Re: [Qemu-devel] [PATCH v2] libvixl: a64: Skip "-Wunused-variable" for gcc 5.0.0 or higher

[Chen Gang <gang.chen.5i5j@gmail.com>]

On 10/12/14 15:50, Peter Maydell wrote:
> On 12 October 2014 01:32, Chen Gang <gang.chen.5i5j@gmail.com> wrote:
>> On 10/12/14 5:25, Peter Maydell wrote:
>>> Some other approaches to this that would confine the
>>> fix to the makefiles rather than requiring us to modify
>>> the vixl source itself:
>>>  a) add a -Wno- option for the affected .o files
>>
>> It is one way, but may have effect with gcc 4 version, and also it is
>> effect with the whole file which is wider than current way.
>>
>>>  b) use -isystem rather than -I to include the libvixl
>>>     directory on the include path
>>>
>>
>> It sounds good to me, although for me, it is not related with current
>> issue.
> 
> -isystem disables a bunch of gcc warnings automatically,
> which is why I suggested it. I'm not overall sure it's
> a great idea though.
> 

OK, thanks. "-isystem" really can skip this warning, originally, I am
not notice about it. :-)

But unlucky, other files within 'libvix' which also include this header
file, also report this warning. So for me, it is not a good idea to let
'-isystem' for the 'libvix' own source files.

Next, I shall firstly confirm whether it is a gcc 5.0 (g++) issue or not
in gcc upstream mailing list.

 - if it is gcc 5.0 issue, I shall try to fix it within this month.

 - else, for me, this patch v2 can still continue.


Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed