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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>,
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        Mark Rutland <mark.rutland@arm.com>,
        Masahiro Yamada <masahiroy@kernel.org>,
        Michal Marek <michal.lkml@markovi.net>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
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        Kees Cook <keescook@chromium.org>,
        Laura Abbott <labbott@redhat.com>,
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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