Platform Support page updates.

A few updates:
- Some minor wording and formatting changes.
- Remove the `cargo` column.
- Explain the columns up-front.
- Add no-wrap on the target-triple, which looks better to me.
- Minor mention on how to install support for a built-in target via rustup.

2 files changed, 198 insertions, 193 deletions

diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index 549f8b84054..683d4029306 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -1,34 +1,49 @@
-# Rust Platform Support
+# Platform Support
 
-The Rust compiler runs on, and compiles to, a great number of platforms, though
-not all platforms are equally supported. Rust's support levels are organized
-into three tiers, each with a different set of guarantees.
+<style type="text/css">
+    td code {
+        white-space: nowrap;
+    }
+</style>
 
-Platforms are identified by their "target triple" which is the string to inform
-the compiler what kind of output should be produced. The columns below indicate
-whether the corresponding component works on the specified platform.
+Support for different platforms are organized into three tiers, each with a
+different set of guarantees.
+
+Platforms are identified by their "target triple" which is the string to
+inform the compiler what kind of output should be produced. The columns in the
+tables below have the following meanings:
+
+* std:
+    * ✓ indicates the full standard library is available.
+    * \* indicates the target only supports [`no_std`] development.
+    * ? indicates the standard library support is unknown or a work-in-progress.
+* host: A ✓ indicates that `rustc` and `cargo` can run on the host platform.
+
+[`no_std`]: https://rust-embedded.github.io/book/intro/no-std.html
 
 ## Tier 1
+
 Tier 1 platforms can be thought of as "guaranteed to work".
 Specifically they will each satisfy the following requirements:
 
 * Official binary releases are provided for the platform.
 * Automated testing is set up to run tests for the platform.
-* Landing changes to the `rust-lang/rust` repository's master branch is gated on
-    tests passing.
+* Landing changes to the `rust-lang/rust` repository's master branch is gated
+  on tests passing.
 * Documentation for how to use and how to build the platform is available.
 
-target | std | rustc | cargo | notes
--------|-----|-------|-------|-------
-`i686-pc-windows-gnu` | ✓ | ✓ | ✓ | 32-bit MinGW (Windows 7+)
-`i686-pc-windows-msvc` | ✓ | ✓ | ✓ | 32-bit MSVC (Windows 7+)
-`i686-unknown-linux-gnu` | ✓ | ✓ | ✓ | 32-bit Linux (kernel 2.6.32+, glibc 2.11+)
-`x86_64-apple-darwin` | ✓ | ✓ | ✓ | 64-bit OSX (10.7+, Lion+)
-`x86_64-pc-windows-gnu` | ✓ | ✓ | ✓ | 64-bit MinGW (Windows 7+)
-`x86_64-pc-windows-msvc` | ✓ | ✓ | ✓ | 64-bit MSVC (Windows 7+)
-`x86_64-unknown-linux-gnu` | ✓ | ✓ | ✓ | 64-bit Linux (kernel 2.6.32+, glibc 2.11+)
+target | std | host | notes
+-------|-----|------|-------
+`i686-pc-windows-gnu` | ✓ | ✓ | 32-bit MinGW (Windows 7+)
+`i686-pc-windows-msvc` | ✓ | ✓ | 32-bit MSVC (Windows 7+)
+`i686-unknown-linux-gnu` | ✓ | ✓ | 32-bit Linux (kernel 2.6.32+, glibc 2.11+)
+`x86_64-apple-darwin` | ✓ | ✓ | 64-bit OSX (10.7+, Lion+)
+`x86_64-pc-windows-gnu` | ✓ | ✓ | 64-bit MinGW (Windows 7+)
+`x86_64-pc-windows-msvc` | ✓ | ✓ | 64-bit MSVC (Windows 7+)
+`x86_64-unknown-linux-gnu` | ✓ | ✓ | 64-bit Linux (kernel 2.6.32+, glibc 2.11+)
 
 ## Tier 2
+
 Tier 2 platforms can be thought of as "guaranteed to build". Automated tests
 are not run so it's not guaranteed to produce a working build, but platforms
 often work to quite a good degree and patches are always welcome!
@@ -40,183 +55,168 @@ Specifically, these platforms are required to have each of the following:
     platforms **building**. For some platforms only the standard library is
     compiled, but for others `rustc` and `cargo` are too.
 
