[2.6] GUI config targets fail with "make O=..."

["Bryan O'Sullivan" <bos@serpentine.com>]

Hi, Sam -

There's something in the 2.6 kbuild infrastructure that does some rather
wrong things for the gconfig and xconfig targets when object files
should go to a separate directory.

It looks like HOSTCXXFLAGS is being mangled somehow.  Here are the
interesting details:

make -C /home/bos/bk/kernel/key O=/tmp/build-i686-smp xconfig

This results in the following invocation of g++, which chokes:

g++ -Wp,-MD,scripts/kconfig/.qconf.o.d  -O2 \
	-I/home/bos/bk/kernel/key//usr/lib/qt-3.1/include \
	-c -o scripts/kconfig/qconf.o \
	/home/bos/bk/kernel/key/scripts/kconfig/qconf.cc

There are two problems here.  The first is the mangling of -I$(QTDIR) so
that it has a bizarre prefix.  The second is that -I$O/scripts/kconfig
is missing, so the compiler can't find the generated file lkc_defs.h
(which is generated correctly).

Any ideas on how to fix this?

	<b