BTreeMap: address namespace conflicts
Fix an annoyance popping up whenever synchronizing the test cases with a version capable of miri-track-raw-pointers.
r? `@Mark-Simulacrum`
Stabilize refcell_take
Tracking Issue: #71395
``@KodrAus`` nominated this for FCP, so here's a PR!
I've never made a stabilization PR, so please mention if there's anything I can improve, thanks.
Stabilize alloc::Layout const functions
Stabilizes #67521. In particular the following stable methods are stabilized as `const fn`:
* `size`
* `align`
* `from_size_align`
Stabilizing `size` and `align` should not be controversial as they are simple (usize and NonZeroUsize) fields and I don't think there's any reason to make them not const compatible in the future. That being true, the other methods are trivially `const`. The only other issue being returning a `Result` from a `const fn` but this has been made more usable by recent stabilizations.
Split each iterator adapter and source into individual modules
This PR creates individual modules for each iterator adapter and iterator source.
This is done to enhance the readability of corresponding modules (`adapters/mod.rs` and `sources.rs`) which were hard to navigate and read because of lots of repeated lines (e.g.: `adapters/mod.rs` was 3k lines long). This is also in line with some adapters which already had their own modules (`Flatten`, `FlatMap`, `Chain`, `Zip`, `Fuse`).
This PR also makes `Take`s adapter fields private (I have no idea why they were `pub(super)` before).
r? ``@LukasKalbertodt``
Add f{32,64}::is_subnormal
The docs recommend that you use dedicated methods instead of calling `classify` directly, although there isn't actually a way of checking if a number is subnormal without calling classify. There are dedicated methods for all other forms, excluding `is_zero` (which is just `== 0.0` anyway).
Stabilize clamp
Tracking issue: https://github.com/rust-lang/rust/issues/44095
Clamp has been merged and unstable for about a year and a half now. How do we feel about stabilizing this?
More consistently use spaces after commas in lists in docs
This PR changes instances of lists that didn't use spaces after commas, like `vec![1,2,3]`, to `vec![1, 2, 3]` to be more consistent with idiomatic Rust style (the way these were looks strange to me, especially because there are often lists that *do* use spaces after the commas later in the same code block 😬).
I noticed one of these in an example in the stdlib docs and went looking for more, but as far as I can see, I'm only changing those spots in user-facing documentation or rustc output, and the changes make no semantic difference.
clarify rules for ZST Boxes
LLVM's rules around `getelementptr inbounds` with offset 0 are a bit annoying, and as a consequence we have no choice but say that a `Box<()>` pointing to previously allocated memory that has since been freed is UB. Clarify the docs to reflect this.
This is based on conversations on the LLVM mailing list.
* Here's my initial mail: https://lists.llvm.org/pipermail/llvm-dev/2019-February/130452.html
* The first email of the March part of that thread: https://lists.llvm.org/pipermail/llvm-dev/2019-March/130831.html
* First email of the April part: https://lists.llvm.org/pipermail/llvm-dev/2019-April/131693.html
The conclusion for me at least was that `getelementptr inbounds` with offset 0 is *not* the identity function, but can sometimes return `poison` even when the input is a regular pointer -- specifically, it returns `poison` when this pointer points into something that LLVM "knows has been deallocated", i.e., a former LLVM-managed allocation. It is however the identity function on pointers obtained by casting integers.
Note that there [are formal proposals](https://people.mpi-sws.org/~jung/twinsem/twinsem.pdf) for LLVM semantics where `getelementptr inbounds` with offset 0 isn't quite the identity function but never returns `poison` (it affects the provenance of the pointer but in a way that doesn't matter if this pointer is never used for memory accesses), and indeed this is likely necessary to consistently describe LLVM semantics. But with the informal LLVM LangRef that we have right now, and with LLVM devs insisting otherwise, it seems unwise to rely on this.
std: Update the bactrace crate submodule
This commit updates the `library/backtrace` submodule which primarily
pulls in support for split-debuginfo on macOS, avoiding the need for
`dsymutil` to get run to get line numbers and filenames in backtraces.
rustc_expand: Mark inner `#![test]` attributes as soft-unstable
Custom inner attributes are feature gated (https://github.com/rust-lang/rust/issues/54726) except for attributes having name `test` literally, which are not gated for historical reasons.
