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Date:   Wed, 15 Aug 2018 15:47:10 +0200
From:   Torsten Duwe <duwe@lst.de>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Julien Thierry <julien.thierry@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Ingo Molnar <mingo@redhat.com>,
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        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        live-patching@vger.kernel.org
Subject: Re: [PATCH 1/3] arm64: implement ftrace with regs
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[working on V2 with your feedback]

On Tue, Aug 14, 2018 at 12:04:33PM -0400, Steven Rostedt wrote:
> On Tue, 14 Aug 2018 09:33:52 +0100
> Julien Thierry <julien.thierry@arm.com> wrote:
> > >> Shouldn't this be an error? The option -fpatchable-function-entry has
> > >> been added to the CC_FLAGS_FTRACE, so any call to the compiler is gonna
> > >> break anyway. Or am I missing something?  

This should be the case.

> OK, I see what you mean. If the resulting build wont boot, then yes
> this should be an error and not a warning.

No, there won't be a binary because the first gcc invocation with
CC_FLAGS_FTRACE will error out.

The alternatives are a makefile-warning followed by a gcc-error or just
a makefile-error. The makefile warning or error should hint at the causing
config option, that's the key point. Beyond that I don't have any preference.

	Torsten