can't create dynamic relocation R_AARCH64_ADD_ABS_LO12_NC against symbol

Question

OS: Ubuntu 20.04

MlPack(branch): master

I am trying to build a program which is dependent on mlpack for android. For that I am using ndk-build. To make the library compatible for arm64 architecture, I have used buildroot environment 2020.08.1 to create the sysroot and aarch64-linux-gnu-gcc and aarch64-linux-gnu-g++. I have followed this link and set the following menuconfig to do that:

    Target options → TargetArchitecture = AArch64 (Little Endian)
    Toolchain → Toolchain type = External
    Toolchain  → Toolchain = Linaro AArch64
    Filesystem images → enable "tar the root file system"

Then, in mlpack/build folder I have run the following command:

cmake -DDEBUG=OFF -DPROFILE=OFF -DBUILD_MARKDOWN_BINDINGS=OFF -DBUILD_PYTHON_BINDINGS=OFF -DBUILD_GO_BINDINGS=OFF -DBUILD_JULIA_BINDINGS=OFF -DBUILD_R_BINDINGS=OFF -DCMAKE_TOOLCHAIN_FILE=../board/crosscompile-toolchain.cmake -DBOARD_NAME="RPI4" -DDISABLE_DOWNLOADS=OFF -DTOOLCHAIN_PREFIX=//home/niaz/buildroot-2020.08.1/output/host/bin/aarch64-linux-gnu- -DCMAKE_SYSROOT=/home/niaz/buildroot-2020.08.1/output/host/arm64-buildroot-linux-gnu/sysroot ../

I followed this command here for that.

But after I try to compile the following code to ndk-build, I get the error: hello.hpp

#include <string.h>
#include <iostream>
#include <fstream>

using namespace std;

class hello{
    public:
    string getJniString(string save_model_path);
};

hello.cpp

#include "hello.hpp"
#include "mlpack/core.hpp"
#include "mlpack/methods/random_forest/random_forest.hpp"
#include "mlpack/methods/decision_tree/random_dimension_select.hpp"
#include "mlpack/core/cv/k_fold_cv.hpp"
#include "mlpack/core/cv/metrics/accuracy.hpp"
#include "mlpack/core/cv/metrics/precision.hpp" 
#include "mlpack/core/cv/metrics/recall.hpp"

 
using namespace arma;
using namespace mlpack;
using namespace mlpack::tree;
using namespace mlpack::cv;
using namespace std;

string hello::getJniString(string save_model_path){
    string val = "";
    mat dataset;
    bool loaded = mlpack::data::Load("encoded_food.txt",dataset);
    if (!loaded){
        val = "failed to load";
        return val;
    }
        

    Row<size_t> labels;
    labels = conv_to<Row<size_t>>::from(dataset.row(dataset.n_rows - 1));
    dataset.shed_row(dataset.n_rows - 1);
    const size_t numClasses = 4;
    const size_t minimumLeafSize = 5;
    const size_t numTrees = 10;
    RandomForest<GiniGain, RandomDimensionSelect> rf;
    rf = RandomForest<GiniGain, RandomDimensionSelect>(dataset, labels,
        numClasses, numTrees, minimumLeafSize);

    Row<size_t> predictions;
    rf.Classify(dataset, predictions);
    const size_t correct = arma::accu(predictions == labels);
    val = "Training Accuracy: " + to_string(double(correct) / double(labels.n_elem));
    mlpack::data::Save(save_model_path, "model", rf, false);
    return val;

}

Android.mk

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_CFLAGS += -I$(LOCAL_PATH)/boost
LOCAL_LDLIBS += -L$(LOCAL_PATH)/lib/ -lboost_serialization-clang-mt-a64-1_74 -lboost_program_options-clang-mt-a64-1_74 -lmlpack
LOCAL_LDFLAGS += -Wl

LOCAL_CPPFLAGS += -frtti
LOCAL_CPPFLAGS += -fexceptions
LOCAL_CPPFLAGS += -fopenmp
LOCAL_CPPFLAGS += -fPIC

LOCAL_CFLAGS += -B/usr/lib/x86_64-linux-gnu
LOCAL_CPP_FEATURES += exceptions 

LOCAL_MODULE = hello-jni-prebuilt
CODE_PATH := .
LOCAL_C_INCLUDES := $(LOCAL_PATH)/libs/build/include $(LOCAL_PATH)
LOCAL_SRC_FILES = hello.cpp
include $(BUILD_SHARED_LIBRARY)

Application.mk

APP_PLATFORM := android-21
APP_CFLAGS += -Wno-error=format-security
APP_ABI := all
NDK_TOOLCHAIN_VERSION := clang++
APP_STL:= c++_static
APP_ALLOW_MISSING_DEPS=true

Error

ld: error: relocation R_AARCH64_ADR_PREL_PG_HI21 cannot be used against symbol std::runtime_error::~runtime_error(); recompile with -fPIC
>>> defined in /home/niaz/NDK/android-ndk-r23b-linux/android-ndk-r23b/sources/cxx-stl/llvm-libc++abi/../llvm-libc++/libs/arm64-v8a/libc++abi.a(stdlib_stdexcept.o)
>>> referenced by prefixedoutstream.cpp
>>>               prefixedoutstream.cpp.o:(_ZN6mlpack4util17PrefixedOutStream9BaseLogicIbEENSt9enable_ifIXntsrN4arma12is_arma_typeIT_EE5valueEvE4typeERKS6_) in archive /home/niaz/u/new/android-deliverables-24.2/jni/lib/libmlpack.a

I have found in some similar questions that adding -fPIC -WL -z as flags should solve this issue. But I do not understand how to add them in Android.mk or Application.mk

Answer 1

Even if I add -fPIC to CFlags the error still occurs. I solve same issue by send -Bsymbolic to ld, see more at https://github.com/google/ExoPlayer/issues/9933#issuecomment-1029775358