[Bug libstdc++/58729] tr2::dynamic_bitset::resize fails

[3dw4rd at verizon dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58729

--- Comment #6 from Ed Smith-Rowland <3dw4rd at verizon dot net> ---
Created attachment 31017
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31017&action=edit
Patch dynamic_bitset...

Here is the patch.  I did a little extra work to move large functions offline
and to fix other things that were broken.  This class was dumped in before it
was ready really.

tested on x86_64-linux.

I tried retesting this morning but it looks like bootstrap is broken.

See what you think.