override `VecDeque::try_rfold`, also update iterator
This keeps the slice based iteration and updates the iterator state after each slice. It also uses a loop to reduce the amount of code.
This uses unsafe code, so some thorough review would be appreciated. Cc @RalfJung
This keeps the slice based iteration and updates the iterator
state after each slice. It also uses a loop to reduce the amount
of code.
This uses unsafe code, so some thorough review would be
appreciated.
libcore, liballoc: disable tests in Miri
I am going to run the libcore and liballoc unit test suites in Miri. Not all tests pass. This PR disables a whole bunch of tests when running in Miri, to get us to a baseline from which I can investigate failures.
Cc @SimonSapin @alexcrichton
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.
Short-circuit Rc/Arc equality checking on equal pointers where T: Eq
based on #42965
Is the use of the private trait ok this way? Is there anything else needed for this to get pulled?
Test capacity of ZST vector
Initially, #50233 accidentally changed the capacity of empty ZST. This was pointed out during code review. This commit adds a test to prevent capacity of ZST vectors from accidentally changing to prevent that from happening again.
* Update bootstrap compiler
* Update version to 1.33.0
* Remove some `#[cfg(stage0)]` annotations
Actually updating the version number is blocked on updating Cargo
Ever since we added a Cargo-based build system for the compiler the
standard library has always been a little special, it's never been able
to depend on crates.io crates for runtime dependencies. This has been a
result of various limitations, namely that Cargo doesn't understand that
crates from crates.io depend on libcore, so Cargo tries to build crates
before libcore is finished.
I had an idea this afternoon, however, which lifts the strategy
from #52919 to directly depend on crates.io crates from the standard
library. After all is said and done this removes a whopping three
submodules that we need to manage!
The basic idea here is that for any crate `std` depends on it adds an
*optional* dependency on an empty crate on crates.io, in this case named
`rustc-std-workspace-core`. This crate is overridden via `[patch]` in
this repository to point to a local crate we write, and *that* has a
`path` dependency on libcore.
Note that all `no_std` crates also depend on `compiler_builtins`, but if
we're not using submodules we can publish `compiler_builtins` to
crates.io and all crates can depend on it anyway! The basic strategy
then looks like:
* The standard library (or some transitive dep) decides to depend on a
crate `foo`.
* The standard library adds
```toml
[dependencies]
foo = { version = "0.1", features = ['rustc-dep-of-std'] }
```
* The crate `foo` has an optional dependency on `rustc-std-workspace-core`
* The crate `foo` has an optional dependency on `compiler_builtins`
* The crate `foo` has a feature `rustc-dep-of-std` which activates these
crates and any other necessary infrastructure in the crate.
A sample commit for `dlmalloc` [turns out to be quite simple][commit].
After that all `no_std` crates should largely build "as is" and still be
publishable on crates.io! Notably they should be able to continue to use
stable Rust if necessary, since the `rename-dependency` feature of Cargo
is soon stabilizing.
As a proof of concept, this commit removes the `dlmalloc`,
`libcompiler_builtins`, and `libc` submodules from this repository. Long
thorns in our side these are now gone for good and we can directly
depend on crates.io! It's hoped that in the long term we can bring in
other crates as necessary, but for now this is largely intended to
simply make it easier to manage these crates and remove submodules.
This should be a transparent non-breaking change for all users, but one
possible stickler is that this almost for sure breaks out-of-tree
`std`-building tools like `xargo` and `cargo-xbuild`. I think it should
be relatively easy to get them working, however, as all that's needed is
an entry in the `[patch]` section used to build the standard library.
Hopefully we can work with these tools to solve this problem!
[commit]: 28ee12db81
Initially, #50233 accidentally changed the capacity of empty ZST. This
was pointed out during code review. This commit adds a test to prevent
capacity of ZST vectors from accidentally changing to prevent that
from happening again.
This commit deletes the `alloc_system` crate from the standard
distribution. This unstable crate is no longer needed in the modern
stable global allocator world, but rather its functionality is folded
directly into the standard library. The standard library was already the
only stable location to access this crate, and as a result this should
not affect any stable code.
This commit removes all jemalloc related submodules, configuration, etc,
from the bootstrap, from the standard library, and from the compiler.
This will be followed up with a change to use jemalloc specifically as
part of rustc on blessed platforms.
Non-naive implementation of `VecDeque.append`
Replaces the old, simple implementation with a more manual (and **unsafe** 😱) one. I've added 1 more test and verified that it covers all 6 code paths in the function.
This new implementation was about 60% faster than the old naive one when I tried benchmarking it.
