Android NDK CMakeLists.txt: ошибка: неопределенная ссылка на:

Question

Я огляделся, но мне удалось найти решения, которые используют Android.mk и Application.mk. Правильно ли я полагаю, что с помощью CMakeLists.txt мне не нужны ни эти файлы? Это мое первое предприятие в использовании Android NDK.

Я основал свой CMakeLists.txt от SuperpoweredExample, и я позвонил в свою библиотеку nativelib. Кажется, что .cpp-файл не может найти ссылки в файле заголовка. Я делаю что-то неправильно? Он строит отлично, но он просто бросает эти ошибки при компиляции.

CMakeLists.txt:

cmake_minimum_required(VERSION 3.4.1) 

# Creates and names a library, sets it as either STATIC 
# or SHARED, and provides the relative paths to its source code. 
# You can define multiple libraries, and CMake builds it for you. 
# Gradle automatically packages shared libraries with your APK. 

add_library(# Sets the name of the library. 
      nativelib 

      # Sets the library as a shared library. 
      SHARED 

      # Provides a relative path to your source file(s). 
      # Associated headers in the same location as their source 
      # file are automatically included. 
      G:/Git/NDKTest/app/src/main/jni/nativelib.cpp) 

# Searches for a specified prebuilt library and stores the path as a 
# variable. Because system libraries are included in the search path by 
# default, you only need to specify the name of the public NDK library 
# you want to add. CMake verifies that the library exists before 
# completing its build. 

find_library(# Sets the name of the path variable. 
       log-lib 

       # Specifies the name of the NDK library that 
       # you want CMake to locate. 
       log) 

# Specifies libraries CMake should link to your target library. You 
# can link multiple libraries, such as libraries you define in the 
# build script, prebuilt third-party libraries, or system libraries. 

target_link_libraries(# Specifies the target library. 
         nativelib 

         # Links the target library to the log library 
         # included in the NDK. 
         ${log-lib}) 

//////////////////////////////////////////////////////////////  
////////////////////////////////////////////////////////////// 
// Below here is copy and pasted from the SuperpoweredExample 
////////////////////////////////////////////////////////////// 
////////////////////////////////////////////////////////////// 

set(
    PATH_TO_SUPERPOWERED 
    "C:/Users/j/Downloads/Superpowered/Superpowered" 
) 

message(${ANDROID_ABI}) 

file(GLOB CPP_FILES "*.cpp") 

add_library(
    SuperpoweredExample 
    SHARED 
    ${CPP_FILES} 
    ${PATH_TO_SUPERPOWERED}/AndroidIO/SuperpoweredAndroidAudioIO.cpp 
) 

include_directories(src/main/jni) 
include_directories(${PATH_TO_SUPERPOWERED}) 

target_link_libraries(
    SuperpoweredExample 
    log 
    android 
    OpenSLES 
    ${PATH_TO_SUPERPOWERED}/libSuperpoweredAndroid${ANDROID_ABI}.a 
    nativelib 
) 

StackTrace:

Error:FAILURE: Build failed with an exception. 

* What went wrong: 
Execution failed for task ':app:externalNativeBuildDebug'. 
> Build command failed. 
Error while executing 'G:\sdk1\cmake\3.6.3155560\bin\cmake.exe' with arguments {--build G:\Git\NDKTest\app\.externalNativeBuild\cmake\debug\x86 --target nativelib} 
[1/2] Building CXX object CMakeFiles/nativelib.dir/nativelib.cpp.o 
[2/2] Linking CXX shared library G:\Git\NDKTest\app\build\intermediates\cmake\debug\obj\x86\libnativelib.so 
FAILED: cmd.exe /C "cd . && G:\sdk1\ndk-bundle\toolchains\llvm\prebuilt\windows-x86_64\bin\clang++.exe -target i686-none-linux-android -gcc-toolchain G:/sdk1/ndk-bundle/toolchains/x86-4.9/prebuilt/windows-x86_64 --sysroot=G:/sdk1/ndk-bundle/platforms/android-16/arch-x86 -fPIC -g -DANDROID -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -Wa,--noexecstack -Wformat -Werror=format-security -fno-exceptions -fno-rtti -g -DANDROID -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -Wa,--noexecstack -Wformat -Werror=format-security -fno-exceptions -fno-rtti -fsigned-char -Inull -O0 -fno-limit-debug-info -O0 -fno-limit-debug-info -Wl,--build-id -Wl,--warn-shared-textrel -Wl,--fatal-warnings -Wl,--no-undefined -Wl,-z,noexecstack -Qunused-arguments -Wl,-z,relro -Wl,-z,now -Wl,--build-id -Wl,--warn-shared-textrel -Wl,--fatal-warnings -Wl,--no-undefined -Wl,-z,noexecstack -Qunused-arguments -Wl,-z,relro -Wl,-z,now -shared -Wl,-soname,libnativelib.so -o G:\Git\NDKTest\app\build\intermediates\cmake\debug\obj\x86\libnativelib.so CMakeFiles/nativelib.dir/nativelib.cpp.o -llog -lm "G:/sdk1/ndk-bundle/sources/cxx-stl/gnu-libstdc++/4.9/libs/x86/libgnustl_static.a" && cd ." 
G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:16: error: undefined reference to 'SuperpoweredRoll::SuperpoweredRoll(unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:17: error: undefined reference to 'SuperpoweredFilter::SuperpoweredFilter(SuperpoweredFilterType, unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:18: error: undefined reference to 'SuperpoweredFlanger::SuperpoweredFlanger(unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:19: error: undefined reference to 'SuperpoweredRecorder::SuperpoweredRecorder(char const*, unsigned int, unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:21: error: undefined reference to 'SuperpoweredAndroidAudioIO::SuperpoweredAndroidAudioIO(int, int, bool, bool, bool (*)(void*, short*, int, int), void*, int, int, int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:28: error: undefined reference to 'SuperpoweredRecorder::stop()' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:30: error: undefined reference to 'SuperpoweredRecorder::start(char const*)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:37: error: undefined reference to 'SuperpoweredRecorder::process(float*, float*, unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:38: error: undefined reference to 'SuperpoweredFloatToShortInt(float*, short*, unsigned int, unsigned int)' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:43: error: undefined reference to 'SuperpoweredAndroidAudioIO::~SuperpoweredAndroidAudioIO()' 
    G:\Git\NDKTest\app\src\main\jni/nativelib.cpp:44: error: undefined reference to 'SuperpoweredRecorder::~SuperpoweredRecorder()' 
    clang++.exe: error: linker command failed with exit code 1 (use -v to see invocation) 
    ninja: build stopped: subcommand failed. 


* Try: 
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. 

Измененное название от nativelib к nativelib, ту же ошибку.

У меня такое чувство, что ошибка вокруг target_link_libraries() от CMakeLists.txt. Я пытаюсь связать код NativeLib с существующим кодом SuperpoweredExample.

Answer 1

Я думаю, что связывание вашего «nativelib» происходит до связывания примера Superpowered, поэтому ваш компоновщик не может найти сверхмощные части, используемые «nativelib».