Hi, 

My project use a simple main using dlopen to "run" the real main function in target shared library. I use both Boost Log and ASIO (for threadpool) in the project. In Linux I found the ASIO got weird behavior with some un-initialized variables and crashing all the time. I am able to trim down my problem into a small program as below: 

// *** threadpool.cpp ***

#include <iostream> 

#include <memory> 

#include <boost/asio/io_service.hpp> 

#include <boost/bind.hpp> 

#include <boost/thread/thread.hpp> 

void print() { 

    std::cout << "print" << std::endl; 

} 

struct ThreadPool 

{ 

    void start() 

    { 

        boost::asio::io_service ioService; 

        boost::thread_group threadpool; 

        std::unique_ptr<boost::asio::io_service::work> work = std::make_unique<boost::asio::io_service::work>(ioService); 

        threadpool.create_thread(boost::bind(&boost::asio::io_service::run, &ioService)); 

        for (int i=0; i<100; ++i) 

        { 

            ioService.post(&print); 

        } 

        std::cout << "Post all calculation tasks" << std::endl; 

        work.reset(); 

        threadpool.join_all(); 

        ioService.stop(); 

        std::cout  << "Finished all calculation tasks" << std::endl; 

    } 

}; 

extern "C" void createthreadpool() 

{ 

    ThreadPool pool; 

    pool.start(); 

} 

// *** threadpool.cpp *** 

g++ -O0 -std=gnu++1y -fPIC -c -g -DLinux -DGNU_GCC -I${BOOST_HOME}/include threadpool.cpp 

g++ -shared -o libthreadpool.so threadpool.o -L${BOOST_HOME}/lib -lboost_system -lboost_date_time -lboost_thread -lboost_filesystem -lboost_regex -lboost_chrono -ldl -lstdc++ 

// *** main.cpp ***

#include <dlfcn.h> 

#include <iostream> 

int main(int argc, char** argv) { 

    typedef void* createProcess(); 

    auto service = dlopen("libthreadpool.so", RTLD_LAZY); 

    createProcess* make = reinterpret_cast<createProcess*>(dlsym(service, "createthreadpool")); 

    std::cout << "dlsym" << std::endl; 

    make(); 

    return 0; 

} 

// *** main.cpp ***

g++ -O0 -std=gnu++1y -fPIC -c -g -DLinux -DGNU_GCC main.cpp 

// Link against boost_log to simulate my problem (although it is not using any boost_log). This version will crash 

g++ -o main.bad main.o -L${BOOST_HOME}/lib -lboost_system -lboost_date_time -lboost_thread -lboost_filesystem -lboost_regex -lboost_chrono -lboost_log -ldl -lstdc++ 

// it works fine If link against libthreadpool, surprising me 

g++ -o main main.o -L/home/sysmmbuild/dev/boost -lthreadpool -L${BOOST_HOME}/lib -lboost_system -lboost_date_time -lboost_thread -lboost_filesystem -lboost_regex -lboost_chrono -lboost_log -ldl -lstdc++ 

One more finding is, if compile boost_log without thread support, the main.bad also working fine. 

I have attached the code and make.sh as make script. 

Software version 

Redhat enterprise 6.5 

g++ 4.9.1 

Boost 1.56.0 

Rgds,

Ray