Rollup of 8 pull requests
Successful merges:
- #107245 (Implement unsizing in the new trait solver)
- #107445 (Remove `GenFuture` from core)
- #107473 (Update books)
- #107476 (rustdoc: remove unnecessary wrapper `div.item-decl` from HTML)
- #107477 (Migrate last part of CSS themes to CSS variables)
- #107479 (Use `ObligationCtxt::new_in_snapshot` in `satisfied_from_param_env`)
- #107482 (rustdoc: remove meta keywords from HTML)
- #107494 (fix link in std::path::Path::display())
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Use `ObligationCtxt::new_in_snapshot` in `satisfied_from_param_env`
We can evaluate nested `ConstEvaluatable` obligations in an evaluation probe, which will ICE if we use `ObligationCtxt::new`.
Fixes#107474Fixes#106666
r? `@BoxyUwU` but feel free to reassign
cc `@JulianKnodt` who i think added this assertion code
Not sure if the rustdoc test is needed, but can't hurt. They're the same root cause, though.
Migrate last part of CSS themes to CSS variables
No changes in the output. This is already tested in `tests/rustdoc-gui/search-tab.goml` so no need to add a GUI test.
r? `@notriddle`
Update books
## rust-lang/book
2 commits in 2cd1b5593d26dc6a03c20f8619187ad4b2485552..f2a78f64b668f63f581203c6bac509903f7c00ee
2023-01-23 18:19:32 UTC to 2023-01-23 15:15:22 UTC
- Change CamelCase to UpperCamelCase
- Fix broken link to the No Starch Press version (rust-lang/book#3513)
## rust-embedded/book
3 commits in 19f798d448835a4888e3b3eae7fe69f1d61d8681..f1a4614aa41cc544b91b79760a709e113f3451d7
2023-01-26 15:21:58 UTC to 2023-01-18 07:51:06 UTC
- Fix typo in the registers.md (rust-embedded/book#343)
- Macports install instructions (rust-embedded/book#342)
- remove extern crate statements (rust-embedded/book#340)
## rust-lang/nomicon
2 commits in 960d610e7f33889a2577f5f17c26f0d5c82b30df..bd1829d235296952bf72ca55635e360584b8805e
2023-01-18 03:14:58 UTC to 2023-01-17 20:05:07 UTC
- Copyedits to FFI and unwinding section (rust-lang/nomicon#396)
- Fix typo in dropck documentation (rust-lang/nomicon#397)
## rust-lang/reference
2 commits in 2cb0ed9ba56360949f492f9866afe8c293f9f9da..22882fb3f7b4d69fdc0d1731e8b9cfcb6910537d
2023-01-23 13:21:28 UTC to 2023-01-20 18:38:44 UTC
- Fix typo “assigment” (…and more) (rust-lang/reference#1322)
- Syntax correction for trait-bounds.md (rust-lang/reference#1319)
## rust-lang/rust-by-example
1 commits in a9fb7d13eadfcc5f457962731f105b97f9a7474a..134376872e8c387ef369507e0ee9b5a0e3272718
2023-01-25 11:56:37 UTC to 2023-01-25 11:56:37 UTC
- update std_misc/file/create.md: fixed grammar (rust-lang/rust-by-example#1668)
## rust-lang/rustc-dev-guide
12 commits in 7352353ae91c48b136d2ca7d03822e1448165e1e..e359ee27fc3da3356d71a732128c0a1abe02e53a
2023-01-30 15:08:16 UTC to 2023-01-17 12:44:19 UTC
- New infcx usage (rust-lang/rustc-dev-guide#1571)
- Create a chapter for AST validation (rust-lang/rustc-dev-guide#1524)
- Use ephemeral PAT for linkcheck (rust-lang/rustc-dev-guide#1569)
- add section for the new trait solver (rust-lang/rustc-dev-guide#1551)
- version 5 is now not supported (rust-lang/rustc-dev-guide#1568)
- there are still no locale bundles (rust-lang/rustc-dev-guide#1567)
- bumpt date-check examples to current month (rust-lang/rustc-dev-guide#1566)
- Update hir.md (rust-lang/rustc-dev-guide#1565)
- rustc_typeck exists no more (rust-lang/rustc-dev-guide#1559)
- Correct tests misplacement (rust-lang/rustc-dev-guide#1564)
- Update resolution.md (rust-lang/rustc-dev-guide#1561)
- Update asm.md (rust-lang/rustc-dev-guide#1560)
Remove `GenFuture` from core
The handling of async constructs in the compiler does not rely on `GenFuture` anymore since `1.67`, so this code can now be removed from `core`.
