Commit Graph

160836 Commits

Author SHA1 Message Date
Matthias Krüger
d49c692eeb
Rollup merge of #91587 - nrc:dispatchfromdyn-docs, r=yaahc
core::ops::unsize: improve docs for DispatchFromDyn

Docs-only PR, improves documentation for DispatchFromDyn.
2022-01-04 21:23:05 +01:00
bors
7d6f948173 Auto merge of #92556 - matthiaskrgr:rollup-s9vopuj, r=matthiaskrgr
Rollup of 7 pull requests

Successful merges:

 - #91754 (Modifications to `std::io::Stdin` on Windows so that there is no longer a 4-byte buffer minimum in read().)
 - #91884 (Constify `Box<T, A>` methods)
 - #92107 (Actually set IMAGE_SCN_LNK_REMOVE for .rmeta)
 - #92456 (Make the documentation of builtin macro attributes accessible)
 - #92507 (Suggest single quotes when char expected, str provided)
 - #92525 (intra-doc: Make `Receiver::into_iter` into a clickable link)
 - #92532 (revert #92254 "Bump gsgdt to 0.1.3")

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-01-04 19:56:13 +00:00
Augie Fackler
2803fbc447 RustWrapper: adapt to new AttributeMask API
Upstream LLVM change 9290ccc3c1a1 migrated attribute removal to use
AttributeMask instead of AttrBuilder, so we need to follow suit here.
2022-01-04 13:50:02 -05:00
Jakub Beránek
65a3279f4a
Do not hash zero bytes of i64 and u32 in Sip128 hasher 2022-01-04 19:12:10 +01:00
Jakub Beránek
e266cb90de Do not use deprecated -Zsymbol-mangling-version in bootstrap 2022-01-04 12:06:46 -05:00
Matthias Krüger
76c02711a5
Rollup merge of #92532 - krasimirgg:gsgdt-down, r=Mark-Simulacrum
revert #92254 "Bump gsgdt to 0.1.3"

This reverts https://github.com/rust-lang/rust/pull/92254 since gsgdt 0.1.3 was yanked: https://github.com/rust-lang/rust/pull/92254#issuecomment-1004269481
2022-01-04 16:34:20 +01:00
Matthias Krüger
b2d6ff4b6e
Rollup merge of #92525 - zohnannor:patch-1, r=camelid
intra-doc: Make `Receiver::into_iter` into a clickable link

The documentation on `std::sync::mpsc::Iter` and `std::sync::mpsc::TryIter` provides links to the corresponding `Receiver` methods, unlike `std::sync::mpsc::IntoIter` does.

This was left out in c59b188aae
Related to #29377
2022-01-04 16:34:19 +01:00
Matthias Krüger
25fcc0ef8c
Rollup merge of #92507 - chordtoll:suggest-single-quotes, r=petrochenkov
Suggest single quotes when char expected, str provided

If a type mismatch occurs where a char is expected and a string literal is provided, suggest changing the double quotes to single quotes.

We already provide this suggestion in the other direction ( ' -> " ).

Especially useful for new rust devs used to a language in which single/double quotes are interchangeable.

Fixes #92479.
2022-01-04 16:34:17 +01:00
Matthias Krüger
4e4e1ec931
Rollup merge of #92456 - danielhenrymantilla:patch-1, r=petrochenkov
Make the documentation of builtin macro attributes accessible

`use ::std::prelude::v1::derive;` compiles on stable, so, AFAIK, there is no reason to have it be `#[doc(hidden)]`.

  - What it currently looks like for things such as `#[test]`, `#[derive]`, `#[global_allocator]`: https://doc.rust-lang.org/1.57.0/core/prelude/v1/index.html#:~:text=Experimental-,pub,-use%20crate%3A%3Amacros%3A%3Abuiltin%3A%3Aglobal_allocator

    <img width="767" alt="Screen Shot 2021-12-31 at 17 49 46" src="https://user-images.githubusercontent.com/9920355/147832999-cbd747a6-4607-4df6-8e57-c1675dcbc1c3.png">

    and in `::std` they're just straight `hidden`.

    <img width="452" alt="Screen Shot 2021-12-31 at 17 53 18" src="https://user-images.githubusercontent.com/9920355/147833105-c5ff8cd1-9e4d-4d2b-9621-b36aa3cfcb28.png">

  - Here is how it looks like with this PR (assuming the `Rustc{De,En}codable` ones are not reverted):

    <img width="778" alt="Screen Shot 2021-12-31 at 17 50 55" src="https://user-images.githubusercontent.com/9920355/147833034-84286342-dbf7-4e6e-9062-f39cd6c286a4.png">

    <img width="291" alt="Screen Shot 2021-12-31 at 17 52 54" src="https://user-images.githubusercontent.com/9920355/147833109-c92ed55c-51c6-40a2-9205-f834d1e349c0.png">

 Since this involves doc people to chime in, and since `jyn` is on vacation, I'll cc `@GuillaumeGomez` and tag the `rustdoc` team as well
2022-01-04 16:34:16 +01:00
Matthias Krüger
855f6300fb
Rollup merge of #92107 - nikic:rmeta-lnk-remove, r=nagisa
Actually set IMAGE_SCN_LNK_REMOVE for .rmeta

The code intended to set the IMAGE_SCN_LNK_REMOVE flag for the
.rmeta section, however the value of this flag was set to zero.
Instead use the actual value provided by the object crate.

This dates back to the original introduction of this code in
PR #84449, so we were never setting this flag. As I'm not on
Windows, I'm not sure whether that means we were embedding .rmeta
into executables, or whether the section ended up getting stripped
for some other reason.
2022-01-04 16:34:15 +01:00
Matthias Krüger
c7125ba0fa
Rollup merge of #91884 - woppopo:const_box, r=oli-obk
Constify `Box<T, A>` methods

Tracking issue: none yet

Most of the methods bounded on `~const`. `intrinsics::const_eval_select` is used for handling an allocation error.

<details><summary>Constified API</summary>

```rust
impl<T, A: Allocator> Box<T, A> {
    pub const fn new_in(x: T, alloc: A) -> Self
    where
        A: ~const Allocator + ~const Drop;
    pub const fn try_new_in(x: T, alloc: A) -> Result<Self, AllocError>
    where
        T: ~const Drop,
        A: ~const Allocator + ~const Drop;
    pub const fn new_uninit_in(alloc: A) -> Box<mem::MaybeUninit<T>, A>
    where
        A: ~const Allocator + ~const Drop;
    pub const fn try_new_uninit_in(alloc: A) -> Result<Box<mem::MaybeUninit<T>, A>, AllocError>
    where
        A: ~const Allocator + ~const Drop;
    pub const fn new_zeroed_in(alloc: A) -> Box<mem::MaybeUninit<T>, A>
    where
        A: ~const Allocator + ~const Drop;
    pub const fn try_new_zeroed_in(alloc: A) -> Result<Box<mem::MaybeUninit<T>, A>, AllocError>
    where
        A: ~const Allocator + ~const Drop;
    pub const fn pin_in(x: T, alloc: A) -> Pin<Self>
    where
        A: 'static,
        A: 'static + ~const Allocator + ~const Drop,
    pub const fn into_boxed_slice(boxed: Self) -> Box<[T], A>;
    pub const fn into_inner(boxed: Self) -> T
    where
        Self: ~const Drop,
}

impl<T, A: Allocator> Box<MaybeUninit<T>, A> {
    pub const unsafe fn assume_init(self) -> Box<T, A>;
    pub const fn write(mut boxed: Self, value: T) -> Box<T, A>;
    pub const unsafe fn from_raw_in(raw: *mut T, alloc: A) -> Self;
    pub const fn into_raw_with_allocator(b: Self) -> (*mut T, A);
    pub const fn into_unique(b: Self) -> (Unique<T>, A);
    pub const fn allocator(b: &Self) -> &A;
    pub const fn leak<'a>(b: Self) -> &'a mut T
    where
        A: 'a;
    pub const fn into_pin(boxed: Self) -> Pin<Self>
    where
        A: 'static;
}

unsafe impl<#[may_dangle] T: ?Sized, A: Allocator> const Drop for Box<T, A>;
impl<T: ?Sized, A: Allocator> const From<Box<T, A>> for Pin<Box<T, A>>
where
    A: 'static;
impl<T: ?Sized, A: Allocator> const Deref for Box<T, A>;
impl<T: ?Sized, A: Allocator> const DerefMut for Box<T, A>;
impl<T: ?Sized, A: Allocator> const Unpin for Box<T, A> where A: 'static;
```

</details>

<details><summary>Example</summary>

```rust
pub struct ConstAllocator;

unsafe impl const Allocator for ConstAllocator {
    fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
        unsafe {
            let ptr = core::intrinsics::const_allocate(layout.size(), layout.align());
            Ok(NonNull::new_unchecked(ptr as *mut [u8; 0] as *mut [u8]))
        }
    }

    unsafe fn deallocate(&self, _ptr: NonNull<u8>, _layout: Layout) {
        /* do nothing */
    }

    fn allocate_zeroed(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
        self.allocate(layout)
    }

    unsafe fn grow(
        &self,
        _ptr: NonNull<u8>,
        _old_layout: Layout,
        _new_layout: Layout,
    ) -> Result<NonNull<[u8]>, AllocError> {
        unimplemented!()
    }

    unsafe fn grow_zeroed(
        &self,
        _ptr: NonNull<u8>,
        _old_layout: Layout,
        _new_layout: Layout,
    ) -> Result<NonNull<[u8]>, AllocError> {
        unimplemented!()
    }

    unsafe fn shrink(
        &self,
        _ptr: NonNull<u8>,
        _old_layout: Layout,
        _new_layout: Layout,
    ) -> Result<NonNull<[u8]>, AllocError> {
        unimplemented!()
    }

    fn by_ref(&self) -> &Self
    where
        Self: Sized,
    {
        self
    }
}

#[test]
fn const_box() {
    const VALUE: u32 = {
        let mut boxed = Box::new_in(1u32, ConstAllocator);
        assert!(*boxed == 1);

        *boxed = 42;
        assert!(*boxed == 42);

        *boxed
    };

    assert!(VALUE == 42);
}
```

</details>
2022-01-04 16:34:14 +01:00
Matthias Krüger
50a66b75dc
Rollup merge of #91754 - Patrick-Poitras:rm-4byte-minimum-stdio-windows, r=Mark-Simulacrum
Modifications to `std::io::Stdin` on Windows so that there is no longer a 4-byte buffer minimum in read().

This is an attempted fix of issue #91722, where a too-small buffer was passed to the read function of stdio on Windows. This caused an error to be returned when `read_to_end` or `read_to_string` were called. Both delegate to `std::io::default_read_to_end`, which creates a buffer that is of length >0, and forwards it to `std::io::Stdin::read()`. The latter method returns an error if the length of the buffer is less than 4, as there might not be enough space to allocate a UTF-16 character. This creates a problem when the buffer length is in `0 < N < 4`, causing the bug.

The current modification creates an internal buffer, much like the one used for the write functions

I'd also like to acknowledge the help of ``@agausmann`` and ``@hkratz`` in detecting and isolating the bug, and for suggestions that made the fix possible.

Couple disclaimers:

- Firstly, I didn't know where to put code to replicate the bug found in the issue. It would probably be wise to add that case to the testing suite, but I'm afraid that I don't know _where_ that test should be added.
- Secondly, the code is fairly fundamental to IO operations, so my fears are that this may cause some undesired side effects ~or performance loss in benchmarks.~ The testing suite runs on my computer, and it does fix the issue noted in #91722.
- Thirdly, I left the "surrogate" field in the Stdin struct, but from a cursory glance, it seems to be serving the same purpose for other functions. Perhaps merging the two would be appropriate.

Finally, this is my first pull request to the rust language, and as such some things may be weird/unidiomatic/plain out bad. If there are any obvious improvements I could do to the code, or any other suggestions, I would appreciate them.

Edit: Closes #91722
2022-01-04 16:34:14 +01:00
Ralf Jung
d60018b44b rename StackPopClean::None to Root 2022-01-04 11:13:08 +01:00
David Tolnay
ffbeebbf7a
Make rustc_log doc test runnable 2022-01-03 22:31:56 -08:00
chordtoll
3087c4dfb7
Suggest changing quotes when str/char type mismatch 2022-01-03 22:08:08 -08:00
ksqsf
1c547f422a Stabilize result_cloned and result_copied 2022-01-04 13:23:32 +08:00
David Tolnay
dd5ee326bc
Justify why rustc_log exists 2022-01-03 20:25:23 -08:00
Eric Huss
ec10c4f7f2 Update books 2022-01-03 19:45:10 -08:00
David Tolnay
6152d15e7c
Extract init_env_logger to crate 2022-01-03 16:45:21 -08:00
bors
2b681ac06b Auto merge of #92259 - Aaron1011:normal-mod-hashing, r=michaelwoerister
Remove special-cased stable hashing for HIR module

All other 'containers' (e.g. `impl` blocks) hashed their contents
in the normal, order-dependent way. However, `Mod` was hashing
its contents in a (sort-of) order-independent way. However, the
exact order is exposed to consumers through `Mod.item_ids`,
and through query results like `hir_module_items`. Therefore,
stable hashing needs to take the order of items into account,
to avoid fingerprint ICEs.

Unforuntately, I was unable to directly build a reproducer
for the ICE, due to the behavior of `Fingerprint::combine_commutative`.
This operation swaps the upper and lower `u64` when constructing the
result, which makes the function non-associative. Since we start
the hashing of module items by combining `Fingerprint::ZERO` with
the first item, it's difficult to actually build an example where
changing the order of module items leaves the final hash unchanged.

However, this appears to have been hit in practice in #92218
While we're not able to reproduce it, the fact that proc-macros
are involved (which can give an entire module the same span, preventing
any span-related invalidations) makes me confident that the root
cause of that issue is our method of hashing module items.

This PR removes all of the special handling for `Mod`, instead deriving
a `HashStable` implementation. This makes `Mod` consistent with other
'contains' like `Impl`, which hash their contents through the typical
derive of `HashStable`.
2022-01-04 00:25:23 +00:00
Nicholas Nethercote
2e74ca18e4 Tweak the usage messages for x.py build and x.py check.
They're a bit out of date, and overly complicated.
2022-01-04 09:24:10 +11:00
Nicholas Nethercote
10e3d92306 Label more build steps.
Currently the output of a command like `./x.py build --stage 0 library/std` is this:
```
Updating only changed submodules
Submodules updated in 0.02 seconds
extracting [...]
   Compiling [...]
    Finished dev [unoptimized] target(s) in 17.53s
Building stage0 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
   Compling [...]
    Finished release [optimized + debuginfo] target(s) in 21.99s
Copying stage0 std from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Build completed successfully in 0:00:51
```
I find the part before the "Building stage0 std artifacts" a bit confusing.

