[Bug libstdc++/45133] [c++0x] std::future will crash with NULL deref if get() is called twice

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45133

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Status|SUSPENDED                   |ASSIGNED

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2010-12-03 15:38:53 UTC ---
The latest draft still says this is undefined behaviour, but has a note
encouraging implementations to detect this case and throw.  I am suitably
encouraged.

I'll start by doing that conditionally when _GLIBCXX_DEBUG is defined...