Re: [boost] [thread] thread_specific_ptr, dangerous conflation of identity and address

Subject: Re: [boost] [thread] thread_specific_ptr, dangerous conflation of identity and address
From: strasser_at_[hidden]
Date: 2010-02-15 17:54:27

Zitat von Edd Dawson <lists_at_[hidden]>:
> The bigger problem though, is that it might not be *their* old data.  
> It can just as easily be someone else's old data due to coincidental  
> alignment of different thread_specific_ptrs on the stack at entirely  
> unrelated points in the program, or even in different libraries that  
> each happen to use boost::thread_specific_ptr!

> It's easy to see the problem here as the calls are very close to one  
> another. In general, however, this strikes me as being really rather  
> dangerous behaviour.
>
> Would it be fair to call it a bug?

I have reported this bug here, including a simpler test case:
https://svn.boost.org/trac/boost/ticket/3837

and posted a (more efficient) implementation of thread_specific_ptr  
which doesn't have this bug here:
http://www.boostpro.com/vault/index.php?action=downloadfile&filename=tss.hpp&directory=&

no reaction from the Boost.Thread maintainer so far.

(it's a prototype: it only supports GCC so far, and IIRC I have fixed  
1 or 2 bugs locally only, without uploading it. so be careful using it.)