Kevin Kofler (./24922) :
Si c'est compatible au niveau des sources (...) c'est considéré une ABI, pas une API.

N'importe quoi.
http://en.wikipedia.org/wiki/Application_binary_interface

In computer software, an application binary interface (ABI) is the interface between two program modules
, one of which is often a library or operating system, at the level of machine code. An ABI determines such details as how functions are called and in which binary format information should be passed from one program component to the next, or to the operating system in the case of a system call.
(...)
ABIs differ from application programming interfaces (APIs), which similarly define interfaces between program components, but at the source code level.