diff mbox

CMSG_SPACE() causing compile time error on Mac OS X

Message ID 20160118095855.GC13395@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Daniel P. Berrangé Jan. 18, 2016, 9:58 a.m. UTC 
On Sun, Jan 17, 2016 at 05:23:44PM -0500, Programmingkid wrote:
> I was wondering if you had problems compiling QEMU on Mac OS X recently. On my system, the channel-socket.c file causes this error:
> 
> io/channel-socket.c: In function 'qio_channel_socket_writev':
> io/channel-socket.c:497:18: error: variable-sized object may not be initialized
>      char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };

Can you try applying this patch:



Regards,
Daniel

Comments

Programmingkid Jan. 18, 2016, 2:36 p.m. UTC | #1 
On Jan 18, 2016, at 4:58 AM, Daniel P. Berrange wrote:

> On Sun, Jan 17, 2016 at 05:23:44PM -0500, Programmingkid wrote:
>> I was wondering if you had problems compiling QEMU on Mac OS X recently. On my system, the channel-socket.c file causes this error:
>> 
>> io/channel-socket.c: In function 'qio_channel_socket_writev':
>> io/channel-socket.c:497:18: error: variable-sized object may not be initialized
>>     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };
> 
> Can you try applying this patch:
> 
> diff --git a/io/channel-socket.c b/io/channel-socket.c
> index eaa411f..bc117b1 100644
> --- a/io/channel-socket.c
> +++ b/io/channel-socket.c
> @@ -493,10 +495,12 @@ static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
>     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
>     ssize_t ret;
>     struct msghdr msg = { NULL, };
> -    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };
> +    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
>     size_t fdsize = sizeof(int) * nfds;
>     struct cmsghdr *cmsg;
> 
> +    memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
> +
>     msg.msg_iov = (struct iovec *)iov;
>     msg.msg_iovlen = niov;
> 
> 
> 
> Regards,
> Daniel
> -- 
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Your patch solves the problem. Good job!

Reviewed-By: John Arbuckle <programmingkidx@gmail.com>
Daniel P. Berrangé Jan. 19, 2016, 2:06 p.m. UTC | #2 
On Mon, Jan 18, 2016 at 09:36:08AM -0500, Programmingkid wrote:
> 
> On Jan 18, 2016, at 4:58 AM, Daniel P. Berrange wrote:
> 
> > On Sun, Jan 17, 2016 at 05:23:44PM -0500, Programmingkid wrote:
> >> I was wondering if you had problems compiling QEMU on Mac OS X recently. On my system, the channel-socket.c file causes this error:
> >> 
> >> io/channel-socket.c: In function 'qio_channel_socket_writev':
> >> io/channel-socket.c:497:18: error: variable-sized object may not be initialized
> >>     char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };
> > 
> > Can you try applying this patch:
> > 
> > diff --git a/io/channel-socket.c b/io/channel-socket.c
> > index eaa411f..bc117b1 100644
> > --- a/io/channel-socket.c
> > +++ b/io/channel-socket.c
> > @@ -493,10 +495,12 @@ static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
> >     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
> >     ssize_t ret;
> >     struct msghdr msg = { NULL, };
> > -    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };
> > +    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
> >     size_t fdsize = sizeof(int) * nfds;
> >     struct cmsghdr *cmsg;
> > 
> > +    memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
> > +
> >     msg.msg_iov = (struct iovec *)iov;
> >     msg.msg_iovlen = niov;
> > 
> 
> Your patch solves the problem. Good job!
> 
> Reviewed-By: John Arbuckle <programmingkidx@gmail.com>

Thanks, I'll include this fix in my next PULL request for the io/ layer

Regards,
Daniel
diff mbox

Patch

diff --git a/io/channel-socket.c b/io/channel-socket.c
index eaa411f..bc117b1 100644
--- a/io/channel-socket.c
+++ b/io/channel-socket.c
@@ -493,10 +495,12 @@  static ssize_t qio_channel_socket_writev(QIOChannel *ioc,
     QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
     ssize_t ret;
     struct msghdr msg = { NULL, };
-    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 };
+    char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)];
     size_t fdsize = sizeof(int) * nfds;
     struct cmsghdr *cmsg;
 
+    memset(control, 0, CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS));
+
     msg.msg_iov = (struct iovec *)iov;
     msg.msg_iovlen = niov;