Thread: Trying to learn more about stack/heap/global data

Hey guys, I'm trying to learn more about exactly what C stores on the stack, what it stores on the heap and what is considered global data etc. So any help is greatly appreciated. For example:

Code:

int x = -2;

This is a global variable (not inside a function). Would this be stored on the code/global data memory image section? Or would this go on the stack?

Another question:

Code:

int f(int b)
{
    return b - x;
}

Is the variable b on the stack even though it's a formal parameter and not an actual? Or would it not be pushed onto the stack until used in the return statement of return b - x;?

Thanks for any help guys!

Originally Posted by blernblan

Hey guys, I'm trying to learn more about exactly what C stores on the stack, what it stores on the heap and what is considered global data etc. So any help is greatly appreciated. For example:

Code:

int x = -2;

This is a global variable (not inside a function). Would this be stored on the code/global data memory image section? Or would this go on the stack?

Variable x would be stored in the data segment (initialized).

Originally Posted by blernblan

Another question:

Code:

int f(int b)
{
    return b - x;
}

Is the variable b on the stack even though it's a formal parameter and not an actual? Or would it not be pushed onto the stack until used in the return statement of return b - x;?

Thanks for any help guys!

Parameter variable b would be on the stack and when f() returns its entire frame is popped from the stack.