Re: [RFC XEN PATCH] build: Require explicit .config update

[Jan Beulich <jbeulich@xxxxxxxx>]

On 17.09.2025 23:45, Anthony PERARD wrote:
> From: Anthony PERARD <anthony.perard@xxxxxxxxxx>
> 
> It is sometime unwelcome for the config of the hypervisor to change.
> 
> Make output will be something like that:
>   tools/kconfig/conf  --syncconfig Kconfig
> 
>   *** The configuration requires explicit update.
> 
>   make[2]: *** [/xen.git/xen/tools/kconfig/Makefile:73: syncconfig] Error 1
>     GEN     Makefile
>   /xen.git/xen/Rules.mk:19: include/config/auto.conf: No such file or 
> directory
>   make[2]: *** No rule to make target 'include/config/auto.conf'.  Stop.
>   make[1]: *** [/xen.git/xen/Makefile:620: xen] Error 2
>   make: *** [/xen.git/xen/Makefile:179: __sub-make] Error 2
> 
> This also prevent update when the toolchain change and change CONFIG_*
> values like CONFIG_GCC_VERSION.
> 
> Proposed-by: during design session
> Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
> ---
> 
> During the design session, the proposal was to compare .config before
> and after syncconfig. But maybe KCONFIG_NOSILENTUPDATE is enough?

Didn't know something like this existed. It's sufficient imo, just that
we don't want to apply this mode unconditionally.

Jan