Count char width at most once in `Formatter::pad`
When both width and precision flags are specified, then `Formatter::pad` counts the character width twice. Instead, record the character width when truncating it to the precision, so it does not need to be recomputed. Simplify control flow so the cases are more clear.
Related:
- 6c9e708f4b (`fmt::Formatter::pad`: don't call chars().count() more than one time, 2021-09-01): Reduce counting chars from thrice to twice in worst case
- ede39aeb33 (feat: reinterpret `precision` field for strings, 2016-06-29): Change meaning of precision for strings
- b820748ff5 (Implement formatting arguments for strings and integers, 2013-08-10): Implement `Formatter::pad`
dec2flt: Clean up float parsing modules
This is the first portion of my work adding support for parsing and printing `f16`. Changes in `float.rs` replace the magic constants with expressions and add some use of generics to better support the new float types. Everything else is related to documentation or naming; there are no functional changes in this PR.
This can be reviewed by commit.
Update `compiler-builtins` to 0.1.149
Includes a change to make a subset of math symbols available on all platforms [1], and disables `f16` on aarch64 without neon [2].
[1]: https://github.com/rust-lang/compiler-builtins/pull/763
[2]: https://github.com/rust-lang/compiler-builtins/pull/775
try-job: aarch64-gnu
try-job: aarch64-gnu-debug
try-job: armhf-gnu
try-job: dist-various-1
try-job: dist-various-2
try-job: dist-aarch64-linux
try-job: dist-arm-linux
try-job: dist-armv7-linux
try-job: dist-x86_64-linux
try-job: test-various
Rollup of 12 pull requests
Successful merges:
- #135767 (Future incompatibility warning `unsupported_fn_ptr_calling_conventions`: Also warn in dependencies)
- #137852 (Remove layouting dead code for non-array SIMD types.)
- #137863 (Fix pretty printing of unsafe binders)
- #137882 (do not build additional stage on compiler paths)
- #137894 (Revert "store ScalarPair via memset when one side is undef and the other side can be memset")
- #137902 (Make `ast::TokenKind` more like `lexer::TokenKind`)
- #137921 (Subtree update of `rust-analyzer`)
- #137922 (A few cleanups after the removal of `cfg(not(parallel))`)
- #137939 (fix order on shl impl)
- #137946 (Fix docker run-local docs)
- #137955 (Always allow rustdoc-json tests to contain long lines)
- #137958 (triagebot.toml: Don't label `test/rustdoc-json` as A-rustdoc-search)
r? `@ghost`
`@rustbot` modify labels: rollup
Disable `f16` on Aarch64 without `neon`
LLVM has crashes at some `half` operations when built with assertions enabled if fp-armv8 is not available [1]. Things seem to usually work, but we are reaching LLVM undefined behavior so this needs to be disabled.
[1]: https://github.com/llvm/llvm-project/issues/129394
More precisely document `Global::deallocate()`'s safety.
There is a subtlety which "other conditions must be upheld by the caller" does not capture: `GlobalAlloc`/`alloc::dealloc()` require that the provided layout will be *equal*, not just that it "fits", the layout used to allocate. This is always true here due to how `allocate()`, `grow()`, and `shrink()` are implemented (they never return a larger allocation than requested), but that is a non-local property of the implementation, so it should be documented explicitly.
r? libs
`@rustbot` label A-allocators
Minor internal comments fix for `BufRead::read_line`
Just a little fix that came up while I was reading through this source code, and had to search for a few minutes to find out what was actually *meant* here.
A lot of the magic constants can be turned into expressions. This
reduces some code duplication.
Additionally, add traits to make these operations fully generic. This
will make it easier to support `f16` and `f128`.
The previous commit renamed `Decimal` to `DecimalSeq`. Now, rename the
type that represents a decimal floating point number to be `Decimal`.
Additionally, add some tests for internal behavior.
This module currently contains two decimal types, `Decimal` and
`Number`. These names don't provide a whole lot of insight into what
exactly they are, and `Number` is actually the one that is more like an
expected `Decimal` type.
In accordance with this, rename the existing `Decimal` to `DecimalSeq`.
This highlights that it contains a sequence of decimal digits, rather
than representing a base-10 floating point (decimal) number.
Additionally, add some tests to validate internal behavior.
LLVM has crashes at some `half` operations when built with assertions
enabled if fp-armv8 is not available [1]. Things seem to usually work,
but we are reaching LLVM undefined behavior so this needs to be
disabled.
[1]: https://github.com/llvm/llvm-project/issues/129394
Fix inaccurate `std::intrinsics::simd` documentation
This addresses two issues:
- the docs on comparison operators (`simd_gt` etc.) said they only work for floating-point vectors, but they work for integer vectors too.
- the docs on various functions that use a mask did not document that the mask must be a signed integer vector. Unsigned integer vectors would cause invalid behavior when the mask vector is widened (unsigned integers would use zero extension, producing incorrect results).
r? ``@workingjubilee``
Use correct error message casing for `io::const_error`s
Error messages are supposed to start with lowercase letters, but a lot of `io::const_error` messages did not. This fixes them to start with a lowercase letter.
I did consider adding a const check for this to the macro, but some of them start with proper nouns that make sense to uppercase them.
See https://doc.rust-lang.org/1.85.0/std/error/trait.Error.html
Error messages are supposed to start with lowercase letters, but a lot
of `io::const_error` messages did not. This fixes them to start with a
lowercase letter.
I did consider adding a const check for this to the macro, but some of
them start with proper nouns that make sense to uppercase them.
See https://doc.rust-lang.org/1.85.0/std/error/trait.Error.html
Fix Windows `Command` search path bug
Currently `Command::new` on Windows works differently depending on whether any environment variable is set. For example,
```rust
// Searches for "myapp" in the application and system paths first (aka Windows native behaviour).
Command::new("myapp").spawn();
// Search for "myapp" in `PATH` first
Command::new("myapp").env("a", "b").spawn();
```
This is a bug because the search path should only change if `PATH` is changed for the child (i.e. `.env("PATH", "...")`).
This was discussed in a libs-api meeting where the exact semantics of `Command::new` was not decided but there seemed to be broad agreement that this particular thing is just a bug that can be fixed.
r? libs-api
import `simd_` intrinsics
In most cases, we can import the simd intrinsics rather than redeclare them. Apparently, most of these tests were written before `std::intrinsics::simd` existed.
There are a couple of exceptions where we can't yet import:
- the intrinsics are not declared as `const fn` in the standard library, causing issues in the `const-eval` tests
- the `simd_shuffle_generic` function is not exposed from `std::intrinsics`
- the `simd_fpow` and `simd_fpowi` functions are not exposed from `std::intrinsics` (removed in https://github.com/rust-lang/rust/pull/137595)
- some tests use `no_core`, and therefore cannot use `std::intrinsics`
r? ```@RalfJung```
cc ```@workingjubilee``` do you have context on why some intrinsics are not exposed?
Update some comparison codegen tests now that they pass in LLVM20
Fixes#106107
Needed one tweak to the default `PartialOrd::le` to get the test to pass. Everything but the derived 2-field `le` test passes even without the change to the defaults in the trait.
When both width and precision flags are specified, then the character
width is counted twice. Instead, record the character width when
truncating it to the precision, so it does not need to be recomputed.
Simplify control flow so the cases are more clear.
Return unexpected termination error instead of panicing in `Thread::join`
There is a time window during which the OS can terminate a thread before stdlib can retreive its `Packet`. Currently the `Thread::join` panics with no message in such an event, which makes debugging difficult; fixes#124466.
Add UTF-8 validation fast paths in `Wtf8Buf`
This adds two more fast paths for UTF-8 validation in `Wtf8Buf`, making use of the `is_known_utf8` flag added in https://github.com/rust-lang/rust/pull/96869 (Optimize `Wtf8Buf::into_string` for the case where it contains UTF-8).
r? `@ChrisDenton`
