We’re building a project consisting of 2 shared libraries libProduct and libHelper. libProduct depends on libHelper. We are using a pretty new GCC toolchain (12) for the Linux build in order to leverage C++20 features in our codebase.

Now we need to ship our libraries to a user using an older Raspbian/Debian. First of all he wants to link his application to libProduct, but he also wants to swap out libHelper. The problem is that he uses a much older toolchain – the one coming with Raspbian.

We tried to link our libraries with -static-libstc++ and -static-libgcc and were hoping that this would create more or less self-containing shared libraries, but the observation is:

• libHelper contains a lot of symbols from libstdc++ – that’s expected
• libProduct uses the libstdc++ symbols from libHelper rather than including own copies of the symbols
• the user could not easily swap out libHelper with his own build because his toolchain might not provide some needed symbols in its libstdc++.

How can we solve this and achieve our goals:

• We want to use a new toolchain and libstdc++
• We don’t want to force users to upgrade their toolchain

I know that statically linking libstdc++ to shared libraries is discouraged for various reasons. Still I would like to test it at least. But maybe there’s a better alternative.