Add a platform support document for Android

Author: chriswailes

src/doc/rustc/src/platform-support/android.md

@@ -0,0 +1,45 @@
+# *-linux-android and *-linux-androideabi
+
+**Tier: 2**
+
+[Android] is a mobile operating system built on top of the Linux kernel.
+
+[Android]: https://source.android.com/
+
+## Target maintainers
+
+- Chris Wailes ([@chriswailes](https://github.com/chriswailes))
+- Matthew Maurer ([@maurer](https://github.com/maurer))
+- Martin Geisler ([@mgeisler](https://github.com/mgeisler))
+
+## Requirements
+
+This target is cross-compiled from a host environment. Development may be done
+from the [source tree] or using the Android NDK.
+
+[source tree]: https://source.android.com/docs/setup/build/downloading
+
+Android targets support std and generated binaries use the ELF file format.
+
+## NDK/API Update Policy
+
+Rust will support the most recent Long Term Support (LTS) Android Native
+Development Kit (NDK).  By default Rust will support all API levels supported
+by the NDK but a higher minimum API level may be required if deemed necessary.
+
+## Building the target
+
+To build Rust binaries for Android you'll need a copy of the most recent LTS
+edition of the [Android NDK].  Supported Android targets are:
+
+* aarch64-linux-android
+* arm-linux-androideabi
+* armv7-linux-androideabi
+* i686-linux-android
+* thumbv7neon-linux-androideabi
+* x86_64-linux-android
+
+[Android NDK]: https://developer.android.com/ndk/downloads
+
+A list of all supported targets can be found
+[here](https://doc.rust-lang.org/rustc/platform-support.html)