Vladimir Prus wrote:
Sebastian Redl wrote:
What I'm saying is that I believe it to be very dangerous to have your own application use Boost header-only libraries of one version and precompiled libraries that link against other versions of the header-only libraries. If components from the header-only version (say, a shared_ptr or an any) are somehow transferred between the main executable and the library, you're in great danger of crashing.
This is not anything specific to header-only libraries. Classes that are in the public API, regardless of whether the actual implementation is defined inline, or compiled in a separate object file, should not change their layout in point releases, in my opinion.
The issues are not only limited with binary layout. ODR violation problems show with functions too, since due to relocations your application may end up using either old or new versions of them. It is well possible to get a mixed set of them in the end. No need to say that the functions may not behave well in such a zoo and you'll get a big can of worms trying to debug the app. Whenever possible I, personally, try to avoid such situation by all means.