Auto merge of #115263 - matthiaskrgr:rollup-taqu2h0, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #114924 (coverage: Tidy up `run-coverage` tests in several small ways)
 - #114927 (CI: add more debug logging to Docker caching)
 - #114957 (tests: Fix tests for LoongArch64)
 - #115007 (Correct and expand documentation of `handle_alloc_error` and `set_alloc_error_hook`.)
 - #115098 (rust-gdbgui: remove excessive quotes)
 - #115111 (compile rust-anaylzer with `x check` if it's enabled)

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

Author: bors

library/alloc/src/alloc.rs

@@ -343,18 +343,31 @@ extern "Rust" {
     fn __rust_alloc_error_handler(size: usize, align: usize) -> !;
 }
 
-/// Abort on memory allocation error or failure.
+/// Signal a memory allocation error.
 ///
-/// Callers of memory allocation APIs wishing to abort computation
+/// Callers of memory allocation APIs wishing to cease execution
 /// in response to an allocation error are encouraged to call this function,
-/// rather than directly invoking `panic!` or similar.
+/// rather than directly invoking [`panic!`] or similar.
 ///
-/// The default behavior of this function is to print a message to standard error
-/// and abort the process.
-/// It can be replaced with [`set_alloc_error_hook`] and [`take_alloc_error_hook`].
+/// This function is guaranteed to diverge (not return normally with a value), but depending on
+/// global configuration, it may either panic (resulting in unwinding or aborting as per
+/// configuration for all panics), or abort the process (with no unwinding).
+///
+/// The default behavior is:
+///
+///  * If the binary links against `std` (typically the case), then
+///   print a message to standard error and abort the process.
+///   This behavior can be replaced with [`set_alloc_error_hook`] and [`take_alloc_error_hook`].
+///   Future versions of Rust may panic by default instead.
+///
+/// * If the binary does not link against `std` (all of its crates are marked
+///   [`#![no_std]`][no_std]), then call [`panic!`] with a message.
+///   [The panic handler] applies as to any panic.
 ///
 /// [`set_alloc_error_hook`]: ../../std/alloc/fn.set_alloc_error_hook.html
 /// [`take_alloc_error_hook`]: ../../std/alloc/fn.take_alloc_error_hook.html
+/// [The panic handler]: https://doc.rust-lang.org/reference/runtime.html#the-panic_handler-attribute
+/// [no_std]: https://doc.rust-lang.org/reference/names/preludes.html#the-no_std-attribute
 #[stable(feature = "global_alloc", since = "1.28.0")]
 #[rustc_const_unstable(feature = "const_alloc_error", issue = "92523")]
 #[cfg(all(not(no_global_oom_handling), not(test)))]

library/std/src/alloc.rs

@@ -290,15 +290,29 @@ static HOOK: AtomicPtr<()> = AtomicPtr::new(ptr::null_mut());
 
 /// Registers a custom allocation error hook, replacing any that was previously registered.
 ///
-/// The allocation error hook is invoked when an infallible memory allocation fails, before
-/// the runtime aborts. The default hook prints a message to standard error,
-/// but this behavior can be customized with the [`set_alloc_error_hook`] and
-/// [`take_alloc_error_hook`] functions.
+/// The allocation error hook is invoked when an infallible memory allocation fails — that is,
+/// as a consequence of calling [`handle_alloc_error`] — before the runtime aborts.
 ///
-/// The hook is provided with a `Layout` struct which contains information
+/// The allocation error hook is a global resource. [`take_alloc_error_hook`] may be used to
+/// retrieve a previously registered hook and wrap or discard it.
+///
+/// # What the provided `hook` function should expect
+///
+/// The hook function is provided with a [`Layout`] struct which contains information
 /// about the allocation that failed.
 ///
-/// The allocation error hook is a global resource.
+/// The hook function may choose to panic or abort; in the event that it returns normally, this
+/// will cause an immediate abort.
+///
+/// Since [`take_alloc_error_hook`] is a safe function that allows retrieving the hook, the hook
+/// function must be _sound_ to call even if no memory allocations were attempted.
+///
+/// # The default hook
+///
+/// The default hook, used if [`set_alloc_error_hook`] is never called, prints a message to
+/// standard error (and then returns, causing the runtime to abort the process).
+/// Compiler options may cause it to panic instead, and the default behavior may be changed
+/// to panicking in future versions of Rust.
 ///
 /// # Examples
 ///

src/bootstrap/check.rs

@@ -353,10 +353,17 @@ pub struct RustAnalyzer {
 impl Step for RustAnalyzer {
     type Output = ();
     const ONLY_HOSTS: bool = true;
-    const DEFAULT: bool = false;
+    const DEFAULT: bool = true;
 
     fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.path("src/tools/rust-analyzer")
+        let builder = run.builder;
+        run.path("src/tools/rust-analyzer").default_condition(
+            builder
+                .config
+                .tools
+                .as_ref()
+                .map_or(true, |tools| tools.iter().any(|tool| tool == "rust-analyzer")),
+        )
     }
 
     fn make_run(run: RunConfig<'_>) {

src/ci/docker/run.sh

@@ -64,9 +64,8 @@ if [ -f "$docker_dir/$image/Dockerfile" ]; then
 
       docker --version >> $hash_key
 
-      # Include cache version. Currently it is needed to bust Docker
-      # cache key after opting in into the old Docker build backend.
-      echo "1" >> $hash_key
+      # Include cache version. Can be used to manually bust the Docker cache.
+      echo "2" >> $hash_key
 
