gcc3 ABI compatibility?

[Michael VanLoon]

Hello

Have there been compatibility-breaking changes to the ABI among the
different versions of gcc3?

In other words, say I build a C++ library with some exported class
interfaces and such. I use a version of gcc3 (maybe 3.4.6), then upgrade it
to a later version of gcc3 (maybe 3.5.1).  Will the libraries break if I
compile new client code against the library built with the older compiler?

I believe this falls into two areas, the name-mangling of the compiler
itself with C++ classes, and the potential changes in libstdc++.

Is there anywhere these ABI-breaking changes are documented?

Thanks!
- Michael