I know that you don't like #if ... #else ... #endif
but to avoid conflicts in svn update, and as suggested Miguel Gimenez in http://forums.codeblocks.org/index.php/topic,23687.msg161404.html#msg161404 there is Update() to do the job (in main.cpp).
It's possible to use something like :
#if wxCHECK_VERSION(3, 1, 4)
Update();
#else
wxPaintEvent e;
ProcessEvent(e);
#endif // wxCHECK_VERSION
in main.cpp
and :
#if wxCHECK_VERSION(3, 1, 4)
wxPGWindowList const list(NULL);
#else
wxPGWindowList const list;
#endif // wxCHECK_VERSION
return list;
in watchesdlg.cpp.
Note that Update() works also with wxWidgets 3.1.3.