After this commit, it looks like this:
```
Updating only changed submodules
  Submodules updated in 0.02 seconds
extracting [...]
Building rustbuild
   Compiling [...]
    Finished dev [unoptimized] target(s) in 17.53s
Building stage0 std artifacts (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu)
   Compling [...]
    Finished release [optimized + debuginfo] target(s) in 21.99s
Copying stage0 std from stage0 (x86_64-unknown-linux-gnu -> x86_64-unknown-linux-gnu / x86_64-unknown-linux-gnu)
Build completed successfully in 0:00:51
```
The "Building rustbuild" label makes it clear what the first cargo build
invocation is for. The indentation of the "Submodules updated" line
indicates it is a sub-step of a parent task.
2022-01-04 09:24:10 +11:00
Aaron Hill
467b72607d
Hash Ident spans in all HIR structures
This PR removes all of the `#[stable_hasher(project(name))]`
attributes used in HIR structs. While these attributes are not known
to be causing any issues in practice, we need to hash these in
order for the incremental system to work correctly -
a query could be otherwise be incorrectly marked green
when a change occures in one of the `Span`s that it uses.
2022-01-03 15:52:38 -05:00
bors
399ba6bb37 Auto merge of #92314 - Kobzol:encoding-u16-leb128, r=michaelwoerister
Do not use LEB128 for encoding u16 and i16

An experiment to try out the suggestion from https://github.com/rust-lang/rust/issues/68779.

Closes: https://github.com/rust-lang/rust/issues/68779
2022-01-03 20:30:23 +00:00
Daniel Henry-Mantilla
f20ccc0748 Make the documentation of builtin macro attributes accessible
- Do not `#[doc(hidden)]` the `#[derive]` macro attribute

  - Add a link to the reference section to `derive`'s inherent docs

  - Do the same for `#[test]` and `#[global_allocator]`

  - Fix `GlobalAlloc` link (why is it on `core` and not `alloc`?)

  - Try `no_inline`-ing the `std` reexports from `core`

  - Revert "Try `no_inline`-ing the `std` reexports from `core`"

  - Address PR review

  - Also document the unstable macros
2022-01-03 20:43:16 +01:00
Krasimir Georgiev
a9698e22ec revert #92254 "Bump gsgdt to 0.1.3"
gsgdt 0.1.3 was yanked:
https://github.com/rust-lang/rust/pull/92254#issuecomment-1004269481
2022-01-03 20:25:46 +01:00
David Tolnay
7dec41a236
Move contains method of Option and Result lower in docs 2022-01-03 10:46:15 -08:00
zohnannor
ca3f9048a1
Make Receiver::into_iter into a clickable link
The documentation on `std::sync::mpsc::Iter` and `std::sync::mpsc::TryIter` provides links to the corresponding `Receiver` methods, unlike `std::sync::mpsc::IntoIter` does.

This was left out in c59b188aae
Related to #29377
2022-01-03 20:17:57 +03:00
woppopo
51e4291f2b Fix a compile error when no_global_oom_handling 2022-01-04 01:37:53 +09:00
woppopo
c9d2d3cc66 Add tracking issues (const_box, const_alloc_error) 2022-01-04 00:35:53 +09:00
bors
ddabe0775c Auto merge of #92518 - matthiaskrgr:rollup-fl8z4e7, r=matthiaskrgr
Rollup of 6 pull requests

Successful merges:

 - #90102 (Remove `NullOp::Box`)
 - #92011 (Use field span in `rustc_macros` when emitting decode call)
 - #92402 (Suggest while let x = y when encountering while x = y)
 - #92409 (Couple of libtest cleanups)
 - #92418 (Fix spacing in pretty printed PatKind::Struct with no fields)
 - #92444 (Consolidate Result's and Option's methods into fewer impl blocks)

Failed merges:

 - #92483 (Stabilize `result_cloned` and `result_copied`)

r? `@ghost`
`@rustbot` modify labels: rollup
2022-01-03 14:30:36 +00:00
Matthias Krüger
13e284033e
Rollup merge of #92444 - dtolnay:coremethods, r=joshtriplett
Consolidate Result's and Option's methods into fewer impl blocks

