MaceEngineConfig destructor problem

[serviceberry3]

Hi,

Thanks so much for this tutorial! I'm currently trying to build my Android project after creating my native code library (I named mine mace_engine.cpp instead of your native-lib.cpp) and configuring CMake. Everything seems to build, but I'm getting
../../../../src/main/cpp/mace_engine.cpp:111: error: undefined reference to 'mace::MaceEngineConfig::~MaceEngineConfig()' (111 is where the loadModel() function ends) when I try to run a build in Android Studio. It seems to find an issue destructing the instance of MaceEngineConfig that we create. I noticed that this destructor was set to default in libmace/mace.cc. Any ideas?

Thanks a lot.

[Hramchenko]

Hello, thank you for your feedback.
It seems that compiler didn't link a mace libraries with the native code. Please, send me the linker output from Studio compiler window.

[serviceberry3]

Android Studio shortens the compiler output to just this:

../../../../src/main/cpp/mace_engine.cpp:111: error: undefined reference to 'mace::MaceEngineConfig::~MaceEngineConfig()'

Do you know how I can view the full output? Also, does this CMakeLists.txt look right to you?

set(LIBMACE_DIR ${CMAKE_SOURCE_DIR}/libmace/)


include_directories(/home/nodog/VENV/opt/include/)
add_library(libmace SHARED IMPORTED)
add_library(mace_engine SHARED src/main/cpp/mace_engine.cpp)


set_target_properties(libmace PROPERTIES IMPORTED_LOCATION ${LIBMACE_DIR}/arm64-v8a/libmace.so) #${CMAKE_ANDROID_ARCH_ABI}


# Searches for a specified prebuilt library and stores the path as a
# variable. Because CMake includes system libraries 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 this
# build script, prebuilt third-party libraries, or system libraries.
target_link_libraries( # Specifies the target library.
        mace_engine
        libmace
        -ljnigraphics

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

I basically copied your CMakeLists.txt, but my native cpp file is called mace_engine, not native-lib. Inside of LIBMACE_DIR I have an arm64_v8a folder, and inside that I have libmace.a and libmace.so.

[Hramchenko]

Your CMakeLists.txt looks good :) The only reason I can think of why everything doesn't work is because of problems with the libmace.so itself. Do I understand correctly that this is the binary that you got yourself after the build?

[serviceberry3]

@Hramchenko Yes, that's correct. Could you give me more detailed steps of how you built mace? I'm worried I'm doing something wrong. I'm on Ubuntu 20.04.

[Hramchenko]

OK. Give me 2 days to try to make the project again, with the latest versions of libmace and Android Studio(maybe they changed something) :)

[Hramchenko]

Hi. Thank you for your report. I rebuilt project with latest libraries on my machine. It seems the binary version of libmace doesn't correspond with library sources.
Please download latest sources and binaries from https://github.com/XiaoMi/mace/releases/tag/v1.0.0.
If you are using latest Android Studio don't add sourceSets section. No further changes are required. I added the updated instructions to my article https://v-hramchenko.medium.com/run-your-pytorch-model-on-android-gpu-using-libmace-7e43f623d95c.
Thank you very much.

[vyi]

Hi @Hramchenko, Thank you for your efforts. This is a very neat Android Project.

I wish to clarify a doubt. You mentioned the following :

I rebuilt project with latest libraries on my machine. It seems the binary version of libmace doesn't correspond with library sources.

In the repo, I see the shared library files libmace.so is the old version (last modified 6 month back). However the CMakeLists.txt was recently modified to include header definition from v1.0.0.

Does this imply that the present library files (${LIBMACE_DIR}/${CMAKE_ANDROID_ARCH_ABI}/libmace.so) were compiled from source of these same headers (v1.0.0)?

[Hramchenko]

Hi @vyi! Thank you for your feedback. This is really wrong. I just forgot to replace the libraries :) I don't compile them at all. I simply download it from the official repository (from releases page). Thank you very much. I will now update the libraries in the project.