Auto merge of #131012 - GuillaumeGomez:rollup-e9ovh3a, r=GuillaumeGomez

Rollup of 5 pull requests

Successful merges:

 - #130383 (check if it's rust-lang/rust CI job in `llvm::is_ci_llvm_modified`)
 - #130416 (resolve #130122: reword 'sort-by' edge-conditions documentation)
 - #130537 (rustdoc: add doc comment to DocVisitor)
 - #130743 (Clarifications for set_nonblocking methods)
 - #131010 (extend comment in global_llvm_features regarding target-cpu=native)

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

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -536,6 +536,11 @@ pub(crate) fn global_llvm_features(
     // -Ctarget-cpu=native
     match sess.opts.cg.target_cpu {
         Some(ref s) if s == "native" => {
+            // We have already figured out the actual CPU name with `LLVMRustGetHostCPUName` and set
+            // that for LLVM, so the features implied by that CPU name will be available everywhere.
+            // However, that is not sufficient: e.g. `skylake` alone is not sufficient to tell if
+            // some of the instructions are available or not. So we have to also explicitly ask for
+            // the exact set of features available on the host, and enable all of them.
             let features_string = unsafe {
                 let ptr = llvm::LLVMGetHostCPUFeatures();
                 let features_string = if !ptr.is_null() {

library/alloc/src/slice.rs

@@ -180,10 +180,9 @@ impl<T> [T] {
     /// This sort is stable (i.e., does not reorder equal elements) and *O*(*n* \* log(*n*))
     /// worst-case.
     ///
-    /// If the implementation of [`Ord`] for `T` does not implement a [total order] the resulting
-    /// order of elements in the slice is unspecified. All original elements will remain in the
-    /// slice and any possible modifications via interior mutability are observed in the input. Same
-    /// is true if the implementation of [`Ord`] for `T` panics.
+    /// If the implementation of [`Ord`] for `T` does not implement a [total order], the function
+    /// may panic; even if the function exits normally, the resulting order of elements in the slice
+    /// is unspecified. See also the note on panicking below.
     ///
     /// When applicable, unstable sorting is preferred because it is generally faster than stable
     /// sorting and it doesn't allocate auxiliary memory. See
@@ -212,7 +211,15 @@ impl<T> [T] {
     ///
     /// # Panics
     ///
-    /// May panic if the implementation of [`Ord`] for `T` does not implement a [total order].
+    /// May panic if the implementation of [`Ord`] for `T` does not implement a [total order], or if
+    /// the [`Ord`] implementation itself panics.
+    ///
+    /// All safe functions on slices preserve the invariant that even if the function panics, all
+    /// original elements will remain in the slice and any possible modifications via interior
+    /// mutability are observed in the input. This ensures that recovery code (for instance inside
+    /// of a `Drop` or following a `catch_unwind`) will still have access to all the original
+    /// elements. For instance, if the slice belongs to a `Vec`, the `Vec::drop` method will be able
+    /// to dispose of all contained elements.
     ///
     /// # Examples
     ///
@@ -241,10 +248,9 @@ impl<T> [T] {
     /// This sort is stable (i.e., does not reorder equal elements) and *O*(*n* \* log(*n*))
     /// worst-case.
     ///
-    /// If the comparison function `compare` does not implement a [total order] the resulting order
-    /// of elements in the slice is unspecified. All original elements will remain in the slice and
-    /// any possible modifications via interior mutability are observed in the input. Same is true
-    /// if `compare` panics.
+    /// If the comparison function `compare` does not implement a [total order], the function may
+    /// panic; even if the function exits normally, the resulting order of elements in the slice is
+    /// unspecified. See also the note on panicking below.
     ///
     /// For example `|a, b| (a - b).cmp(a)` is a comparison function that is neither transitive nor
     /// reflexive nor total, `a < b < c < a` with `a = 1, b = 2, c = 3`. For more information and
@@ -263,7 +269,14 @@ impl<T> [T] {
     ///
     /// # Panics
     ///
-    /// May panic if `compare` does not implement a [total order].
+    /// May panic if `compare` does not implement a [total order], or if `compare` itself panics.
+    ///
+    /// All safe functions on slices preserve the invariant that even if the function panics, all
+    /// original elements will remain in the slice and any possible modifications via interior
+    /// mutability are observed in the input. This ensures that recovery code (for instance inside
+    /// of a `Drop` or following a `catch_unwind`) will still have access to all the original
+    /// elements. For instance, if the slice belongs to a `Vec`, the `Vec::drop` method will be able
+    /// to dispose of all contained elements.
     ///
     /// # Examples
     ///
@@ -295,10 +308,9 @@ impl<T> [T] {
     /// This sort is stable (i.e., does not reorder equal elements) and *O*(*m* \* *n* \* log(*n*))
     /// worst-case, where the key function is *O*(*m*).
     ///
-    /// If the implementation of [`Ord`] for `K` does not implement a [total order] the resulting
-    /// order of elements in the slice is unspecified. All original elements will remain in the
-    /// slice and any possible modifications via interior mutability are observed in the input. Same
-    /// is true if the implementation of [`Ord`] for `K` panics.
+    /// If the implementation of [`Ord`] for `K` does not implement a [total order], the function
+    /// may panic; even if the function exits normally, the resulting order of elements in the slice
+    /// is unspecified. See also the note on panicking below.
     ///
     /// # Current implementation
     ///
@@ -313,7 +325,15 @@ impl<T> [T] {
     ///
     /// # Panics
     ///
-    /// May panic if the implementation of [`Ord`] for `K` does not implement a [total order].
+    /// May panic if the implementation of [`Ord`] for `K` does not implement a [total order], or if
+    /// the [`Ord`] implementation or the key-function `f` panics.
+    ///
+    /// All safe functions on slices preserve the invariant that even if the function panics, all
+    /// original elements will remain in the slice and any possible modifications via interior
+    /// mutability are observed in the input. This ensures that recovery code (for instance inside
+    /// of a `Drop` or following a `catch_unwind`) will still have access to all the original
+    /// elements. For instance, if the slice belongs to a `Vec`, the `Vec::drop` method will be able
+    /// to dispose of all contained elements.
     ///
     /// # Examples
     ///
@@ -347,10 +367,9 @@ impl<T> [T] {
     /// storage to remember the results of key evaluation. The order of calls to the key function is
     /// unspecified and may change in future versions of the standard library.
     ///
-    /// If the implementation of [`Ord`] for `K` does not implement a [total order] the resulting
-    /// order of elements in the slice is unspecified. All original elements will remain in the
-    /// slice and any possible modifications via interior mutability are observed in the input. Same
-    /// is true if the implementation of [`Ord`] for `K` panics.
+    /// If the implementation of [`Ord`] for `K` does not implement a [total order], the function
+    /// may panic; even if the function exits normally, the resulting order of elements in the slice
+    /// is unspecified. See also the note on panicking below.
     ///
     /// For simple key functions (e.g., functions that are property accesses or basic operations),
     /// [`sort_by_key`](slice::sort_by_key) is likely to be faster.
@@ -369,7 +388,15 @@ impl<T> [T] {
     ///
     /// # Panics
     ///
-    /// May panic if the implementation of [`Ord`] for `K` does not implement a [total order].
+    /// May panic if the implementation of [`Ord`] for `K` does not implement a [total order], or if
+    /// the [`Ord`] implementation panics.
+    ///
+    /// All safe functions on slices preserve the invariant that even if the function panics, all
+    /// original elements will remain in the slice and any possible modifications via interior
+    /// mutability are observed in the input. This ensures that recovery code (for instance inside
+    /// of a `Drop` or following a `catch_unwind`) will still have access to all the original
+    /// elements. For instance, if the slice belongs to a `Vec`, the `Vec::drop` method will be able
+    /// to dispose of all contained elements.
     ///
     /// # Examples
     ///

