Re: [Qemu-devel] [PATCH 2/2] configure: use pkg-config for obtaining xen version

[Juergen Gross]

On 21/03/17 19:54, Stefano Stabellini wrote:
> On Tue, 21 Mar 2017, Juergen Gross wrote:
>> On 17/03/17 19:33, Stefano Stabellini wrote:
>>> On Fri, 17 Mar 2017, Juergen Gross wrote:
>>>> On 16/03/17 21:20, Stefano Stabellini wrote:
>>>>> On Thu, 16 Mar 2017, Juergen Gross wrote:
>>>>>> Instead of trying to guess the Xen version to use by compiling various
>>>>>> test programs first just ask the system via pkg-config. Only if it
>>>>>> can't return the version fall back to the test program scheme.
>>>>>
>>>>> That's OK, but why did you remove the Xen unstable test?
>>>>
>>>> >From Xen 4.9 on pkg-config will return the needed information. There is
>>>> no longer a need for a test program to determine the Xen version. After
>>>> all this was the main objective of my series adding the pkg-config
>>>> files to Xen.
>>>
>>> I was going to say something like "yeah, but is pkg-config always
>>> available?" In reality, QEMU already has pkg-config as build
>>> dependency, so I guess there is no problem with that.
>>>
>>> Please add a note about this to the commit message.
>>>
>>
>> Okay.
> 
> Sorry to point this out only now, and I realize that it might be
> unimportant for production builds, but it is important to me, and
> developers in general, to be able to test a single QEMU tree against a
> number of Xen trees (all releases from 4.3 onward).
> 
> With this change (specifically dropping the 4.9 build test), out of tree
> builds don't work anymore. I would like to be able to do:
> 
> ./configure --enable-xen --target-list=i386-softmmu \
>                 --extra-cflags="-I$DIR/tools/include \
>                 -I$DIR/tools/libs/toollog/include \
>                 -I$DIR/tools/libs/evtchn/include \
>                 -I$DIR/tools/libs/gnttab/include \
>                 -I$DIR/tools/libs/foreignmemory/include \
>                 -I$DIR/tools/libs/devicemodel/include \
>                 -I$DIR/tools/libxc/include \
>                 -I$DIR/tools/xenstore/include \
>                 -I$DIR/tools/xenstore/compat/include" \
>                 --extra-ldflags="-L$DIR/tools/libxc \
>                 -L$DIR/tools/xenstore \
>                 -L$DIR/tools/libs/evtchn \
>                 -L$DIR/tools/libs/gnttab \
>                 -L$DIR/tools/libs/foreignmemory \
>                 -L$DIR/tools/libs/devicemodel \
>                 -Wl,-rpath-link=$DIR/tools/libs/toollog \
>                 -Wl,-rpath-link=$DIR/tools/libs/evtchn \
>                 -Wl,-rpath-link=$DIR/tools/libs/gnttab \
>                 -Wl,-rpath-link=$DIR/tools/libs/call \
>                 -Wl,-rpath-link=$DIR/tools/libs/foreignmemory \
>                 -Wl,-rpath-link=$DIR/tools/libs/devicemodel" \
>             --disable-kvm 
> make
> 
> And the make should succeed. Is there a way to do that with pkg-config?

Sure, for Xen 4.9 just do:

PKG_CONFIG_PATH=$(DIR)/tools/pkg-config ./configure \
                --enable-xen --target-list=i386-softmmu \
                --disable-kvm
make


Juergen