[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] slirp: Gcc 9 -O3 fix
From: |
Dr. David Alan Gilbert |
Subject: |
Re: [Qemu-devel] [PATCH] slirp: Gcc 9 -O3 fix |
Date: |
Fri, 12 Apr 2019 16:49:42 +0100 |
User-agent: |
Mutt/1.11.4 (2019-03-13) |
* Samuel Thibault (address@hidden) wrote:
> Hello,
>
> Dr. David Alan Gilbert, le lun. 08 avril 2019 09:46:53 +0100, a ecrit:
> > 'soread' has the comment:
> >
> > /*
> > * No need to check if there's enough room to read.
> > * soread wouldn't have been called if there weren't
> > */
> > sopreprbuf(so, iov, &n);
> >
> > the compiler doesn't realise that, and is moaning about the case
> > where the if (len <=0) return happens and the following
> > code tries to use iov.
>
> I see. Perhaps we should make this an assert then? In case this isn't
> true, i.e. soread() is called even if no room is available, returning 0
> would probably just let the caller just try again, and we should rather
> just plainly crash than hang?
Adding the assert in soread sorts that case out:
assert(sopreprbuf(so, iov, &n) != 0);
however, I also need to fix soreadbuf; is it legal to call that with
a 0 size?
Dave
> Samuel
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK