Re: [Qemu-devel] [PATCH] configure: Fix build with capabilities

[Peter Maydell]

On 16 July 2012 16:35, Eric Blake <address@hidden> wrote:
> On 07/15/2012 07:54 AM, Stefan Weil wrote:
>> Since commit 417c9d72d48275d19c60861896efd4962d21aca2 all configure tests
>> normally run with -Werror. Some of these tests now fail because they
>> raised a compiler warning.

> Nothing wrong with this patch, per se, but in the Autoconf world, the
> general advice is that programs should check whether -Werror is
> supported, but then avoid using it for the entire remainder of the
> configure script (that is, store the result of -Werror into a different
> variable that gets added into the final CFLAGS at make time, but not
> used during any of the rest of the configure time).  That's because it's
> just too hard to avoid warnings-turned-into-errors for all possible
> versions (including future releases) of gcc, so you are just too likely
> to run into spurious changes in configurations when the next version of
> gcc starts warning about something new if you try to run all your
> configure tests with -Werror.

Hmm, good point -- unlike the actual program compile, failures
due to -Werror inside configure are silent and near-invisible.
Maybe we should back out 417c9d72 ?

-- PMM