Re: Porting issues: Visual Studio and gcc

From:

"Balog Pal" <pasa@lib.hu>

Newsgroups:

comp.lang.c++.moderated

Date:

Wed, 9 Sep 2009 18:32:43 CST

Message-ID:

<h88s8v$1r4h$1@news.ett.com.ua>

"Andrew" <marlow.andrew@googlemail.com>

Yes. The Microsoft compilers turn SEGV etc into C++ exceptions. This
means that catching exceptions by the base class will inadvertantly
catch these cases.

What's the problem here?

I once worked on a program that had a memory corruption bug in it that
triggered during a call to a destructor. The destructor used a try
{...} catch (std::exception& e) {..} to swallow any exceptions that
might occur during cleanup in order to prevent such an exception from
escaping. As we know, to let an exception escape from a destructor
when an exception is already being handled is a no-no. So when this
memory corruption bug triggered the SEGV was silently swallowed. Yes,
these problems really do happen in real life. :-)

Are you sure that was the case? As I recall only catch(...) caught the
extra stuff, not anything named.

And remember that SEGV is produt of undefined behavior -- so crash is
exactly as expectable as continue or landing in a catch() block or at any
place in the code, or just explode the world.

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