[Bug libstdc++/51705] Build infrastructure should not use -std=c++0x until g++ properly supports it

[ed at 80386 dot nl]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51705

--- Comment #2 from Ed Schouten <ed at 80386 dot nl> 2011-12-29 19:42:12 UTC ---
Well, there is the difference. g++ may support C++11 constructs and libstdc++
should be able to use them, but it's wrong to announce __cplusplus == 201103L
to the operating system's headers until it actually does support C++11.

But it could well be the case that changing fixincludes to do the right thing
is sufficient.