ksutcr18

HOWTO Cross compiling on Android

5W1H

What is NDK

NDK (Native Develop Toolkit) is a toolchain from Android official, originally for users who writes native C/C++ code as JNI library. It's not designed for compiling standalone programs (./a.out) and not compatible with automake/cmake etc.

What is Standalone Toolchain

"Standalone" refers to two meanings:

The program is standalone (has nothing connect to NDK, and don't need helper scripts to run it)
The toolchain is made for building standalone programs and libs, and which can used by automake etc.

(Optional) Why NDK is hard to use

By default, NDK uses android flavor directory structure when it's finding headers and libs, which is different from GNU flavor, so the compiler cannot find them. For Example:

	sudo apt-get install libmpc-dev
	sudo apt-get install libmpfr-dev
	sudo apt-get install libgmp-dev

	export LDFLAGS='-L/usr/lib/arm-linux-gnueabihf/ -L/usr/lib/gcc/arm-linux-gnueabihf/4.6/'
	export CFLAGS='-I/usr/include/arm-linux-gnueabihf/ -mfloat-abi=hard '${LDFLAGS}
	export CXXFLAGS=${CFLAGS}
	export CPPFLAGS=${CFLAGS}

	sudo ln -s /usr/lib/arm-linux-gnueabihf/crti.o /usr/lib

	#!/bin/bash

	# this script installs GCC 4.9.3
	# to use it navigate to your home directory and type:
	# sh install-gcc-4.9.3.sh

	# download and install gcc 4.9.3
	wget https://ftp.gnu.org/gnu/gcc/gcc-4.9.3/gcc-4.9.3.tar.gz
	tar xzf gcc-4.9.3.tar.gz
	cd gcc-4.9.3

	#!/bin/bash

	# current workstation architecture (values: MACOSX, MACOSX32, MACOSX64, LINUX, LINUX32, LINUX64, WIN32, WIN64)
	WORKSTATION_ACTIVE_ARCH="MACOSX"

	# android ndk (revision version, workstation arch, install prefix path)
	ANDROID_NDK_VERSION="r10e"
	ANDROID_NDK_PLATFORM="darwin"
	ANDROID_NDK_PLATFORM_ARCH="x86_64"