Implement unsizing in the new trait solver
This makes hello world compile! Ignore the first commit, that's just #107146 which is waiting on merge.
I'll leave some comments inline about design choices that might be debatable.
r? `@lcnr` (until we have a new trait solver reviewer group...)
Fix invalid float literal suggestions when recovering an integer
Only suggest adding a zero to integers with a preceding dot when the change will result in a valid floating point literal.
For example, `.0x0` should not be turned into `0.0x0`.
r? nnethercote
Only suggest adding a zero to integers with a preceding dot when the change will
result in a valid floating point literal.
For example, `.0x0` should not be turned into `0.0x0`.
assume MIR types are fully normalized in ascribe_user_type
This FIXME was introduced in c6a17bf8bc but it should've been restricted to `ascribe_user_type_skip_wf`.
Rollup of 7 pull requests
Successful merges:
- #107125 (Add and use expect methods to hir.)
- #107172 (Reimplement NormalizeArrayLen based on SsaLocals)
- #107177 (Keep all theme-updating logic together)
- #107424 (Make Vec::clone_from and slice::clone_into share the same code)
- #107455 (use a more descriptive name)
- #107465 (`has_allow_dead_code_or_lang_attr` micro refactor)
- #107469 (Change turbofish context link to an archive link)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Change turbofish context link to an archive link
The original tweet in the chain linked to (via quote tweet), and thus the through line of links back to Anna's tweet where she named the turbofish (https://web.archive.org/web/20210911061514/https://twitter.com/whoisaldeka/status/914914008225816576) are lost as the user whoisaldeka has deleted their twitter account.
Switching to an archive link preserves this through line, allowing someone to browse back to see the point at which Anna created the turbofish, as was the original intent of including this context.
I was sharing this test with some friends as I often do, and noticed the changes (I had only seen the version from before her death previously). Looking for context myself, I realized the deleted twitter account was breaking an important link in the chain for the context of who Anna was to begin with, and the exact moment the turbofish was so named.
As an alternative to using an archive, we could link to both the tweet where Anna names the turbofish, and the tweet where she refers to herself as its guardian, as two separate links - not requiring the quote tweet to connect them.
Make Vec::clone_from and slice::clone_into share the same code
In the past, `Vec::clone_from` was implemented using `slice::clone_into`. The code from `clone_into` was later duplicated into `clone_from` in 8725e4c337, which is the commit that adds custom allocator support to Vec. Presumably this was done because the `slice::clone_into` method only works for vecs with the default allocator so it would have the wrong type to clone into `Vec<T, A>`.
Later on in 361398009b the code for the two methods diverged because the `Vec::clone_from` version gained a specialization to optimize the case when T is Copy. In order to reduce code duplication and make them both be able to take advantage of this specialization, this PR moves the specialization into the slice module and makes vec use it again.
Keep all theme-updating logic together
Prior to this PR, if the page is restored from the browser bfcache¹, we call `switchToSavedTheme`. But `switchToSavedTheme` never looks at the `use-system-theme` preference. Further, if it can't find a saved theme, it will fall back to the default of "light".
For a user with cookies disabled² whose preferred color scheme is dark, this means the theme will wobble back and forth between dark and light. The sequence that occurs is,
1. The page is loaded. During a page load, we consult `use-system-theme`: as cookies are disabled, this preference is unset. The default is true.
Because the default is true, we look at the preferred color scheme: for our example user, that's "dark". **The page theme is set to dark.** We'll attempt to store these preferences in localStorage, but fail due to cookies being disabled.
