ABI change when using libsigc++ on an application compiled with c++11 flag

[Didier Roche-Tolomelli]

Reference: https://lists.ubuntu.com/archives/ubuntu-devel/2012-June/035310.html

As unity won't be the only application using C++11 standards on quantal, I guess this ABI change (picked from the STL) depending on build flags should be address.

What can we do here?
- tell that we don't support C++11 applications one quantal
- build those apps with gcc 4.6 -> this, in addition to not be very discoverable, is still introducing a newer using once libsigc++ is rebuilt with gcc 4.7 (Chris is telling that there is no ABI compatibility, even without the c++11 flag)
- shipped two versions of principales librairies (built with gcc 4.7) knowing having ABI incompatbility issues depending with/without the c++11 flag. How we can do this easily? How can we advertize it (I see no automatic solution for picking the right library)?

[Murray Cumming (murrayc)]

Surely this can be closed now that Ubuntu has rebuilt all packages for the new libstdc++ ABI, fixing the issue in general.