This one is needed to build QEMU 2.11.x on Ubuntu 18.04.
On Wed, 20 Dec 2017 18:14:13 +0100
Paolo Bonzini <pbonzini@redhat.com> wrote:
> Recent glibc added memfd_create in sys/mman.h. This conflicts with
> the definition in util/memfd.c:
>
> /builddir/build/BUILD/qemu-2.11.0-rc1/util/memfd.c:40:12: error: static declaration of memfd_create follows non-static declaration
>
> Fix the configure test, and remove the sys/memfd.h inclusion since the
> file actually does not exist---it is a typo in the memfd_create(2) man
> page.
>
> Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> configure | 2 +-
> util/memfd.c | 4 +---
> 2 files changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/configure b/configure
> index 9c8aa5a..99ccc17 100755
> --- a/configure
> +++ b/configure
> @@ -3923,7 +3923,7 @@ fi
> # check if memfd is supported
> memfd=no
> cat > $TMPC << EOF
> -#include <sys/memfd.h>
> +#include <sys/mman.h>
>
> int main(void)
> {
> diff --git a/util/memfd.c b/util/memfd.c
> index 4571d1a..412e94a 100644
> --- a/util/memfd.c
> +++ b/util/memfd.c
> @@ -31,9 +31,7 @@
>
> #include "qemu/memfd.h"
>
> -#ifdef CONFIG_MEMFD
> -#include <sys/memfd.h>
> -#elif defined CONFIG_LINUX
> +#if defined CONFIG_LINUX && !defined CONFIG_MEMFD
> #include <sys/syscall.h>
> #include <asm/unistd.h>
>