Re: [Qemu-devel] [PATCH v4 0/3] Introduce vhost-user-scsi and sample application

[Felipe Franciosi]

> On 2 Mar 2017, at 17:17, Daniel P. Berrange <address@hidden> wrote:
> 
> On Thu, Mar 02, 2017 at 05:01:06PM +0000, Felipe Franciosi wrote:
>> Hi Eric,
>> 
>> Ping on this?
>> http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg06169.html
> 
> [snip]
> 
>>      CC      contrib/ivshmem-client/main.o
>>    
>> /var/tmp/patchew-tester-tmp-naxuy_ku/src/contrib/libvhost-user/libvhost-user.c:
>>  In function ‘vu_panic’:
>>    
>> /var/tmp/patchew-tester-tmp-naxuy_ku/src/contrib/libvhost-user/libvhost-user.c:84:5:
>>  error: ignoring return value of ‘vasprintf’, declared with attribute 
>> warn_unused_result [-Werror=unused-result]
>>         (void)vasprintf(&buf, msg, ap);
>>         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>    cc1: all warnings being treated as errors
> 
> You can side-step the issue entirely by simply not using the vasprintf
> function. Instead do   'buf = g_strdup_vprintf(msg, ap);' - glib does
> abort-on-oom, so there's no error scenario you need to handle.

Thanks for the pointer. That code is in libvhost-user already. I can send a 
separate patch to fix that if you prefer.
Just think that for this kind of usage a simple ignore_value(vasprintf(...)) is 
sufficient; that call is in a panic path already.

There were other cases where ignoring the return value seemed like the 
preferred thing to do.

Felipe

> 
> Regards,
> Daniel
> -- 
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