`Result`'s and `Option`'s methods have historically been separated up into `impl` blocks based on their trait bounds, with the bounds specified on type parameters of the impl block. I find this unhelpful because closely related methods, like `unwrap_or` and `unwrap_or_default`, end up disproportionately far apart in source code and rustdocs:

<pre>
impl&lt;T&gt; Option&lt;T&gt; {
    pub fn unwrap_or(self, default: T) -&gt; T {
        ...
    }

    <img alt="one eternity later" src="https://user-images.githubusercontent.com/1940490/147780325-ad4e01a4-c971-436e-bdf4-e755f2d35f15.jpg" width="750">
}

impl&lt;T: Default&gt; Option&lt;T&gt; {
    pub fn unwrap_or_default(self) -&gt; T {
        ...
    }
}
</pre>

I'd prefer for method to be in as few impl blocks as possible, with the most logical grouping within each impl block. Any bounds needed can be written as `where` clauses on the method instead:

```rust
impl<T> Option<T> {
    pub fn unwrap_or(self, default: T) -> T {
        ...
    }

    pub fn unwrap_or_default(self) -> T
    where
        T: Default,
    {
        ...
    }
}
```

*Warning: the end-to-end diff of this PR is computed confusingly by git / rendered confusingly by GitHub; it's practically impossible to review that way. I've broken the PR into commits that move small groups of methods for which git behaves better &mdash; these each should be easily individually reviewable.*
2022-01-03 14:44:21 +01:00
Matthias Krüger
df921190f3
Rollup merge of #92418 - dtolnay:emptystructpat, r=michaelwoerister
Fix spacing in pretty printed PatKind::Struct with no fields

Follow-up to #92238 fixing one of the FIXMEs.

```rust
macro_rules! repro {
    ($pat:pat) => {
        stringify!($pat)
    };
}

fn main() {
    println!("{}", repro!(Struct {}));
}
```

Before:&ensp;<code>Struct&nbsp;{&nbsp;&nbsp;}</code>
After:&ensp;<code>Struct&nbsp;{}</code>
2022-01-03 14:44:20 +01:00
Matthias Krüger
92f28bda38
Rollup merge of #92409 - bjorn3:libtest_cleanups, r=m-ou-se
Couple of libtest cleanups

Remove the unnecessary `TDynBenchFn` trait and remove a couple of unused attributes and feature gates.
2022-01-03 14:44:19 +01:00
Matthias Krüger
0335b7bca9
Rollup merge of #92402 - pr2502:while-let-typo, r=oli-obk
Suggest while let x = y when encountering while x = y

Extends #75931 to also detect where the `let` might be missing from `while let` expressions.
2022-01-03 14:44:18 +01:00
Matthias Krüger
fd09f342f3
Rollup merge of #92011 - Aaron1011:decode-span, r=michaelwoerister
Use field span in `rustc_macros` when emitting decode call

This will cause backtraces to point to the location of
the field in the struct/enum, rather than the derive macro.

This makes it clear which field was being decoded when the
backtrace was captured (which is especially useful if
there are multiple fields with the same type).
2022-01-03 14:44:16 +01:00
Matthias Krüger
57a4f4a634
Rollup merge of #90102 - nbdd0121:box3, r=jonas-schievink
Remove `NullOp::Box`

Follow up of #89030 and MCP rust-lang/compiler-team#460.

~1 month later nothing seems to be broken, apart from a small regression that #89332 (1aac85bb716c09304b313d69d30d74fe7e8e1a8e) shows could be regained by remvoing the diverging path, so it shall be safe to continue and remove `NullOp::Box` completely.

r? `@jonas-schievink`
`@rustbot` label T-compiler
2022-01-03 14:44:15 +01:00
Chris Denton
4145877731
Explicitly pass PATH to the Windows exe resolver 2022-01-03 12:55:42 +00:00
bors
b5efe5727f Auto merge of #92179 - Aaron1011:incr-loaded-from-disk, r=michaelwoerister
Add `#[rustc_clean(loaded_from_disk)]` to assert loading of query result

Currently, you can use `#[rustc_clean]` to assert to that a particular
query (technically, a `DepNode`) is green or red. However, a green
`DepNode` does not mean that the query result was actually deserialized
from disk - we might have never re-run a query that needed the result.

