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Date: Mon, 20 Apr 2020 21:12:01 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Will Deacon <will@kernel.org>
Cc: Sami Tolvanen <samitolvanen@google.com>, Catalin Marinas
 <catalin.marinas@arm.com>, James Morse <james.morse@arm.com>, Ard
 Biesheuvel <ard.biesheuvel@linaro.org>, Mark Rutland
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Subject: Re: [PATCH v11 01/12] add support for Clang's Shadow Call Stack
 (SCS)
Message-ID: <20200420211201.7fea9561@oasis.local.home>
In-Reply-To: <20200420171727.GB24386@willie-the-truck>
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	<20200420171727.GB24386@willie-the-truck>
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On Mon, 20 Apr 2020 18:17:28 +0100
Will Deacon <will@kernel.org> wrote:

> > +ifdef CONFIG_SHADOW_CALL_STACK
> > +CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
> > +KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
> > +export CC_FLAGS_SCS
> > +endif  
> 
> CFLAGS_SCS would seem more natural to me, although I see ftrace does it this
> way.

The CC_FLAGS_FTRACE was added by Heiko Carstens, and the "CC_FLAGS_"
appears to be a common usage in s390 :-)

That said, I like the CC_FLAGS_ notation, because the Linux build
system uses CFLAGS_* as commands:

  CFLAGS_foo.o = x
  CFLAGS_REMOVE_foo.o = y

And "CC_FLAGS_" is only for new flags and easy to search for.

-- Steve