Auto merge of #18267 - lnicola:sync-from-rust, r=lnicola

minor: Sync from downstream

18 files changed, 133 insertions, 29 deletions

diff --git a/src/doc/book b/src/doc/book
-Subproject 99cf75a5414fa8adbe3974bd0836661ca901708
+Subproject f38ce8baef98cb20229e56f1be2d50e345f1179
diff --git a/src/doc/embedded-book b/src/doc/embedded-book
-Subproject dbae36bf3f8410aa4313b3bad42e374735d48a9
+Subproject f40a8b420ec4b4505d9489965e261f1d5c28ba2
diff --git a/src/doc/nomicon b/src/doc/nomicon
-Subproject 14649f15d232d509478206ee9ed5105641aa60d
+Subproject 456b904f791751892b01282fd2757904993c4c2
diff --git a/src/doc/reference b/src/doc/reference
-Subproject 24fb2687cdbc54fa18ae4acf5d879cfceca77b2
+Subproject c64e52a3d306eac0129f3ad6c6d8806ab99ae2e
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
-Subproject c79ec345f08a1e94494cdc8c999709a90203fd8
+Subproject 8bede1b919a81ab7d0c961f6bbf68d3efa297bd
diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
-Subproject 555f3de2fa0d61c4294b74d245f1cbad6fcbf58
+Subproject 07bc9ca9eb1cd6d9fbbf758c2753b748804a134
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index 999eb9b8a7c..0ef95ba64a1 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -358,12 +358,14 @@ target | std | host | notes
 [`riscv32imc-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF
 [`riscv32imac-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF
 [`riscv32imafc-esp-espidf`](platform-support/esp-idf.md) | ✓ |  | RISC-V ESP-IDF
+[`riscv32-wrs-vxworks`](platform-support/vxworks.md) | ✓ |  |
 [`riscv64gc-unknown-hermit`](platform-support/hermit.md) | ✓ |   | RISC-V Hermit
 `riscv64gc-unknown-freebsd` |   |   | RISC-V FreeBSD
 `riscv64gc-unknown-fuchsia` |   |   | RISC-V Fuchsia
 [`riscv64gc-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | RISC-V NetBSD
 [`riscv64gc-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | OpenBSD/riscv64
 [`riscv64-linux-android`](platform-support/android.md) |   |   | RISC-V 64-bit Android
+[`riscv64-wrs-vxworks`](platform-support/vxworks.md) | ✓ |  |
 `s390x-unknown-linux-musl` |  |  | S390x Linux (kernel 3.2, musl 1.2.3)
 `sparc-unknown-linux-gnu` | ✓ |  | 32-bit SPARC Linux
 [`sparc-unknown-none-elf`](./platform-support/sparc-unknown-none-elf.md) | * |  | Bare 32-bit SPARC V7+
@@ -386,6 +388,7 @@ target | std | host | notes
 [`x86_64-unknown-hermit`](platform-support/hermit.md) | ✓ |  | x86_64 Hermit
 `x86_64-unknown-l4re-uclibc` | ? |  |
 [`x86_64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 64-bit OpenBSD
+[`x86_64-unknown-trusty`](platform-support/trusty.md) | ? |  |
 `x86_64-uwp-windows-gnu` | ✓ |  |
 `x86_64-uwp-windows-msvc` | ✓ |  |
 [`x86_64-win7-windows-msvc`](platform-support/win7-windows-msvc.md) | ✓ |   | 64-bit Windows 7 support
@@ -410,5 +413,8 @@ target | std | host | notes
 [`riscv32imafc-unknown-nuttx-elf`](platform-support/nuttx.md) | * |  | RISC-V 32bit with NuttX
 [`riscv64imac-unknown-nuttx-elf`](platform-support/nuttx.md) | * |  | RISC-V 64bit with NuttX
 [`riscv64gc-unknown-nuttx-elf`](platform-support/nuttx.md) | * |  | RISC-V 64bit with NuttX
+[`riscv32e-unknown-none-elf`](platform-support/riscv32-unknown-none-elf.md) | * |  | Bare RISC-V (RV32E ISA)
+[`riscv32em-unknown-none-elf`](platform-support/riscv32-unknown-none-elf.md) | * |  | Bare RISC-V (RV32EM ISA)
+[`riscv32emc-unknown-none-elf`](platform-support/riscv32-unknown-none-elf.md) | * |  | Bare RISC-V (RV32EMC ISA)
 
