when is memory allocated for static variable in c++

In C++, memory for static variables is allocated at the start of the program’s execution, before the program enters the main() function. This is part of the initialization phase of the program. Static variables, including static variables declared inside functions or within global scope, are allocated memory in the data segment of the program’s memory space.

Unlike automatic variables (local variables inside functions) that are allocated memory each time the function is called and deallocated when the function exits, static variables persist throughout the program’s execution. Their memory is allocated only once, and they retain their values between function calls.

Here’s an example to illustrate the allocation of memory for a static variable in C++:

#include <iostream>void foo() {    static int count = 0; // Static variable    count++;    std::cout << "Static variable count: " << count << std::endl;}int main() {    foo(); // Output: Static variable count: 1    foo(); // Output: Static variable count: 2    foo(); // Output: Static variable count: 3    // Static variable 'count' retains its value between function calls    return 0;}

In this example, the static variable count is allocated memory when the program starts, and its value is retained and incremented across multiple calls to the foo() function.