Adding unwinding support for x86_64_fortanix_unknown_sgx target.
Unwinding support is provided by our port of LLVM's libunwind which is available from https://github.com/fortanix/libunwind/tree/release_50.
libunwind requires support for rwlock and printing to stderr, which is only provided by `std` for this target. This poses two problems: 1) how to expose the `std` functionality to C and 2) dependency inversion.
### Exposing `std`
For exposing the functionality we chose to expose the following symbols:
* __rust_rwlock_rdlock
* __rust_rwlock_wrlock
* __rust_rwlock_unlock
* __rust_print_err
* __rust_abort
Also, the following are needed from `alloc`:
* __rust_alloc
* __rust_dealloc
#### Rust RWLock in C
In `libunwind`, RWLock is initialized as a templated static variable:
```c
pthread_rwlock_t DwarfFDECache<A>::_lock = PTHREAD_RWLOCK_INITIALIZER;
```
I don't know of a good way to use the Rust sys::rwlock::RWLock type and initializer there. We could have a static global variable in Rust, but that doesn't work with the templating. The variable needs to be initialized statically, since this target doesn't support the .init section. Currently, I just used a byte array and standard C array initialization. The mapping between this C type and the Rust type needs to be manually maintained. There is a compile-time check and a unit test to make sure the Rust versions of these C definitions match the actual Rust type. If any reviewer knows of a better solution, please do tell.
### Dependency inversion issue
`std` depends on `panic_unwind` which depends on `libunwind`, and `libunwind` depends on `std`. This is not normally supported by Rust's linking system. Therefore we use raw C exports from `std` *and* `libunwind.a` is linked last in the target `post_link_objects` instead of being built as part of the Rust `libunwind`. Currently, all C exports are defined in `src/libstd/sys/sgx/rwlock.rs` to overcome LTO issues. Only the `__rust_rwlock_*` definitions *need* to live there for privacy reasons. Once again, if any reviewer knows of a better solution, please do tell.
r? @alexcrichton
make basic CTFE tracing available on release builds
Debugging things going wrong in miri is currently pretty much impossible with a nightly Rust.
r? @oli-obk
Mem uninit doc ptr drop
Extend the mem::uninitialized documentation to account for partially initialized arrays and how to correctly handle these. These are used in some datastructures (trees for example) or in FFI.
r? @Manishearth
deny intra-doc link resolution failures in libstd
Fixes#56693.
Until we land a fix for the underlying issue (#56922), we can at least fix the failures in libstd so they don't propagate to downstream crates.
rename div_euc -> div_euclid, and mod_euc -> rem_euclid
logic is written up in #49048
Also, update the documentation slightly.
cc @alexcrichton @clarcharr @varkor
Add --progress to git submodule commands in x.py
This is a relatively new flag, but it means that git will indicate the progress of the update as it would with regular clones. This is especially helpful as some of the submodules are really big and it's difficult to tell if it's hanging or still updating.
Ignore ui/target-feature-gate on sparc, sparc64, powerpc, powerpc64 and powerpc64le
The test ui/target-feature-gate is not applicable on sparc, sparc64, powerpc, powerpc64 and powerpc64le and consequently fails there. So just ignore it on these targets.
static eval: Do not ICE on layout size overflow
Layout size overflow and typeck eval errors are reported. Trigger a bug
only when the eval error is strictly labeled as TooGeneric.
Fixes: #56762
Add DoubleEndedIterator::nth_back
As suggested by #54054. This doesn't fix that issue, as this doesn't add enough implementations to optimise that specific use case, but it adds the method and a few (relatively) trivial overrides to work as an initial implementation.
It's probably going to be a lot of work adding `nth_back` implementations everywhere, and I don't have the time to include it all in this commit. But, it's a start. :)
Use compiletest timestamp to check if the tests should be rerun.
An attempt to fix #56280 by checking if timestamps of compile test files are older than the timestamp of the stamp file.
?r nagisa
This commit modifies the wording of the warning for
backwards-incompatible changes in migrate mode. The warning messages are
changed to be lowercase and not include line-breaks in order to be
consistent with other compiler diagnostics.
Short-circuit DefIdForest::intersection()
If the forest is already empty, there is no point in intersecting further.
Also handle the first element separately, so we don't compute an unnecessary intersection between the full forest and the first element, which is always equal to the first element.
This is the second try at fixing #57028, as the previous attempt only recovered part of the regression. I checked locally that this drops time spent in ty::inhabitedness for syn-check a lot, though not to zero.
r? @varkor
If the forest is already empty, there is no point in intersecting
further.
Also handle the first element separately, so we don't compute an
unnecessary intersection between the full forest and the first
element, which is always equal to the first element.
stop treating trait objects from #[fundamental] traits as fundamental
This is a [breaking-change] to code that exploits this functionality (which should be limited to code using `#![feature(fundamental)]`.
Fixes#56503.
r? @nikomatsakis
Add unstable VecDeque::rotate_{left|right}
Like the ones on slices, but more efficient because vecdeque is a circular buffer.
Issue that proposed this: https://github.com/rust-lang/rust/issues/56686
~~💣 Please someone look very carefully at the `unsafe` in this! The `wrap_copy` seems to be exactly what this method needs, and the `len` passed to it is never more than half the length of the deque, but I haven't managed to prove to myself that it's correct 💣~~ I think I proved that this code meets the requirement of the unsafe code it's calling; please double-check, of course.
Remove pin::Unpin reexport and add Unpin to the prelude.
Change Pin associated functions to methods.
Rename get_mut_unchecked_ to get_unchecked_mut
Remove impl Unpin for Pin
Mark Pin repr(transparent)
Stabilize `Rc`, `Arc` and `Pin` as method receivers
Replaces #55880
Closes #55786
r? @nikomatsakis
cc @withoutboats @cramertj
This lets you write methods using `self: Rc<Self>`, `self: Arc<Self>`, `self: Pin<&mut Self>`, `self: Pin<Box<Self>`, and other combinations involving `Pin` and another stdlib receiver type, without needing the `arbitrary_self_types`. Other user-created receiver types can be used, but they still require the feature flag to use.
This is implemented by introducing a new trait, `Receiver`, which the method receiver's type must implement if the `arbitrary_self_types` feature is not enabled. To keep composed receiver types such as `&Arc<Self>` unstable, the receiver type is also required to implement `Deref<Target=Self>` when the feature flag is not enabled.
This lets you use `self: Rc<Self>` and `self: Arc<Self>` in stable Rust, which was not allowed previously. It was agreed that they would be stabilized in #55786. `self: Pin<&Self>` and other pinned receiver types do not require the `arbitrary_self_types` feature, but they cannot be used on stable because `Pin` still requires the `pin` feature.
Remove "visited" set from inhabitedness checking (fix perf regression)
Now that references are no longer recursively checked, this should no longer be necessary, and it's a major performance bottleneck.
This should fix#57028.
r? @varkor
On musl targets assume certain symbols exist (like pipe2 and accept4).
This fixes#56675.
I don't know if this is the best solution, or if I should also add some tests so I'm waiting for some feedback.
Thanks!
When the feature has been added back (#55148) the feature gate has not
been adjusted accordingly. We have it enabled for 1.32.0, currently in
Beta, so adjust it.
Refs: #44431.
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Instead disable creation of assumptions during inlining using an
LLVM opt flag.
The -Z arg-align-attributes option which previously controlled this
behavior is removed.
