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Date:   Sun, 11 Oct 2020 14:23:36 +0200
From:   Mark Wielaard <mark@klomp.org>
To:     Florian Weimer <fw@deneb.enyo.de>
Cc:     Andi Kleen <andi@firstfloor.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Stephane Eranian <eranian@google.com>,
        linux-toolchains@vger.kernel.org,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Ian Rogers <irogers@google.com>,
        "Phillips, Kim" <kim.phillips@amd.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: Additional debug info to aid cacheline analysis
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On Sun, Oct 11, 2020 at 02:15:18PM +0200, Florian Weimer wrote:
> * Mark Wielaard:
> 
> > Yes, that would work. I don't know what the lowest supported GCC
> > version is, but technically it was definitely fixed in 4.10.0, 4.8.4
> > and 4.9.2. And various distros would probably have backported the
> > fix. But checking for 5.0+ would certainly give you a good version.
> >
> > How about the attached?
> 
> Would it be possible to test for the actual presence of the bug, using
> -fcompare-debug?

Yes, that was discussed in the original commit message, but it was decided
that disabling it unconditionaly was easier. See commit 2062afb4f.

Cheers,

Mark