-target | std | rustc | cargo | notes
--------|-----|-------|-------|-------
-`aarch64-apple-ios` | ✓ |  |  | ARM64 iOS
-`aarch64-fuchsia` | ✓ |  |  | ARM64 Fuchsia
-`aarch64-linux-android` | ✓ |  |  | ARM64 Android
-`aarch64-pc-windows-msvc` | ✓ |  |  | ARM64 Windows MSVC
-`aarch64-unknown-linux-gnu` | ✓ | ✓ | ✓ | ARM64 Linux (kernel 4.2, glibc 2.17)
-`aarch64-unknown-linux-musl` | ✓ |  |  | ARM64 Linux with MUSL
-`aarch64-unknown-none` | * |  |  | Bare ARM64, hardfloat
-`aarch64-unknown-none-softfloat` | * |  |  | Bare ARM64, softfloat
-`arm-linux-androideabi` | ✓ |  |  | ARMv7 Android
-`arm-unknown-linux-gnueabi` | ✓ | ✓ | ✓ | ARMv6 Linux (kernel 3.2, glibc 2.17)
-`arm-unknown-linux-gnueabihf` | ✓ | ✓ | ✓ | ARMv6 Linux, hardfloat (kernel 3.2, glibc 2.17)
-`arm-unknown-linux-musleabi` | ✓ |  |  | ARMv6 Linux with MUSL
-`arm-unknown-linux-musleabihf` | ✓ |  |  | ARMv6 Linux with MUSL, hardfloat
-`armebv7r-none-eabi` | * |  |  | Bare ARMv7-R, Big Endian
-`armebv7r-none-eabihf` | * |  |  | Bare ARMv7-R, Big Endian, hardfloat
-`armv5te-unknown-linux-gnueabi` | ✓ |  |  | ARMv5TE Linux (kernel 4.4, glibc 2.23)
-`armv5te-unknown-linux-musleabi` | ✓ |  |  | ARMv5TE Linux with MUSL
-`armv7-linux-androideabi` | ✓ |  |  | ARMv7a Android
-`armv7a-none-eabi` | * |  |  | Bare ARMv7-A
-`armv7r-none-eabi` | * |  |  | Bare ARMv7-R
-`armv7r-none-eabihf` | * |  |  | Bare ARMv7-R, hardfloat
-`armv7-unknown-linux-gnueabi` | ✓ |   |   | ARMv7 Linux (kernel 4.15, glibc 2.27)
-`armv7-unknown-linux-gnueabihf` | ✓ | ✓ | ✓ | ARMv7 Linux, hardfloat (kernel 3.2, glibc 2.17)
-`armv7-unknown-linux-musleabi` | ✓ |   |   | ARMv7 Linux, MUSL
-`armv7-unknown-linux-musleabihf` | ✓ |  |  | ARMv7 Linux with MUSL
-`asmjs-unknown-emscripten` | ✓ |  |  | asm.js via Emscripten
-`i586-pc-windows-msvc` | ✓ |  |  | 32-bit Windows w/o SSE
-`i586-unknown-linux-gnu` | ✓ |  |  | 32-bit Linux w/o SSE (kernel 4.4, glibc 2.23)
-`i586-unknown-linux-musl` | ✓ |  |  | 32-bit Linux w/o SSE, MUSL
-`i686-linux-android` | ✓ |  |  | 32-bit x86 Android
-`i686-unknown-freebsd` | ✓ | ✓ | ✓ | 32-bit FreeBSD
-`i686-unknown-linux-musl` | ✓ |  |  | 32-bit Linux with MUSL
-`mips-unknown-linux-gnu` | ✓ | ✓ | ✓ | MIPS Linux (kernel 4.4, glibc 2.23)
-`mips-unknown-linux-musl` | ✓ |  |  | MIPS Linux with MUSL
-`mips64-unknown-linux-gnuabi64` | ✓ | ✓ | ✓ | MIPS64 Linux, n64 ABI (kernel 4.4, glibc 2.23)
-`mips64-unknown-linux-muslabi64` | ✓ |  |  | MIPS64 Linux, n64 ABI, MUSL
-`mips64el-unknown-linux-gnuabi64` | ✓ | ✓ | ✓ | MIPS64 (LE) Linux, n64 ABI (kernel 4.4, glibc 2.23)
-`mips64el-unknown-linux-muslabi64` | ✓ |  |  | MIPS64 (LE) Linux, n64 ABI, MUSL
