've split these into separate commits, so I in theory could split these into separate PRs if they're controversial, but I think they're pretty straightforward.
r? ``@Mark-Simulacrum``
Add MemTagSanitizer Support
Add support for the LLVM [MemTagSanitizer](https://llvm.org/docs/MemTagSanitizer.html).
On hardware which supports it (see caveats below), the MemTagSanitizer can catch bugs similar to AddressSanitizer and HardwareAddressSanitizer, but with lower overhead.
On a tag mismatch, a SIGSEGV is signaled with code SEGV_MTESERR / SEGV_MTEAERR.
# Usage
`-Zsanitizer=memtag -C target-feature="+mte"`
# Comments/Caveats
* MemTagSanitizer is only supported on AArch64 targets with hardware support
* Requires `-C target-feature="+mte"`
* LLVM MemTagSanitizer currently only performs stack tagging.
# TODO
* Tests
* Example
