Re: gdb help: debugging a segfault in boost::shared_ptr

phear wrote:
Putting a lock on IDatabaseAdapter.GetAdapter() did not help. Locking
Instance::GetEntry fixed it, but this ofcourse defies the purpose of
multi-threading.

I have tried using normal pointers instead, and although a lot more
rare, it still segfaults occasionally.

I am currently following a lead from valgrind, but I'm not going to
hold my breath just yet.

[...]

It's not a problem with shared_ptr or with the debugger. The "lock-free"
stuff in shared_ptr is a red herring. It's an implementation issue to make
it thread-safe and could just have easily been lock based and is lock
based on some platforms. Thread-safe means that shared_ptr handle
internally shared data safely, i.e. the reference count. It does not
mean it is atomically thread-safe like Java pointers and that you
don't need some form of external synchronization if the pointers are
shared.

If you want to see what an atomically thread-safe refcount pointer looks
like, take a look at atomic_ptr in
http://atomic-ptr-plus.sourceforge.net/

We can't give you too much specific advice on how to solve your
problem since we know few specifics on what you are trying
to accomplish.


--
Joe Seigh

When you get lemons, you make lemonade.
When you get hardware, you make software. .

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