 [runs on NVIDIA GPUs]: https://github.com/japaric-archived/nvptx#targets
diff --git a/src/doc/rustc/src/platform-support/csky-unknown-linux-gnuabiv2.md b/src/doc/rustc/src/platform-support/csky-unknown-linux-gnuabiv2.md
index e72bfb8bae7..32e4f855313 100644
--- a/src/doc/rustc/src/platform-support/csky-unknown-linux-gnuabiv2.md
+++ b/src/doc/rustc/src/platform-support/csky-unknown-linux-gnuabiv2.md
@@ -80,7 +80,7 @@ cd hello_world
 ```sh
 CARGO_TARGET_CSKY_UNKNOWN_LINUX_GNUABIV2_RUNNER=${QEMU_PATH}/bin/qemu-cskyv2 -L ${TOOLCHAIN_PATH}/csky-linux-gnuabiv2/libc \
 CARGO_TARGET_CSKY_UNKNOWN_LINUX_GNUABIV2_LINKER=${TOOLCHAIN_PATH}/bin/csky-linux-gnuabiv2-gcc \
-RUSTFLAGS="-C target-features=+crt-static" \
+RUSTFLAGS="-C target-feature=+crt-static" \
 cargo +stage2 run --target csky-unknown-linux-gnuabiv2
 ```
 
diff --git a/src/doc/rustc/src/platform-support/riscv32-unknown-none-elf.md b/src/doc/rustc/src/platform-support/riscv32-unknown-none-elf.md
index 9a27a568b57..38742143c4b 100644
--- a/src/doc/rustc/src/platform-support/riscv32-unknown-none-elf.md
+++ b/src/doc/rustc/src/platform-support/riscv32-unknown-none-elf.md
@@ -35,4 +35,4 @@ Rust test-suite on this target.
 ## Cross-compilation toolchains and C code
 
 This target supports C code. If interlinking with C or C++, you may need to use
-`riscv64-unknown-elf-gcc` as a linker instead of `rust-lld`.
+`riscv32-unknown-elf-gcc` as a linker instead of `rust-lld`.
diff --git a/src/doc/rustc/src/platform-support/riscv32e-unknown-none-elf.md b/src/doc/rustc/src/platform-support/riscv32e-unknown-none-elf.md
new file mode 100644
index 00000000000..69f08774f83
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/riscv32e-unknown-none-elf.md
@@ -0,0 +1,30 @@
+# `riscv32{e,em,emc}-unknown-none-elf`
+
+**Tier: 3**
+
+Bare-metal target for RISC-V CPUs with the RV32E, RV32EM and RV32EMC ISAs.
+
+## Target maintainers
+
+* Henri Lunnikivi, <henri.lunnikivi@gmail.com>, [@hegza](https://github.com/hegza)
+
+## Requirements
+
+The target is cross-compiled, and uses static linking. No external toolchain is
+required and the default `rust-lld` linker works, but you must specify a linker
+script.
+
+## Building the target
+
+This target is included in Rust and can be installed via `rustup`.
+
+## Testing
+
+This is a cross-compiled `no-std` target, which must be run either in a
+simulator or by programming them onto suitable hardware. It is not possible to
+run the Rust test-suite on this target.
+
+## Cross-compilation toolchains and C code
+
+This target supports C code. If interlinking with C or C++, you may need to use
+`riscv32-unknown-elf-gcc` as a linker instead of `rust-lld`.
diff --git a/src/doc/rustc/src/platform-support/vxworks.md b/src/doc/rustc/src/platform-support/vxworks.md
index f1860346c8f..6aa3d8b7361 100644
--- a/src/doc/rustc/src/platform-support/vxworks.md
+++ b/src/doc/rustc/src/platform-support/vxworks.md
@@ -14,6 +14,8 @@ Target triplets available:
 - `powerpc-wrs-vxworks`
 - `powerpc64-wrs-vxworks`
 - `powerpc-wrs-vxworks-spe`
+- `riscv32-wrs-vxworks`
+- `riscv64-wrs-vxworks`
 
