Re: [PATCH 04/13] qemu-kvm: Remove eventfd compat header

Michael S. Tsirkin
2011-07-04T13:34:39Z

On Mon, Jul 04, 2011 at 02:13:36PM +0200, Bernhard Held wrote:
> Am 04.07.2011 12:37, schrieb Michael S. Tsirkin:
> >On Sun, Jul 03, 2011 at 08:31:11PM +0200, Bernhard Held wrote:
> >>SYS_eventfd2 is not defined on systems with old glibc. These numbers
> >>are working for me, for 32 and 64 bit linux. What means
> >>"__NR_eventfd2 does seem to exit"?
> >
> >My system seems to have a definition for the 64 bit
> >_NR_eventfd2 in unistd.h.
> ># grep __NR_eventfd2 /usr/include/*/*h
> >/usr/include/asm-x86_64/unistd.h:#define __NR_eventfd2 290
> >So I think we should use another name to avoid conflicts.
>
> The definition of __NR_eventfd2 is embraced by
>
> #ifndef __NR_eventfd2
> ...
> #endif
>
> which effectively avoids conflicts.

Not if the system header gets included afterwards.

> However the definition of the flags is unconditional, this is indeed buggy.
>
> Best regards,
> Bernhard