Hi all, the page at http://gcc.gnu.org/projects/cxx0x.html suggests that g++ 4.6 supports range-based "for" (http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2009/n2930.html); however it appears that the construct is actually not recognized in 4.6, and I could find no support for it in gcc/cp/parser.c no cp-tree.def.
Could it be that the support was removed when the Concepts branch was forked? (range-based for was based on concepts previously) Otherwise I would suggest that the C++0x support status page is updated accordingly. Best regards, -- rkp