Building Xen 4.14 on Debian Bullseye (WAS Re: Xen compile error)

[Julien Grall <julien@xxxxxxx>]

Hi,

Thank you for the report.

On 08/10/2020 13:28, ba1020@xxxxxxxxxxxxx wrote:
> i try to compile the lates Release 4.14.0 and get stuck here
In general, I would suggest to use the branch stable-4.14 or 
staging-4.14 as we may have fixed some bugs which unfortunately slipped 
in the release.
However, for your situation, this would have unfortunately not helped 
because the commit d25cc3ec93eb "libxl: workaround gcc 10.2 
maybe-uninitialized warning" is not present.
I know that Debian is looking to get Xen 4.14 build with the GCC 10. I 
have CCed Ian and Hans who may be able to assist you if you encounter 
more bug.
In regard to upstream, I think we want to get 4.14 building out-of-box 
with GCC 10 so distros can easily adopt it.
I will send an e-mail to request a backport for the commit d25cc3ec93eb 
"libxl: workaround gcc 10.2 maybe-uninitialized warning".
Best regards,

> libxlu_pci.c: In function ‘xlu_pci_parse_bdf’:
> libxlu_pci.c:32:18: error: ‘func’ may be used uninitialized in this function 
> [-Werror=maybe-uninitialized]
>     32 |     pcidev->func = func;
>        |     ~~~~~~~~~~~~~^~~~~~
> libxlu_pci.c:51:29: note: ‘func’ was declared here
>     51 |     unsigned dom, bus, dev, func, vslot = 0;
>        |                             ^~~~
> libxlu_pci.c:31:17: error: ‘dev’ may be used uninitialized in this function 
> [-Werror=maybe-uninitialized]
>     31 |     pcidev->dev = dev;
>        |     ~~~~~~~~~~~~^~~~~
> libxlu_pci.c:51:24: note: ‘dev’ was declared here
>     51 |     unsigned dom, bus, dev, func, vslot = 0;
>        |                        ^~~
> libxlu_pci.c:30:17: error: ‘bus’ may be used uninitialized in this function 
> [-Werror=maybe-uninitialized]
>     30 |     pcidev->bus = bus;
>        |     ~~~~~~~~~~~~^~~~~
> libxlu_pci.c:51:19: note: ‘bus’ was declared here
>     51 |     unsigned dom, bus, dev, func, vslot = 0;
>        |                   ^~~
> libxlu_pci.c:29:20: error: ‘dom’ may be used uninitialized in this function 
> [-Werror=maybe-uninitialized]
>     29 |     pcidev->domain = domain;
>        |     ~~~~~~~~~~~~~~~^~~~~~~~
> libxlu_pci.c:51:14: note: ‘dom’ was declared here
>     51 |     unsigned dom, bus, dev, func, vslot = 0;
>        |              ^~~
> cc1: all warnings being treated as errors
> make[5]: *** [/home/adminjs/xen/tools/libxl/../../tools/Rules.mk:216: 
> libxlu_pci.o] Error 1
> make[5]: *** Waiting for unfinished jobs....
> make[5]: Leaving directory '/home/adminjs/xen/tools/libxl'
> make[4]: *** [/home/adminjs/xen/tools/../tools/Rules.mk:240: 
> subdir-install-libxl] Error 2
> make[4]: Leaving directory '/home/adminjs/xen/tools'
> make[3]: *** [/home/adminjs/xen/tools/../tools/Rules.mk:235: subdirs-install] 
> Error 2
> make[3]: Leaving directory '/home/adminjs/xen/tools'
> make[2]: *** [Makefile:72: install] Error 2
> make[2]: Leaving directory '/home/adminjs/xen/tools'
> make[1]: *** [Makefile:134: install-tools] Error 2
> make[1]: Leaving directory '/home/adminjs/xen'
> make: *** [Makefile:170: world] Error 2

--
Julien Grall