Some incremental tests are written as regression tests for ICEs that
occured during query result decoding. Using
`#[rustc_clean(loaded_from_disk="typeck")]`, you can now assert
that the result of a particular query (e.g. `typeck`) was actually
loaded from disk, in addition to being green.
2022-01-03 11:20:08 +00:00
lcnr
a02bf76c96 review 2022-01-03 11:59:01 +01:00
Krasimir Georgiev
4ce56b414d RustWrapper: adapt for an LLVM API change
No functional changes intended.

The LLVM commit
ec501f15a8
removed the signed version of `createExpression`. This adapts the Rust
LLVM wrappers accordingly.
2022-01-03 11:25:33 +01:00
bors
d367c349ef Auto merge of #92080 - Aaron1011:pattern-ice, r=cjgillot
Move `PatKind::Lit` checking from ast_validation to ast lowering

Fixes #92074

This allows us to insert an `ExprKind::Err` when an invalid expression
is used in a literal pattern, preventing later stages of compilation
from seeing an unexpected literal pattern.
2022-01-03 06:59:52 +00:00
bors
b5da80871d Auto merge of #92395 - Kobzol:rustdoc-bindings-thin-vec, r=camelid
Rustdoc: use ThinVec for GenericArgs bindings

The bindings are almost always empty. This reduces the size of `PathSegment` and `GenericArgs` by about one fourth.
2022-01-03 03:49:01 +00:00
Jacob Hoffman-Andrews
cc18120425 Set font size proportional to user's font size
According to MDN
(https://developer.mozilla.org/en-US/docs/Web/CSS/font-size),

> To maximize accessibility, it is generally best to use values that
> are relative to the user's default font size.

> Defining font sizes in px is not accessible, because the user cannot
> change the font size in some browsers.

Note that changing font size (in browser or OS settings) is distinct
from the zoom functionality triggered with Ctrl/Cmd-+. Zoom
functionality increases the size of everything on the page, effectively
applying a multiplier to all pixel sizes. Font size changes apply to
just text.

For relative font sizes, we could use `em`, as we do in several places
already. However that has a problem of "compounding" (see MDN article
for details). The compounding problem is nicely solved by `rem`, which
make font sizes relative to the root element, not the parent element.

Since we were using a hodge-podge of pixel sizes, em, rem, and
percentage sizes before, this change switching everything to rem, while
keeping the same size relative to our old default of 16px.

16px is still the default on most browsers, for users that haven't set a
larger or smaller font size.
2022-01-02 11:23:26 -05:00
bors
8f3238f898 Auto merge of #90128 - joshtriplett:stabilize-symbol-mangling-version, r=wesleywiser
Stabilize -Z symbol-mangling-version=v0 as -C symbol-mangling-version=v0

This allows selecting `v0` symbol-mangling without an unstable option. Selecting `legacy` still requires -Z unstable-options.

This does not change the default symbol-mangling-version. See https://github.com/rust-lang/rust/pull/89917 for a pull request changing the default. Rationale, from #89917:

Rust's current mangling scheme depends on compiler internals; loses information about generic parameters (and other things) which makes for a worse experience when using external tools that need to interact with Rust symbol names; is inconsistent; and can contain . characters which aren't universally supported. Therefore, Rust has defined its own symbol mangling scheme which is defined in terms of the Rust language, not the compiler implementation; encodes information about generic parameters in a reversible way; has a consistent definition; and generates symbols that only use the characters A-Z, a-z, 0-9, and _.

