Auto merge of #2944 - oli-obk:rustup, r=oli-obk

Rustup

11 files changed, 184 insertions, 54 deletions

diff --git a/src/doc/book b/src/doc/book
-Subproject 8fa6b854d515506d825390fe0d817f5ef0c8935
+Subproject 21cf840842bdf768a798869f06373c96c1cc512
diff --git a/src/doc/nomicon b/src/doc/nomicon
-Subproject b5f018fb5930cb733b0a8aaf2eed975d4771e74
+Subproject c369e4b489332f8721fbae630354fa83385d457
diff --git a/src/doc/reference b/src/doc/reference
-Subproject 553d99b02a53b4133a40d5bd2e19958c67487c0
+Subproject 5ca365eac678cb0d41a20b3204546d6ed70c717
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
-Subproject 8ee9528b72b927cff8fd32346db8bbd1198816f
+Subproject 57636d6926762861f34e030d52ca25a71e95e5b
diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
-Subproject f1e637883fafeb83bdd5906ee7f467e4d35b733
+Subproject 17fe3e948498c50e208047a750f17d6a8d89669
diff --git a/src/doc/rustc/src/SUMMARY.md b/src/doc/rustc/src/SUMMARY.md
index 1e17a90a842..f8af26326a7 100644
--- a/src/doc/rustc/src/SUMMARY.md
+++ b/src/doc/rustc/src/SUMMARY.md
@@ -40,6 +40,7 @@
     - [riscv32imac-unknown-xous-elf](platform-support/riscv32imac-unknown-xous-elf.md)
     - [*-pc-windows-gnullvm](platform-support/pc-windows-gnullvm.md)
     - [\*-nto-qnx-\*](platform-support/nto-qnx.md)
+    - [\*-unknown-netbsd\*](platform-support/netbsd.md)
     - [*-unknown-openbsd](platform-support/openbsd.md)
     - [\*-unknown-uefi](platform-support/unknown-uefi.md)
     - [wasm64-unknown-unknown](platform-support/wasm64-unknown-unknown.md)
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index 62f628f8229..6d1729e57b1 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -224,13 +224,14 @@ target | std | host | notes
 `aarch64-unknown-freebsd` | ✓ | ✓ | ARM64 FreeBSD
 `aarch64-unknown-hermit` | ✓ |  | ARM64 HermitCore
 `aarch64-unknown-linux-gnu_ilp32` | ✓ | ✓ | ARM64 Linux (ILP32 ABI)
-`aarch64-unknown-netbsd` | ✓ | ✓ |
+[`aarch64-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | ARM64 NetBSD
 [`aarch64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | ARM64 OpenBSD
 `aarch64-unknown-redox` | ? |  | ARM64 Redox OS
 `aarch64-uwp-windows-msvc` | ? |  |
 `aarch64-wrs-vxworks` | ? |  |
 `aarch64_be-unknown-linux-gnu_ilp32` | ✓ | ✓ | ARM64 Linux (big-endian, ILP32 ABI)
 `aarch64_be-unknown-linux-gnu` | ✓ | ✓ | ARM64 Linux (big-endian)
+[`aarch64_be-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | ARM64 NetBSD (big-endian)
 [`arm64_32-apple-watchos`](platform-support/apple-watchos.md) | ✓ | | ARM Apple WatchOS 64-bit with 32-bit pointers
 [`armeb-unknown-linux-gnueabi`](platform-support/armeb-unknown-linux-gnueabi.md) | ✓ | ? | ARM BE8 the default ARM big-endian architecture since [ARMv6](https://developer.arm.com/documentation/101754/0616/armlink-Reference/armlink-Command-line-Options/--be8?lang=en).
 `armv4t-none-eabi` | * |  | ARMv4T A32
@@ -238,7 +239,7 @@ target | std | host | notes
 [`armv5te-none-eabi`](platform-support/armv5te-none-eabi.md) | * | | ARMv5TE A32
 `armv5te-unknown-linux-uclibceabi` | ? |  | ARMv5TE Linux with uClibc
 `armv6-unknown-freebsd` | ✓ | ✓ | ARMv6 FreeBSD
