Re: [Qemu-devel] [PATCH v2] slirp: Gcc 9 -O3 fix

[Samuel Thibault <samuel.thibault@gnu.org>]

Dr. David Alan Gilbert (git), le lun. 15 avril 2019 13:02:05 +0100, a ecrit:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Gcc 9 needs some convincing that sopreprbuf really is going to fill
> in iov in the call from soreadbuf, even though the failure case
> shouldn't happen.
> 
> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> ---
>  slirp/src/socket.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/slirp/src/socket.c b/slirp/src/socket.c
> index 4a3c935e25..beb8517f1c 100644
> --- a/slirp/src/socket.c
> +++ b/slirp/src/socket.c
> @@ -181,7 +181,7 @@ soread(struct socket *so)
>  	 * 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);
> +	assert(sopreprbuf(so, iov, &n) != 0);

Please make this through a variable, otherwise anybody building with
-DNDEBUG will get sopreprbuf not being called.

>  	nn = recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
>  	if (nn <= 0) {
> @@ -257,6 +257,7 @@ int soreadbuf(struct socket *so, const char *buf, int size)
>  	 * No need to check if there's enough room to read.
>  	 * soread wouldn't have been called if there weren't
>  	 */
> +	assert(size > 0);
>  	if (sopreprbuf(so, iov, &n) < size)
>          goto err;
>  
> -- 
> 2.21.0
>