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/*
Ubuntu 20.04.1 LTS (Focal Fossa)
gcc (Ubuntu 9.3.0-10ubuntu2) 9.3.0
 
gcc -std=c99 -Wall -Wextra -Wpedantic -Wshadow -O0 -DDEBUG -g main.c
 
Program received signal SIGSEGV, Segmentation fault.
0x0000555555555180 in main () at main.c:31
31  {
 
 
gcc -std=c99 -Wall -Wextra -Wpedantic -Wshadow -O1 -DNDEBUG -g main.c OK
gcc -std=c99 -Wall -Wextra -Wpedantic -Wshadow -O2 -DNDEBUG -g main.c OK
gcc -std=c99 -Wall -Wextra -Wpedantic -Wshadow -O3 -DNDEBUG -g main.c OK
 
edit:
possible stack overflow
 
solution:
use malloc
 
https://pastebin.com/fYRAbMtb
or https://pastebin.com/EuPakt7a
 
Tnx to ##C on Freenode !
*/
 
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
 
#define TEST_A_MAX_SIZE 1000000 
 
struct thread_test_a
{
    uint32_t variables[TEST_A_MAX_SIZE];
    uint32_t test_count;
};
 
int main()
{ // line 31
 
    struct thread_test_a thread_test_1;
    struct thread_test_a thread_test_2;
    struct thread_test_a thread_test_3;
 
    thread_test_1.test_count = TEST_A_MAX_SIZE;
    thread_test_2.test_count = 10;
    thread_test_3.test_count = 50;
 
    thread_test_1.variables[TEST_A_MAX_SIZE-1] = 1;
    thread_test_2.variables[10] = 2;
    thread_test_3.variables[50] = 3;
 
    printf( "%d\n", thread_test_1.variables[TEST_A_MAX_SIZE-1] );
    printf( "%d\n", thread_test_2.variables[10] );
    printf( "%d\n", thread_test_3.variables[50] );
 
    return 0;
}