Support for the new Rust symbol mangling scheme has been added to upstream tools that will need to interact with Rust symbols (e.g. debuggers).

This pull request allows enabling the new v0 symbol-mangling-version.

See #89917 for references to the implementation of v0, and for references to the tool changes to decode Rust symbols.
2022-01-02 15:49:23 +00:00
bors
03360be6b7 Auto merge of #92066 - Smittyvb:concat_bytes-repeat, r=nagisa
Support [x; n] expressions in concat_bytes!

Currently trying to use `concat_bytes!` with a repeating array value like `[42; 5]` results in an error:
```
error: expected a byte literal
 --> src/main.rs:3:27
  |
3 |     let x = concat_bytes!([3; 4]);
  |                           ^^^^^^
  |
  = note: only byte literals (like `b"foo"`, `b's'`, and `[3, 4, 5]`) can be passed to `concat_bytes!()`
```

This makes it so repeating array syntax can be used the same way normal arrays can be. The RFC doesn't explicitly mention repeat expressions, but it seems reasonable to allow them as well, since normal arrays are allowed.

It is possible to make the compiler get stuck compiling forever with `concat_bytes!([3; 999999999])`, but I don't think that's much of an issue since you can do that already with `const X: [u8; 999999999] = [3; 999999999];`.

Contributes to #87555.
2022-01-02 12:38:41 +00:00
bors
82418f93ac Auto merge of #91961 - kornelski:track_split_caller, r=joshtriplett
Track caller of slice split and swap

Improves error location for `slice.split_at*()` and `slice.swap()`.

These are generic inline functions, so the `#[track_caller]` on them is free — only changes a value of an argument already passed to panicking code.
2022-01-02 09:35:24 +00:00
bors
f7934f693b Auto merge of #92034 - petrochenkov:nolinknores, r=joshtriplett
Remove effect of `#[no_link]` attribute on name resolution

Previously it hid all non-macro names from other crates.
This has no relation to linking and can change name resolution behavior in some cases (e.g. glob conflicts), in addition to just producing the "unresolved name" errors.

I can kind of understand the possible reasoning behind the current behavior - if you can use names from a `no_link` crates then you can use, for example, functions too, but whether it will actually work or produce link-time errors will depend on random factors like inliner behavior.
(^^^ This is not the actual reason why the current behavior exist, I've looked through git history and it's mostly accidental.)

I think this risk is ok for such an obscure attribute, and we don't need to specifically prevent use of non-macro items from such crates.
(I'm not actually sure why would anyone use `#[no_link]` on a crate, even if it's macro only, if you aware of any use cases, please share. IIRC, at some point it was used for crates implementing custom derives - the now removed legacy ones, not the current proc macros.)

Extracted from https://github.com/rust-lang/rust/pull/91795.
2022-01-02 06:28:34 +00:00
bors
7b13c628a2 Auto merge of #92482 - matthiaskrgr:rollup-uso1zi0, r=matthiaskrgr
Rollup of 7 pull requests

Successful merges:

 - #84083 (Clarify the guarantees that ThreadId does and doesn't make.)
 - #91593 (Remove unnecessary bounds for some Hash{Map,Set} methods)
 - #92297 (Reduce compile time of rustbuild)
 - #92332 (Add test for where clause order)
 - #92438 (Enforce formatting for rustc_codegen_cranelift)
 - #92463 (Remove pronunciation guide from Vec<T>)
 - #92468 (Emit an error for `--cfg=)`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-01-02 00:20:04 +00:00
Josh Triplett
ff94b3b12b Update references to -Z symbol-mangling-version to use -C
Replace `-Z symbol-mangling-version=v0` with `-C symbol-mangling-version=v0`.

Replace `-Z symbol-mangling-version=legacy` with
`-Z unstable-options -C symbol-mangling-version=legacy`.
2022-01-01 15:53:11 -08:00