--sysroot support

[Joerg Sonnenberger <joerg%britannica.bec.de@localhost>]

Hi all,
newer versions of binutils and GCC have a feature called sysroot,
enabled by passing down --sysroot=$D. This essentially allows prefixes
most builtin path names with $D. Attached patch enables this for
src/tools. It also removes the installation of GCC's own headers since
at least stddef.h doesn't work correctly without patches. The GCC
changes are a bit more nasty since the configure option doesn't allow
enabling it without also hard-coding a value.

This allows compiling a hello world with
        i486--netbsdelf-gcc --sysroot=$DESTDIR hello.c
without having to worry about the many details like the combination of
-nostdinc, -nostdlib, -isysroot, -B etc.

A current build on Linux doesn't change at all with this patch, so I am
reasonable sure that it doesn't create a regression. Patches for using
this can follow later, but I would like to get the support into PCC
first.

Comments?

Joerg

Index: gnu/dist/gcc4/gcc/Makefile.in
===================================================================
RCS file: /home/joerg/repo/netbsd/src/gnu/dist/gcc4/gcc/Makefile.in,v
retrieving revision 1.8
diff -u -p -r1.8 Makefile.in
--- gnu/dist/gcc4/gcc/Makefile.in       12 Aug 2008 10:09:31 -0000      1.8
+++ gnu/dist/gcc4/gcc/Makefile.in       21 Mar 2011 07:26:56 -0000
@@ -3138,19 +3138,7 @@ stmp-int-hdrs: $(STMP_FIXINC) $(USER_H) 
 # Using basename would be simpler, but some systems don't have it.
 # The touch command is here to workaround an AIX/Linux NFS bug.
        -if [ -d include ] ; then true; else mkdir include; chmod a+rx include; 
fi
-       for file in .. $(USER_H); do \
-         if [ X$$file != X.. ]; then \
-           realfile=`echo $$file | sed -e 's|.*/\([^/]*\)$$|\1|'`; \
-           $(STAMP) include/$$realfile; \
-           rm -f include/$$realfile; \
-           cp $$file include; \
-           chmod a+r include/$$realfile; \
-         fi; \
-       done
-       rm -f include/limits.h
-       cp xlimits.h include/limits.h
        cp $(UNWIND_H) include/unwind.h
-       chmod a+r include/limits.h
 # Install the README
        rm -f include/README
        cp $(srcdir)/../fixincludes/README-fixinc include/README
Index: tools/binutils/Makefile
===================================================================
RCS file: /home/joerg/repo/netbsd/src/tools/binutils/Makefile,v
retrieving revision 1.18
diff -u -p -r1.18 Makefile
--- tools/binutils/Makefile     20 Nov 2009 22:51:29 -0000      1.18
+++ tools/binutils/Makefile     21 Mar 2011 09:08:14 -0000
@@ -9,7 +9,8 @@ GNUHOSTDIST=    ${.CURDIR}/../../external/g
 
 BRANDING?=     \
        --with-pkgversion="NetBSD Binutils nb1" \
-       --with-bugurl="http://www.NetBSD.org/support/send-pr.html";
+       --with-bugurl="http://www.NetBSD.org/support/send-pr.html"; \
+       --with-lib-path="=/usr/lib" --with-sysroot
 .else
 BRANDING?=     
 .endif
Index: tools/gcc/Makefile
===================================================================
RCS file: /home/joerg/repo/netbsd/src/tools/gcc/Makefile,v
retrieving revision 1.34
diff -u -p -r1.34 Makefile
--- tools/gcc/Makefile  23 Dec 2009 20:17:13 -0000      1.34
+++ tools/gcc/Makefile  21 Mar 2011 05:23:38 -0000
@@ -34,9 +34,12 @@ CONFIGURE_ARGS=      ${COMMON_CONFIGURE_ARGS}
                --program-transform-name="s,^,${MACHINE_GNU_PLATFORM}-," \
                --enable-languages="${GCC_LANGUAGES}"
 
+GCC_CPPFLAGS=  -DNETBSD_TOOLS -DTARGET_SYSTEM_ROOT=0 \
+               -DTARGET_SYSTEM_ROOT_RELOCATABLE
+
 MAKE_ARGS=     MACHINE= MAKEINFO=${TOOL_MAKEINFO:Q} \
                LIBGCC= LIBGCC1= LIBGCC1_TEST= LIBGCC2= INSTALL_LIBGCC= \
-               EXTRA_PARTS= CPPFLAGS=-DNETBSD_TOOLS \
+               EXTRA_PARTS= CPPFLAGS=${GCC_CPPFLAGS:Q} \
                AR=${HOST_AR:Q} RANLIB=${HOST_RANLIB:Q}
 
 CONFIGURE_ENV+= gcc_cv_libc_provides_ssp=yes