Bela

gcc4.6 that is on the current image does not support some C++11 features.

I tried building gcc4.9 from source on the bbb, but failed at linking time, something about VFP not matching. Also, it was building for armv7l-unknown-linux-gnueabihf rather than arm-linux-gnueabihf. When trying to specify host= and target=arm-linux-gnueabihf it failed. It took ages.
Cross building on Ubuntu was much faster, but it did not build the whole thing ...

So I tried the naughty way http://unix.stackexchange.com/questions/89243/how-to-install-gcc-4-8-1-on-debian-wheezy:
A source to jessie was added to /etc/apt/sources.list:
deb http://ftp.uk.debian.org/debian/ jessie main non-free contrib
at this point I had to fix some issues with keys: http://www.linuxquestions.org/questions/debian-26/there-is-no-public-key-available-for-the-following-key-id-705108/

1. apt-get install debian-keyring debian-archive-keyring
2. apt-key update
   then
3. apt-get update
4. apt-get install gcc g++

this kinda work, but maybe the system is unstable ? will see.