What are the limitations on data storage on the stack and why is it not recommended to use it for all variables?

Stack is a region of memory allocated for storing local variables and function calls. The main limitations of data storage on the stack:

• Limited size: The stack usually has a fixed small size (for example, a few megabytes). If too much data is allocated, a stack overflow may occur.
• Lifetime of data: Variables on the stack exist only within the function that created them. After exiting the function, the memory is freed.
• Suitable for small and short-lived data: Large structures or arrays are better stored on the heap.

Why it is not recommended to use the stack for all variables:

• Large objects can lead to stack overflow.
• Data that needs to live longer than the function call should not be stored on the stack.
• For dynamic memory management and large volumes of data, it is better to use the heap.

Example:

func example() {
    var smallValue = 10          // stored on the stack
    let largeArray = [Int](repeating: 0, count: 1000000) // large memory allocated on the heap
}