library/std/src/net/tcp.rs

@@ -561,7 +561,7 @@ impl TcpStream {
 
     /// Moves this TCP stream into or out of nonblocking mode.
     ///
-    /// This will result in `read`, `write`, `recv` and `send` operations
+    /// This will result in `read`, `write`, `recv` and `send` system operations
     /// becoming nonblocking, i.e., immediately returning from their calls.
     /// If the IO operation is successful, `Ok` is returned and no further
     /// action is required. If the IO operation could not be completed and needs

library/std/src/net/udp.rs

@@ -764,7 +764,7 @@ impl UdpSocket {
 
     /// Moves this UDP socket into or out of nonblocking mode.
     ///
-    /// This will result in `recv`, `recv_from`, `send`, and `send_to`
+    /// This will result in `recv`, `recv_from`, `send`, and `send_to` system
     /// operations becoming nonblocking, i.e., immediately returning from their
     /// calls. If the IO operation is successful, `Ok` is returned and no
     /// further action is required. If the IO operation could not be completed

src/bootstrap/src/core/build_steps/llvm.rs

@@ -242,7 +242,7 @@ pub(crate) fn is_ci_llvm_available(config: &Config, asserts: bool) -> bool {
 
 /// Returns true if we're running in CI with modified LLVM (and thus can't download it)
 pub(crate) fn is_ci_llvm_modified(config: &Config) -> bool {
-    CiEnv::is_ci() && config.rust_info.is_managed_git_subrepository() && {
+    CiEnv::is_rust_lang_managed_ci_job() && config.rust_info.is_managed_git_subrepository() && {
         // We assume we have access to git, so it's okay to unconditionally pass
         // `true` here.
         let llvm_sha = detect_llvm_sha(config, true);

src/bootstrap/src/core/config/config.rs

@@ -343,6 +343,15 @@ pub struct Config {
     pub out: PathBuf,
     pub rust_info: channel::GitInfo,
 
