HI all,
I have another query related to virtual destructor in gcc.
In present gcc version 4.4.3 for class for sample program:-
------------------------
class A
{
public:
A()
{
}
virtual ~A();
};
A::~A()
{
}
int main(int argc, char ** argv)
{
A a;
return 0;
}
--------------------------
we have only two branches as:-
-------------------------------------------------------
-: 8: virtual ~A();
-: 9:};
function A::~A() called 1 returned 100% blocks executed 75%
function A::~A() called 0 returned 0% blocks executed 0%
1: 10: A::~A()
-: 11: {
1: 12: }
branch 0 taken 0% (fallthrough)
branch 1 taken 100%
call 2 never executed
call 3 never executed
call 4 never executed
------------------------------------------------------------------
which I has interpreted as :
In virtual destructor there are actually two destructors in which one
takes care about base classes and other about the same class.(am I
correct ??) So to have two branches looks OK
But for same program the result are different in gcc version 4.1.2.The
result contains 6 branches and the output is as :
----------------
8: virtual ~A();
-: 9:};
function A::~A() called 0 returned 0% blocks executed 0%
function A::~A() called 1 returned 100% blocks executed 75%
function A::~A() called 0 returned 0% blocks executed 0%
1: 10: A::~A()
-: 11: {
1: 12: }
branch 0 never executed
branch 1 never executed
call 2 never executed
branch 3 taken 0% (fallthrough)
branch 4 taken 100%
call 5 never executed
branch 6 never executed
branch 7 never executed
call 8 never executed
-: 13
---------------
Can someone tell me the logic about these branches and what optimizer
improvements were done in newer version.
======================
Also in the gcov branch coverage we have something like at end of code :-
------------------------------------
function __static_initialization_and_destruction_0(int, int) called 1
returned 100% blocks executed 100%
function global constructors keyed to main called 1 returned 100% blocks
executed 100%
3: 54:}
branch 0 taken 100% (fallthrough)
branch 1 taken 0%
branch 2 taken 100% (fallthrough)
branch 3 taken 0%
call 4 returned 100%
------------------------------------------------
It is not the part of actual code, why do we have it and what its
significance in terms of branches . Can we omit it from the coverage??
Thanks,
ROHIT