 ## Target maintainers
 
diff --git a/src/doc/rustdoc/src/write-documentation/documentation-tests.md b/src/doc/rustdoc/src/write-documentation/documentation-tests.md
index 7ed2e9720fe..c93893b5ada 100644
--- a/src/doc/rustdoc/src/write-documentation/documentation-tests.md
+++ b/src/doc/rustdoc/src/write-documentation/documentation-tests.md
@@ -414,11 +414,11 @@ In some cases, doctests cannot be merged. For example, if you have:
 The problem with this code is that, if you change any other doctests, it'll likely break when
 runing `rustdoc --test`, making it tricky to maintain.
 
-This is where the `standalone` attribute comes in: it tells `rustdoc` that a doctest
+This is where the `standalone_crate` attribute comes in: it tells `rustdoc` that a doctest
 should not be merged with the others. So the previous code should use it:
 
 ```rust
-//! ```standalone
+//! ```standalone_crate
 //! let location = std::panic::Location::caller();
 //! assert_eq!(location.line(), 4);
 //! ```
diff --git a/src/doc/rustdoc/src/write-documentation/linking-to-items-by-name.md b/src/doc/rustdoc/src/write-documentation/linking-to-items-by-name.md
index 1a367b8274b..5e785483402 100644
--- a/src/doc/rustdoc/src/write-documentation/linking-to-items-by-name.md
+++ b/src/doc/rustdoc/src/write-documentation/linking-to-items-by-name.md
@@ -89,8 +89,8 @@ fn Foo() {}
 
 These prefixes will be stripped when displayed in the documentation, so `[struct@Foo]` will be
 rendered as `Foo`. The following prefixes are available: `struct`, `enum`, `trait`, `union`,
-`mod`, `module`, `const`, `constant`, `fn`, `function`, `method`, `derive`, `type`, `value`,
-`macro`, `prim` or `primitive`.
+`mod`, `module`, `const`, `constant`, `fn`, `function`, `field`, `variant`, `method`, `derive`,
+`type`, `value`, `macro`, `prim` or `primitive`.
 
 You can also disambiguate for functions by adding `()` after the function name,
 or for macros by adding `!` after the macro name. The macro `!` can be followed by `()`, `{}`,
diff --git a/src/doc/unstable-book/src/compiler-flags/default-hidden-visibility.md b/src/doc/unstable-book/src/compiler-flags/default-hidden-visibility.md
deleted file mode 100644
index 579add4a9d9..00000000000
--- a/src/doc/unstable-book/src/compiler-flags/default-hidden-visibility.md
+++ /dev/null
@@ -1,12 +0,0 @@
-# `default-hidden-visibility`
-
-The tracking issue for this feature is: https://github.com/rust-lang/compiler-team/issues/656
-
-------------------------
-
-This flag can be used to override the target's
-[`default_hidden_visibility`](https://doc.rust-lang.org/beta/nightly-rustc/rustc_target/spec/struct.TargetOptions.html#structfield.default_hidden_visibility)
-setting.
-Using `-Zdefault_hidden_visibility=yes` is roughly equivalent to Clang's
-[`-fvisibility=hidden`](https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-fvisibility)
-cmdline flag.
diff --git a/src/doc/unstable-book/src/compiler-flags/default-visibility.md b/src/doc/unstable-book/src/compiler-flags/default-visibility.md
new file mode 100644
index 00000000000..ad9e5d84bba
--- /dev/null
+++ b/src/doc/unstable-book/src/compiler-flags/default-visibility.md
@@ -0,0 +1,44 @@
+# `default-visibility`
+
+The tracking issue for this feature is: https://github.com/rust-lang/rust/issues/131090
+
+------------------------
+
+This flag can be used to override the target's
+[`default_visibility`](https://doc.rust-lang.org/beta/nightly-rustc/rustc_target/spec/struct.TargetOptions.html#structfield.default_visibility)
+setting.
+
+This option only affects building of shared objects and should have no effect on executables.