-`armv6-unknown-netbsd-eabihf` | ? |  |
+[`armv6-unknown-netbsd-eabihf`](platform-support/netbsd.md) | ✓ | ✓ | ARMv6 NetBSD w/hard-float
 [`armv6k-nintendo-3ds`](platform-support/armv6k-nintendo-3ds.md) | ? |  | ARMv6K Nintendo 3DS, Horizon (Requires devkitARM toolchain)
 `armv7-apple-ios` | ✓ |  | ARMv7 iOS, Cortex-a8
 [`armv7-sony-vita-newlibeabihf`](platform-support/armv7-sony-vita-newlibeabihf.md) | ? |  | ARM Cortex-A9 Sony PlayStation Vita (requires VITASDK toolchain)
@@ -246,7 +247,7 @@ target | std | host | notes
 [`armv7-unknown-linux-uclibceabi`](platform-support/armv7-unknown-linux-uclibceabi.md) | ✓ | ✓ | ARMv7 Linux with uClibc, softfloat
 [`armv7-unknown-linux-uclibceabihf`](platform-support/armv7-unknown-linux-uclibceabihf.md) | ✓ | ? | ARMv7 Linux with uClibc, hardfloat
 `armv7-unknown-freebsd` | ✓ | ✓ | ARMv7 FreeBSD
-`armv7-unknown-netbsd-eabihf` | ✓ | ✓ |
+[`armv7-unknown-netbsd-eabihf`](platform-support/netbsd.md) | ✓ | ✓ | ARMv7 NetBSD w/hard-float
 `armv7-wrs-vxworks-eabihf` | ? |  |
 [`armv7a-kmc-solid_asp3-eabi`](platform-support/kmc-solid.md) | ✓ |  | ARM SOLID with TOPPERS/ASP3
 [`armv7a-kmc-solid_asp3-eabihf`](platform-support/kmc-solid.md) | ✓ |  | ARM SOLID with TOPPERS/ASP3, hardfloat
@@ -262,7 +263,7 @@ target | std | host | notes
 `i686-apple-darwin` | ✓ | ✓ | 32-bit macOS (10.7+, Lion+)
 `i686-pc-windows-msvc` | * |  | 32-bit Windows XP support
 `i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku
-`i686-unknown-netbsd` | ✓ | ✓ | NetBSD/i386 with SSE2
+[`i686-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | NetBSD/i386 with SSE2
 [`i686-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | 32-bit OpenBSD
 `i686-uwp-windows-gnu` | ? |  |
 `i686-uwp-windows-msvc` | ? |  |
@@ -283,7 +284,7 @@ target | std | host | notes
 `msp430-none-elf` | * |  | 16-bit MSP430 microcontrollers
 `powerpc-unknown-linux-gnuspe` | ✓ |  | PowerPC SPE Linux
 `powerpc-unknown-linux-musl` | ? |  |
-`powerpc-unknown-netbsd` | ✓ | ✓ |
+[`powerpc-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | NetBSD 32-bit powerpc systems
 `powerpc-unknown-openbsd` | ? |  |
 `powerpc-wrs-vxworks-spe` | ? |  |
 `powerpc-wrs-vxworks` | ? |  |
@@ -307,7 +308,7 @@ target | std | host | notes
 [`riscv64gc-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | OpenBSD/riscv64
 `s390x-unknown-linux-musl` |  |  | S390x Linux (kernel 3.2, MUSL)
 `sparc-unknown-linux-gnu` | ✓ |  | 32-bit SPARC Linux
-`sparc64-unknown-netbsd` | ✓ | ✓ | NetBSD/sparc64
+[`sparc64-unknown-netbsd`](platform-support/netbsd.md) | ✓ | ✓ | NetBSD/sparc64
 [`sparc64-unknown-openbsd`](platform-support/openbsd.md) | ✓ | ✓ | OpenBSD/sparc64
 `thumbv4t-none-eabi` | * |  | ARMv4T T32
 [`thumbv5te-none-eabi`](platform-support/armv5te-none-eabi.md) | * | | ARMv5TE T32
diff --git a/src/doc/rustc/src/platform-support/esp-idf.md b/src/doc/rustc/src/platform-support/esp-idf.md
index 4bbe35709b0..8f630fa152c 100644
--- a/src/doc/rustc/src/platform-support/esp-idf.md
+++ b/src/doc/rustc/src/platform-support/esp-idf.md
@@ -13,10 +13,12 @@ Targets for the [ESP-IDF](https://github.com/espressif/esp-idf) development fram
 
