Queue implimentation

hello everyone i am trying to create a code to represent a queue using a linked list but i get the disturbing "Segmentation fault coredumped" after compilation any help plese thist are the three parts of the code

Code:

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#ifndef QUEUE_H
#define QUEUE_H

#include <stdbool.h>

typedef int Item;
typedef struct queue_type *Queue;
typedef struct node *return_node;

Queue create(void);
void insert(Queue fxn, Item x);
Item remove_q(Queue fxn);
return_node return_first(Queue fxn);
return_node return_last(Queue fxn);
bool  is_empty(Queue fxn);
void terminate(char *message);

#endif

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This is the function definations

Code:

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

struct node{
    Item *p;
    struct node *next;
    };
   
struct queue_type{
    struct node *first;
    struct node *last;
    };

Queue create(void)
{
    Queue fxn = malloc (sizeof(struct queue_type));
    if(fxn==NULL){
            terminate("\nError in create: ");
            exit(EXIT_FAILURE);
        }
    fxn->first=NULL;
    fxn->last=NULL;
    return fxn;
}
       

void insert (Queue fxn, Item x)
{
    struct  node *new_node = malloc(sizeof(struct node));
    if(new_node==NULL){
        terminate("Error in insert:");
        exit(EXIT_FAILURE);
    }
   
    new_node->p = malloc(sizeof(x));
    if(new_node->==NULL){
        terminate("Error in allocating size for new node pointer");
        exit(EXIT_FAILURE);
    }
   
    new_node->p = &x;
    new_node->next = NULL;
    if(fxn->first==NULL){
        fxn->first = new_node;
    }
    else{
        struct  node *old_last;
        old_last=fxn->last;
        old_last->next=new_node;
        fxn->last=new_node;
    }
}

Item remove_q (Queue fxn)
{
    struct node *old_first;
    Item i;
    old_first=fxn->first;
    i = *(old_first->p);
    fxn->first=old_first->next;
    free(old_first);
   
    return i;
}

return_node  return_first(Queue fxn)
{
    return fxn->first;
}

return_node return_last(Queue fxn)
{
    return fxn->last;
}

bool is_empty(Queue fxn)
{
    return fxn->last == NULL;
}       

void terminate(char *message)
{
    printf("\n%s",message);
    exit(EXIT_FAILURE);
}

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This is a sample to test the code

Code:

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#include<stdio.h>
#include "queue.h"

int main(void)
{
    printf("Create succeded");
    Queue s1,s2;
    int n;
    printf("Create succeded");
    s1=create();
    s2=create();
    printf("Create succeded");
   
    insert (s1,1);
    insert (s1,2);
    insert (s1,3);
    insert (s1,4);
    insert (s2,5);
   
    int i;
    for(i=0;i<3;i++){
        printf("Popped %d from s1\n",remove_q(s1));
    }
    printf("Poooed %d from s2\n",remove_q(s2));
    if(is_empty(s1)){
        printf("s1 is empty\n");
    }
    if(is_empty(s2)){
        printf("s2 is empty\n");
    }
}

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In the same way that you extract an item using this
i = *(old_first->p);

> new_node->p = &x;
You need to do the same thing when inserting into the list, say
*(new_node->p) = x;

Quote:

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Originally Posted by Salem

In the same way that you extract an item using this
i = *(old_first->p);

> new_node->p = &x;
You need to do the same thing when inserting into the list, say
*(new_node->p) = x;

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Thanks man! that was of gr8 help i have debuged it already i just wish to ask if a queue is very applicable?