C++11 alternative to OpenMP with clang

OpenMP version :

// parallelfor_gcc.cpp// g++ -O2 -Wall -std=c++11 -fopenmp parallelfor_gcc.cpp#include <cmath>#include <vector>int main() {  unsigned int size = 1e8;  std::vector<double> vect(size);#pragma omp parallel for  for (unsigned int i=0; i<size; i++) {    vect[i] = sin(2*M_PI*i/(double)size);  }  return 0;}

C++11 version:

// parallelfor_clang.cpp// clang++ -O4 -Wall -std=c++11 -lpthread parallelfor_clang.cpp#include <cmath>#include <thread>#include <vector>void parallelFor(const unsigned int size,                  std::function<void(const unsigned int)> func) {  const unsigned int nbThreads = std::thread::hardware_concurrency();  std::vector < std::thread > threads;  for (unsigned int idThread = 0; idThread < nbThreads; idThread++) {    auto threadFunc = [=, &threads]() {      for (unsigned int i=idThread; i<size; i+=nbThreads) {        func(i);      }    };    threads.push_back(std::thread(threadFunc));  }  for (auto & t : threads) t.join();}int main() {  unsigned int size = 1e8;  std::vector<double> vect(size);  auto myFunc = [=, &vect](unsigned int i){    vect[i] = sin(2*M_PI*i/(double)size);  };  parallelFor(size, myFunc);  return 0;}

OpenMP clauses (firstprivate...) can be implemented in the same way but it's (a little) more work...