Re: [Qemu-devel] [PATCH] bswap: fix compiler warning

[Stefan Weil <sw@weilnetz.de>]

Am 12.04.2013 18:47, schrieb David Gibson:
> On Fri, Apr 12, 2013 at 12:51:51PM +0200, Andreas Färber wrote:
>> Am 12.04.2013 03:41, schrieb Alexey Kardashevskiy:
>>> The bswap functions use memcpy but the bswap.h header itself does not seem to
>>> include it in some configuration such as cross compiling for powerpc64
>>> on x86_64 machine (gcc 4.6.3 from ftp.kernel.org, headers/libs from FC18/ppc64),
>>> the example warning is below.
>>>
>>> The patch explicitly includes string.h.
>>>
>>>   CC    ppc64-softmmu/hw/virtio/virtio.o
>>> In file included from /home/alexey/qemu/include/libfdt_env.h:22:0,
>>>                  from /home/alexey/qemu/../lib4qemu/usr/include/libfdt.h:54,
>>>                  from /home/alexey/qemu/hw/nvram/spapr_nvram.c:25:
>>> /home/alexey/qemu/include/qemu/bswap.h: In function 'lduw_p':
>>> /home/alexey/qemu/include/qemu/bswap.h:244:5: warning: implicit declaration of function 'memcpy' [-Wimplicit-function-declaration]
>>> /home/alexey/qemu/include/qemu/bswap.h:244:5: warning: incompatible implicit declaration of built-in function 'memcpy' [enabled by default]
>>>
>>> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
>>> ---
>>>  include/qemu/bswap.h |    2 ++
>>>  1 file changed, 2 insertions(+)
>>>
>>> diff --git a/include/qemu/bswap.h b/include/qemu/bswap.h
>>> index d3af35d..d50de0d 100644
>>> --- a/include/qemu/bswap.h
>>> +++ b/include/qemu/bswap.h
>>> @@ -1,6 +1,8 @@
>>>  #ifndef BSWAP_H
>>>  #define BSWAP_H
>>>  
>>> +#include <string.h>
>>> +
>>>  #include "config-host.h"
>>>  #include <inttypes.h>
>>>  #include <limits.h>
>> Including string.h is certainly the right thing to do, but why do you
>> single it out first?
> Yeah, it probably shouldn't go above the config header.  Otherwise
> it's the right thing.

If string.h went directly after limits.h, we'd even preserve the
alphabetic order of the system headers :-)