[PATCH libX11 1/2] xcb_io: Fix Xlib 32-bit request number wrapping

[Julien Cristau]

On Sun, Nov 17, 2013 at 21:30:44 +0100, Jonas Petersen wrote:

> Am 17.11.2013 20:20, schrieb Mouse:
> >>I guess the sizeof comparison would not be necessary since the
> >>condition should never meet with 64-bit longs.
> >Unless it's in a code fragment that's used only on machines with
> ><64-bit longs, it will; X runs on systems with 64-bit longs.
> I meant the condition "dpy->request < dpy->xcb_last_flushed" should
> not meet on systems with 64-bit longs (at least not until the 64-bit
> wrap). So the "sizeof(uint64_t) > sizeof(unsigned long)" would not
> be necessary. It would just increase the overhead on <64-bit
> systems.
> 
The sizeof comparison is a compile-time constant so I'd expect it to be
optimized out by the compiler anyway, so no overhead.

Cheers,
Julien