Re: [Qemu-devel] OpenBSD build (was: [PATCH v2] os-posix: Fix build on FreeBSD)

[Blue Swirl <blauwirbel@gmail.com>]

On Sat, May 5, 2012 at 5:08 PM, Andreas Färber <afaerber@suse.de> wrote:
> Am 16.04.2012 09:31, schrieb Gerd Hoffmann:
>> Don't have FreeBSD at hand.  /me has a OpenBSD virtual machine for build
>> tests where this code compiles without issues.
> [snip]
>
> I've now set up an OpenBSD 5.1 VM and it compiles okay. However the
> output is completely chatty due to redundant declarations in the OpenBSD
> system headers.
>
> When I remove -Wredundant-decls from QEMU_CFLAGS it is much better.
>
> Any suggestion how to properly fix this in configure? The QEMU_CFLAGS
> block is before the OS has been checked, and fwiw the flag has been
> around since 2008 (e0e36fe91d2eadcec8159eb6d728c9dd7fc6cf44 / r5931).

Can we have a check whether system headers produce warnings, something
like this:
$ cat headers.c
#include <sys/types.h>
#include <unistd.h>
$ gcc -Wredundant-decls -c headers.c
In file included from headers.c:2:
/usr/include/unistd.h:100: warning: redundant redeclaration of 'lseek'
/usr/include/sys/types.h:210: warning: previous declaration of 'lseek' was here
/usr/include/unistd.h:139: warning: redundant redeclaration of 'ftruncate'
/usr/include/sys/types.h:211: warning: previous declaration of
'ftruncate' was here
/usr/include/unistd.h:164: warning: redundant redeclaration of 'truncate'
/usr/include/sys/types.h:212: warning: previous declaration of
'truncate' was here

>
> Regards,
> Andreas
>
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