Win CE stack push pop in c

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <windowsx.h>
#include <commctrl.h>
#include <aygshell.h>

typedef struct node tnode;
typedef struct node* nodeptr;

struct node
{   int node_id;
     nodeptr prev;
};

nodeptr talloc(void) 
{ return( (nodeptr)malloc(sizeof( struct node)) );
}

nodeptr push(nodeptr parent)
{  nodeptr newnode = talloc();
    newnode->node_id = 
                    (parent->node_id) + 1;  
    newnode->prev = parent;
    return newnode;   
}

nodeptr pop( nodeptr t )
{  
    if(t != NULL)
    { 
        nodeptr temp = t;  
        t = t->prev;
        free( temp );
        return t;   
    }
 }

void display_stack(nodeptr temp)
{
    printf("stack\n");
    while(temp != NULL) 
    {  printf("%d\n", temp->node_id );
        temp = temp->prev; 
    }
}

int APIENTRY WinMain(
    HINSTANCE hInstance,
    HINSTANCE hPrevInstance,
    LPTSTR lpCmdLine,
    int nCmdShow )
{ 
    nodeptr top; 
    nodeptr root;
    root = talloc();
    root->node_id = 1;
    root->prev = NULL;
    top = root;

    top = push(top);
    top = push(top);
    display_stack(top);

    top = pop(top);
    top = pop(top);
    display_stack(top);

    printf("\n");
    top = pop(top);      // free(root);
    system ("pause");
     return 0;
}