+
+Visibility an be set to one of three options:
+
+* protected
+* hidden
+* interposable
+
+## Hidden visibility
+
+Using `-Zdefault-visibility=hidden` is roughly equivalent to Clang's
+[`-fvisibility=hidden`](https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-fvisibility)
+cmdline flag. Hidden symbols will not be exported from the created shared object, so cannot be
+referenced from other shared objects or from executables.
+
+## Protected visibility
+
+Using `-Zdefault-visibility=protected` will cause rust-mangled symbols to be emitted with
+"protected" visibility. This signals the compiler, the linker and the runtime linker that these
+symbols cannot be overridden by the executable or by other shared objects earlier in the load order.
+
+This will allow the compiler to emit direct references to symbols, which may improve performance. It
+also removes the need for these symbols to be resolved when a shared object built with this option
+is loaded.
+
+Using protected visibility when linking with GNU ld prior to 2.40 will result in linker errors when
+building for Linux. Other linkers such as LLD are not affected.
+
+## Interposable
+
+Using `-Zdefault-visibility=interposable` will cause symbols to be emitted with "default"
+visibility. On platforms that support it, this makes it so that symbols can be interposed, which
+means that they can be overridden by symbols with the same name from the executable or by other
+shared objects earier in the load order.
diff --git a/src/doc/unstable-book/src/compiler-flags/print-check-cfg.md b/src/doc/unstable-book/src/compiler-flags/print-check-cfg.md
index ab63c986e85..8d314aa62d4 100644
--- a/src/doc/unstable-book/src/compiler-flags/print-check-cfg.md
+++ b/src/doc/unstable-book/src/compiler-flags/print-check-cfg.md
@@ -4,23 +4,28 @@ The tracking issue for this feature is: [#125704](https://github.com/rust-lang/r
 
 ------------------------
 
-This option of the `--print` flag print the list of expected cfgs.
+This option of the `--print` flag print the list of all the expected cfgs.
 
-This is related to the `--check-cfg` flag which allows specifying arbitrary expected
+This is related to the [`--check-cfg` flag][check-cfg] which allows specifying arbitrary expected
 names and values.
 
-This print option works similarly to `--print=cfg` (modulo check-cfg specifics):
- - *check_cfg syntax*: *output of --print=check-cfg*
- - `cfg(windows)`: `windows`
- - `cfg(feature, values("foo", "bar"))`: `feature="foo"` and `feature="bar"`
- - `cfg(feature, values(none(), ""))`: `feature` and `feature=""`
- - `cfg(feature, values(any()))`: `feature=any()`
- - `cfg(feature, values())`: `feature=`
- - `cfg(any())`: `any()`
- - *nothing*: `any()=any()`
+This print option works similarly to `--print=cfg` (modulo check-cfg specifics).
+
+| `--check-cfg`                     | `--print=check-cfg`         |
+|-----------------------------------|-----------------------------|
+| `cfg(foo)`                        | `foo`                       |
+| `cfg(foo, values("bar"))`         | `foo="bar"`                 |
+| `cfg(foo, values(none(), "bar"))` | `foo` & `foo="bar"`         |
+|                                   | *check-cfg specific syntax* |
+| `cfg(foo, values(any())`          | `foo=any()`                 |
+| `cfg(foo, values())`              | `foo=`                      |
+| `cfg(any())`                      | `any()`                     |
+| *none*                            | `any()=any()`               |
 
 To be used like this:
 
