undefined reference to ....tbb compilation error

[luca_d_]

THIS IS THE CODE (i use clion.... and cmake)

#include "tbb/parallel_for.h"
#include "tbb/task_scheduler_init.h"
#include <iostream>
#include <vector>

struct mytask {
    mytask(size_t n)
            :_n(n)
    {}
    void operator()() {
        for (int i=0;i<1000000;++i) {}  // Deliberately run slow
        std::cerr << "[" << _n << "]";
    }
    size_t _n;
};

int main(int,char**) {

    //tbb::task_scheduler_init init;  // Automatic number of threads
    tbb::task_scheduler_init init(tbb::task_scheduler_init::default_num_threads());  // Explicit number of threads

    std::vector<mytask> tasks;
    for (int i=0;i<1000;++i)
        tasks.push_back(mytask(i));

    tbb::parallel_for(
            tbb::blocked_range<size_t>(0,tasks.size()),
            [&tasks](const tbb::blocked_range<size_t>& r) {
                for (size_t i=r.begin();i<r.end();++i) tasks();
            }
    );

    std::cerr << std::endl;

    return 0;
}

the error is :

CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "main":
/home/luca/CLionProjects/fibonacci_parallelo/main.cpp:20: riferimento non definito a "tbb::task_scheduler_init::default_num_threads()"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "tbb::interface9::internal::start_for<tbb::blocked_range<unsigned long>, main::{lambda(tbb::blocked_range<unsigned long> const&)#1}, tbb::auto_partitioner const>::run(tbb::blocked_range<unsigned long> const&, {lambda(tbb::blocked_range<unsigned long> const&)#1} const&, tbb::auto_partitioner&)":
/home/luca/tbb-2017_U7/include/tbb/parallel_for.h:87: riferimento non definito a "tbb::task_group_context::~task_group_context()"
/home/luca/tbb-2017_U7/include/tbb/parallel_for.h:87: riferimento non definito a "tbb::task_group_context::~task_group_context()"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o:(.rodata+0xf8): riferimento non definito a "typeinfo for tbb::task"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "tbb::task_group_context::task_group_context(tbb::task_group_context::kind_type, unsigned long)":
/home/luca/tbb-2017_U7/include/tbb/task.h:463: riferimento non definito a "tbb::task_group_context::init()"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "tbb::task::task()":
/home/luca/tbb-2017_U7/include/tbb/task.h:569: riferimento non definito a "vtable for tbb::task"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "tbb::task::~task()":
/home/luca/tbb-2017_U7/include/tbb/task.h:573: riferimento non definito a "vtable for tbb::task"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "tbb::task::is_cancelled() const":
/home/luca/tbb-2017_U7/include/tbb/task.h:875: riferimento non definito a "tbb::task_group_context::is_group_execution_cancelled() const"
CMakeFiles/fibonacci_parallelo.dir/main.cpp.o: nella funzione "operator new(unsigned long, tbb::internal::allocate_root_with_context_proxy const&)":
/home/luca/tbb-2017_U7/include/tbb/task.h:1018: riferimento non definito a "tbb::internal::allocate_root_with_context_proxy::allocate(unsigned long) const"

*and other more*

for every function in tbb::task there is "a unspecified reference to...."

[Alexei_K_Intel]

Hi,

Do you link Intel TBB library to the application? E.g. "-ltbb" with gcc and some other compilers.

Regards,
Alex