Re: [Qemu-devel] [PATCH v2 000/124] VMState Simplification (Massive)

[Michael S. Tsirkin]

On Sun, Apr 27, 2014 at 10:26:30AM +0200, Paolo Bonzini wrote:
> Il 22/04/2014 13:39, Dr. David Alan Gilbert ha scritto:
> >>>
> >>> I agree.  In many cases, _TEST is a huge review warning sign that
> >>> subsections should have been used instead.
> >I can see how the subsections should be used in some cases, but I've
> >come across at least one case where _TEST was used to avoid the need
> >for a version change.
> >
> >Mst's 9e047b (hw/acpi/piix4.c) replaces an existing field, if a property
> >on the device is set, but if the property is as-before then the structure
> >stays exactly as it was.
> >I can see how that probably should have used a subsection for the new
> >version of the data, but I don't see how it could have otherwise kept
> >it's compatibility.
> 
> Was there really any need to remove the existing field?  Could you
> simply have its contents (probably all zeroes) streamed anyway?
> 
> (Reminds me of "#define union struct /* Wastes some memory */" :)).
> 
> Paolo

Sure, we could do this, I just didn't see the advantage of that
and it seemed cleaner.

-- 
MST