GCC 14 newly by default treats as errors a number of situations which
before were only warnings.  For more information see
https://gcc.gnu.org/gcc-14/porting_to.html and meta bug #1220571.

Because of this, package xen fails to compile.  This can be seen online
at:
https://build.opensuse.org/package/live_build_log/openSUSE:Factory:Staging:Gcc7/xen/standard/x86_64

It can be reproduced locally with command: osc build --clean
--alternative-project home:rguenther:nextgcc


The (first) error (that halts the build) is:

[   75s] In file included from
../../../../../newlib-1.16.0/newlib/libc/reent/signalr.c:7:
[   75s] ../../../../../newlib-1.16.0/newlib/libc/reent/signalr.c: In function
‘_kill_r’:
[   75s] ../../../../../newlib-1.16.0/newlib/libc/reent/signalr.c:61:14: error:
implicit declaration of function ‘kill’; did you mean ‘_kill’?
[-Wimplicit-function-declaration]
[   75s]    61 |   if ((ret = _kill (pid, sig)) == -1 && errno != 0)