$ ./ndk-build -C samples/hello-jni
D:android_sdk_windowsandroid-ndk-r7prebuiltwindowsinawk.exe: can't open file /cygdrive/d/android_sdk_windows/android-ndk-r7/build/awk/check-awk.awk
source line number 1 source file /cygdrive/d/android_sdk_windows/android-ndk-r7/build/awk/check-awk.awk
context is
>>> <<<
Android NDK: Host 'awk' tool is outdated. Please define HOST_AWK to point to Gawk or Nawk !
make: 进入目录“/cygdrive/d/android_sdk_windows/android-ndk-r7/samples/hello-jni”
/cygdrive/d/android_sdk_windows/android-ndk-r7/build/core/init.mk:258: *** Android NDK: Aborting. 。 停止。
make: 离开目录“/cygdrive/d/android_sdk_windows/android-ndk-r7/samples/hello-jni”
日志提示是awk过期，这是因为NDK自带的awk.exe程序过期，把它删除，使用aygwin的awk工具就好了。
解决方法：直接删除android-ndk-r7prebuiltwindowsinawk.exe文件