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Date: Tue, 11 Sep 2012 15:31:39 -0700
Message-ID: <CAGH67wT=7YaiFeWBNvKZOu+BgBPfJncTFM+X01F44eU6pOmrHg@mail.gmail.com>
From: Garrett Cooper <yanegomi@gmail.com>
To: Mark Linimon <linimon@lonesome.com>
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Cc: toolchain@freebsd.org, Dimitry Andric <dim@freebsd.org>,
	current@freebsd.org
Subject: Re: Clang as default compiler November 4th
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On Tue, Sep 11, 2012 at 1:44 PM, Mark Linimon <linimon@lonesome.com> wrote:
> On Tue, Sep 11, 2012 at 10:07:04AM +0100, David Chisnall wrote:
>> There is some logic in the clang driver already for knowing when it is
>> invoked as gcc.  I'd be quite tempted to make gcc a symlink to clang
>> and make clang default to gnu89 when invoked in that way.
>
> And how then does a port say "I don't compile with clang no matter how
> it is invoked"?

Here's one way:

$ clang -dumpspecs
clang: error: unsupported option '-dumpspecs'
clang: error: no input files
$ gcc -dumpspecs | grep -q gcc && echo "gotcha"
gotcha
$

Also,

$ cat Makefile
.if !empty(CC:M*clang*) || !empty(CXX:M*clang*)
IGNORE=         does not compile with clang
.warning ${IGNORE}
.endif

all:
$ make CXX=clang++
"Makefile", line 3: warning: does not compile with clang
$ make CXX=g++
$

But I figured that's probably done elsewhere I bit more sanely.

Thanks,
-Garrett