[libvirt] [PATCHv2] build: avoid warnings on older gcc

[Marcelo Cerri]

On 08/15/2012 04:25 PM, Eric Blake wrote:
> The previous patch pulled in a newer version of stat-time.h from
> gnulib, which tries to suppress some stupid gcc warnings (see
> <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54113>) by exploiting
> a feature of newer gcc.  But we still aim to compile on RHEL 6.3,
> with gcc 4.4.6 (not to mention even older devel platforms like
> RHEL 5), which fails to build thanks to our development -Werror.
>
> It took me a while to figure out how to make our set of warnings
> smaller on older gcc without losing the benefit of the warnings
> when using newer gcc (such as the one on Fedora 17), but this
> should do the trick.
>
> * m4/virt-compile-warnings.m4 (LIBVIRT_COMPILE_WARNINGS): Avoid
> warnings that gnulib can't silence on older gcc.
> ---
>

Tested-by: Marcelo Cerri <mhcerri at linux.vnet.ibm.com>