[infinispan-dev] ABI compatibility of C++ client

[Radim Vansa]

Hi guys,

as I've tried to get rid of all the warnings emitted in Windows build of 
C++ HotRod client, I've noticed that the ABI of this library is not very 
well designed.
I am not an expert for this kind of stuff, but many sources I've found 
say that exporting STL containers (such as string or vector, or 
shared_ptr) is not ABI-safe.

For windows, the STL export is allowed [1] when both library and user 
application is linked against the same version of CRT. I am really not 
sure whether we want to force it to the user, and moreover, due to bug 
in VC10 implementation of STL [2] we can't explicitly export shared_ptr 
(I haven't found any workaround for that so far).

Regarding the GCC-world, situation is not better. The usual response for 
exporting STL classes is "don't do that". It is expected that these 
trouble will be addressed in C++17 (huh :)).

What can we do about that? Fixing this requires a lot of changes in 
API... can we afford to do that now? Or will we just declare "compile 
with the same versions and compile options as we did"? (we should state 
them, then)

I have only limited knowledge of the whole C++ ecosystem, if I am wrong, 
I'd be gladly corrected.

Radim

[1] http://support.microsoft.com/kb/168958
[2] http://connect.microsoft.com/VisualStudio/feedback/details/649531

-- 
Radim Vansa <rvansa at redhat.com>
JBoss DataGrid QA