Why does it stack overflow?

I'm trying to solve Schrödinger’s equation through diagonalization. And I use C++ on VS2019 and use mkl-lapackage to get the eigenvalue and eigenvector. And the whole file is modificated from intel example of LAPACKE_dsyev. I just modificated for a small piece. But I met that:

0x00C86C79 has an unhandled exception (in schro_comp.exe): 0xC00000FD: Stack Overflow (parameter: 0x00000000, 0x00402000).

I don't know why. It's 500*500 matrix. It's not large, right? I ask someone for help.

My code is:

#include <stdlib.h>
#include <stdio.h>
#include "mkl_lapacke.h"

/* Auxiliary routines prototypes */
extern void print_matrix(char* desc, MKL_INT m, MKL_INT n, double* a, MKL_INT lda);

/* Parameters */
#define N 500//nstep
#define LDA N
#define RMIN -10.0
#define RMAX 10.0
/* Main program */
int main() {
    /* Locals */
    MKL_INT n = N, lda = LDA, info;

    /* Local arrays */
    double h = (RMAX - RMIN) / (double(N) + 1.0);
    double xi;
    double w[N];
    double a[LDA * N];
    for (int i = 0; i < N; i++) {
        xi = RMIN + double(1.0+i) * h;
        a[i*(N+1)] = 2.0 / h / h+xi * xi;
        if (i==0) {
            a[1] = -1.0 / h / h;
        }
        else if (i == N - 1) {
            a[LDA * N-2] =- 1.0 / h / h;
        }
        else {
            a[i *(N + 1)+1] = 2.0 / h / h + xi * xi;
            a[i * (N + 1) - 1] = 2.0 / h / h + xi * xi;
        }
    }
    /* Executable statements */
    printf("LAPACKE_dsyev (row-major, high-level) Example Program Results\n");
    /* Solve eigenproblem */
    info = LAPACKE_dsyev(LAPACK_ROW_MAJOR, 'V', 'U', n, a, lda, w);
    /* Check for convergence */
    if (info > 0) {
        printf("The algorithm failed to compute eigenvalues.\n");
        exit(1);
    }
    /* Print eigenvalues */
    print_matrix("Eigenvalues", 1, n, w, 1);
    /* Print eigenvectors */
    print_matrix("Eigenvectors (stored columnwise)", n, n, a, lda);
    exit(0);
} /* End of LAPACKE_dsyev Example */

/* Auxiliary routine: printing a matrix */
void print_matrix(char* desc, MKL_INT m, MKL_INT n, double* a, MKL_INT lda) {
    MKL_INT i, j;
    printf("\n %s\n", desc);
    for (i = 0; i < m; i++) {
        for (j = 0; j < n; j++) printf(" %6.2f", a[i * lda + j]);
        printf("\n");
    }
}

I have correct some errors, but it still exists....

And the matrix is like:

The matrix's last e_nstep-1 should be e_nstep-2.

Thank all people help me. The problem is solved. The space of stack on VS2019 is 1MB. So.... malloc() and free() can solve this problem.

Solution

The problem is solved. Thank all people help me. Just malloc and free solve the problem.(VS2019 stack space is 1MB by default, you can control it,too.)


#include <stdlib.h>
#include <stdio.h>
#include "mkl_lapacke.h"

/* Auxiliary routines prototypes */
extern void print_matrix(char* desc, MKL_INT m, MKL_INT n, double* a, MKL_INT lda);

/* Parameters */
#define N 500//nstep
#define LDA N
#define RMIN -10.0
#define RMAX 10.0
/* Main program */
int main() {
    /* Locals */
    MKL_INT n = N, lda = LDA, info;

    /* Local arrays */
    double h = (RMAX - RMIN) / (double(N) + 1.0);
    double xi;
    double *w;
    double *a;

    w= (double*)malloc(sizeof(double) * N);
    a = (double*)malloc(sizeof(double) * N*LDA);

    for (int i = 0; i < N; i++) {
        xi = RMIN + double(1.0+i) * h;
        a[i*(N+1)] = 2.0 / h / h+xi * xi;
        if (i==0) {
            a[1] = -1.0 / h / h;
        }
        else if (i == N - 1) {
            a[LDA * N-2] =- 1.0 / h / h;
        }
        else {
            a[i *(N + 1)+1] = 2.0 / h / h + xi * xi;
            a[i * (N + 1) - 1] = 2.0 / h / h + xi * xi;
        }
    }
    /* Executable statements */
    printf("LAPACKE_dsyev (row-major, high-level) Example Program Results\n");
    /* Solve eigenproblem */
    info = LAPACKE_dsyev(LAPACK_ROW_MAJOR, 'V', 'U', n, a, lda, w);
    /* Check for convergence */
    if (info > 0) {
        printf("The algorithm failed to compute eigenvalues.\n");
        exit(1);
    }
    /* Print eigenvalues */
    print_matrix("Eigenvalues", 1, n, w, 1);
    /* Print eigenvectors */
    print_matrix("Eigenvectors (stored columnwise)", n, n, a, lda);
    free(a);
    free(w);
    exit(0);
} /* End of LAPACKE_dsyev Example */

/* Auxiliary routine: printing a matrix */
void print_matrix(char* desc, MKL_INT m, MKL_INT n, double* a, MKL_INT lda) {
    MKL_INT i, j;
    printf("\n %s\n", desc);
    for (i = 0; i < m; i++) {
        for (j = 0; j < n; j++) printf(" %6.2f", a[i * lda + j]);
        printf("\n");
    }
}