Optimization of conditional access to globals: thread-unsafe?

[Jason Merrill]

Ian Lance Taylor wrote:
> It appears that the draft C++0x memory model prohibits speculative
> stores.
> 
> Therefore I now think we should aim toward prohibiting them
> unconditionally.

I agree, or perhaps unless the user specifies a flag like 
-fthread-unsafe-opts or something.

> That memory model is just a draft.

It was voted into the C++ standard working paper at the last meeting. 
And the C committee has expressed interest in adopting it, or something 
similar, as well.

Jason