destructor is called before copy-constructor on temporary class (allocated on stack during function call) 
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 destructor is called before copy-constructor on temporary class (allocated on stack during function call)


class CUnmanagedA


  do(CUnamanagedB cu)


not working code:

__gc class CManagedA


    do() {  cUnmanagedA1->do(cUnamanagedB1); }


working code:

__gc class CManagedA


    do() {  cUnamanagedB cub1; cUnmanagedA1->do(cub1); }


Within a function call in a managed library I am calling unmanaged code

The instance cUnamanaged2 is passed by value. When I debug this code I see
the following actions:

-copy constructor of cUnamanagedB1 -> cUnamanagedB2

-desctructor ~cUnamanagedB of instance cUnamanagedB2

function CUnmanagedA->do

desctructor of  ~cUnamanagedB for an unknown this pointer.

desctructor of  ~cUnamanagedB for cUnamanagedB2

This means, the destructor is called one time more the constructor, which is
not expected.

If I create an instance before calling the function (see working code)
everything is fine.

For me it looks like if a copy of cUnamanagedB2 was created just by memory
copy but without calling the copy constructor.

In my case CUnamanagedB is a reference counter. Therefore creation and
destruction of objects is important.

I tried to reproduce this error by a simple example, but the behaviour is
different (no copy constructor call at all) and everything is working.

Any ideas or suggestions?

Did I do something wrong?



Mon, 04 Oct 2004 22:27:19 GMT  
 [ 1 post ] 

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