HB_EXTERN hb_font_t * hb_coretext_font_create(CTFontRef ct_font)
HB_EXTERN hb_face_t * hb_coretext_face_create(CGFontRef cg_font)
HB_EXTERN CGFontRef hb_coretext_face_get_cg_font(hb_face_t *face)
HB_EXTERN CTFontRef hb_coretext_font_get_ct_font(hb_font_t *font)