我使用setrlimit调整了堆栈大小后,在堆栈上分配了一个大数组。当此数组在main()中声明,然后作为参数传递给方法时,出现分段错误。当将数组声明为方法内的局部变量时,代码将运行而不会出现任何段错误。我正在具有8GB RAM的Amdx86-64 linux机器上运行代码。
#include <iostream>
#include <sys/resource.h>
using usll = unsigned long long;
void sumArray0();
double sumArray1(double c[], usll dim);
int main(int argc, char* argv[])
{
const rlim_t stackSize = 3 * 1024UL * 1024UL * 1024UL;
struct rlimit rl;
int result;
printf("The required value of stackSize is %lu\n", stackSize);
result = getrlimit(RLIMIT_STACK, &rl);
if (result == 0)
{
if (rl.rlim_cur < stackSize)
{
rl.rlim_cur = stackSize;
result = setrlimit(RLIMIT_STACK, &rl);
if (result != 0)
{
fprintf(stderr, "setrlimit returned result = %d\n", result);
}
else
{
printf("The new value of stackSize is %lu\n", rl.rlim_cur);
}
}
}
// // This seg faults
// const usll DIM = 20000UL * 18750UL;
// double c[DIM];
// for (usll i{}; i<DIM; ++i)
// {
// c[i] = 5.0e-6;
// }
// double total = sumArray1(c, DIM); // Seg fault occurs here
sumArray0(); // This works
std::cout << "Press enter to continue";
std::cin.get();
return 0;
}
void sumArray0()
{
double total{};
const usll DIM = 20000UL * 18750UL;
double c[DIM];
for (usll i{}; i<DIM; ++i)
{
c[i] = 5.0e-6;
}
for (usll i{}; i<DIM; ++i)
{
total += c[i];
}
std::cout << "Sum of the elements of the vector is " << total << std::endl;
}
double sumArray1(double c[], usll dim)
{
double total{};
for (usll i{}; i<dim; ++i)
{
total += c[i];
}
return total;
}
我的问题是:为什么在第一种情况下会出现stackoverflow?是否是因为在对方法sumArray1()的调用中请求了新的内存块?作为参数传递给方法时,不是通过指针访问数组吗?
按照这里的建议Giant arrays causing stack overflows,我总是使用std :: vector,并且从不在堆栈上分配大数组以防止出现上述问题。如果有人知道可以使对sumArray1()的调用起作用的任何调整,技巧或变通办法,我将非常感激。
我使用setrlimit调整了堆栈大小后,在堆栈上分配了一个大数组。当此数组在main()中声明,然后作为参数传递给方法时,出现分段错误。当...