Re: [libvirt] [PATCH 2/6] virDomainFormatSchedDef: Handle case when func returns NULL

On Tue, May 31, 2016 at 13:32:50 +0200, Michal Privoznik wrote: > On 31.05.2016 13:10, Peter Krempa wrote: >> On Tue, May 31, 2016 at 13:05:16 +0200, Michal Privoznik wrote: >>> On 31.05.2016 12:52, Peter Krempa wrote: >>>> On Tue, May 31, 2016 at 12:33:26 +0200, Michal Privoznik wrote: >>>>> As unlikely as it might seem, func passed to this function can >>>>> return NULL. And in some cases it indeed does so: >>>>> virDomainDefGetVcpuSched and virDomainDefGetIOThreadSched. >>>>> However, the function I'm fixing blindly dereference value func >>>>> returned thus leading to SIGSEGV. >>>> >>>> Same as in the coverity case complaining about this it won't happen here >>>> since we are iterating a known list of items that was collected >>>> beforehand and thus no crashing will happen. >>>> >>> >>> Well, having covery reports a false positive is one thing, being unable >>> to compile is another one. This is what I was afraid of and expressed it >>> here: >>> >>> https://www.redhat.com/archives/libvir-list/2016-May/msg02063.html >>> >>> On the other hand, you use more recent compiler than I do, so you'll hit >>> these error sooner O:-) IOW, one day we will have to deal with this. Again. >> >> I'm thinking of disabling that warning at all since it's making us work >> it around in cases where it clearly doesn't make sense. It's very >> similar to the warning of comparison between signed and unsigned. >> > > Is it? What about the following code: Yes.

> > char *c = NULL; > > *c = 'a'; How about: int a = -1; size_t i; for (i = 0; i < a; i++) do_stuff(i);