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class foo
{
    foo(){}; //constructor;
    ~foo(){}; //destructor;
    void bar(void){}
};

void func1(){
    foo foo_obj;
}

int main(void)
{
    func1();
    //Does the destructor for the foo object initialized in here get called?
    {
        foo foo_obj2
        //This var was initialized in its own block. Will the destructor be called?
    }
};

Code: Select all

class foo
{
    foo(){}; //constructor;
    ~foo(){}; //destructor;
    void bar(void){}
};

void func1(){
    foo foo_obj;
}

int main(void)
{
    func1();
    //Does the destructor for the foo object initialized in here get called?
    {
        foo foo_obj2
        //This var was initialized in its own block. Will the destructor be called?
    }
};

Code: Select all

--> enter main()
  --> enter func1()
      call constructor foo::foo() for object foo_obj, created on the stack.
      call destructor  foo::~foo() for object foo_obj.
  <-- leave func1()

  --> start scoping block {
     call constructor foo:foo() for object foo_obj2, created on the stack.
     call destructor foo::~foo() for object foo_obj2.
  <-- leave scoping block }
<-- leave main()

Code: Select all

/* This variable will probably not be 5000 when you enter your entry point. */
int MyGlobalVar = 5000;

/* Random function. */
void foo()
{
   /* This variable is locally declared and allocated on the stack, as JamesM said. It should have value '2000' as expected. */
   int SomeVar = 2000;
}

int main()
{
   foo();
}

Code: Select all

int MyGlobalVar;

void InitializeGlobalVars()
{
   MyGlobalVar = 2000;
   /* ... */
}

int main()
{
   InitializeGlobalVars();
}

Code: Select all

; Note that these are declared in the linker script with the same names.
[EXTERN LdConstrStart]
[EXTERN LdConstrEnd]

ExecConstr:
	push ebx					; Preserve EBX contents.

	mov ebx, LdConstrStart		; Load the first constructor.
	jmp .Compare				; Jump to the compare label.
	
	.Body:						; This is the body, it calls the constructor and increments the 'pointer'.
		call [ebx]				; Call the constructor.
		add ebx, 4				; Move to the next one.
	
	.Compare:					; This checks if we've reached the end of the constructor 'list'.
		cmp ebx, LdConstrEnd	; Check if the constructor inside ebx is the last constructor.
		jb .Body				; If it isn't, go back to Body.
		
	pop ebx						; Return EBX to its old state.
	ret							; Return, we're done here.