Re: [PATCH] config: Pass the compiler -Werror during warning detection

[Mark Wielaard <mjw at redhat dot com>]

On Mon, 2016-05-02 at 14:46 -0700, Filipe Brandenburger wrote:
> On Mon, May 2, 2016 at 2:21 PM, Mark Wielaard <mjw@redhat.com> wrote:
> > I am not against this patch if it makes our compiler feature detection
> > better.
> 
> I'd say it makes configure closer to build, considering during build
> time the Makefile is already adding -Werror to most targets.
> Furthermore, the check for -Wlogical-op was already using -Werror as
> well, so I don't see why not have the three others be consistent with
> it (granted, the -Wlogical-op one actually uses non-trivial code,
> while the others just compile a trivial file.)

That makes sense. The -Wlogical-op one was special because we didn't
just want to check that the warning flag was supported, but also that it
didn't produce false positives, which happened with older GCC releases.

> Right now I have to "trick" configure into skipping that test, with:
> 
>   $ ./configure CC=clang-3.5 ac_cv_c99=yes
> 
> And then the build works, at least of libelf/ subdir.
> 
> I hope you agree with my arguments on consistency (-Werror at
> configure vs. build time), but if you feel strongly against this patch
> we do have some possible workarounds (such as passing -Werror in
> CFLAGS of ./configure).

The patch is fine. Pushed it to master.
Just wanted to double check the changes/improvements were deliberate.

Thanks,

Mark