Auto merge of #143173 - matthiaskrgr:rollup-ieu5k05, r=matthiaskrgr

Rollup of 11 pull requests

Successful merges:

 - rust-lang/rust#142021 (Doc: clarify priority of lint level sources)
 - rust-lang/rust#142367 (Add regression test for rust-lang/rust#137857 to ensure that we generate intra doc links for extern crate items.)
 - rust-lang/rust#142641 (Generate symbols.o for proc-macros too)
 - rust-lang/rust#142889 (Clarify doc comment on unix OpenOptions)
 - rust-lang/rust#143063 (explain `ImportData::imported_module`)
 - rust-lang/rust#143088 (Improve documentation of `TagEncoding`)
 - rust-lang/rust#143135 (fix typos on some doc comments)
 - rust-lang/rust#143138 (Port `#[link_name]` to the new attribute parsing infrastructure)
 - rust-lang/rust#143155 (`librustdoc` house-keeping 🧹)
 - rust-lang/rust#143169 (Remove unused feature gates)
 - rust-lang/rust#143171 (Fix the span of trait bound modifier `[const]`)

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 110 insertions, 13 deletions

diff --git a/src/doc/rustc/src/lints/levels.md b/src/doc/rustc/src/lints/levels.md
index 18e827bd3c9..5b002b435a5 100644
--- a/src/doc/rustc/src/lints/levels.md
+++ b/src/doc/rustc/src/lints/levels.md
@@ -330,4 +330,105 @@ $
 
 This feature is used heavily by Cargo; it will pass `--cap-lints allow` when
 compiling your dependencies, so that if they have any warnings, they do not
-pollute the output of your build.
+pollute the output of your build. However, note that `--cap-lints allow` does **not** override lints marked as `force-warn`.
+
+## Priority of lint level sources
+
+Rust allows setting lint levels (`allow`, `warn`, `deny`, `forbid`, `force-warn`) through various sources:
+
+- **Attributes**: `#[allow(...)]`, `#![deny(...)]`, etc.
+- **Command-line options**: `--cap-lints`, `--force-warn`, `-A`, `-W`, `-D`, `-F`
+
+Here’s how these different lint controls interact:
+
+1. [`--force-warn`](#force-warn) forces a lint to warning level, and takes precedence over attributes and all other CLI flags.
+
+   ```rust,compile_fail
+   #[forbid(unused_variables)]
+   fn main() {
+       let x = 42;
+   }
+   ```
+
+   Compiled with:
+
+   ```bash
+    $ rustc --force-warn unused_variables lib.rs
+    warning: unused variable: `x`
+      --> lib.rs:3:9
+      |
+    3 |     let x = 42;
+      |         ^ help: if this is intentional, prefix it with an underscore: `_x`
+      |
+      = note: requested on the command line with `--force-warn unused-variables`
+
+    warning: 1 warning emitted
+   ```
+
+2. [`--cap-lints`](#capping-lints) sets the maximum level of a lint, and takes precedence over attributes as well as the `-D`, `-W`, and `-F` CLI flags.
+
+   ```rust,compile_fail
+   #[deny(unused_variables)]
+   fn main() {
+       let x = 42;
+   }
+   ```
+
+   Compiled with:
+
+   ```bash
+    $ rustc --cap-lints=warn lib.rs
+    warning: unused variable: `x`
+    --> test1.rs:3:9
+      |
+    3 |     let x = 42;
+      |         ^ help: if this is intentional, prefix it with an underscore: `_x`
+      |
+    note: the lint level is defined here
+    --> test1.rs:1:8
+      |
+    1 | #[deny(unused_variables)]
+      |        ^^^^^^^^^^^^^^^^
+
+    warning: 1 warning emitted
+   ```
+
+3. [CLI level flags](#via-compiler-flag) take precedence over attributes.
+
+   The order of the flags matter; flags on the right take precedence over earlier flags.
+
+   ```rust
+   fn main() {
+       let x = 42;
+   }
+   ```
+
+   Compiled with:
+
+   ```bash
+    $ rustc -A unused_variables -D unused_variables lib.rs
+    error: unused variable: `x`
+    --> test1.rs:2:9
+      |
+    2 |     let x = 42;
+      |         ^ help: if this is intentional, prefix it with an underscore: `_x`
+      |
+      = note: requested on the command line with `-D unused-variables`
+
+    error: aborting due to 1 previous error
+   ```
+
+4. Within the source, [attributes](#via-an-attribute) at a lower-level in the syntax tree take precedence over attributes at a higher level, or from a previous attribute on the same entity as listed in left-to-right source order.
+
+   ```rust
+   #![deny(unused_variables)]
+
+   #[allow(unused_variables)]
+   fn main() {
+       let x = 42; // Allow wins
+   }
+   ```
+
+   - The exception is once a lint is set to "forbid", it is an error to try to change its level except for `deny`, which is allowed inside a forbid context, but is ignored.
+
+In terms of priority, [lint groups](groups.md) are treated as-if they are expanded to a list of all of the lints they contain. The exception is the `warnings` group which ignores attribute and CLI order and applies to all lints that would otherwise warn within the entity.
diff --git a/src/librustdoc/Cargo.toml b/src/librustdoc/Cargo.toml
index bba8e630bcc..fdde8309cf9 100644
--- a/src/librustdoc/Cargo.toml
+++ b/src/librustdoc/Cargo.toml
@@ -8,23 +8,25 @@ build = "build.rs"
 path = "lib.rs"
 
 [dependencies]
+# tidy-alphabetical-start
 arrayvec = { version = "0.7", default-features = false }
 askama = { version = "0.14", default-features = false, features = ["alloc", "config", "derive"] }
 base64 = "0.21.7"
-itertools = "0.12"
 indexmap = "2"
+itertools = "0.12"
 minifier = { version = "0.3.5", default-features = false }
 pulldown-cmark-escape = { version = "0.11.0", features = ["simd"] }
 regex = "1"
 rustdoc-json-types = { path = "../rustdoc-json-types" }
-serde_json = "1.0"
 serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
 smallvec = "1.8.1"
 tempfile = "3"
+threadpool = "1.8.1"
 tracing = "0.1"
 tracing-tree = "0.3.0"
-threadpool = "1.8.1"
 unicode-segmentation = "1.9"
+# tidy-alphabetical-end
 
 [dependencies.tracing-subscriber]
 version = "0.3.3"
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 025c135aff2..a3cdc4f687f 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -1,8 +1,8 @@
+// tidy-alphabetical-start
 #![doc(
     html_root_url = "https://doc.rust-lang.org/nightly/",
     html_playground_url = "https://play.rust-lang.org/"
 )]
-#![feature(rustc_private)]
 #![feature(ascii_char)]
 #![feature(ascii_char_variants)]
 #![feature(assert_matches)]
@@ -11,18 +11,12 @@
 #![feature(file_buffered)]
 #![feature(format_args_nl)]
 #![feature(if_let_guard)]
-#![feature(impl_trait_in_assoc_type)]
 #![feature(iter_intersperse)]
-#![feature(never_type)]
 #![feature(round_char_boundary)]
+#![feature(rustc_private)]
 #![feature(test)]
-#![feature(type_alias_impl_trait)]
-#![feature(type_ascription)]
-#![recursion_limit = "256"]
 #![warn(rustc::internal)]
-#![allow(clippy::collapsible_if, clippy::collapsible_else_if)]
-#![allow(rustc::diagnostic_outside_of_impl)]
-#![allow(rustc::untranslatable_diagnostic)]
+// tidy-alphabetical-end
 
 extern crate thin_vec;