Re: [libvirt] [PATCH] snapashot: Improve logic of virDomainMomentMoveChildren

s/snapashot/snapshot/

On Thu, Mar 28, 2019 at 09:05:31AM -0500, Eric Blake wrote: > Even though Coverity can prove that 'last' is always set if the prior > loop executed, gcc 8.0.1 cannot: >

> +++ b/src/conf/virdomainmomentobjlist.c > @@ -164,18 +164,17 @@ void > virDomainMomentMoveChildren(virDomainMomentObjPtr from, >                             virDomainMomentObjPtr to) > { > -    virDomainMomentObjPtr child; > -    virDomainMomentObjPtr last; > +    virDomainMomentObjPtr child = from->first_child; > > -    if (!from->first_child) > -        return; From the code-change point-of view, by removing this condition, > -    for (child = from->first_child; child; child = child->sibling) { > +    while (child) { >         child->parent = to; > -        if (!child->sibling) > -            last = child; > +        if (!child->sibling) { > +            child->sibling = to->first_child; > +            break; > +        } > +        child = child->sibling; >     } >     to->nchildren += from->nchildren; > -    last->sibling = to->first_child; >     to->first_child = from->first_child; this possibly erases 'to->first_child' if 'from' does not have any.

But the callers are reasonable and only call this if (from->nchildren)

>     from->nchildren = 0; >     from->first_child = NULL; Reviewed-by: Ján Tomko <jtomko(a)redhat.com&gt;