When switching to C++11, Is it necessary to recompile all dependency libraries that use STL in interface?

Question

I'm attempting to switch a large project to using C++11. I ran into large number of linker errors which seem caused by the mismatched namespace on STL classes between library compiled with C++11 and those compiled with C++03.

As an example, say library B is a dependency of A. B has following templated class as part of its interface.

template <class Type>
class VectorParameter
{
public:
    VectorParameter();
    virtual ~VectorParameter();

    ...
}

Library A instantiates the template with VectorParameter<std::pair<float, float>>.

When I recompiled A with C++11 without recompiling B, I ran into linker error that complains that

LFE::VectorParameter<std::__1::pair<float, float>>::~VectorParameter() is undefined symbol.

I think the issue here is that library A uses std::__1::pair while B still uses std::pair. Following this reasoning, I assume that I will need to recompile all dependency libraries that refers STL types in their interfaces.

If this is the case, then migrating a large project to C++11 will require all involved groups to switch at the same time, which doesn't seem very practical on a complex project. What would be the best practice for dealing this issue?

Answer 1

It is almost certain that the library header files have changed, therefore to remain in compliance with the One Definition Rule you must recompile everything.

Answer 2

You don't specify your platform or compiler/libraries.

There are some interesting notes here (although a bit out of date) about ABI compatibility for GNU libStdc++ - there is some insulation from ABI compatibility at the expense of true compliance. It rather looks as if it's all or nothing here if you use std::pair.

libc++ (which is clang's standard library) takes another approach and intentionally inserts an extra namespace (I believe called __1) to all of its exported symbols, which means it's possible to link both libstdc++ and libc++ in the same executable. Providing you're not passing STL objects across the boundaries between your old and new libraries, you may well be able to get this to work.