 The target names follow this format: `$ARCH-esp-espidf`, where `$ARCH` specifies the target processor architecture. The following targets are currently defined:
 
-|          Target name           | Target CPU(s)         | Minimum ESP-IDF version |
-|--------------------------------|-----------------------|-------------------------|
-| `riscv32imc-esp-espidf`        |  [ESP32-C3](https://www.espressif.com/en/products/socs/esp32-c3)             | `v4.3`                |
-| `riscv32imac-esp-espidf`       |  [ESP32-C6](https://www.espressif.com/en/products/socs/esp32-c6)             | `v5.1`                |
+| Target name              | Target CPU(s)                                                   | Minimum ESP-IDF version |
+| ------------------------ | --------------------------------------------------------------- | ----------------------- |
+| `riscv32imc-esp-espidf`  | [ESP32-C2](https://www.espressif.com/en/products/socs/esp32-c2) | `v5.0`                  |
+| `riscv32imc-esp-espidf`  | [ESP32-C3](https://www.espressif.com/en/products/socs/esp32-c3) | `v4.3`                  |
+| `riscv32imac-esp-espidf` | [ESP32-C6](https://www.espressif.com/en/products/socs/esp32-c6) | `v5.1`                  |
+| `riscv32imac-esp-espidf` | [ESP32-H2](https://www.espressif.com/en/products/socs/esp32-h2) | `v5.1`                  |
 
 It is recommended to use the latest ESP-IDF stable release if possible.
 
diff --git a/src/doc/rustc/src/platform-support/loongarch-linux.md b/src/doc/rustc/src/platform-support/loongarch-linux.md
index 999e71f8028..17e85590f2c 100644
--- a/src/doc/rustc/src/platform-support/loongarch-linux.md
+++ b/src/doc/rustc/src/platform-support/loongarch-linux.md
@@ -28,9 +28,9 @@ While the integer base ABI is implied by the machine field, the floating po
 
 ## Target maintainers
 
-- [ZHAI Xiaojuan](https://github.com/zhaixiaojuan) `zhaixiaojuan@loongson.cn`
 - [WANG Rui](https://github.com/heiher) `wangrui@loongson.cn`
 - [ZHAI Xiang](https://github.com/xiangzhai) `zhaixiang@loongson.cn`
+- [ZHAI Xiaojuan](https://github.com/zhaixiaojuan) `zhaixiaojuan@loongson.cn`
 - [WANG Xuerui](https://github.com/xen0n) `git@xen0n.name`
 
