libstdc++-v3 stability?

[Benjamin Kosnik]

> Do we have a mechanism to detect such breakage?  

I am not aware of one. There are ABI bits in the g++ testsuite. Perhaps 
something similar could be used?

> Seems like we would
> need to build a suite of dynamically-linked programs (the entire test
> suite perhaps) with g++ 3.1 and then run-time link against the
> libstdc++.so de jour.

This seems like a sane approach, although it's not comprehensive.