c - Iteration through linked list leads to Segmentation fault -


i wrote simple linked list, when iterating through list via add() , display() program seg faults. 

#include <stdlib.h> #include <stdio.h>  typedef struct entry {     void *value;     struct entry *next; } entry;  typedef struct list {     entry *items; } list;  list *create(void) {     list *l;      l = malloc (sizeof(list));     l->items = malloc(sizeof(entry*));     l->items->next = null;      return l; }  void add(list *l, void *value) {     entry *temp, *last, *new;      (temp = l->items; temp != null; temp = temp->next) {         last = temp;     }      new = malloc(sizeof(*new));      new->value = value;     new->next = null;      last->next = new; }  void display(list *l) {     entry *temp;      (temp = l->items; temp != null; temp = temp->next) {         printf("%s\n", temp->value);     } }  int main(void) {     list *l = create();      add(l, "item1");     add(l, "item2");     add(l, "item3");     add(l, "item4");      display(l);      return 0; }

i have tested code on few machines , works on few , doesn't on others. i'm clueless source of error.

in addition wrong size passed malloc fatalerror mentioned, allocate memory l->items

list *create(void) {     list *l;      l = malloc (sizeof(list));     l->items = malloc(sizeof(entry*));     l->items->next = null;      return l; }

but don't ever set l->items->value anything, it's uninitialised pointer , when try dereference when printing

void display(list *l) {     entry *temp;      (temp = l->items; temp != null; temp = temp->next) {         printf("%s\n", temp->value);     } }

in first iteration of loop, can lead segfault if insufficient allocation size didn't cause 1 before.


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