nnpack cross-compilation error for android

[knsong]

hi, when I compile nnpack for android on Ubuntu 14.04 using android-ndk-r11b, there are always errors such as:

In file included from jni/../jni/../src/psimd/2d-fourier-8x8.c:3:
/usr/include/complex.h:35:19: error: token is not a valid binary operator in a preprocessor subexpression
#if __GNUC_PREREQ (2, 7) && !__GNUC_PREREQ (2, 97)

I directly compiled nnpack without any modifications of jni/Android.mk, Application.mk using command NDK_ROOT/ndk_build in NNPACK folder.
I've googled it much but still can't find out what the problem is. Can you give me some hint? Thanks in advance!

[knsong]

Finally modified Application.mk from APP_PLATFORM := android-14 to APP_PLATFORM := android-21 solved the problem.