If you feed it a file that was saved in some other local encoding, then since it has no way of knowing htat, it'll stop parsing when it hits some bytes that aren't valid UTF8.
I guess I could add some fallback checks that would force it to carry on parsing after it hits UTF8 errors, but even if it did that, it'd screw up the extended characters.
If it could help someone here is my method, to avoid messing source files because of encoding:
1) I installed "fix file encoding" plugin inside visual studio and I asked he protects every file.
2) inside Introjucer, each time a new .h or .cpp is created, I put a comment with a special character as 'à' for example, at the beginning of the file, and I save it with introjucer.
3) Then, when the file is opened inside visual studio, the file is by default considered as
being encoded in UTF8, and I could resave it normally without I need to specify the UTF8 encoding mode each time I save it.