Re: [Qemu-devel] [PATCH] build: disable -Wmissing-braces on older compilers

[Paolo Bonzini]

On 20/10/2017 12:48, Peter Maydell wrote:
> On 20 October 2017 at 11:12, Paolo Bonzini <address@hidden> 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 <address@hidden>
> 
> 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.

Paolo