From: Samuel Thibault <samuel.thibault@gnu.org>
To: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: qemu-devel@nongnu.org, jan.kiszka@siemens.com
Subject: Re: [Qemu-devel] [PATCH] slirp: Gcc 9 -O3 fix
Date: Thu, 11 Apr 2019 20:45:02 +0200 [thread overview]
Message-ID: <20190411184502.xvesnriqcocyvuan@function> (raw)
In-Reply-To: <20190408084653.GB2687@work-vm>
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?
Samuel
WARNING: multiple messages have this Message-ID (diff)
From: Samuel Thibault <samuel.thibault@gnu.org>
To: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: jan.kiszka@siemens.com, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] slirp: Gcc 9 -O3 fix
Date: Thu, 11 Apr 2019 20:45:02 +0200 [thread overview]
Message-ID: <20190411184502.xvesnriqcocyvuan@function> (raw)
Message-ID: <20190411184502.YA40qla51cZ5T67N4APaevfoAUsTgBpuzjL760yFlrY@z> (raw)
In-Reply-To: <20190408084653.GB2687@work-vm>
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?
Samuel
next prev parent reply other threads:[~2019-04-11 18:45 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-05 18:46 [Qemu-devel] [PATCH] slirp: Gcc 9 -O3 fix Dr. David Alan Gilbert (git)
2019-04-05 18:46 ` Dr. David Alan Gilbert (git)
2019-04-05 19:08 ` no-reply
2019-04-05 19:08 ` no-reply
2019-04-05 21:25 ` Samuel Thibault
2019-04-05 21:25 ` Samuel Thibault
2019-04-08 8:46 ` Dr. David Alan Gilbert
2019-04-08 8:46 ` Dr. David Alan Gilbert
2019-04-11 18:45 ` Samuel Thibault [this message]
2019-04-11 18:45 ` Samuel Thibault
2019-04-12 15:49 ` Dr. David Alan Gilbert
2019-04-12 15:49 ` Dr. David Alan Gilbert
2019-04-12 21:16 ` Samuel Thibault
2019-04-12 21:16 ` Samuel Thibault
2019-04-15 12:02 ` Dr. David Alan Gilbert
2019-04-15 12:02 ` Dr. David Alan Gilbert
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