On 10/20/17 13:02, Paolo Bonzini wrote:
> On 20/10/2017 12:48, Peter Maydell wrote:
>> On 20 October 2017 at 11:12, Paolo Bonzini <pbonz...@redhat.com> wrote:
>>> GCC 4.9 and newer stopped warning for missing braces around the
>>> "universal" C zero initializer {0}. One such initializer sneaked
>>> into scsi/qemu-pr-helper.c and is breaking the build with such
>>> older GCC versions.
>>>
>>> Detect the lack of support for the idiom, and disable the warning
>>> in that case.
>>>
>>> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
>>
>> AFAIK "{}" will work and not be warned about anywhere (we
>> use it extensively already) so you don't need to fall back to
>> memset...
>
> Doh, of course that will work in scsi/qemu-pr-helper.c. In general you
> can use {0} but not {} to initialize a scalar, like
>
> IDontKnowIfItsAnArrayOrPointer x = {}; //might fail
> IDontKnowIfItsAnArrayOrPointer x = {0}; //always works
>
> I'm not sure if that matters.
My remark below might matter even less, but:
I'd find it regrettable if we suppressed a wrong gcc warning about a
valid C construct by replacing the construct with a GNU-ism that is
*not* standard C. :/
Laszlo