2. The user navigates through the docs. Subsequent page loads happen, and the same process in step 1 recurs. Previous pages are (potentially) put into the bfcache.
3. The user navigates backwards/forwards, causing a page in bfcache to be pulled out of cache. The `pageShow` event handler is triggered. However, this calls `switchToSavedTheme`: this doesn't consider the system theme, as noted above. Instead, it only looks for a saved theme. However, with cookies disabled, there is none. It defaults to light. **The page theme is set to light!** The user wonders why the dark theme is lost.
There are effectively two functions trying to determine and apply the correct theme: `updateSystemTheme` and `switchToSavedTheme`. Thus, we merge them into just one: `updateTheme`. This function contains all the logic for determining the correct theme, and is called in all circumstances where we need to set the theme:
* The initial page load
* If the browser preferred color scheme (i.e., light/dark mode) is changed
* If the page is restored from bfcache
* If the user updates the theme preferences (i.e., in `settings.js`)
Fixes https://github.com/rust-lang/rust/issues/94250.
¹bfcache: https://web.dev/bfcache/ The bfcache is used to sleep a page, if the user navigates away from it, and to restore it from cache if the user returns to it.
²Note that the browser preference that enables/disables cookies really controls many forms of storage. The same preference thus also affects localStorage. (This is so a normal browser user doesn't need to understand the distinction between "cookies" and "localStorage".)
The original tweet in the chain linked to, and thus the through line of links back to Anna's tweet where she named the turbofish (https://web.archive.org/web/20210911061514/https://twitter.com/whoisaldeka/status/914914008225816576) are lost as the user whoisaldeka has deleted their twitter account.
Switching to an archive link preserves this through line, allowing someone to browse back to see the point at which Anna created the turbofish, as was the original intent of including this context.
bootstrap: cleanup the list of extra check cfgs
This PR performs some cleanups on the `EXTRA_CHECK_CFGS` list in bootstrap.
- `target_os=watchos`: no longer relevant because there are now proper targets `*-apple-watchos`
- `target_arch=nvptx64`: target `nvptx64-nvidia-cuda` makes it useless
- `target_arch=le32`: target was removed (https://github.com/rust-lang/rust/pull/45041)
- `release`: was removed from rustfmt (https://github.com/rust-lang/rustfmt/pull/5375 and https://github.com/rust-lang/rustfmt/pull/5449)
- `dont_compile_me`: was removed from stdarch (https://github.com/rust-lang/stdarch/pull/1308)
Also made some external cfg exception mode clear and only activated for rustc and rustc tools (as to not have the Standard Library unintentionally depend on them).
Add option to include private items in library docs
I need to perform some one-off analysis on libcore, and I wanted to use the unstable JSON rustdoc output to easily do it. Unfortunately, there is currently no way to include unstable items in the library docs. This PR adds support for that, with the off-by-default `build.library-docs-private-items` setting.
Don't re-export private/unstable ArgumentV1 from `alloc`.
The `alloc::fmt::ArgumentV1` re-export was marked as `#[stable]` even though the original `core::fmt::ArgumentV1` is `#[unstable]` (and `#[doc(hidden)]`).
(It wasn't usable though:
```
error[E0658]: use of unstable library feature 'fmt_internals': internal to format_args!
--> src/main.rs:4:12
|
4 | let _: alloc::fmt::ArgumentV1 = todo!();
| ^^^^^^^^^^^^^^^^^^^^^^
|
= help: add `#![feature(fmt_internals)]` to the crate attributes to enable
```
)
Part of #99012
Prior to this PR, if the page is restored from the browser bfcache¹, we
call `switchToSavedTheme`. But `switchToSavedTheme` never looks at the
`use-system-theme` preference. Further, if it can't find a saved theme,
it will fall back to the default of "light".
For a user with cookies disabled² whose preferred color scheme is dark,
this means the theme will wobble back and forth between dark and light.
The sequence that occurs is,
1. The page is loaded. During a page load, we consult
`use-system-theme`: as cookies are disabled, this preference is
unset. The default is true.
