Re: unwinding of local objects on call stack after throwing and catching an exception

From:
peter koch larsen <peter.koch.larsen@gmail.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Fri, 25 Jan 2008 19:38:41 CST
Message-ID:
<3269358d-9b97-41cd-9bb8-ba3756246859@s13g2000prd.googlegroups.com>
On 25 Jan., 18:52, Ivan Novick <i...@0x4849.net> wrote:

Hi,

If we have a function that has a local automatic object and then it
throws an exception that is caught somewhere up the call stack .....

Does the normal destructor get called for that object? I assume it
has to or else there would be memory leaks everywhere when throwing
exceptions.

for example:

void FOO()
{
  try
  {
   BAR();
  }
  catch(...)
   {
     // do some stuff
     // according to the C++ standard, can we assume o has been
properly destructed at this point?
   }

}

void BAR()
{
   BigHairyObject o;
   throw;

}


I presume you threw something in BAR? If not, your code does not
correspond to your question and your object is not guaranteed to be
destroyed if I remember correctly. std::terminate will be called and
clean-up is implementation defined.
Bu otherwise: Yes - of course! If your compiler does forget the clean-
up you are not using your compiler in a compliant way.

/Peter

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