When are static function variables allocated?

Question

I have a question in allocation of memory for static variables. Please look at the following snippet.

#include<stdio.h>
#include<conio.h>

void fun();

static int a;

void main()
{
    fun();
    getch();
}

void fun()
{
    static int b;
}

Can someone please explain me when memory will be allocated for static int b in function fun (before main is executed or when the function is located). I knew that memory for static will be allocated only once, but I want to knew when memory will be allocated for it. Please explain.

I am using 64 bit processor, turbo c compiler, windows 7 operating system.

Answer 1

Memory for static variables is allocated when your program is loaded. Static variables in a function are initialized before the function is called for the first time.

Answer 2

There is no allocation for b in this case. It is an int, and is added to the stack when the application is loaded.

Answer 3

Memory for statics is normally allocated basically as the program loads/just before it starts to execute.

Answer 4

Statics live in the same place as globals. The space for them is set at compile time and allocated at load time.

Answer 5

Memory for static variables (both a and b in the example question) is allocated at compile time. You can verify this by examining your map file. Be aware that, depending on the detail provided in the map file, you may not see the variable name of the static variable, rather simply that the corresponding amount of memory has been allocated. They are initialized when the program is loaded along with the global variables...not the first time the function is called.