Re: Deprecating arithmetic on std::atomic<void*>

[Jonathan Wakely <jwakely at redhat dot com>]

On 20/04/17 12:07 +0200, Jakub Jelinek wrote:
> On Thu, Apr 20, 2017 at 11:03:38AM +0100, Jonathan Wakely wrote:
> > Yet another case where warning suppression in system headers hurts the
> > library's ability to give diagnostics. We can't warn about using
> > incomplete types in std::unique_ptr because the -Wdelete-incomplete
> > warning gets suppressed, and the interaction of #pragma GCC diagnostic
> > with -Wsystem-headers is ... interesting. We need a way to enable
> > warnings for specific blocks of code, to say "do not suppress warnings
> > here, even though it's in a system header".
>
> Can #pragma GCC warning "-Wno-system-headers" do that?

I don't think so. It didn't work last time I tried to use that to fix
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58876

I don't remember the details, but I think there was some weirdness
like the "pop" didn't restore the old value, or some other class of
warning disappeaed.