struct hashmap {
    int key;
    int val;
};

int hash_find(int num, int size, struct hashmap* hash) {
    int k, i;
    for(i = 0; i < size; i++) {
        k = (num + i) % size;
        if(hash[k].key == num) return hash[k].val;
    }
    return -1;
}

void hash_add(int num, int size, int index, struct hashmap* hash) {
    int k, i;
    for(i = 0; i < size; i++) {
        k = (num + i) % size;
        if(hash[k].key == -9999 && hash[k].val == -9999) {
            hash[k].key = num;
            hash[k].val = index;
            return;
        }
    }
}

int* twoSum(int* nums, int numsSize, int target, int* returnSize) {       
    int* res = calloc((*returnSize = 2), sizeof(int));
    struct hashmap* hash = calloc(numsSize, sizeof(struct hashmap));
    int i;

    for(i = 0; i < numsSize; i++) {
        hash[i].key = -9999;
        hash[i].val = -9999;
    }

    for(i = 0; i < numsSize; ++i) {
        int k = target - nums[i];
        int result = hash_find(k, numsSize, hash);

        if(result >= 0) {
            res[0] = result;
            res[1] = i;
            break;
        } else {
            hash_add(nums[i], numsSize, i, hash);
        }
    }

    free(hash); // Free allocated memory for hash

    return res;
}

it gives address sanitizer error and highlights this line if(hash[k].key == num) return hash[k].val; when run on leetcode with testcase [0,4,3,0] with target 0.

** i have created hash table with linear probing**

it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.
it gives address sanitizer error when run on leetcode with testcase [0,4,3,0] with target 0.