-`mipsel-unknown-linux-gnu` | ✓ | ✓ | ✓ | MIPS (LE) Linux (kernel 4.4, glibc 2.23)
-`mipsel-unknown-linux-musl` | ✓ |  |  | MIPS (LE) Linux with MUSL
-`nvptx64-nvidia-cuda` | ✓ |  |  | --emit=asm generates PTX code that [runs on NVIDIA GPUs]
-`powerpc-unknown-linux-gnu` | ✓ | ✓ | ✓ | PowerPC Linux (kernel 2.6.32, glibc 2.11)
-`powerpc64-unknown-linux-gnu` | ✓ | ✓ | ✓ | PPC64 Linux (kernel 2.6.32, glibc 2.11)
-`powerpc64le-unknown-linux-gnu` | ✓ | ✓ | ✓ | PPC64LE Linux (kernel 3.10, glibc 2.17)
-`riscv32i-unknown-none-elf` | * |  |  | Bare RISC-V (RV32I ISA)
-`riscv32imac-unknown-none-elf` | * |  |  | Bare RISC-V (RV32IMAC ISA)
-`riscv32imc-unknown-none-elf` | * |  |  | Bare RISC-V (RV32IMC ISA)
-`riscv64gc-unknown-linux-gnu` | ✓ | ✓ | ✓ | RISC-V Linux (kernel 4.20, glibc 2.29)
-`riscv64gc-unknown-none-elf` | * |  |  | Bare RISC-V (RV64IMAFDC ISA)
-`riscv64imac-unknown-none-elf` | * |  |  | Bare RISC-V (RV64IMAC ISA)
-`s390x-unknown-linux-gnu` | ✓ | ✓ | ✓ | S390x Linux (kernel 2.6.32, glibc 2.11)
-`sparc64-unknown-linux-gnu` | ✓ |  |  | SPARC Linux (kernel 4.4, glibc 2.23)
-`sparcv9-sun-solaris` | ✓ |  |  | SPARC Solaris 10/11, illumos
-`thumbv6m-none-eabi` | * |  |  | Bare Cortex-M0, M0+, M1
-`thumbv7em-none-eabi` | * |  |  | Bare Cortex-M4, M7
-`thumbv7em-none-eabihf` | * |  |  | Bare Cortex-M4F, M7F, FPU, hardfloat
-`thumbv7m-none-eabi` | * |  |  | Bare Cortex-M3
-`thumbv7neon-linux-androideabi` | ✓ |  |  | Thumb2-mode ARMv7a Android with NEON
-`thumbv7neon-unknown-linux-gnueabihf` | ✓ |  |  | Thumb2-mode ARMv7a Linux with NEON (kernel 4.4, glibc 2.23)
-`thumbv8m.base-none-eabi` | * |  |  | ARMv8-M Baseline
-`thumbv8m.main-none-eabi` | * |  |  | ARMv8-M Mainline
-`thumbv8m.main-none-eabihf` | * |  |  | ARMv8-M Baseline, hardfloat
-`wasm32-unknown-emscripten` | ✓ |  |  | WebAssembly via Emscripten
-`wasm32-unknown-unknown` | ✓ |  |  | WebAssembly
-`wasm32-wasi` | ✓ |  |  | WebAssembly with WASI
-`x86_64-apple-ios` | ✓ |  |  | 64-bit x86 iOS
-`x86_64-fortanix-unknown-sgx` | ✓ |  |  | [Fortanix ABI] for 64-bit Intel SGX
-`x86_64-fuchsia` | ✓ |  |  | 64-bit Fuchsia
-`x86_64-linux-android` | ✓ |  |  | 64-bit x86 Android
-`x86_64-rumprun-netbsd` | ✓ |  |  | 64-bit NetBSD Rump Kernel
-`x86_64-sun-solaris` | ✓ |  |  | 64-bit Solaris 10/11, illumos
-`x86_64-unknown-cloudabi` | ✓ |  |  | 64-bit CloudABI
-`x86_64-unknown-freebsd` | ✓ | ✓ | ✓ | 64-bit FreeBSD
-`x86_64-unknown-illumos` | ✓ | ✓ | ✓ | illumos
-`x86_64-unknown-linux-gnux32` | ✓ |  |  | 64-bit Linux (x32 ABI) (kernel 4.15, glibc 2.27)