 ## Requirements
diff --git a/src/doc/rustc/src/platform-support/netbsd.md b/src/doc/rustc/src/platform-support/netbsd.md
new file mode 100644
index 00000000000..a1969524a20
--- /dev/null
+++ b/src/doc/rustc/src/platform-support/netbsd.md
@@ -0,0 +1,107 @@
+# \*-unknown-netbsd
+
+**Tier: 3**
+
+[NetBSD] multi-platform 4.4BSD-based UNIX-like operating system.
+
+[NetBSD]: https://www.NetBSD.org/
+
+The target names follow this format: `$ARCH-unknown-netbsd{-$SUFFIX}`,
+where `$ARCH` specifies the target processor architecture and
+`-$SUFFIX` (optional) might indicate the ABI. The following targets
+are currently defined running NetBSD:
+
+|          Target name           | NetBSD Platform |
+|--------------------------------|-----------------|
+| `amd64-unknown-netbsd`         | [amd64 / x86_64 systems](https://wiki.netbsd.org/ports/amd64/) |
+| `armv7-unknown-netbsd-eabihf`  | [32-bit ARMv7 systems with hard-float](https://wiki.netbsd.org/ports/evbarm/) |
+| `armv6-unknown-netbsd-eabihf`  | [32-bit ARMv6 systems with hard-float](https://wiki.netbsd.org/ports/evbarm/) |
+| `aarch64-unknown-netbsd`       | [64-bit ARM systems, little-endian](https://wiki.netbsd.org/ports/evbarm/) |
+| `aarch64_be-unknown-netbsd`    | [64-bit ARM systems, big-endian](https://wiki.netbsd.org/ports/evbarm/) |
+| `i586-unknown-netbsd`          | [32-bit i386, restricted to Pentium](https://wiki.netbsd.org/ports/i386/) |
+| `i686-unknown-netbsd`          | [32-bit i386 with SSE](https://wiki.netbsd.org/ports/i386/) |
+| `mipsel-unknown-netbsd`        | [32-bit mips, requires mips32 cpu support](https://wiki.netbsd.org/ports/evbmips/) |
+| `powerpc-unknown-netbsd`       | [Various 32-bit PowerPC systems, e.g. MacPPC](https://wiki.netbsd.org/ports/macppc/) |
+| `sparc64-unknown-netbsd`       | [Sun UltraSPARC systems](https://wiki.netbsd.org/ports/sparc64/) |
+
+All use the "native" `stdc++` library which goes along with the natively
+supplied GNU C++ compiler for the given OS version.  Many of the bootstraps
+are built for NetBSD 9.x, although some exceptions exist (some
+are built for NetBSD 8.x but also work on newer OS versions).
+
+
+## Designated Developers
+
+- [@he32](https://github.com/he32), `he@NetBSD.org`
+- [NetBSD/pkgsrc-wip's rust](https://github.com/NetBSD/pkgsrc-wip/blob/master/rust/Makefile) maintainer (see MAINTAINER variable). This package is part of "pkgsrc work-in-progress" and is used for deployment and testing of new versions of rust
+- [NetBSD's pkgsrc lang/rust](https://github.com/NetBSD/pkgsrc/tree/trunk/lang/rust) for the "proper" package in pkgsrc.
+- [NetBSD's pkgsrc lang/rust-bin](https://github.com/NetBSD/pkgsrc/tree/trunk/lang/rust-bin) which re-uses the bootstrap kit as a binary distribution and therefore avoids the rather protracted native build time of rust itself
+
+Fallback to pkgsrc-users@NetBSD.org, or fault reporting via NetBSD's
+bug reporting system.
+
+## Requirements
+
+The `amd64-unknown-netbsd` artifacts is being distributed by the
+rust project.
+
+The other targets are built by the designated developers (see above),
+and the targets are initially cross-compiled, but many if not most
+of them are also built natively as part of testing.
+
+
+## Building
+
+The default build mode for the packages is a native build.
+
+
+## Cross-compilation
+
+These targets can be cross-compiled, and we do that via the pkgsrc
+package(s).
+
+Cross-compilation typically requires the "tools" and "dest" trees
+resulting from a normal cross-build of NetBSD itself, ref. our main
+build script, `build.sh`.
+
+See e.g. [do-cross.mk
+Makefile](https://github.com/NetBSD/pkgsrc/tree/trunk/lang/rust/do-cross.mk)
+for the Makefile used to cross-build all the above NetBSD targets
+(except for the `amd64` target).
+
+The major option for the rust build is whether to build rust with
+the LLVM rust carries in its distribution, or use the LLVM package
+installed from pkgsrc.  The `PKG_OPTIONS.rust` option is
+`rust-internal-llvm`, ref.  [the rust package's options.mk make
+fragment](https://github.com/NetBSD/pkgsrc/blob/trunk/lang/rust/options.mk).
+It defaults to being set for a few of the above platforms, for
+various reasons (see comments), but is otherwise unset and therefore
+indicates use of the pkgsrc LLVM.
+
+
+## Testing
+
+The Rust testsuite could presumably be run natively.
+
+For the systems where the maintainer can build natively, the rust
+compiler itself is re-built natively.  This involves the rust compiler
+being re-built with the newly self-built rust compiler, so excercises
+the result quite extensively.
+
+Additionally, for some systems we build `librsvg`, and for the more
+capable systems we build and test `firefox` (amd64, i386, aarch64).
+
+
+## Building Rust programs
+
+Rust ships pre-compiled artifacts for the `amd64-unknown-netbsd`
+target.
+
+For the other systems mentioned above, using the `pkgsrc` route is
+probably the easiest, possibly via the `rust-bin` package to save
+time, see the `RUST_TYPE` variable from the `rust.mk` Makefile
+fragment.
+
+The pkgsrc rust package has a few files to assist with building
+pkgsrc packages written in rust, ref. the `rust.mk` and `cargo.mk`
+Makefile fragments in the `lang/rust` package.
diff --git a/src/doc/style-guide/src/statements.md b/src/doc/style-guide/src/statements.md
index 62a5a032f07..9bc521e1c7b 100644
--- a/src/doc/style-guide/src/statements.md
+++ b/src/doc/style-guide/src/statements.md
@@ -103,22 +103,69 @@ let Foo {
 
