Re: [Qemu-devel] [libvirt] [PULL 25/26] block: Remove deprecated -drive option serial

[Cornelia Huck <cohuck@redhat.com>]

On Thu, 12 Jul 2018 08:51:16 +0200
Markus Armbruster <armbru@redhat.com> wrote:

> Markus Armbruster <armbru@redhat.com> writes:
> 
> > Kevin Wolf <kwolf@redhat.com> writes:
> >  
> >> Am 10.07.2018 um 16:22 hat Cornelia Huck geschrieben:  
> >>> On Tue, 10 Jul 2018 07:59:15 +0200
> >>> Markus Armbruster <armbru@redhat.com> wrote:
> >>>   
> >>> > In addition to actively pulling libvirt developers into review of
> >>> > deprecation patches, we should pursue the idea to optionally let QEMU
> >>> > fail on use of deprecated features, then have libvirt run its test suite
> >>> > that way.  
> >>> 
> >>> What about the following:
> >>> 
> >>> qemu_deprecated_option("old_option", "modern_option");
> >>> 
> >>> Which would then print (in normal operation)
> >>> 
> >>> "WARNING: 'old_option' is deprecated and will be removed; use 'modern_option' instead"
> >>> 
> >>> to the monitor (or to stderr? to both?).
> >>> 
> >>> If you start QEMU with a -no-deprecated-options switch, it would print
> >>> 
> >>> "ERROR: 'old_option' is deprecated and will be removed; use 'modern_option' instead"
> >>> 
> >>> and do an exit(1).
> >>> 
> >>> Would that be workable?  
> >>
> >> I think the function should just take a message:
> >>
> >>     /* Works like error_report(), except for the WARNING/ERROR prefix
> >>      * and exit(1) if -no-deprecated-options is set */
> >>     void deprecation_report(const char *fmt, ...);  
> >
> > I like it.  The contract could use a bit of polish, but that's detail.  
> 
> Suggest --deprecated={silent,warn,error}, default silent.

I like that, but I'd prefer to default to warn (so that command line
users have a better chance to notice it).