-`x86_64-unknown-linux-musl` | ✓ | ✓ | ✓ | 64-bit Linux with MUSL
-`x86_64-unknown-netbsd` | ✓ | ✓ | ✓ | NetBSD/amd64
-`x86_64-unknown-redox` | ✓ |  |  | Redox OS
+target | std | host | notes
+-------|-----|------|-------
+`aarch64-apple-ios` | ✓ |  | ARM64 iOS
+`aarch64-fuchsia` | ✓ |  | ARM64 Fuchsia
+`aarch64-linux-android` | ✓ |  | ARM64 Android
+`aarch64-pc-windows-msvc` | ✓ |  | ARM64 Windows MSVC
+`aarch64-unknown-linux-gnu` | ✓ | ✓ | ARM64 Linux (kernel 4.2, glibc 2.17)
+`aarch64-unknown-linux-musl` | ✓ |  | ARM64 Linux with MUSL
+`aarch64-unknown-none` | * |  | Bare ARM64, hardfloat
+`aarch64-unknown-none-softfloat` | * |  | Bare ARM64, softfloat
+`arm-linux-androideabi` | ✓ |  | ARMv7 Android
+`arm-unknown-linux-gnueabi` | ✓ | ✓ | ARMv6 Linux (kernel 3.2, glibc 2.17)
+`arm-unknown-linux-gnueabihf` | ✓ | ✓ | ARMv6 Linux, hardfloat (kernel 3.2, glibc 2.17)
+`arm-unknown-linux-musleabi` | ✓ |  | ARMv6 Linux with MUSL
+`arm-unknown-linux-musleabihf` | ✓ |  | ARMv6 Linux with MUSL, hardfloat
+`armebv7r-none-eabi` | * |  | Bare ARMv7-R, Big Endian
+`armebv7r-none-eabihf` | * |  | Bare ARMv7-R, Big Endian, hardfloat
+`armv5te-unknown-linux-gnueabi` | ✓ |  | ARMv5TE Linux (kernel 4.4, glibc 2.23)
+`armv5te-unknown-linux-musleabi` | ✓ |  | ARMv5TE Linux with MUSL
+`armv7-linux-androideabi` | ✓ |  | ARMv7a Android
+`armv7a-none-eabi` | * |  | Bare ARMv7-A
+`armv7r-none-eabi` | * |  | Bare ARMv7-R
+`armv7r-none-eabihf` | * |  | Bare ARMv7-R, hardfloat
+`armv7-unknown-linux-gnueabi` | ✓ |   | ARMv7 Linux (kernel 4.15, glibc 2.27)
+`armv7-unknown-linux-gnueabihf` | ✓ | ✓ | ARMv7 Linux, hardfloat (kernel 3.2, glibc 2.17)
+`armv7-unknown-linux-musleabi` | ✓ |   | ARMv7 Linux, MUSL
+`armv7-unknown-linux-musleabihf` | ✓ |  | ARMv7 Linux with MUSL
+`asmjs-unknown-emscripten` | ✓ |  | asm.js via Emscripten
+`i586-pc-windows-msvc` | ✓ |  | 32-bit Windows w/o SSE
+`i586-unknown-linux-gnu` | ✓ |  | 32-bit Linux w/o SSE (kernel 4.4, glibc 2.23)
+`i586-unknown-linux-musl` | ✓ |  | 32-bit Linux w/o SSE, MUSL
+`i686-linux-android` | ✓ |  | 32-bit x86 Android
+`i686-unknown-freebsd` | ✓ | ✓ | 32-bit FreeBSD
+`i686-unknown-linux-musl` | ✓ |  | 32-bit Linux with MUSL
+`mips-unknown-linux-gnu` | ✓ | ✓ | MIPS Linux (kernel 4.4, glibc 2.23)
+`mips-unknown-linux-musl` | ✓ |  | MIPS Linux with MUSL
+`mips64-unknown-linux-gnuabi64` | ✓ | ✓ | MIPS64 Linux, n64 ABI (kernel 4.4, glibc 2.23)
+`mips64-unknown-linux-muslabi64` | ✓ |  | MIPS64 Linux, n64 ABI, MUSL
+`mips64el-unknown-linux-gnuabi64` | ✓ | ✓ | MIPS64 (LE) Linux, n64 ABI (kernel 4.4, glibc 2.23)
+`mips64el-unknown-linux-muslabi64` | ✓ |  | MIPS64 (LE) Linux, n64 ABI, MUSL