+    pub cargo_info: channel::GitInfo,
+    pub rust_analyzer_info: channel::GitInfo,
+    pub clippy_info: channel::GitInfo,
+    pub miri_info: channel::GitInfo,
+    pub rustfmt_info: channel::GitInfo,
+    pub enzyme_info: channel::GitInfo,
+    pub in_tree_llvm_info: channel::GitInfo,
+    pub in_tree_gcc_info: channel::GitInfo,
+
     // These are either the stage0 downloaded binaries or the locally installed ones.
     pub initial_cargo: PathBuf,
     pub initial_rustc: PathBuf,
@@ -1796,6 +1805,19 @@ impl Config {
         config.omit_git_hash = omit_git_hash.unwrap_or(default);
         config.rust_info = GitInfo::new(config.omit_git_hash, &config.src);
 
+        config.cargo_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/cargo"));
+        config.rust_analyzer_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rust-analyzer"));
+        config.clippy_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/clippy"));
+        config.miri_info = GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/miri"));
+        config.rustfmt_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/rustfmt"));
+        config.enzyme_info =
+            GitInfo::new(config.omit_git_hash, &config.src.join("src/tools/enzyme"));
+        config.in_tree_llvm_info = GitInfo::new(false, &config.src.join("src/llvm-project"));
+        config.in_tree_gcc_info = GitInfo::new(false, &config.src.join("src/gcc"));
+
         // We need to override `rust.channel` if it's manually specified when using the CI rustc.
         // This is because if the compiler uses a different channel than the one specified in config.toml,
         // tests may fail due to using a different channel than the one used by the compiler during tests.

src/bootstrap/src/lib.rs

@@ -305,18 +305,15 @@ impl Build {
         #[cfg(not(unix))]
         let is_sudo = false;
 
-        let omit_git_hash = config.omit_git_hash;
-        let rust_info = GitInfo::new(omit_git_hash, &src);
-        let cargo_info = GitInfo::new(omit_git_hash, &src.join("src/tools/cargo"));
-        let rust_analyzer_info = GitInfo::new(omit_git_hash, &src.join("src/tools/rust-analyzer"));
-        let clippy_info = GitInfo::new(omit_git_hash, &src.join("src/tools/clippy"));
-        let miri_info = GitInfo::new(omit_git_hash, &src.join("src/tools/miri"));
-        let rustfmt_info = GitInfo::new(omit_git_hash, &src.join("src/tools/rustfmt"));
-        let enzyme_info = GitInfo::new(omit_git_hash, &src.join("src/tools/enzyme"));
-
-        // we always try to use git for LLVM builds
-        let in_tree_llvm_info = GitInfo::new(false, &src.join("src/llvm-project"));
-        let in_tree_gcc_info = GitInfo::new(false, &src.join("src/gcc"));
+        let rust_info = config.rust_info.clone();
+        let cargo_info = config.cargo_info.clone();
+        let rust_analyzer_info = config.rust_analyzer_info.clone();
+        let clippy_info = config.clippy_info.clone();
+        let miri_info = config.miri_info.clone();
+        let rustfmt_info = config.rustfmt_info.clone();
+        let enzyme_info = config.enzyme_info.clone();
+        let in_tree_llvm_info = config.in_tree_llvm_info.clone();
+        let in_tree_gcc_info = config.in_tree_gcc_info.clone();
 
         let initial_target_libdir_str = if config.dry_run() {
             "/dummy/lib/path/to/lib/".to_string()

src/librustdoc/visit.rs

@@ -1,11 +1,17 @@
 use crate::clean::*;
 
+/// Allows a type to traverse the cleaned ast of a crate.
+///
+/// Note that like [`rustc_ast::visit::Visitor`], but
+/// unlike [`rustc_lint::EarlyLintPass`], if you override a
+/// `visit_*` method, you will need to manually recurse into
+/// its contents.
 pub(crate) trait DocVisitor<'a>: Sized {
     fn visit_item(&mut self, item: &'a Item) {
         self.visit_item_recur(item)
     }
 
-    /// don't override!
+    /// Don't override!
     fn visit_inner_recur(&mut self, kind: &'a ItemKind) {
         match kind {
             StrippedItem(..) => unreachable!(),
@@ -46,7 +52,7 @@ pub(crate) trait DocVisitor<'a>: Sized {
         }
     }
 
-    /// don't override!
+    /// Don't override!
     fn visit_item_recur(&mut self, item: &'a Item) {
         match &item.kind {
             StrippedItem(i) => self.visit_inner_recur(&*i),
@@ -58,6 +64,7 @@ pub(crate) trait DocVisitor<'a>: Sized {
         m.items.iter().for_each(|i| self.visit_item(i))
     }
 
+    /// This is the main entrypoint of [`DocVisitor`].
     fn visit_crate(&mut self, c: &'a Crate) {
         self.visit_item(&c.module);
 

src/tools/build_helper/src/ci.rs

@@ -19,6 +19,15 @@ impl CiEnv {
     pub fn is_ci() -> bool {
         Self::current() != CiEnv::None
     }
+
+    /// Checks if running in rust-lang/rust managed CI job.
+    pub fn is_rust_lang_managed_ci_job() -> bool {
+        Self::is_ci()
+            // If both are present, we can assume it's an upstream CI job
+            // as they are always set unconditionally.
+            && std::env::var_os("CI_JOB_NAME").is_some()
+            && std::env::var_os("TOOLSTATE_REPO").is_some()
+    }
 }
 
 pub mod gha {