std：：normal_distribution<double> 导致 Windows 与 Linux 的顺序错误？

有人访问过这个问题吗?每个实现都不需要产生相同的数据。在实践中——在arm、x86、免费和商业编译器之间，STL实现有很多不同吗?

// g++ --std=c++11 -o a minimal.cpp && ./a
#include <iostream>
#include <random>
using namespace std;
int
main()
{
  std::mt19937_64 gen;
  gen.seed(17);
  cout << "nNormaln";
  normal_distribution<double> distr1;
  for (int i = 0; i < 2; i++) {
    double delay = distr1(gen);
    printf("  Value = %15.15gn", delay);
  }
  return(0);
}

/*
Results
(1) gcc-4.8.0 linux 64b version result
  Normal
    Value = 1.03167351251536
    Value = 1.21967569130525
(2) Microsoft Visual Studio Community 2015 Version 14.0.23107.0 D14REL
      or 
    Microsoft Visual Studio Professional 2012 Version 11.0.60610.01 Update 3
  Normal
    Value = 1.21967569130525
    Value = 1.03167351251536  // same values in wrong (different) order
*/

我可以理解在某些特殊的硬件平台上对生成器或分发使用不同的算法，但这种差异似乎更像是一个bug。

下面是我用来诊断差异来自哪里并解决它的一些代码:-生成器和统一分布匹配在win和linux上。-除成对顺序外，正态分布在数字上匹配

//   g++ --std=c++11 -o a workaround.cpp && ./a

#include <iostream>
#include <random>
#include <stack>

using namespace std;
typedef  std::mt19937_64  RandGenLowType;
// Helper wrapper - it did confirm that the differences
// do NOT come from the generator
class RandGenType : public RandGenLowType {
  public:
    result_type operator()() {
      result_type val = RandGenLowType::operator()();
      printf("    Gen pulled %20llun", val);
      return(val);
    }
};

typedef normal_distribution<double> NormalDistrLowType;
// Workaround wrapper to swap the output data stream pairwise
class NormalDistrType : NormalDistrLowType {
  public:
    result_type operator()(RandGenType &pGen) {
      // Keep single flow (used variables, includes) same for all platforms
      if (win64WaStack.empty()) {
        win64WaStack.push(NormalDistrLowType::operator()(pGen));
#ifdef _MSC_VER
        win64WaStack.push(NormalDistrLowType::operator()(pGen));
#endif
      }
      result_type lResult = win64WaStack.top();
      win64WaStack.pop();
      return(lResult);
    }    
  private:
    std::stack<result_type> win64WaStack;
};

int
main()
{
  RandGenType gen;
  gen.seed(17);
  // No platform issue, no workaround used
  cout << "nUniformn";
  uniform_real_distribution<double> distr;
  for (int i = 0; i < 4; i++) {
    double delay = distr(gen);
    printf("  Delay = %15.15gn", delay);
  }
  // Requires the workaround
#ifdef _MSC_VER
  cout << "Workaround code is active, swapping the output stream pairwisen";
#endif
  cout << "nNormaln";
  //normal_distribution<float> distr1;
  NormalDistrType distr1;
  for (int i = 0; i < 10; i++) {
    double delay = distr1(gen);
    printf("  Value = %15.15gn", delay);
  }
  return(0);
}