+`mipsel-unknown-linux-gnu` | ✓ | ✓ | MIPS (LE) Linux (kernel 4.4, glibc 2.23)
+`mipsel-unknown-linux-musl` | ✓ |  | MIPS (LE) Linux with MUSL
+`nvptx64-nvidia-cuda` | ✓ |  | --emit=asm generates PTX code that [runs on NVIDIA GPUs]
+`powerpc-unknown-linux-gnu` | ✓ | ✓ | PowerPC Linux (kernel 2.6.32, glibc 2.11)
+`powerpc64-unknown-linux-gnu` | ✓ | ✓ | PPC64 Linux (kernel 2.6.32, glibc 2.11)
+`powerpc64le-unknown-linux-gnu` | ✓ | ✓ | PPC64LE Linux (kernel 3.10, glibc 2.17)
+`riscv32i-unknown-none-elf` | * |  | Bare RISC-V (RV32I ISA)
+`riscv32imac-unknown-none-elf` | * |  | Bare RISC-V (RV32IMAC ISA)
+`riscv32imc-unknown-none-elf` | * |  | Bare RISC-V (RV32IMC ISA)
+`riscv64gc-unknown-linux-gnu` | ✓ | ✓ | RISC-V Linux (kernel 4.20, glibc 2.29)
+`riscv64gc-unknown-none-elf` | * |  | Bare RISC-V (RV64IMAFDC ISA)
+`riscv64imac-unknown-none-elf` | * |  | Bare RISC-V (RV64IMAC ISA)
+`s390x-unknown-linux-gnu` | ✓ | ✓ | S390x Linux (kernel 2.6.32, glibc 2.11)
+`sparc64-unknown-linux-gnu` | ✓ |  | SPARC Linux (kernel 4.4, glibc 2.23)
+`sparcv9-sun-solaris` | ✓ |  | SPARC Solaris 10/11, illumos
+`thumbv6m-none-eabi` | * |  | Bare Cortex-M0, M0+, M1
+`thumbv7em-none-eabi` | * |  | Bare Cortex-M4, M7
+`thumbv7em-none-eabihf` | * |  | Bare Cortex-M4F, M7F, FPU, hardfloat
+`thumbv7m-none-eabi` | * |  | Bare Cortex-M3
+`thumbv7neon-linux-androideabi` | ✓ |  | Thumb2-mode ARMv7a Android with NEON
+`thumbv7neon-unknown-linux-gnueabihf` | ✓ |  | Thumb2-mode ARMv7a Linux with NEON (kernel 4.4, glibc 2.23)
+`thumbv8m.base-none-eabi` | * |  | ARMv8-M Baseline
+`thumbv8m.main-none-eabi` | * |  | ARMv8-M Mainline
+`thumbv8m.main-none-eabihf` | * |  | ARMv8-M Baseline, hardfloat
+`wasm32-unknown-emscripten` | ✓ |  | WebAssembly via Emscripten
+`wasm32-unknown-unknown` | ✓ |  | WebAssembly
+`wasm32-wasi` | ✓ |  | WebAssembly with WASI
+`x86_64-apple-ios` | ✓ |  | 64-bit x86 iOS
+`x86_64-fortanix-unknown-sgx` | ✓ |  | [Fortanix ABI] for 64-bit Intel SGX
+`x86_64-fuchsia` | ✓ |  | 64-bit Fuchsia
+`x86_64-linux-android` | ✓ |  | 64-bit x86 Android
+`x86_64-rumprun-netbsd` | ✓ |  | 64-bit NetBSD Rump Kernel
+`x86_64-sun-solaris` | ✓ |  | 64-bit Solaris 10/11, illumos
+`x86_64-unknown-cloudabi` | ✓ |  | 64-bit CloudABI
+`x86_64-unknown-freebsd` | ✓ | ✓ | 64-bit FreeBSD
+`x86_64-unknown-illumos` | ✓ | ✓ | illumos
+`x86_64-unknown-linux-gnux32` | ✓ |  | 64-bit Linux (x32 ABI) (kernel 4.15, glibc 2.27)
+`x86_64-unknown-linux-musl` | ✓ | ✓ | 64-bit Linux with MUSL
+`x86_64-unknown-netbsd` | ✓ | ✓ | NetBSD/amd64
+`x86_64-unknown-redox` | ✓ |  | Redox OS
 
