Question

I have tried for a long time and cannot figure out where this 'core dumped' is coming from. I am using c on cygwin. Commenting out the threads gets rid of the problem but commenting out the entire code in the thread does nothing. Could this have something to do with the calling of the thread?? It appeared to be working then this suddenly happened. I have deleted most of the code and this is what is left-

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <stdint.h>
#include <pthread.h>
#include <string.h>


typedef enum {true=1, false=0} bool;

void *piThread(void *arg);
int finished;

int main(int argc, char *argv[])
{
    int i;
    int threads;
    bool display = false;
    long double pI = 0.0;
    void *status = malloc(sizeof(int));
    pthread_t thread_id[threads];

    if(argc < 2) {printf("not enough arguments"); exit(1);
    }else threads = atoi(argv[1]);

    if(argc == 3)
        if (strcmp(argv[2], "b") == 0)
            display = true;

    for(i=0; i<threads; i++)
    {
            pthread_create(&thread_id[i], NULL, piThread, NULL);    
            pthread_join(thread_id[i], &status);
            printf("pi: %Lf\n", pI);
    }
    return 0;
}

void *piThread(void *arg)
{
    int number = 0;
    number = 74;
    pthread_exit((void*)number);
}

This is causing an aborted error.

Stack trace:
Frame     Function  Args
0028A6A4  76821184  (000000D0, 0000EA60, 00000000, 0028A7D8)
0028A6B8  76821138  (000000D0, 0000EA60, 000000A4, 0028A7B4)
0028A7D8  610DBE29  (00000000, FFFFFFFE, 77403B23, 77403B4E)
0028A8C8  610D915E  (00000000, 0028A918, 00000001, 00000000)
0028A928  610D962E  (76D709CD, 7427AED9, 00000003, 00000006)
0028A9D8  610D9780  (000011E8, 00000006, 002B002B, 800483D8)
0028A9F8  610D97AC  (00000006, 0028CE80, FFFDE000, 00000000)
0028AA28  610D9A85  (000000D0, 0028ABF0, 0028AA58, 610FA223)
End of stack trace

I have no idea what is wrong!!
command line is-
gcc pi.exe 100
any combination ABOVE 26 causes this fault.
Thank you for any insight

Answer 1

You are allocating thread_id before ‘threads’ is defined. This should fix that problem at least.

if(argc < 2) {printf("not enough arguments"); exit(1);
}else threads = atoi(argv[1]);
pthread_t thread_id[threads];