Thread: program executes but crashes when returning 0

for some reason, my code does create a random linked dynamic data structure, but whenever i try and terminate it it constatntly crashes....please help.

Code:

#include <stdlib.h>
#include <stdio.h>
#include <time.h>
int sentinel = 0;

typedef struct list{
char c;
struct list *listPtr;
} List;

void populate (List);

int main(){
srand(time(NULL));

List list1;
populate(list1);
printf("%d\n", sizeof(List)); 
free(&list1);
system("PAUSE");
return 0;
}


void populate(List list){
List *currentPtr = &list; 

for (sentinel = 0; sentinel <= 10; sentinel++){
List *newNode = (List *) malloc(sizeof(List));
currentPtr->listPtr = newNode;
newNode = ++currentPtr; 
newNode->c = rand() % 26 + 65;
newNode->listPtr = NULL;

printf("%c->", newNode->c);
}
printf("NULL\n\n");
}

i have noticed that if i remove the while loop and just generate 1 node, the thing executes and terminates fine. could it be that i cant use malloc in a while loop? if so, please explain....

Originally Posted by laserlight

0. You need to indent your code properly.

1. The populate function should probably have a pointer parameter since you want to change the argument.

2. This looks wrong since currentPtr points to a lone object, not an element of an array:

Code:

newNode = ++currentPtr;

3. This is wrong since list1 was not allocated by malloc (or the like):

Code:

free(&list1);

Perhaps you should define a depopulate function instead.

4. sentinel should not be a global variable.

for 3, well, idk why i slapped it in. im fairly sure the memory used at run time clears as you termiate the process. that, and you can increment pointers to point to neighboring linked structs.

i mean, go ahead and copypasta the code into your compiler and run it. it works fine, it just doesn't close properly...

yeah that pointer was pointless (no pun intended). thanks for telling me to remove it, cause now the program works fine