 ```bash
 rustc --print=check-cfg -Zunstable-options lib.rs
 ```
+
+[check-cfg]: https://doc.rust-lang.org/nightly/rustc/check-cfg.html
diff --git a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
index 43e11b6d57d..b1c429c7676 100644
--- a/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
+++ b/src/doc/unstable-book/src/language-features/asm-experimental-arch.md
@@ -51,7 +51,10 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 | CSKY         | `reg`          | `r[0-31]`                          | `r`                  |
 | CSKY         | `freg`         | `f[0-31]`                          | `f`                  |
 | s390x        | `reg`          | `r[0-10]`, `r[12-14]`              | `r`                  |
+| s390x        | `reg_addr`     | `r[1-10]`, `r[12-14]`              | `a`                  |
 | s390x        | `freg`         | `f[0-15]`                          | `f`                  |
+| s390x        | `vreg`         | `v[0-31]`                          | Only clobbers        |
+| s390x        | `areg`         | `a[2-15]`                          | Only clobbers        |
 | Arm64EC      | `reg`          | `x[0-12]`, `x[15-22]`, `x[25-27]`, `x30` | `r`            |
 | Arm64EC      | `vreg`         | `v[0-15]`                          | `w`                  |
 | Arm64EC      | `vreg_low16`   | `v[0-15]`                          | `x`                  |
@@ -90,6 +93,8 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 | CSKY         | `freg`                          | None           | `f32`,                                  |
 | s390x        | `reg`, `reg_addr`               | None           | `i8`, `i16`, `i32`, `i64`               |
 | s390x        | `freg`                          | None           | `f32`, `f64`                            |
+| s390x        | `vreg`                          | N/A            | Only clobbers                           |
+| s390x        | `areg`                          | N/A            | Only clobbers                           |
 | Arm64EC      | `reg`                           | None           | `i8`, `i16`, `i32`, `f32`, `i64`, `f64` |
 | Arm64EC      | `vreg`                          | None           | `i8`, `i16`, `i32`, `f32`, `i64`, `f64`, <br> `i8x8`, `i16x4`, `i32x2`, `i64x1`, `f32x2`, `f64x1`, <br> `i8x16`, `i16x8`, `i32x4`, `i64x2`, `f32x4`, `f64x2` |
 
@@ -157,6 +162,8 @@ This feature tracks `asm!` and `global_asm!` support for the following architect
 | CSKY         | `r15`                                   | This is the link register. |
 | CSKY         | `r[26-30]`                              | Reserved by its ABI.       |
 | CSKY         | `r31`                                   | This is the TLS register.  |
+| s390x        | `c[0-15]`                               | Reserved by the kernel. |
+| s390x        | `a[0-1]`                                | Reserved for system use. |
 | Arm64EC      | `xzr`                                   | This is a constant zero register which can't be modified. |
 | Arm64EC      | `x18`                                   | This is an OS-reserved register. |
 | Arm64EC      | `x13`, `x14`, `x23`, `x24`, `x28`, `v[16-31]` | These are AArch64 registers that are not supported for Arm64EC. |
diff --git a/src/doc/unstable-book/src/language-features/cfg-boolean-literals.md b/src/doc/unstable-book/src/language-features/cfg-boolean-literals.md
new file mode 100644
index 00000000000..ad795ff9d9b
--- /dev/null
+++ b/src/doc/unstable-book/src/language-features/cfg-boolean-literals.md
@@ -0,0 +1,22 @@
+# `cfg_boolean_literals`
+
+The tracking issue for this feature is: [#131204]
+
+[#131204]: https://github.com/rust-lang/rust/issues/131204
+
+------------------------
+
+The `cfg_boolean_literals` feature makes it possible to use the `true`/`false`
+literal as cfg predicate. They always evaluate to true/false respectively.
+
+## Examples
+
+```rust
+#![feature(cfg_boolean_literals)]
+
+#[cfg(true)]
+const A: i32 = 5;
+
+#[cfg(all(false))]
+const A: i32 = 58 * 89;
+```