What happens exactly during run time?

[Pranav]

class just{
public :
int x;
just(){ x=1234; }
just(int i){ x = i;}
~just(){ cout << " Here We Are\n" ;}
};

int main()
{
just j1;
just *jptr =new just(5432);

delete( jptr);
delete( &j1);

cout << "Test Out \n" ;

return 0;
}

After executing destructor for J1 program calls for an abort in Visual
Studio 6

[Ian Collins]

Pranav wrote:

class just{
public :
int x;
just(){ x=1234; }
just(int i){ x = i;}
~just(){ cout << " Here We Are\n" ;}
};

int main()
{
just j1;
just *jptr =new just(5432);

delete( jptr);
delete( &j1);

cout << "Test Out \n" ;

return 0;
}

After executing destructor for J1 program calls for an abort in Visual
Studio 6

Well what did you expect? j1 wasn't dynamically allocated.

--
Ian Collins.

[nembo kid]

Pranav ha scritto:

delete( &j1);

Where is its previous new?

[Pranav]

Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

[Ian Collins]

Pranav wrote:

>
Ya I know that thing,

What thing? Keep enough context for your reply to make sense.

But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

What did you expect? You broke the rules by attempting to delete
something that wasn't dynamically allocated, so your runtime barfed.

--
Ian Collins.

[Triple-DES]

On 8 Aug, 12:05, Pranav <pranav...@gmai l.comwrote:

Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

You should not call delete on something that was not allocated using
new (Except the null pointer). jl is an automatic object, so it will
be destroyed automatically.

DP

[HumbleWorker]

On Aug 8, 3:05*pm, Pranav <pranav...@gmai l.comwrote:

Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

The sequence of runtime action for delete (&j1)
is:-

1. The operator delete calls the destructor for the object at the
address &j1. So your cout displays "Here We Are".

2. The second step that the operator delete has to do is free the
memory, but since, the memory in case of &j1 was NOT allocated with
new, a runtime assertion failure is reported.

HW

[Pranav]

On Aug 8, 4:19 pm, HumbleWorker <amardeep.devel [e-mail] rote:

On Aug 8, 3:05 pm, Pranav <pranav...@gmai l.comwrote:

Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

The sequence of runtime action for delete (&j1)
is:-

1. The operator delete calls the destructor for the object at the
address &j1. So your cout displays "Here We Are".

2. The second step that the operator delete has to do is free the
memory, but since, the memory in case of &j1 was NOT allocated with
new, a runtime assertion failure is reported.

HW

Thank You HumbleWorker for complete explanation..,
Do anyone have any link/document to memory allocating function
implementation? (malloc,new,etc ..)

[Rolf Magnus]

Pranav wrote:

On Aug 8, 4:19 pm, HumbleWorker <amardeep.devel [e-mail] rote:

>On Aug 8, 3:05 pm, Pranav <pranav...@gmai l.comwrote:

Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

The sequence of runtime action for delete (&j1)
is:-

1. The operator delete calls the destructor for the object at the
address &j1. So your cout displays "Here We Are".

2. The second step that the operator delete has to do is free the
memory, but since, the memory in case of &j1 was NOT allocated with
new, a runtime assertion failure is reported.

HW

Thank You HumbleWorker for complete explanation..,
Do anyone have any link/document to memory allocating function
implementation? (malloc,new,etc ..)

I have a link:
http://www.google.com/search?q=malloc%20implementation

[tni]

Pranav wrote:

>
Ya I know that thing, But When I call 'delete(&j1)' the destructor for
'j1' is called after this there is window appears saying 'Abort/Ignore/
Retry'. Why exactly this behaviour occurs? Can any one explain what
happens during runtime?

'new' will first call the destructor, then call 'free'. The destructor
will work, 'free' fails, since j1 wasn't allocated on the heap. In the
free call, there is probably an assertion that fails (if you are using
the debug version of the runtime lib) or a memory protection error.