Why does this for loop exit on some platforms and not on others?

Question

I have recently started to learn C and I am taking a class with C as the subject. I\'m currently playing around with loops and I\'m running into some odd behaviour which I d

Answer 1

It is undefined at array[10], and gives undefined behavior as described before. Think about it like this:

I have 10 items in my grocery cart. They are:

0: A box of cereal
1: Bread
2: Milk
3: Pie
4: Eggs
5: Cake
6: A 2 liter of soda
7: Salad
8: Burgers
9: Ice cream

cart[10] is undefined, and may give an out of bounds exception in some compilers. But, a lot apparently don't. The apparent 11th item is an item not actually in the cart. The 11th item is pointing to, what I'm going to call, a "poltergeist item." It never existed, but it was there.

Why some compilers give i an index of array[10] or array[11] or even array[-1] is because of your initialization/declaration statement. Some compilers interpret this as:

• "Allocate 10 blocks of ints for array[10] and another int block. to make it easier, put them right next to each other."
• Same as before, but move it a space or two away, so that array[10] doesn't point to i.
• Do the same as before, but allocate i at array[-1] (because an index of an array can't, or shouldn't, be negative), or allocate it at a completely different spot because the OS can handle it, and it's safer.

Some compilers want things to go quicker, and some compilers prefer safety. It's all about the context. If I was developing an app for the ancient BREW OS (the OS of a basic phone), for example, it wouldn't care about safety. If I was developing for an iPhone 6, then it could run fast no matter what, so I would need an emphasis on safety. (Seriously, have you read Apple's App Store Guidelines, or read up on the development of Swift and Swift 2.0?)