安卓如何编译生成arm64-v8a的so文件，试了很多次都报错

[h3clikejava]

用的libncnn.a文件是直接从github上下的ncnn-android-lib/arm64-v8a/libncnn.a
然后和armeabi-v7a一样的方法，进入到工程的jni文件夹下ndk-build。

然后报错：
h3c-macbook:jni H3c$ ndk-build
[armeabi-v7a] SharedLibrary : libsqueezencnn.so
/Users/H3c/Documents/sdk/android-ndk-r16b/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld: error: /Users/H3c/Downloads/ncnn-android-lib-4/arm64-v8a/libncnn.a(mat.cpp.o): incompatible target
/Users/H3c/Documents/sdk/android-ndk-r16b/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld: error: /Users/H3c/Downloads/ncnn-android-lib-4/arm64-v8a/libncnn.a(mat_pixel.cpp.o): incompatible target
/Users/H3c/Documents/sdk/android-ndk-r16b/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.9.x/../../../../arm-linux-androideabi/bin/ld: error: /Users/H3c/Downloads/ncnn-android-lib-4/arm64-v8a/libncnn.a(net.cpp.o): incompatible target
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:81: error: undefined reference to 'ncnn::Net::load_param(unsigned char const*)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:90: error: undefined reference to 'ncnn::Net::load_model(unsigned char const*)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:126: error: undefined reference to 'ncnn::Mat::from_pixels(unsigned char const*, int, int, int)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:142: error: undefined reference to 'ncnn::Mat::substract_mean_normalize(float const*, float const*)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:144: error: undefined reference to 'ncnn::Net::create_extractor() const'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:146: error: undefined reference to 'ncnn::Extractor::set_num_threads(int)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:150: error: undefined reference to 'ncnn::Extractor::input(int, ncnn::Mat const&)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:151: error: undefined reference to 'ncnn::Extractor::extract(int, ncnn::Mat&)'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:51: error: undefined reference to 'ncnn::Net::Net()'
/Users/H3c/Downloads/squeezencnn-AX/app/src/main/jni/squeezencnn_jni.cpp:51: error: undefined reference to 'ncnn::Net::~Net()'
collect2: error: ld returned 1 exit status
make: *** [/Users/H3c/Downloads/squeezencnn-AX/app/src/main/obj/local/armeabi-v7a/libsqueezencnn.so] Error 1
h3c-macbook:jni H3c$

我编译armeabi-v7a是正常的，没问题，NDK用的是android-ndk-r16b，不知道哪里出了问题。

[mrbrantofgithub]

你解决这个问题了么？我也遇到相同的错误

[mrbrantofgithub]

很奇怪的是application.mk中我设置了app_abi为arm64-v8a,这里报错的时候还是显示为armeabi-v7a

[mrbrantofgithub]

我找到我的原因了，在build.gradle中，我之前写了abiFilters 'armeabi-v7a','arm64-v8a' 然后我把'armeabi-v7a'去掉就能正确编译运行了