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Date: Wed, 30 Mar 2011 17:45:42 +0200
From: Dimitry Andric <dim@FreeBSD.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Include file search path
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On 2011-03-30 17:26, Nathan Whitehorn wrote:
...
>> During the bootstrap stage, a copy of gcc (or clang) is built, that has
>> all default search paths for headers, libraries, etc, set relative to
>> ${WORLDTMP}, usually /usr/obj/usr/src/tmp.
...
> Since you need to build two compilers anyway (one for the current
> system, to build the new one, and one to live in the new one, linked
> against new libraries), I don't see that it's such a nasty hack.

The building itself is not a problem, of course, and it is even required
if you want to update anything in the toolchain itself.

However, we have added some custom #ifdef FREEBSD_NATIVE parts to
support this feature, so you cannot use stock gcc source to build such a
temporary compiler.  This can be problematic if we ever want to be able
to use toolchains outside of the source tree.