[Bug libstdc++/47380] concept checking and incomplete types

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47380

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-01-20 
17:42:17 UTC ---
I'll fix the outdated reference to concepts in the docs though