I am working on a patch for C::B to fix the following issues for disable compat26 under wxWidgets 2.8.
From wx/toplevel.h (wxWidgets 2.6.1)
// deprecated versions defined for compatibility reasons
#define wxRESIZE_BOX            wxMAXIMIZE_BOX
#define wxTHICK_FRAME           wxRESIZE_BORDER
// obsolete styles, unused any more
#define wxDIALOG_MODAL          0
#define wxDIALOG_MODELESS       0
#define wxNO_3D                 0
#define wxUSER_COLOURS          0
From wx/toplevel.h (wxWidgets cvs head)
#if WXWIN_COMPATIBILITY_2_6
    // deprecated versions defined for compatibility reasons
    #define wxRESIZE_BOX            wxMAXIMIZE_BOX
    #define wxTHICK_FRAME           wxRESIZE_BORDER
    // obsolete styles, unused any more
    #define wxDIALOG_MODAL          0
    #define wxDIALOG_MODELESS       0
    #define wxNO_3D                 0
    #define wxUSER_COLOURS          0
#endif // WXWIN_COMPATIBILITY_2_6