Android NDK - 包括预建的静态库会导致未定义的引用错误

Question

我正在尝试使用预构建的静态库构建共享库。出于某种原因，构建总是失败并给出undefined reference 错误。如果我添加LOCAL_ALLOW_UNDEFINED_SYMBOLS := true，则构建成功，但共享库只有几千字节，而静态库约为 3 兆字节......所以链接静态库似乎出了点问题。我不知道它可能是什么。我只使用 C++ 代码。

Android.mk：

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE    := kes
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
LOCAL_SRC_FILES := libkes.a

include $(PREBUILT_STATIC_LIBRARY)

include $(CLEAR_VARS)

LOCAL_MODULE    := PortaKES
LOCAL_SRC_FILES := PortaKES.cpp
LOCAL_STATIC_LIBARIES := kes

include $(BUILD_SHARED_LIBRARY)

Application.mk：

APP_ABI := all
APP_STL := stlport_static

JNI目录结构：

输出：

./obj/local/arm64-v8a/objs/PortaKES/PortaKES.o: In function `Java_com_kurzweil_portakes_KESFile_createPOLEFile':
C:\Users\niels.mylle\Documents\Kurzweil Mobile Android\PortaKES/jni/PortaKES.cpp:18: undefined reference to `CPoleFile::CPoleFile(char const*, bool, bool, CEncrypter*)'
./obj/local/arm64-v8a/objs/PortaKES/PortaKES.o: In function `Java_com_kurzweil_portakes_KESFile_createKSection':
C:\Users\niels.mylle\Documents\Kurzweil Mobile Android\PortaKES/jni/PortaKES.cpp:33: undefined reference to `CKSection::CKSection(char const*, CPoleFile*, CPoleLeaf*)'
./obj/local/arm64-v8a/objs/PortaKES/PortaKES.o: In function `Java_com_kurzweil_portakes_POLEFile_destroy':
C:\Users\niels.mylle\Documents\Kurzweil Mobile Android\PortaKES/jni/PortaKES.cpp:48: undefined reference to `CPoleFile::~CPoleFile()'
./obj/local/arm64-v8a/objs/PortaKES/PortaKES.o: In function `Java_com_kurzweil_portakes_POLEFile_exists':
C:\Users\niels.mylle\Documents\Kurzweil Mobile Android\PortaKES/jni/PortaKES.cpp:100: undefined reference to `CPoleFile::exists(char const*)'
collect2.exe: error: ld returned 1 exit status
make.exe: *** [obj/local/arm64-v8a/libPortaKES.so] Error 1

Answer 1

也许这只是问题的一部分，但至少这个引用是错误的：

LOCAL_SRC_FILES := libkes.a

您正在为所有与 ndk 兼容的架构进行构建，但始终为每个架构引用相同的静态预构建，这是行不通的。

您应该为每个目标架构使用不同的 .a，即 ./armeabi/libkes.a、./x86/libkes.a、./armeabi-v7a/libkes.a 等。在这种情况下，您可以使用 TARGET_ARCH_ABI 引用您的 .a变量，像这样：

LOCAL_SRC_FILES := $(TARGET_ARCH_ABI)/libkes.a