 [Fortanix ABI]: https://edp.fortanix.com/
 
 ## Tier 3
+
 Tier 3 platforms are those which the Rust codebase has support for, but which
 are not built or tested automatically, and may not work. Official builds are
 not available.
 
-target | std | rustc | cargo | notes
--------|-----|-------|-------|-------
-`aarch64-apple-darwin` | ? |  |  | ARM64 macOS
-`aarch64-apple-tvos` | ** |  |  | ARM64 tvOS
-`aarch64-unknown-cloudabi` | ✓ |  |  | ARM64 CloudABI
-`aarch64-unknown-freebsd` | ✓ | ✓ | ✓ | ARM64 FreeBSD
-`aarch64-unknown-hermit` | ? |  |  |
-`aarch64-unknown-netbsd` | ? |  |  |
-`aarch64-unknown-openbsd` | ✓ | ✓ | ✓ | ARM64 OpenBSD
-`aarch64-unknown-redox` | ? |  |  | ARM64 Redox OS
-`aarch64-uwp-windows-msvc` | ? |  |  |
-`aarch64-wrs-vxworks` | ? |  |  |
-`armv4t-unknown-linux-gnueabi` | ? |  |  |
-`armv6-unknown-freebsd` | ✓ | ✓ | ✓ | ARMv6 FreeBSD
-`armv6-unknown-netbsd-eabihf` | ? |  |  |
-`armv7-apple-ios` | ✓ |  |  | RMv7 iOS, Cortex-
-`armv7-unknown-cloudabi-eabihf` | ✓ |  |  | ARMv7 CloudABI, hardfloat
-`armv7-unknown-freebsd` | ✓ | ✓ | ✓ | ARMv7 FreeBSD
-`armv7-unknown-netbsd-eabihf` | ? |  |  |
-`armv7-wrs-vxworks-eabihf` | ? |  |  |
-`armv7a-none-eabihf` | * | | | ARM Cortex-A, hardfloat
-`armv7s-apple-ios` | ✓ |  |  |
-`avr-unknown-unknown` | ? |  |  | AVR
-`hexagon-unknown-linux-musl` | ? |  |  |
-`i386-apple-ios` | ✓ |  |  | 32-bit x86 iOS
-`i686-apple-darwin` | ✓ | ✓ | ✓ | 32-bit OSX (10.7+, Lion+)
-`i686-pc-windows-msvc` | ✓ |  |  | 32-bit Windows XP support
-`i686-unknown-cloudabi` | ✓ |  |  | 32-bit CloudABI
-`i686-unknown-uefi` | ? |  |  | 32-bit UEFI
-`i686-unknown-haiku` | ✓ | ✓ | ✓ | 32-bit Haiku
-`i686-unknown-netbsd` | ✓ |  |  | NetBSD/i386 with SSE2
-`i686-unknown-openbsd` | ✓ | ✓ | ✓ | 32-bit OpenBSD
-`i686-uwp-windows-gnu` | ? |  |  |
-`i686-uwp-windows-msvc` | ? |  |  |
-`i686-wrs-vxworks` | ? |  |  |
-`mips-unknown-linux-uclibc` | ✓ |  |  | MIPS Linux with uClibc
-`mipsel-unknown-linux-uclibc` | ✓ |  |  | MIPS (LE) Linux with uClibc
-`mipsel-sony-psp` | ** |  |  | MIPS (LE) Sony PlayStation Portable (PSP)
-`mipsisa32r6-unknown-linux-gnu` | ? |  |  |
-`mipsisa32r6el-unknown-linux-gnu` | ? |  |  |
-`mipsisa64r6-unknown-linux-gnuabi64` | ? |  |  |
-`mipsisa64r6el-unknown-linux-gnuabi64` | ? |  |  |
-`msp430-none-elf` | * |  |  | 16-bit MSP430 microcontrollers
-`powerpc-unknown-linux-gnuspe` | ✓ |  |  | PowerPC SPE Linux
-`powerpc-unknown-linux-musl` | ? |  |  |
-`powerpc-unknown-netbsd` | ? |  |  |
-`powerpc-wrs-vxworks` | ? |  |  |
-`powerpc-wrs-vxworks-spe` | ? |  |  |
-`powerpc64-unknown-freebsd` | ✓ | ✓ | ✓ | PPC64 FreeBSD (ELFv1 and ELFv2)
-`powerpc64-unknown-linux-musl` | ? |  |  |
-`powerpc64-wrs-vxworks` | ? |  |  |
-`powerpc64le-unknown-linux-musl` | ? |  |  |
-`sparc-unknown-linux-gnu` | ✓ |  |  | 32-bit SPARC Linux
-`sparc64-unknown-netbsd` | ✓ | ✓ |  | NetBSD/sparc64
-`sparc64-unknown-openbsd` | ? |  |  |
-`thumbv7a-pc-windows-msvc` | ? |  |  |
-`thumbv7a-uwp-windows-msvc` | ✓ |  |  |
-`thumbv7neon-unknown-linux-musleabihf` | ? |  |  | Thumb2-mode ARMv7a Linux with NEON, MUSL
-`thumbv4t-none-eabi` | * |  |  | ARMv4T T32
-`x86_64-apple-ios-macabi` | ✓ |  |  | Apple Catalyst
-`x86_64-apple-tvos` | ** | | | x86 64-bit tvOS
-`x86_64-linux-kernel` | ? |  |  | Linux kernel modules
-`x86_64-pc-solaris` | ? |  |  |
-`x86_64-pc-windows-msvc` | ✓ |  |  | 64-bit Windows XP support
-`x86_64-unknown-dragonfly` | ✓ | ✓ | ✓ | 64-bit DragonFlyBSD
-`x86_64-unknown-haiku` | ✓ | ✓ | ✓ | 64-bit Haiku
-`x86_64-unknown-hermit` | ? |  |  |
-`x86_64-unknown-hermit-kernel` | ? |  |  | HermitCore kernel
-`x86_64-unknown-l4re-uclibc` | ? |  |  |
-`x86_64-unknown-openbsd` | ✓ | ✓ | ✓ | 64-bit OpenBSD
-`x86_64-unknown-uefi` | ? |  |  |
-`x86_64-uwp-windows-gnu` | ✓ |  |  |
-`x86_64-uwp-windows-msvc` | ✓ |  |  |
-`x86_64-wrs-vxworks` | ? |  |  |
-
-
-\* These targets only support `core`, not `alloc` or `std`.
-
-\*\* These targets only support `core` or `alloc`, not `std`.
-
-? These are targets that haven't yet been documented here. If you can shed some
-  light on these platforms support, please create an issue or PR on the [Rust
-  Forge repo].
-
-But those aren't the only platforms Rust can compile to! Those are the ones with
-built-in target definitions and/or standard library support. When linking only
-to the core library, Rust can also target additional "bare metal" platforms in
-the x86, ARM, MIPS, and PowerPC families, though it may require defining custom
-target specifications to do so.
+target | std | host | notes
+-------|-----|------|-------
+`aarch64-apple-darwin` | ? |  | ARM64 macOS
+`aarch64-apple-tvos` | * |  | ARM64 tvOS
+`aarch64-unknown-cloudabi` | ✓ |  | ARM64 CloudABI
+`aarch64-unknown-freebsd` | ✓ | ✓ | ARM64 FreeBSD
+`aarch64-unknown-hermit` | ? |  |
+`aarch64-unknown-netbsd` | ? |  |
+`aarch64-unknown-openbsd` | ✓ | ✓ | ARM64 OpenBSD
+`aarch64-unknown-redox` | ? |  | ARM64 Redox OS
+`aarch64-uwp-windows-msvc` | ? |  |
+`aarch64-wrs-vxworks` | ? |  |
+`armv4t-unknown-linux-gnueabi` | ? |  |
+`armv6-unknown-freebsd` | ✓ | ✓ | ARMv6 FreeBSD
+`armv6-unknown-netbsd-eabihf` | ? |  |
+`armv7-apple-ios` | ✓ |  | RMv7 iOS, Cortex-
+`armv7-unknown-cloudabi-eabihf` | ✓ |  | ARMv7 CloudABI, hardfloat
+`armv7-unknown-freebsd` | ✓ | ✓ | ARMv7 FreeBSD
+`armv7-unknown-netbsd-eabihf` | ? |  |
+`armv7-wrs-vxworks-eabihf` | ? |  |
+`armv7a-none-eabihf` | * | | ARM Cortex-A, hardfloat
+`armv7s-apple-ios` | ✓ |  |
+`avr-unknown-unknown` | ? |  | AVR
+`hexagon-unknown-linux-musl` | ? |  |
+`i386-apple-ios` | ✓ |  | 32-bit x86 iOS
+`i686-apple-darwin` | ✓ | ✓ | 32-bit OSX (10.7+, Lion+)
+`i686-pc-windows-msvc` | ✓ |  | 32-bit Windows XP support
+`i686-unknown-cloudabi` | ✓ |  | 32-bit CloudABI
+`i686-unknown-uefi` | ? |  | 32-bit UEFI
+`i686-unknown-haiku` | ✓ | ✓ | 32-bit Haiku
+`i686-unknown-netbsd` | ✓ |  | NetBSD/i386 with SSE2
+`i686-unknown-openbsd` | ✓ | ✓ | 32-bit OpenBSD
+`i686-uwp-windows-gnu` | ? |  |
+`i686-uwp-windows-msvc` | ? |  |
+`i686-wrs-vxworks` | ? |  |
+`mips-unknown-linux-uclibc` | ✓ |  | MIPS Linux with uClibc
+`mipsel-unknown-linux-uclibc` | ✓ |  | MIPS (LE) Linux with uClibc
+`mipsel-sony-psp` | * |  | MIPS (LE) Sony PlayStation Portable (PSP)
+`mipsisa32r6-unknown-linux-gnu` | ? |  |
+`mipsisa32r6el-unknown-linux-gnu` | ? |  |
+`mipsisa64r6-unknown-linux-gnuabi64` | ? |  |
+`mipsisa64r6el-unknown-linux-gnuabi64` | ? |  |
+`msp430-none-elf` | * |  | 16-bit MSP430 microcontrollers
+`powerpc-unknown-linux-gnuspe` | ✓ |  | PowerPC SPE Linux
+`powerpc-unknown-linux-musl` | ? |  |
+`powerpc-unknown-netbsd` | ? |  |
+`powerpc-wrs-vxworks` | ? |  |
+`powerpc-wrs-vxworks-spe` | ? |  |
+`powerpc64-unknown-freebsd` | ✓ | ✓ | PPC64 FreeBSD (ELFv1 and ELFv2)
+`powerpc64-unknown-linux-musl` | ? |  |
+`powerpc64-wrs-vxworks` | ? |  |
+`powerpc64le-unknown-linux-musl` | ? |  |
+`sparc-unknown-linux-gnu` | ✓ |  | 32-bit SPARC Linux
+`sparc64-unknown-netbsd` | ✓ | ✓ | NetBSD/sparc64
+`sparc64-unknown-openbsd` | ? |  |
+`thumbv7a-pc-windows-msvc` | ? |  |
+`thumbv7a-uwp-windows-msvc` | ✓ |  |
+`thumbv7neon-unknown-linux-musleabihf` | ? |  | Thumb2-mode ARMv7a Linux with NEON, MUSL
+`thumbv4t-none-eabi` | * |  | ARMv4T T32
+`x86_64-apple-ios-macabi` | ✓ |  | Apple Catalyst
+`x86_64-apple-tvos` | * | | x86 64-bit tvOS
+`x86_64-linux-kernel` | ? |  | Linux kernel modules
+`x86_64-pc-solaris` | ? |  |
+`x86_64-pc-windows-msvc` | ✓ |  | 64-bit Windows XP support
+`x86_64-unknown-dragonfly` | ✓ | ✓ | 64-bit DragonFlyBSD
+`x86_64-unknown-haiku` | ✓ | ✓ | 64-bit Haiku
+`x86_64-unknown-hermit` | ? |  |
+`x86_64-unknown-hermit-kernel` | ? |  | HermitCore kernel
+`x86_64-unknown-l4re-uclibc` | ? |  |
+`x86_64-unknown-openbsd` | ✓ | ✓ | 64-bit OpenBSD
+`x86_64-unknown-uefi` | ? |  |
+`x86_64-uwp-windows-gnu` | ✓ |  |
+`x86_64-uwp-windows-msvc` | ✓ |  |
+`x86_64-wrs-vxworks` | ? |  |
 
