Re: comctl32[2/2]: toolbar: fix the layout of TBUTTON_INFO on Win64

[Mikołaj Zalewski]

Dmitry Timoshkov wrote:
> "Mikołaj Zalewski"  wrote:
> > > > +/* Note: TOOLBAR_DumpButton assumes the layout of the beginning of 
> > > > the structure
> > > > -
> > > > - is the same as of TBBUTTON */
> > > >
> > > > typedef struct
> > > > {
> > > >     INT iBitmap;
> > > > @@ -96,6 +98,9 @@ typedef struct
> > > >     BYTE  fsStyle;
> > > >     BYTE  bHot;
> > > >     BYTE  bDropDownPressed;
> > > > +#ifdef _WIN64
> > > > - BYTE bReserved64[4];
> > > >
> > > > +#endif
> > > >     DWORD_PTR dwData;
> > > >     INT_PTR iString;
> > > >     INT nRow;
> > >
> > > Then probably it would make sense to make TBBUTTON the first member 
> > > of the above
> > > structure. That would help in avoiding possible layout problems in 
> > > future.
> >
> > The bHot and bDropDownPressed would then be called bReserved[0] and 
> > bReserved[1] so this could make more harm than good.
>
> You can make a union for that case, with an appropriate comment.

TBBUTTON is an official Windows API structure. Adding a union inside 
and doing it just because of some internals of our toolbar 
implementation is IMHO not the best idea.

Mikolaj