 #### else blocks (let-else statements)
 
-If a let statement contains an `else` component, also known as a let-else statement,
-then the `else` component should be formatted according to the same rules as the `else` block
-in [control flow expressions (i.e. if-else, and if-let-else expressions)](./expressions.md#control-flow-expressions).
-Apply the same formatting rules to the components preceding
-the `else` block (i.e. the `let pattern: Type = initializer_expr ...` portion)
-as described [above](#let-statements)
-
-Similarly to if-else expressions, if the initializer
-expression is multi-lined, then the `else` keyword and opening brace of the block (i.e. `else {`)
-should be put on the same line as the end of the initializer
-expression with a preceding space if all the following are true:
+A let statement can contain an `else` component, making it a let-else statement.
+In this case, always apply the same formatting rules to the components preceding
+the `else` block (i.e. the `let pattern: Type = initializer_expr` portion)
+as described [for other let statements](#let-statements).
+
+The entire let-else statement may be formatted on a single line if all the
+following are true:
+
+* the entire statement is *short*
+* the `else` block contains only a single-line expression and no statements
+* the `else` block contains no comments
+* the let statement components preceding the `else` block can be formatted on a single line
+
+```rust
+let Some(1) = opt else { return };
+```
+
+Formatters may allow users to configure the value of the threshold
+used to determine whether a let-else statement is *short*.
+
+Otherwise, the let-else statement requires some line breaks.
+
+If breaking a let-else statement across multiple lines, never break between the
+`else` and the `{`, and always break before the `}`.
+
+If the let statement components preceding the `else` can be formatted on a
+single line, but the let-else does not qualify to be placed entirely on a
+single line, put the `else {` on the same line as the initializer expression,
+with a space between them, then break the line after the `{`. Indent the
+closing `}` to match the `let`, and indent the contained block one step
+further.
+
+```rust
+let Some(1) = opt else {
+    return;
+};
+
+let Some(1) = opt else {
+    // nope
+    return
+};
+```
+
+If the let statement components preceding the `else` can be formatted on a
+single line, but the `else {` does not fit on the same line, break the line
+before the `else`.
+
+```rust
+    let Some(x) = some_really_really_really_really_really_really_really_really_really_long_name
+    else {
+        return;
+    };
+```
+
+If the initializer expression is multi-line, the `else` keyword and opening
+brace of the block (i.e. `else {`) should be put on the same line as the end of
+the initializer expression, with a space between them, if all the following are
+true:
 
 * The initializer expression ends with one or more closing
   parentheses, square brackets, and/or braces
 * There is nothing else on that line
-* That line is not indented beyond the indent of the first line containing the `let` keyword
+* That line has the same indentation level as the initial `let` keyword.
 
 For example:
 
@@ -135,7 +182,9 @@ let Some(x) = y.foo(
 }
 ```
 
-Otherwise, the `else` keyword and opening brace should be placed on the next line after the end of the initializer expression, and should not be indented (the `else` keyword should be aligned with the `let` keyword).
+Otherwise, the `else` keyword and opening brace should be placed on the next
+line after the end of the initializer expression, and the `else` keyword should
+have the same indentation level as the `let` keyword.
 
 For example:
 
@@ -155,11 +204,6 @@ fn main() {
         return
     };
 
-    let Some(x) = some_really_really_really_really_really_really_really_really_really_long_name
-    else {
-        return;
-    };
-
     let Some(aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa) =
         bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
     else {
@@ -168,31 +212,6 @@ fn main() {
 }
 ```
 
-##### Single line let-else statements
-
-The entire let-else statement may be formatted on a single line if all the following are true:
-
-* the entire statement is *short*
-* the `else` block contains a single-line expression and no statements
-* the `else` block contains no comments
-* the let statement components preceding the `else` block can be formatted on a single line
-
-```rust
-let Some(1) = opt else { return };
-
-let Some(1) = opt else {
-    return;
-};
-
-let Some(1) = opt else {
-    // nope
-    return
-};
-```
-
-Formatters may allow users to configure the value of the threshold
-used to determine whether a let-else statement is *short*.
-
 ### Macros in statement position
 
 A macro use in statement position should use parentheses or square brackets as