x.py sets it unconditionally, so want it for plain "cargo build".
We need to load one of the panic runtimes that is in src (vs. pre-built in the
compiler's sysroot) to ensure that we don't load libpanic_unwind from the
sysroot. That would lead to a load of libcore, also from the sysroot, and create
lots of errors about duplicate lang items.
Going along with or_insert_with, or_insert_with_key provides the
Entry's key to the lambda, avoiding the need to either clone the
key or the need to reimplement this body of this method from
scratch each time.
This is useful when the initial value for a map entry is derived
from the key. For example, the introductory Rust book has an
example Cacher struct that takes an expensive-to-compute lambda and
then can, given an argument to the lambda, produce either the
cached result or execute the lambda.
add basic support of OsStrExt for HermitCore
- this patch increases the compatibility to other operating systems
- in principle `ffi.rs` is derived from `src/libstd/sys/unix/ext/ffi.rs`
Don't import integer and float modules, use assoc consts 2
Follow up to #70777. I missed quite a lot of places. Partially because I wanted to keep the size of the last PR down, and partially because my regexes were not good enough :)
r? @dtolnay
Small tweaks in ToOwned::clone_into
- `<[T]>::clone_into` is slightly more optimized.
- `CStr::clone_into` is new, letting it reuse its allocation.
- `OsStr::clone_into` now forwards to the underlying slice/`Vec`.
Remove marker comments in libstd/lib.rs macro imports
These comments were probably moved around when rustfmt was introduced. They don't correctly denote what they were intended for, so I propose we remove them instead. Thanks!
Simplify dtor registration for HermitCore by using a list of destructors
The implementation is similar to the macOS version and doesn't depend on additional OS support
Stop importing the float modules in documentation
Follow up to #69860. I realized I had not searched for and fixed this for the float values. So with this PR they also use the associated constants instead of the module level constants.
For the documentation where it also was using the `consts` submodule I opted to change it to import that directly. This becomes more in line with how other docs that use the `consts` submodule looks. And it also makes it so there are not two `f32` or `f64` things in the current namespace (both the module and the primitive type) and then hopefully confusing documentation readers less.
r? @dtolnay
Do not use "nil" to refer to `()`
"nil" is not used in the [book](https://doc.rust-lang.org/book) or in the [standard library](https://doc.rust-lang.org/std) anywhere else. Because "nil" is often used in programming languages to refer to "None" or "null" I think it could be a little confusing for newcomers to see this type referred to as "nil".
add basic IP support in HermitCore
- add initial version to support sockets
- use TcpStream as test case
- HermitCore uses smoltcp as IP stack for pure Rust applications
- further functionalities (e.g. UDP support) will be added step by step
- in principle, the current PR is a revision of #69404
Fix double-free and undefined behaviour in libstd::syn::unix::Thread::new
While working on concurrency support for Miri, I found that the `libstd::syn::unix::Thread::new` method has two potential problems: double-free and undefined behaviour.
**Double-free** could occur if the following events happened (credit for pointing this out goes to @RalfJung):
1. The call to `pthread_create` successfully launched a new thread that executed to completion and deallocated `p`.
2. The call to `pthread_attr_destroy` returned a non-zero value causing the `assert_eq!` to panic.
3. Since `mem::forget(p)` was not yet executed, the destructor of `p` would be executed and cause a double-free.
As far as I understand, this code also violates the stacked-borrows aliasing rules and thus would result in **undefined behaviour** if these rules were adopted. The problem is that the ownership of `p` is passed to the newly created thread before the call to `mem::forget`. Since the call to `mem::forget` is still a call, it counts as a use of `p` and triggers UB.
This pull request changes the code to use `mem::ManuallyDrop` instead of `mem::forget`. As a consequence, in case of a panic, `p` would be potentially leaked, which while undesirable is probably better than double-free or undefined behaviour.
Use associated numeric consts in documentation
Now when the associated constants on int/float types are stabilized and the recommended way of accessing said constants (#68952). We can start using it in this repository, and recommend it via documentation example code.
This PR is the reincarnation of #67913 minus the actual adding + stabilization of said constants. (EDIT: Now it's only changing the documentation. So users will see the new consts, but we don't yet update the internal code)
Because of how fast bit rot happens to PRs that touch this many files, it does not try to replace 100% of the old usage of the constants in the entire repo, but a good chunk of them.
Overhaul of the `AllocRef` trait to match allocator-wg's latest consens; Take 2
GitHub won't let me reopen#69889 so I make a new PR.
In addition to #69889 this fixes the unsoundness of `RawVec::into_box` when using allocators supporting overallocating. Also it uses `MemoryBlock` in `AllocRef` to unify `_in_place` methods by passing `&mut MemoryBlock`. Additionally, `RawVec` now checks for `size_of::<T>()` again and ignore every ZST. The internal capacity of `RawVec` isn't used by ZSTs anymore, as `into_box` now requires a length to be specified.
r? @Amanieu
fixesrust-lang/wg-allocators#38fixesrust-lang/wg-allocators#41fixesrust-lang/wg-allocators#44fixesrust-lang/wg-allocators#51
add `unused_braces` lint
Add the lint `unused_braces` which is warn by default.
`unused_parens` is also extended and now checks anon consts.
closes#68387
r? @varkor