 [runs on NVIDIA GPUs]: https://github.com/japaric-archived/nvptx#targets
-[Rust Forge repo]: https://github.com/rust-lang/rust-forge
diff --git a/src/doc/rustc/src/targets/built-in.md b/src/doc/rustc/src/targets/built-in.md
index 2e94ebe345a..c33b506cdae 100644
--- a/src/doc/rustc/src/targets/built-in.md
+++ b/src/doc/rustc/src/targets/built-in.md
@@ -2,9 +2,14 @@
 
 `rustc` ships with the ability to compile to many targets automatically, we
 call these "built-in" targets, and they generally correspond to targets that
-the team is supporting directly.
+the team is supporting directly. To see the list of built-in targets, you can
+run `rustc --print target-list`.
 
-To see the list of built-in targets, you can run `rustc --print target-list`,
-or look at [the API
-docs](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_target/spec/index.html#modules).
-Each module there defines a builder for a particular target.
\ No newline at end of file
+Typically, a target needs a compiled copy of the Rust standard library to
+work. If using [rustup], then check out the documentation on
+[Cross-compilation][rustup-cross] on how to download a pre-built standard
+library built by the official Rust distributions. Most targets will need a
+system linker, and possibly other things.
+
+[rustup]: https://github.com/rust-lang/rustup
+[rustup-cross]: https://github.com/rust-lang/rustup#cross-compilation