This class was originally added in 73b97c7
to support hiding and showing the item, because `main.js` went through all
`docblock` elements in the DOM and added toggles to them.

https://github.com/rust-lang/rust/blob/73b97c7e7c9cfac4dfa4804654b1db6ab687b589/src/librustdoc/html/static/main.js#L1856-L1867

The `item-decl` is no longer auto-hidden since
c96f86d removed it.

`item-decl` used to be called `type-decl`: that name was changed in
8b7a2dd.

The `docblock` class is no longer used for implementing toggles, since
rustdoc switched to using `<details>` elements.

Since rust-lang#88679, rustdoc doesn't load crates eagerly.
Add an explicit `extern crate` item to make sure the crate is loaded and the bug reproduces.
You can verify this fix by adding `// compile-flags: -Znormalizing-docs` and running the test.

…e, r=oli-obk

Improve error for when query is unsupported by crate

This is an improvement to the error message mentioned on rust-lang#101666.  It seems like a good idea to also add [this link to the rustc-dev-guide](https://rustc-dev-guide.rust-lang.org/query.html), if explaining the query system in detail is a concern here, but I'm unsure if there is any restrictions on adding links to error messages.

…i-obk

MirPhase: clarify that linting is not a semantic change

r? `@JakobDegen`

Use LLVM C-API to build atomic cmpxchg and fence

We don't need C++ wrappers because the LLVM C API can build these.

…est, r=notriddle

Add GUI test for notable traits element position

Fixes rust-lang#101891.

r? ``@notriddle``

…=compiler-errors

Simplify rpitit handling on lower_fn_decl

r? ```@compiler-errors```

some post-valtree cleanup

r? project-const-generics cc `@b-naber`

…decl, r=GuillaumeGomez

rustdoc: remove `docblock` class from `item-decl`

This class was originally added in 73b97c7 to support hiding and showing the item, because `main.js` went through all `docblock` elements in the DOM and added toggles to them.

https://github.com/rust-lang/rust/blob/73b97c7e7c9cfac4dfa4804654b1db6ab687b589/src/librustdoc/html/static/main.js#L1856-L1867

The `item-decl` is no longer auto-hidden since c96f86d removed it.

`item-decl` used to be called `type-decl`: that name was changed in 8b7a2dd.

The `docblock` class is no longer used for implementing toggles, since rustdoc switched to using `<details>` elements.

Preview: https://notriddle.com/notriddle-rustdoc-test/docblock-item-decl/rustdoc/clean/types/enum.Type.html

…ompiler-errors

Make the `normalize-overflow` rustdoc test actually do something

Since rust-lang#88679, rustdoc doesn't load crates eagerly. Add an explicit `extern crate` item to make sure the crate is loaded and the bug reproduces.
You can verify this fix by adding `// compile-flags: -Znormalize-docs` and running the test to make sure it gives an error.