A large collection of GNU and Open Source tools which provide functionality similar to a Linux distribution on Windows.

You can find several ways on internet. You choice comfortable way on your self.

modify CYGWIN_HOME\Cygwin.bat

@echo off
set CYGWIN_ROOT=D:\cygwin64
set HOME=D:\cygwin_home
set DISPLAY=127.0.0.1:0.0

D:
chdir D:\cygwin64\bin

REM bash --login -i
start D:\cygwin64\bin\mintty.exe -i /Cygwin-Terminal.ico -

in cygwin terminal

cd $NDK_ROOT/build/tools

./make-standalone-toolchain.sh --platform=android-9 --install-dir=/development/android-toolchian --toolchain=arm-linux-androideabi-4.6 --ndk-dir=../../ --system=windows-x86_64

You can later use it directly with something like

export PATH=/tmp/my-android-toolchain/bin:$PATH
export CC=arm-linux-androideabi-gcc   # or export CC=clang
export CXX=arm-linux-androideabi-g++  # or export CXX=clang++