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Subject: [Qemu-devel] Re: [PATCH 5/8] ide/pci: convert to qdev.
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To: Juan Quintela <quintela@trasno.org>
Cc: qemu-devel@nongnu.org

On 09/11/09 17:16, Juan Quintela wrote:
> But now we look at savevm.c::vmstate_load_state()
>
>         if (field->flags&  VMS_POINTER) {
>              base_addr = *(void **)base_addr;
>         }
>
> And you see this really nice piece of code.  Each time that we follow a
> pointer, we have to read something for a table, hope that value is
> right, and follow it.
>
> Do you see know why I want to have the minimal amount of pointers
> possible to follow?

No.

Sure, you have to dereference the pointer.  I still don't see a problem 
here.  You seem to think this is fragile.  Why do you think so? 
Typechecking missing somewhere?

> And yes, I understand why you don't want qdev_create_here() idea, I am
> pointing this out to make sure that everybody agrees that not having
> qdev_create_here() and having rest of code use more
> pointers/malloc/... is the right compromise.

I'm sure you'll need VMS_POINTER anyway.  There will be corner cases 
which don't work without.  I think the floppy fifo is one of them.

It is perfectly fine to avoid the pointer indirection if possible.
It isn't the most important thing on earth though.

cheers,
   Gerd