Rollup merge of #145076 - ZhongyaoChen:feature/add-tier3-riscv64a23-target, r=davidtwco

Add new Tier-3 target: riscv64a23-unknown-linux-gnu

MCP: [Tier 3 target proposal: riscv64a23-unknown-linux-gnu](https://github.com/rust-lang/compiler-team/issues/894)

Changes:

- add new target: riscv64a23-unknown-linux-gnu
- add target page

4 files changed, 44 insertions, 0 deletions

diff --git a/src/bootstrap/src/core/sanity.rs b/src/bootstrap/src/core/sanity.rs
index 4916ebbd610..099ec488397 100644
--- a/src/bootstrap/src/core/sanity.rs
+++ b/src/bootstrap/src/core/sanity.rs
@@ -34,6 +34,7 @@ pub struct Finder {
 // Targets can be removed from this list once they are present in the stage0 compiler (usually by updating the beta compiler of the bootstrap).
 const STAGE0_MISSING_TARGETS: &[&str] = &[
     "armv7a-vex-v5",
+    "riscv64a23-unknown-linux-gnu",
     // just a dummy comment so the list doesn't get onelined
     "aarch64_be-unknown-hermit",
     "aarch64_be-unknown-none-softfloat",
diff --git a/src/doc/rustc/src/SUMMARY.md b/src/doc/rustc/src/SUMMARY.md
index 8ab10add8de..e0d637a2a67 100644
--- a/src/doc/rustc/src/SUMMARY.md
+++ b/src/doc/rustc/src/SUMMARY.md
@@ -107,6 +107,7 @@
     - [riscv32imac-unknown-xous-elf](platform-support/riscv32imac-unknown-xous-elf.md)
     - [riscv64gc-unknown-linux-gnu](platform-support/riscv64gc-unknown-linux-gnu.md)
     - [riscv64gc-unknown-linux-musl](platform-support/riscv64gc-unknown-linux-musl.md)
+    - [riscv64a23-unknown-linux-gnu](platform-support/riscv64a23-unknown-linux-gnu.md)
     - [s390x-unknown-linux-gnu](platform-support/s390x-unknown-linux-gnu.md)
     - [s390x-unknown-linux-musl](platform-support/s390x-unknown-linux-musl.md)
     - [sparc-unknown-none-elf](./platform-support/sparc-unknown-none-elf.md)
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index 6c044b84a5e..22d32a29b36 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -392,6 +392,7 @@ target | std | host | notes
 [`riscv64gc-unknown-nuttx-elf`](platform-support/nuttx.md) | ✓ |  | RISC-V 64bit with NuttX
 [`riscv64gc-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | OpenBSD/riscv64
 [`riscv64imac-unknown-nuttx-elf`](platform-support/nuttx.md) | ✓ |  | RISC-V 64bit with NuttX
+[`riscv64a23-unknown-linux-gnu`](platform-support/riscv64a23-unknown-linux-gnu.md) | ✓ | ✓ | RISC-V Linux (kernel 6.8.0+, glibc 2.39)
 [`s390x-unknown-linux-musl`](platform-support/s390x-unknown-linux-musl.md) | ✓ |  | 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+
diff --git a/src/doc/rustc/src/platform-support/riscv64a23-unknown-linux-gnu.md b/src/doc/rustc/src/platform-support/riscv64a23-unknown-linux-gnu.md
new file mode 100644
index 00000000000..2cbaaa86654
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/riscv64a23-unknown-linux-gnu.md
@@ -0,0 +1,41 @@
+# `riscv64a23-unknown-linux-gnu`
+
+**Tier: 3**
+
+RISC-V target using the ratified [RVA23 Profile](https://github.com/riscv/riscv-profiles/blob/main/src/rva23-profile.adoc).
+This target will enable all mandary features of rva23u64 by default.
+
+## Target maintainers
+
+[@ZhongyaoChen](https://github.com/ZhongyaoChen)
+[@CaiWeiran](https://github.com/CaiWeiran)
+
+## Requirements
+
+This target can be sucessfully build on the following platform: ubuntu 24.04 (Linux Kernel version 6.8.0, glibc 2.39).
+
+Other platforms may work, but are not tested. Please contanct if you encounter any issues.
+
+## Building the target
+
+Tier-3 target is not distributed through `rustup`.
+
+You need to build your own Rust, the target can be build with:
+
+```bash
+./x build --target riscv64a23-unknown-linux-gnu
+```
+
+## Building Rust programs
+
+Add the toolchain:
+
+```bash
+rustup toolchain link rva23-toolchain {path-to-rust}/build/host/stage2
+```
+
+Then cross compile crates with:
+
+```bash
+RUSTFLAGS="-C linker=riscv64-linux-gnu-gcc" cargo +rva23-toolchain build --target=riscv64a23-unknown-linux-gnu
+```