Re: [PATCH 4/9] util/oslib-win32: Return NULL on qemu_try_memalign() with zero size

[Richard Henderson]

On 2/27/22 02:54, Peter Maydell wrote:
> > > +    if (size) {
> > > +        ptr = _aligned_malloc(size, alignment);
> > > +    } else {
> > > +        ptr = NULL;
> > > +    }
> >
> > Oh, should we set errno to something here?
> > Otherwise a random value will be used by qemu_memalign.
>
> Yeah, I guess so, though the errno to use isn't obvious. Maybe EINVAL?
>
> The alternative would be to try to audit all the callsites to
> confirm they don't ever try to allocate 0 bytes and then have
> the assert for both Windows and POSIX versions...

Alternately, force size == 1, so that we always get a non-NULL value that can be freed. 
That's a change on the POSIX side as well, of course.


r~