`#![test]` is an inner proc macro attribute, so it has all the issues described in https://github.com/rust-lang/rust/issues/54726 too.
This PR gates it with the `soft_unstable` lint.
This commit updates the `library/backtrace` submodule which primarily
pulls in support for split-debuginfo on macOS, avoiding the need for
`dsymutil` to get run to get line numbers and filenames in backtraces.
BTreeMap: replace Root with NodeRef<Owned, ...>
`NodeRef<marker::Owned, …>` already exists as a representation of root nodes, and it makes more sense to alias `Root` to that than to reuse the space-efficient `BoxedNode` that is oblivious to height, where height is required.
r? `@Mark-Simulacrum`
unix/weak: pass arguments to syscall at the given type
Given that we know the type the argument should have, it seems a bit strange not to use that information.
r? `@m-ou-se` `@cuviper`
Add lint for panic!("{}")
This adds a lint that warns about `panic!("{}")`.
`panic!(msg)` invocations with a single argument use their argument as panic payload literally, without using it as a format string. The same holds for `assert!(expr, msg)`.
This lints checks if `msg` is a string literal (after expansion), and warns in case it contained braces. It suggests to insert `"{}", ` to use the message literally, or to add arguments to use it as a format string.
![image](https://user-images.githubusercontent.com/783247/96643867-79eb1080-1328-11eb-8d4e-a5586837c70a.png)
This lint is also a good starting point for adding warnings about `panic!(not_a_string)` later, once [`panic_any()`](https://github.com/rust-lang/rust/pull/74622) becomes a stable alternative.
Rollup of 11 pull requests
Successful merges:
- #79119 (Clarify availability of atomic operations)
- #79123 (Add u128 and i128 integer tests)
- #79177 (Test drop order for (destructuring) assignments)
- #79181 (rustdoc: add [src] links to methods on a trait's page)
- #79183 (Make compiletest testing use the local sysroot)
- #79185 (expand/resolve: Pre-requisites to "Turn `#[derive]` into a regular macro attribute")
- #79193 (Revert #78969 "Normalize function type during validation")
- #79194 (Make as{_mut,}_slice on array::IntoIter public)
- #79204 (Add jyn514 email alias to mailmap)
- #79212 (Move `rustc_ty` -> `rustc_ty_utils`)
- #79217 (Add the "memcpy" doc alias to slice::copy_from_slice)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Make as{_mut,}_slice on array::IntoIter public
The functions are useful in cases where you want to move data out of the IntoIter in bulk, by transmute_copy'ing the slice and then forgetting the IntoIter.
In the compiler, this is useful for providing a sped up IntoIter implementation. One can alternatively provide a separate allocate_array function but one can avoid duplicating some logic by passing everything through the generic iterator using interface.
As per suggestion in https://github.com/rust-lang/rust/pull/78569/files#r526506964
Clarify availability of atomic operations
This was noticed while we were updating the embedded rust book: https://github.com/rust-embedded/book/pull/273/files
These targets do natively have atomic load/stores, but do not support CAS operations.
libary: Forward compiler-builtins "asm" and "mangled-names" feature
In principle this is a followup of rust-lang/rust#78472. In the previous PR was the support of the test crate missing.
Now users will be able to do:
```
cargo build -Zbuild-std=core -Zbuild-std-features=compiler-builtins-asm
```
and correctly get the assembly implemenations for `memcpy` and friends.
Remove semicolon from internal `err` macro
This macro is used in expression position (a match arm), and only
compiles because of #33953
Regardless of what happens with that issue, this makes the
usage of the macro less confusing at the call site.
This macro is used in expression position (a match arm), and only
compiles because of #33953
Regardless of what happens with that issue, this makes the
usage of the macro less confusing at the call site.