delete by base class pointer?

[Gernot Frisch]

class Base{};
class Obj : public Base{};

std::vector<Base*> vpBase;
Obj o = new Obj();
vpBase.push_back(&o);

// Can I safely do this: ?
delete vpBase[0];

Thank you,
--
-Gernot
int main(int argc, char** argv) {printf
("%silto%c%cf%cgl%ssic%ccom%c", "ma", 58, 'g', 64, "ba", 46, 10);}

[Peter Koch Larsen]

"Gernot Frisch" <[e-mail]> skrev i en meddelelse
news:30*************@uni-berlin.de...

class Base{};
class Obj : public Base{};

std::vector<Base*> vpBase;
Obj o = new Obj();
vpBase.push_back(&o);

// Can I safely do this: ?
delete vpBase[0];

Thank you,
--
-Gernot
int main(int argc, char** argv) {printf ("%silto%c%cf%cgl%ssic%ccom%c",
"ma", 58, 'g', 64, "ba", 46, 10);}

No - undefined. But for most implementations this will turn out okay. Still
it is a silly example - there's not much going on here.

/Peter

[Karl Heinz Buchegger]

Gernot Frisch wrote:

class Base{};
class Obj : public Base{};

std::vector<Base*> vpBase;
Obj o = new Obj();
vpBase.push_back(&o);

// Can I safely do this: ?
delete vpBase[0];

No. The destructor in the base class has
to be virtual.

class Base
{
public:
virtual ~Base() {}
};

Now you are safe.
--
Karl Heinz Buchegger
kb******@gascad.at

[Gernot Frisch]

"Karl Heinz Buchegger" <kb******@gascad.at> schrieb im Newsbeitrag
news:41***************@gascad.at...

Gernot Frisch wrote:

class Base{};
class Obj : public Base{};

std::vector<Base*> vpBase;
Obj o = new Obj();
vpBase.push_back(&o);

// Can I safely do this: ?
delete vpBase[0];

No. The destructor in the base class has
to be virtual.

class Base
{
public:
virtual ~Base() {}
};

Now you are safe.

Bingo. Now I completele understand 'virtual'. Thank you very much.