Bus Error 10 on Mac when creating a binary tree in C

Question

I am getting bus error when I'm trying to create a binary tree using structures in C. Please suggest me a solution to overcome this bus error. I am compiling on Mac OSX.

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

struct node {
    int data;
    struct node* left;
    struct node* right;
};

struct node* NewNode(int data) { 
  struct node* inode ;
  inode->data = data; 
  inode->left = NULL; 
  inode->right = NULL;
  printf("%d\n", inode->data);
  return(inode); 
}

struct node* insert(struct node* node ,int data){ 
    if(node == NULL)
        return(NewNode(data)); 
    else{
        if(data <= node->data)
            node->left = insert(node->left, data);
        else
            node->right = insert(node->right, data);
        return(node);
    }

}

struct node* build123a() { 
  struct node* root = newNode(2); 

  struct node* lChild = newNode(1); 
  struct node* rChild = newNode(3);
  root->left = lChild; 
  root->right= rChild;

  return(root); 
}

int main(void) {

    build123a();    

}

ouput : Bus Error 10

Answer 1

In your newNode function you are defining the structure pointer struct node* inode but not allocating it. And then accessing it to store data, which is incorrect.

inode will have random value (which is taken as address) and when accessing that address, you may get bus error.

You need to allocate memory in your function, like

  struct node* NewNode(int data) { 
      struct node* inode ;
      inode = malloc(sizeof(*inode)); //allocate memory
      inode->data = data; 
      inode->left = NULL; 
      inode->right = NULL;
      printf("%d\n", inode->data);
      return(inode); 
  }