Because the default is true, we look at the preferred color scheme:
for our example user, that's "dark". **The page theme is set to
dark.** We'll attempt to store these preferences in localStorage, but
fail due to cookies being disabled.
2. The user navigates through the docs. Subsequent page loads happen,
and the same process in step 1 recurs. Previous pages are
(potentially) put into the bfcache.
3. The user navigates backwards/forwards, causing a page in bfcache to
be pulled out of cache. The `pageShow` event handler is triggered.
However, this calls `switchToSavedTheme`: this doesn't consider the
system theme, as noted above. Instead, it only looks for a saved
theme. However, with cookies disabled, there is none. It defaults to
light. **The page theme is set to light!** The user wonders why the
dark theme is lost.
There are effectively two functions trying to determine and apply the
correct theme: `updateSystemTheme` and `switchToSavedTheme`. Thus, we
merge them into just one: `updateTheme`. This function contains all the
logic for determining the correct theme, and is called in all
circumstances where we need to set the theme:
* The initial page load
* If the browser preferred color scheme (i.e., light/dark mode) is
changed
* If the page is restored from bfcache
* If the user updates the theme preferences (i.e., in `settings.js`)
Fixes#94250.
¹bfcache: https://web.dev/bfcache/ The bfcache is used to sleep a page,
if the user navigates away from it, and to restore it from cache if the
user returns to it.
²Note that the browser preference that enables/disables cookies really
controls many forms of storage. The same preference thus also affects
localStorage. (This is so a normal browser user doesn't need to
understand the distinction between "cookies" and "localStorage".)
Currently, deriving on packed structs has some non-trivial limitations,
related to the fact that taking references on unaligned fields is UB.
The current approach to field accesses in derived code:
- Normal case: `&self.0`
- In a packed struct that derives `Copy`: `&{self.0}`
- In a packed struct that doesn't derive `Copy`: `&self.0`
Plus, we disallow deriving any builtin traits other than `Default` for any
packed generic type, because it's possible that there might be
misaligned fields. This is a fairly broad restriction.
Plus, we disallow deriving any builtin traits other than `Default` for most
packed types that don't derive `Copy`. (The exceptions are those where the
alignments inherently satisfy the packing, e.g. in a type with
`repr(packed(N))` where all the fields have alignments of `N` or less
anyway. Such types are pretty strange, because the `packed` attribute is
not having any effect.)
This commit introduces a new, simpler approach to field accesses:
- Normal case: `&self.0`
- In a packed struct: `&{self.0}`
In the latter case, this requires that all fields impl `Copy`, which is
a new restriction. This means that the following example compiles under
the old approach and doesn't compile under the new approach.
```
#[derive(Debug)]
struct NonCopy(u8);
#[derive(Debug)
#[repr(packed)]
struct MyType(NonCopy);
```
(Note that the old approach's support for cases like this was brittle.
Changing the `u8` to a `u16` would be enough to stop it working. So not
much capability is lost here.)
However, the other constraints from the old rules are removed. We can now
derive builtin traits for packed generic structs like this:
```
trait Trait { type A; }
#[derive(Hash)]
#[repr(packed)]
pub struct Foo<T: Trait>(T, T::A);
```
To allow this, we add a `T: Copy` bound in the derived impl and a `T::A:
Copy` bound in where clauses. So `T` and `T::A` must impl `Copy`.
We can now also derive builtin traits for packed structs that don't derive
`Copy`, so long as the fields impl `Copy`:
```
#[derive(Hash)]
#[repr(packed)]
pub struct Foo(u32);
```
This includes types that hand-impl `Copy` rather than deriving it, such as the
following, that show up in winapi-0.2:
```
#[derive(Clone)]
#[repr(packed)]
struct MyType(i32);
impl Copy for MyType {}
```
The new approach is simpler to understand and implement, and it avoids
the need for the `unsafe_derive_on_repr_packed` check.
One exception is required for backwards-compatibility: we allow `[u8]`
fields for now. There is a new lint for this,
`byte_slice_in_packed_struct_with_derive`.
