This code keeps giving me a segmentation fault why?

Applications Programming
1 
#include<stdlib.h>
#include <pthread.h> 
#include "tlpi_hdr.h"
#include <stdio.h> 
static volatile int glob = 0;

static struct { 
pthread_t t1,t2; 
} *thread; 


static void *     /* Loop 'arg' times incrementing 'glob' */ 
threadFunc(void *arg) 
{ 

int loops = *((int *) arg); 
int loc, j, s;
 
if (s != 0)
errExitEN(s, "pthread_mutex_lock");
for (j = 0; j < loops; j++) { 
loc = glob; 
printf("The ID of this thread is: %u\n", (unsigned int)pthread_self());
printf("glob = %d\n", glob);
sleep(2);
loc++; 
glob = loc; 
if (s != 0)
errExitEN(s, "pthread_mutex_unlock");


} 
return NULL; 
} 


int 
main(int argc, char *argv[]) 
{ 
int loops=0;
int s; 

loops = (argc > 1) ? getInt(argv[1], GN_GT_0, "num-loops") : 10000000; 
s = pthread_create(&thread[loops].t1, NULL, threadFunc, &loops);
if (s != 0) 
errExitEN(s, "pthread_create"); 
s = pthread_create(&thread[loops].t2, NULL, threadFunc, &loops);
if (s != 0) 
errExitEN(s, "pthread_create"); 
s = pthread_join(thread[loops].t1, NULL); 
if (s != 0) 
errExitEN(s, "pthread_join"); 
s = pthread_join(thread[loops].t2, NULL); 
if (s != 0) 
errExitEN(s, "pthread_join"); 
printf("final glob = %d\n", glob); 
exit(EXIT_SUCCESS); 
}
2

You don't allocate any memory for your "thread" variable to point to.

So "thread[loops]" point to some random location.

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