Re: [PATCH v5 01/18] Makefile: pass CPPFLAGS through to fllow customization

From: Robin H. Johnson <robbat2@gentoo.org>
Date: May 14, 2010, 11:04 UTC
Message-ID: <robbat2-20100514T110034-766521339Z@orbis-terrarum.net>
In-Reply-To: <20100514105832.GB31921@thor.il.thewrittenword.com>

On Fri, May 14, 2010 at 10:58:32AM +0000, Gary V. Vaughan wrote:

Show 6 quoted lines

> As a matter of fact, Automake even jumps through hoops with
> AM_CPPFLAGS to make sure that the package maintainer doesn't
> accidentally trample over the package builder's CPPFLAGS settings - I
> can't think of a scenario where the person who writes the build system
> for a package knows more about what CPPFLAGS the person who builds it
> will need that the person doing the actual building.

AM_CFLAGS != AM_CPPFLAGS. My concern was the mixing of them.

IIRC the correct direction was that all CPPFLAGS should be valid CFLAGS, but not all valid CFLAGS are valid CPPFLAGS (depending on your cpp, they might be passed to other layers).

> I'm pretty sure I'm missing the point though, since letting the
> package builder choose their own CPPFLAGS has been at the core of
> building Unix packages for as long as I can remember...

As a middle ground: CFLAGS = $(OPTCFLAGS) -Wall CPPFLAGS = $(OPTCPPFLAGS) LDFLAGS = $(OPTLDFLAGS) CC = $(OPTCC) AR = $(OPTAR)

(and pass them suitably to the various binaries).

-- 
Robin Hugh Johnson
Gentoo Linux: Developer, Trustee & Infrastructure Lead
E-Mail     : robbat2@gentoo.org
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