[v3] ivshmem-server: ivshmem-client: Build when eventfd() is available

Currently ivshmem requires eventfd() which is Linux specific.
Do not and build it unconditionally on every Linux/BSD/Solaris.

This patch indirectly fixes build failure on NetBSD, where these tools
additionally require -lrt for shm_open(3). In future there should be
added support for NetBSD and the linking addressed appropriately.

Signed-off-by: Kamil Rytarowski <n54@gmx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
---
 configure                            | 2 ++
 contrib/ivshmem-client/Makefile.objs | 2 +-
 contrib/ivshmem-server/Makefile.objs | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

31.05.2017 15:00, Kamil Rytarowski wrote:
> Currently ivshmem requires eventfd() which is Linux specific.
> Do not and build it unconditionally on every Linux/BSD/Solaris.
> 
> This patch indirectly fixes build failure on NetBSD, where these tools
> additionally require -lrt for shm_open(3). In future there should be
> added support for NetBSD and the linking addressed appropriately.

Applied to -trivial, thanks!

/mjt

31.05.2017 15:00, Kamil Rytarowski wrote:
> Currently ivshmem requires eventfd() which is Linux specific.
> Do not and build it unconditionally on every Linux/BSD/Solaris.
> 
> This patch indirectly fixes build failure on NetBSD, where these tools
> additionally require -lrt for shm_open(3). In future there should be
> added support for NetBSD and the linking addressed appropriately.

Unfortunately this breaks static build.

$ ../configure --disable-system --disable-linux-user --static
$ make V=1
...
c++ -I/usr/include/pixman-1  -Werror -pthread -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -m64 -mcx16 -D_GNU_SOURCE
-D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes -Wredundant-decls -Wall -Wundef -Wwrite-strings -Wmissing-prototypes
-fno-strict-aliasing -fno-common -fwrapv  -Wendif-labels -Wno-shift-negative-value -Wno-missing-include-dirs -Wempty-body -Wnested-externs
-Wformat-security -Wformat-y2k -Winit-self -Wignored-qualifiers -Wold-style-declaration -Wold-style-definition -Wtype-limits -fstack-protector-strong
-I/usr/include/libpng16 -I/build/qemu/git/tests -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g  -Wl,--warn-common -m64 -static -g  -o ivshmem-server
libqemuutil.a libqemustub.a   -lm -lgthread-2.0 -pthread -lglib-2.0 -pthread -lpcre -pthread  -lz -lrt -lz -lnettle  -lutil
/usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/crt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
collect2: error: ld returned 1 exit status
Makefile:475: error building «ivshmem-server»
$ _

I'll take a look at this later. reverting it for now.

Thanks,

/mjt

On 05.06.2017 16:29, Michael Tokarev wrote:
> 31.05.2017 15:00, Kamil Rytarowski wrote:
>> Currently ivshmem requires eventfd() which is Linux specific.
>> Do not and build it unconditionally on every Linux/BSD/Solaris.
>>
>> This patch indirectly fixes build failure on NetBSD, where these tools
>> additionally require -lrt for shm_open(3). In future there should be
>> added support for NetBSD and the linking addressed appropriately.
> 
> Unfortunately this breaks static build.
> 
> $ ../configure --disable-system --disable-linux-user --static
> $ make V=1
> ...
> c++ -I/usr/include/pixman-1  -Werror -pthread -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -m64 -mcx16 -D_GNU_SOURCE
> -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -Wstrict-prototypes -Wredundant-decls -Wall -Wundef -Wwrite-strings -Wmissing-prototypes
> -fno-strict-aliasing -fno-common -fwrapv  -Wendif-labels -Wno-shift-negative-value -Wno-missing-include-dirs -Wempty-body -Wnested-externs
> -Wformat-security -Wformat-y2k -Winit-self -Wignored-qualifiers -Wold-style-declaration -Wold-style-definition -Wtype-limits -fstack-protector-strong
> -I/usr/include/libpng16 -I/build/qemu/git/tests -O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -g  -Wl,--warn-common -m64 -static -g  -o ivshmem-server
> libqemuutil.a libqemustub.a   -lm -lgthread-2.0 -pthread -lglib-2.0 -pthread -lpcre -pthread  -lz -lrt -lz -lnettle  -lutil
> /usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/crt1.o: In function `_start':
> (.text+0x20): undefined reference to `main'
> collect2: error: ld returned 1 exit status
> Makefile:475: error building «ivshmem-server»
> $ _
> 
> I'll take a look at this later. reverting it for now.
> 
> Thanks,
> 
> /mjt
> 

I will try to reproduce it locally.

On 5 June 2017 at 15:29, Michael Tokarev <mjt@tls.msk.ru> wrote:
> 31.05.2017 15:00, Kamil Rytarowski wrote:
>> Currently ivshmem requires eventfd() which is Linux specific.
>> Do not and build it unconditionally on every Linux/BSD/Solaris.
>>
>> This patch indirectly fixes build failure on NetBSD, where these tools
>> additionally require -lrt for shm_open(3). In future there should be
>> added support for NetBSD and the linking addressed appropriately.
>
> Unfortunately this breaks static build.
>
> $ ../configure --disable-system --disable-linux-user --static
> $ make V=1
> ...

Why are you trying to build with both system emulation QEMU
and linux-user QEMU disabled anyway? That doesn't leave very
much left to build...

thanks
-- PMM

On Thu, Jun 22, 2017 at 12:54 PM, Peter Maydell
<peter.maydell@linaro.org> wrote:
> On 5 June 2017 at 15:29, Michael Tokarev <mjt@tls.msk.ru> wrote:
[...]
>> $ ../configure --disable-system --disable-linux-user --static
>> $ make V=1
>> ...
>
> Why are you trying to build with both system emulation QEMU
> and linux-user QEMU disabled anyway? That doesn't leave very
> much left to build...

Hmm the only point would be to build libqemuutil.a...

Should the ./configure script return an error if $target_list is empty?