Code does not work when 'run' ing it but works fine while debugging?

I have a code to convert a number to words(e.g. 31415-->Thirty one thousand four hundred fifteen) The code compiles with no errors/warnings and outputs correctly when debugging. But nothing happens when I 'Run' it. I'm using Code::Blocks. Any help would be appreciated!

Code:

int main (void)
{
int *dataptr = NULL,num,digit_count;
STACK* stack = create();
dataptr = malloc(sizeof(int));
printf("Enter number");
scanf("%d",&num);
while (num!=0)
{
    *dataptr = num%10;
    num = num/10;
    push (stack,dataptr);
    digit_count ++;
};
convert (stack,digit_count);
return 0;

}


void convert (STACK* stack,int digit_count)
{
int* datainptr1=NULL,*datainptr2=NULL;
datainptr1 = (int*)pop(stack);
switch (digit_count)
{
    case 1: //some function
    break;

    case 2:
    {
        if (*datainptr1 == 1)
        {
        datainptr2 = (int*)pop(stack);
        switch (*datainptr2)
        {
            case 1:printf ("Eleven");
            break;
            case 2:printf ("Twelve");
            break;
            case 3:printf ("Thirteen");
            break;
            case 4:printf ("Fourteen");
            break;
            case 5:printf ("Fifteen");
            break;
            case 6:printf ("Sixteen");
            break;
            case 7:printf ("Seventeen");
            break;
            case 8:printf ("Eighteen");
            break;
            case 9:printf ("Nineteen");
            break;
            }
        }
        else
        {
           //more
        }

    }
    break;
}
}

The 'pop' function in a custom header file(for stack simulation) returns a void* by the way. Any ideas on what's wrong?

Local integer digit_count is not initialized, and so when first incremented, is probably much higher (or lower) than 2, and much higher (or lower) than any of the cases in the switch. Running it inside the debugger may mean it is set to 0 for whatever reason. You should initialize it to zero explicitly and see if that makes a difference.

If that works, you should put it back the way it was (uninitialized), throw a printf to report it's value at the very top, and run it in the debugger to see if it does, in fact set everything to zero.

Originally Posted by MK27

Local integer digit_count is not initialized, and so when first incremented, is probably much higher (or lower) than 2, and much higher (or lower) than any of the cases in the switch. Running it inside the debugger may mean it is set to 0 for whatever reason. You should initialize it to zero explicitly and see if that makes a difference.

Thanks a ton! Indeed the debugger set its value to 0 explicitly.! Just about everything other than that variable had been initialized. Amusing how just one glitch can affect a program's output!