Recently, I've had to build a custom Android NDK toolchain from source. The steps below detail my approach. I used a fresh install of Ubuntu 12.04 64-bit in a virtual machine with 6GB of RAM and a large amount of disk space, in conjuction with NDK r9.

  1. Download the Android NDK and extract it:

    tar -xf android-ndk-r9-linux-x86_64.tar.bz2
cd android-ndk-r9

  2. Download the toolchain source code:

    ./build/tools/download-toolchain-sources.sh src

    The script will automatically download sources for the most recent NDK release (not the tip of the tree).

  3. Install the following required packages:

    sudo apt-get install g++-multilib
sudo apt-get install m4
sudo apt-get install texinfo
sudo apt-get install bison
sudo apt-get install flex
sudo apt-get install libncurses5-dev
sudo apt-get install lib32ncurses5-dev

  4. This should be enough to build the Linux version of the toolchain:

    ./build/tools/build-gcc.sh --verbose $(pwd)/src $(pwd) arm-linux-androideabi-4.6

    Depending on how powerful your machine is, the build can take anywhere from a few minutes to an hour plus.

Windows

To build the Windows version of the toolchain, a few extra steps will be needed.

  1. Install MinGW:

    sudo apt-get install curl
sudo apt-get install subversion

# Required for 32-bit
./build/tools/build-mingw64-toolchain.sh --target-arch=i686

# Required for 64-bit. The --force-build argument is not specific
# to 64-bit; it's needed to ensure the sources are actually
# built the second time the command is run.
./build/tools/build-mingw64-toolchain.sh --force-build

cp -a /tmp/build-mingw64-toolchain-$USER/install-x86_64-linux-gnu/i686-w64-mingw32 ~/
cp -a /tmp/build-mingw64-toolchain-$USER/install-x86_64-linux-gnu/x86_64-w64-mingw32 ~/

export PATH=$PATH:~/i686-w64-mingw32/bin
export PATH=$PATH:~/x86_64-w64-mingw32/bin

  2. Clone the repositories containing the necessary prebuilt items:

    # Required for 32-bit
git clone https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/host/i686-linux-glibc2.7-4.6 $(pwd)/../prebuilts/gcc/linux-x86/host/i686-linux-glibc2.7-4.6

# Required for 64-bit
git clone https://android.googlesource.com/platform/prebuilts/tools $(pwd)/../prebuilts/tools
git clone https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.7-4.6 $(pwd)/../prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.7-4.6

  3. Install the following required package:

    sudo apt-get install lib32z1-dev

  4. Now, both the 32-bit and 64-bit Windows version of the NDK toolchain can be built:

    # 32-bit
./build/tools/build-gcc.sh --verbose --mingw $(pwd)/src $(pwd) arm-linux-androideabi-4.6

# 64-bit
./build/tools/build-gcc.sh --verbose --mingw --try-64 $(pwd)/src $(pwd) arm-linux-androideabi-4.6

References: