Android NDK 与共享的 .so 链接

Question

我有一个测试应用程序，我正在尝试与 ibicuuc 和 libicui18n 链接。 （这是大型项目的第一步）。

我将这些作为预建库包含在我的项目中

LOCAL_SHARED_LIBRARIES := libicuuc libicui18n

从 git 存储库按原样编译：

https://android.googlesource.com/platform/external/icu4c/

这是来自 clean 的构建日志：

$ ndk-build
[armeabi-v7a] Prebuilt       : libicui18n.so <= /usr/local/opt/android/libs/libs/armeabi-v7a/
[armeabi-v7a] Install        : libicui18n.so => libs/armeabi-v7a/libicui18n.so
[armeabi-v7a] Prebuilt       : libicuuc.so <= /usr/local/opt/android/libs/libs/armeabi-v7a/
[armeabi-v7a] Install        : libicuuc.so => libs/armeabi-v7a/libicuuc.so
[armeabi-v7a] Compile++ thumb: main <= main.cc
[armeabi-v7a] SharedLibrary  : libmain.so
[armeabi-v7a] Install        : libmain.so => libs/armeabi-v7a/libmain.so

这看起来不错并且作为测试如果我错过了 LOCAL_SHARED_LIBRARIES 中的库，则构建会按预期失败

/usr/local/opt/android/android-ndk-r10c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/main/main.o: in function test_icu():jni/src/main.cc:71: error: undefined reference to 'unum_countAvailable_53'
collect2: ld returned 1 exit status

一切都很好，但是当应用程序运行时，找不到符号：

D/dalvikvm( 7846): Trying to load lib /data/app-lib/net.alphawave.test.nativelibs-1/libmain.so 0x41e646a0
E/dalvikvm( 7846): dlopen("/data/app-lib/com.example.test.nativelibs-1/libmain.so") failed: dlopen failed: cannot locate symbol "unum_countAvailable_53" referenced by "libmain.so"...
W/dalvikvm( 7846): Exception Ljava/lang/UnsatisfiedLinkError; thrown while initializing Lcom/example/test/nativelibs/NativeLibs;
W/dalvikvm( 7846): Class init failed in newInstance call (Lcom/example/test/nativelibs/NativeLibs;)
D/AndroidRuntime( 7846): Shutting down VM
W/dalvikvm( 7846): threadid=1: thread exiting with uncaught exception (group=0x41591ba8)
E/AndroidRuntime( 7846): FATAL EXCEPTION: main
E/AndroidRuntime( 7846): Process: com.example.test.nativelibs, PID: 7846
E/AndroidRuntime( 7846): java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "unum_countAvailable_53" referenced by "libmain.so"...

我已经尝试过预加载这些库，但这似乎没有帮助：

static {
    System.loadLibrary("icuuc");
    System.loadLibrary("icui18n");
    System.loadLibrary("main");
}

这会导致：

D/dalvikvm( 8277): Trying to load lib /data/app-lib/com.example.test.nativelibs-1/libicuuc.so 0x41e6d310
D/dalvikvm( 8277): Added shared lib /data/app-lib/com.example.test.nativelibs-1/libicuuc.so 0x41e6d310
D/dalvikvm( 8277): No JNI_OnLoad found in /data/app-lib/com.example.test.nativelibs-1/libicuuc.so 0x41e6d310, skipping init
D/dalvikvm( 8277): Trying to load lib /data/app-lib/com.example.test.nativelibs-1/libicui18n.so 0x41e6d310
D/dalvikvm( 8277): Added shared lib /data/app-lib/com.example.test.nativelibs-1/libicui18n.so 0x41e6d310
D/dalvikvm( 8277): No JNI_OnLoad found in /data/app-lib/com.example.test.nativelibs-1/libicui18n.so 0x41e6d310, skipping init
D/dalvikvm( 8277): Trying to load lib /data/app-lib/com.example.test.nativelibs-1/libmain.so 0x41e6d310
E/dalvikvm( 8277): dlopen("/data/app-lib/com.example.test.nativelibs-1/libmain.so") failed: dlopen failed: cannot locate symbol "unum_countAvailable_53" referenced by "libmain.so"...

该符号存在于 icui18n 库中：

$ arm-linux-gnueabi-readelf -aW libicui18n.so | grep unum_countAvailable 
3700: 000ee8a9     4 FUNC    GLOBAL DEFAULT    7 unum_countAvailable_53

我错过了什么？还是 icu* 构建需要一些模组？

谢谢，

Answer 1

链接库（版本 53）和 /system 库（版本 51）不匹配，运行时链接器使用后者。

我问了一个修改后的问题！