       cksum=$(sha512sum $hash_key | \
         awk '{print $1}')
@@ -78,6 +77,10 @@ if [ -f "$docker_dir/$image/Dockerfile" ]; then
       set +e
       retry curl --max-time 600 -y 30 -Y 10 --connect-timeout 30 -f -L -C - \
         -o /tmp/rustci_docker_cache "$url"
+
+      docker_archive_hash=$(sha512sum /tmp/rustci_docker_cache | awk '{print $1}')
+      echo "Downloaded archive hash: ${docker_archive_hash}"
+
       echo "Loading images into docker"
       # docker load sometimes hangs in the CI, so time out after 10 minutes with TERM,
       # KILL after 12 minutes
@@ -115,8 +118,10 @@ if [ -f "$docker_dir/$image/Dockerfile" ]; then
       digest=$(docker inspect rust-ci --format '{{.Id}}')
       echo "Built container $digest"
       if ! grep -q "$digest" <(echo "$loaded_images"); then
-        echo "Uploading finished image to $url"
+        echo "Uploading finished image $digest to $url"
         set +e
+        # Print image history for easier debugging of layer SHAs
+        docker history rust-ci
         docker history -q rust-ci | \
           grep -v missing | \
           xargs docker save | \
@@ -131,6 +136,7 @@ if [ -f "$docker_dir/$image/Dockerfile" ]; then
       mkdir -p "$dist"
       echo "$url" >"$info"
       echo "$digest" >>"$info"
+      cat "$info"
     fi
 elif [ -f "$docker_dir/disabled/$image/Dockerfile" ]; then
     if isCI; then

src/etc/rust-gdbgui

@@ -55,9 +55,9 @@ RUST_GDBGUI="${RUST_GDBGUI:-gdbgui}"
 
 # These arguments get passed through to GDB and make it load the
 # Rust pretty printers.
-GDB_ARGS="--directory=\"$GDB_PYTHON_MODULE_DIRECTORY\"" \
-   "-iex \"add-auto-load-safe-path $GDB_PYTHON_MODULE_DIRECTORY\"" \
-   "-iex \"set substitute-path /rustc/$RUSTC_COMMIT_HASH $RUSTC_SYSROOT/lib/rustlib/src/rust\""
+GDB_ARGS="--directory=\"$GDB_PYTHON_MODULE_DIRECTORY\" \
+   -iex \"add-auto-load-safe-path $GDB_PYTHON_MODULE_DIRECTORY\" \
+   -iex \"set substitute-path /rustc/$RUSTC_COMMIT_HASH $RUSTC_SYSROOT/lib/rustlib/src/rust\""
 
 # Finally we execute gdbgui.
 PYTHONPATH="$PYTHONPATH:$GDB_PYTHON_MODULE_DIRECTORY" \

tests/codegen/loongarch-abi/loongarch64-lp64d-abi.rs

@@ -250,11 +250,11 @@ pub struct IntDoubleInt {
     c: i32,
 }
 
-// CHECK: define void @f_int_double_int_s_arg(ptr noalias nocapture noundef dereferenceable(24) %a)
+// CHECK: define void @f_int_double_int_s_arg(ptr noalias nocapture noundef align 8 dereferenceable(24) %a)
 #[no_mangle]
 pub extern "C" fn f_int_double_int_s_arg(a: IntDoubleInt) {}
 
-// CHECK: define void @f_ret_int_double_int_s(ptr noalias nocapture noundef sret(%IntDoubleInt) dereferenceable(24) %0)
+// CHECK: define void @f_ret_int_double_int_s(ptr noalias nocapture noundef sret(%IntDoubleInt) align 8 dereferenceable(24) %_0)
 #[no_mangle]
 pub extern "C" fn f_ret_int_double_int_s() -> IntDoubleInt {
     IntDoubleInt { a: 1, b: 2., c: 3 }

tests/run-coverage-rustdoc/doctest.coverage

@@ -10,6 +10,8 @@ $DIR/auxiliary/doctest_crate.rs:
    LL|      3|}
 
 $DIR/doctest.rs:
+   LL|       |// aux-build:doctest_crate.rs
+   LL|       |
    LL|       |//! This test ensures that code from doctests is properly re-mapped.
    LL|       |//! See <https://github.com/rust-lang/rust/issues/79417> for more info.
    LL|       |//!
@@ -78,7 +80,7 @@ $DIR/doctest.rs:
    LL|       |//!     doctest_main()
    LL|       |//! }
    LL|       |//! ```
-   LL|       |// aux-build:doctest_crate.rs
+   LL|       |
    LL|       |/// doctest attached to fn testing external code:
    LL|       |/// ```
    LL|      1|/// extern crate doctest_crate;

tests/run-coverage-rustdoc/doctest.rs

@@ -1,3 +1,5 @@
+// aux-build:doctest_crate.rs
+
 //! This test ensures that code from doctests is properly re-mapped.
 //! See <https://github.com/rust-lang/rust/issues/79417> for more info.
 //!
@@ -63,7 +65,7 @@
 //!     doctest_main()
 //! }
 //! ```
-// aux-build:doctest_crate.rs
+
 /// doctest attached to fn testing external code:
 /// ```
 /// extern crate doctest_crate;

tests/run-coverage/assert.coverage

@@ -7,7 +7,7 @@
                                                   ^1
    LL|      3|}
    LL|       |
-   LL|      1|fn main() -> Result<(),u8> {
+   LL|      1|fn main() -> Result<(), u8> {
    LL|      1|    let mut countdown = 10;
    LL|     11|    while countdown > 0 {
    LL|     11|        if countdown == 1 {

tests/run-coverage/assert.rs

@@ -6,7 +6,7 @@ fn might_fail_assert(one_plus_one: u32) {
     assert_eq!(1 + 1, one_plus_one, "the argument was wrong");
 }
 
-fn main() -> Result<(),u8> {
+fn main() -> Result<(), u8> {
     let mut countdown = 10;
     while countdown > 0 {
         if countdown == 1 {