…nd `#[target-feature]``

- merge error codes
- use attribute name that is incompatible in error message
- add test for conditional incompatible attribute
- add `linkage` to the allowlist

based on the module comment in
rust/compiler/rustc_target/src/spec/mod.rs

Fixes rust-lang#128280

…ssages, r=bjorn3

`#[naked]`: report incompatible attributes

tracking issue: rust-lang#90957

this is a re-implementation of rust-lang#93809 by ``@bstrie`` which was closed 2 years ago due to inactivity.

This PR takes some of the final comments into account, specifically providing a little more context in error messages, and using an allow list to determine which attributes are compatible with `#[naked]`.

Notable attributes that are incompatible with `#[naked]` are:

  * `#[inline]`
  * `#[track_caller]`
  * ~~`#[target_feature]`~~ (this is now allowed, see PR discussion)
  * `#[test]`, `#[ignore]`, `#[should_panic]`

These attributes just directly conflict with what `#[naked]` should do.

Naked functions are still important for systems programming, embedded, and operating systems, so I'd like to move them forward.

Add a README to rustbook to explain its purpose

This adds a README to the rustbook tool to help explain what it is for and how to use it.

Stabilize `is_sorted`

Closes: rust-lang#53485.

~~Question: does~~ https://github.com/rust-lang/rust/blob/8fe0c753f23e7050b87a444b6622caf4d2272d5d/compiler/rustc_lint_defs/src/builtin.rs#L1986-L1994 ~~need a new example?~~
edit: It causes a test failure and needs to be changed anyway.

``@rustbot`` label:  T-libs-api

r? libs-api

…bilee

bitwise and bytewise methods on `NonZero`

Implementation for `nonzero_bitwise`
Tracking issue rust-lang#128281
ACP rust-lang/libs-team#413

… r=jieyouxu

rustc book: document how the RUST_TARGET_PATH variable is used

based on the module comment in
rust/compiler/rustc_target/src/spec/mod.rs

Fixes rust-lang#128280