diff -ud -Nrud gcc-4.8.1/config.sub gcc-4.8.1/config.sub
--- gcc-4.8.1/config.sub	2013-01-11 14:02:58.000000000 +0100
+++ gcc-4.8.1/config.sub	2013-07-12 09:10:19.136870930 +0200
@@ -1369,6 +1369,7 @@
 	      | -udi* | -eabi* | -lites* | -ieee* | -go32* | -aux* \
 	      | -chorusos* | -chorusrdb* | -cegcc* \
 	      | -cygwin* | -msys* | -pe* | -psos* | -moss* | -proelf* | -rtems* \
+	      | -helenos \
 	      | -mingw32* | -mingw64* | -linux-gnu* | -linux-android* \
 	      | -linux-newlib* | -linux-musl* | -linux-uclibc* \
 	      | -uxpv* | -beos* | -mpeix* | -udk* \
diff -ud -Nrud gcc-4.8.1/gcc/config.gcc gcc-4.8.1/gcc/config.gcc
--- gcc-4.8.1/gcc/config.gcc	2013-03-13 10:47:41.000000000 +0100
+++ gcc-4.8.1/gcc/config.gcc	2013-07-12 13:20:08.321208280 +0200
@@ -624,7 +624,7 @@
   # need_64bit_hwint=yes # system compiler has this for all arch!
   use_gcc_stdint=wrap
   ;;
-*-*-linux* | frv-*-*linux* | *-*-kfreebsd*-gnu | *-*-knetbsd*-gnu | *-*-gnu* | *-*-kopensolaris*-gnu)
+*-*-linux* | frv-*-*linux* | *-*-kfreebsd*-gnu | *-*-knetbsd*-gnu | *-*-gnu* | *-*-kopensolaris*-gnu | *-helenos*)
   extra_options="$extra_options gnu-user.opt"
   gas=yes
   gnu_ld=yes
@@ -642,7 +642,7 @@
   # glibc / uclibc / bionic switch.
   # uclibc and bionic aren't usable for GNU/Hurd and neither for GNU/k*BSD.
   case $target in
-    *linux*)
+    *linux* | *helenos*)
       extra_options="$extra_options linux.opt";;
   esac
   case $target in
@@ -663,7 +663,7 @@
   use_gcc_stdint=wrap
   # Add Android userspace support to Linux targets.
   case $target in
-    *linux*)
+    *linux* | *helenos*)
       tm_file="$tm_file linux-android.h"
       extra_options="$extra_options linux-android.opt"
       ;;
@@ -681,6 +681,10 @@
   cxx_target_objs="${cxx_target_objs} glibc-c.o"
   tmake_file="${tmake_file} t-glibc"
   target_has_targetcm=yes
+  # HelenOS
+  case $target in
+    *-helenos*) tm_file="$tm_file helenos.h" ;;
+  esac
   ;;
 *-*-netbsd*)
   tmake_file="t-slibgcc"
@@ -868,7 +872,7 @@
 	extra_options="${extra_options} netbsd.opt netbsd-elf.opt"
 	tmake_file="${tmake_file} arm/t-arm"
 	;;
-arm*-*-linux-*)			# ARM GNU/Linux with ELF
+arm*-*-linux-* | arm*-helenos-*)			# ARM GNU/Linux with ELF
 	tm_file="dbxelf.h elfos.h gnu-user.h linux.h linux-android.h glibc-stdint.h arm/elf.h arm/linux-gas.h arm/linux-elf.h"
 	case $target in
 	arm*b-*-linux*)
@@ -890,6 +894,12 @@
 	# The EABI requires the use of __cxa_atexit.
 	default_use_cxa_atexit=yes
 	with_tls=${with_tls:-gnu}
+	# HelenOS
+	# (Strangely, tm_file ignores the defaults loaded previously and
+	# we need to add helenos.h one more time.)
+	case $target in
+	*-helenos*) tm_file="$tm_file helenos.h arm/helenos-arm32.h arm/helenos.h" ;;
+	esac
 	;;
 arm*-*-uclinux*eabi*)		# ARM ucLinux
 	tm_file="dbxelf.h elfos.h arm/unknown-elf.h arm/elf.h arm/linux-gas.h arm/uclinux-elf.h glibc-stdint.h"
@@ -1257,12 +1267,12 @@
 	gas=yes
 	gnu_ld=yes
 	;;
-i[34567]86-*-linux* | i[34567]86-*-kfreebsd*-gnu | i[34567]86-*-knetbsd*-gnu | i[34567]86-*-gnu* | i[34567]86-*-kopensolaris*-gnu)
+i[34567]86-*-linux* | i[34567]86-*-kfreebsd*-gnu | i[34567]86-*-knetbsd*-gnu | i[34567]86-*-gnu* | i[34567]86-*-kopensolaris*-gnu | i[34567]86-*-helenos)
 			# Intel 80386's running GNU/*
 			# with ELF format using glibc 2
 	tm_file="${tm_file} i386/unix.h i386/att.h dbxelf.h elfos.h gnu-user.h glibc-stdint.h"
 	case ${target} in
-	i[34567]86-*-linux*)
+	i[34567]86-*-linux* | i[34567]86-*-helenos)
 		tm_file="${tm_file} linux.h"
 		# Assume modern glibc
 		default_gnu_indirect_function=yes
@@ -1318,12 +1328,16 @@
 		tm_file="$tm_file i386/gnu-user-common.h i386/gnu-user.h gnu.h i386/gnu.h"
 		;;
 	esac
+	# HelenOS
+	case $target in
+	*-helenos*) tm_file="$tm_file i386/helenos-ia32.h i386/helenos.h" ;;
+	esac
 	;;
-x86_64-*-linux* | x86_64-*-kfreebsd*-gnu | x86_64-*-knetbsd*-gnu)
+x86_64-*-linux* | x86_64-*-kfreebsd*-gnu | x86_64-*-knetbsd*-gnu | x86_64-*-helenos)
 	tm_file="${tm_file} i386/unix.h i386/att.h dbxelf.h elfos.h gnu-user.h glibc-stdint.h \
 		 i386/x86-64.h i386/gnu-user-common.h i386/gnu-user64.h"
 	case ${target} in
-	x86_64-*-linux*)
+	x86_64-*-linux* | x86_64-*-helenos)
 		tm_file="${tm_file} linux.h i386/linux-common.h i386/linux64.h"
 		# Assume modern glibc
 		default_gnu_indirect_function=yes
@@ -1359,6 +1373,10 @@
 		esac
 	done
 	TM_MULTILIB_CONFIG=`echo $TM_MULTILIB_CONFIG | sed 's/^,//'`
+	# HelenOS
+	case $target in
+	*-helenos*) tm_file="$tm_file i386/helenos-amd64.h i386/helenos.h" ;;
+	esac
 	;;
 i[34567]86-pc-msdosdjgpp*)
 	xm_file=i386/xm-djgpp.h
@@ -1567,10 +1585,14 @@
 	target_cpu_default="MASK_GNU_AS|MASK_GNU_LD"
 	tmake_file="${tmake_file} ia64/t-ia64"
 	;;
-ia64*-*-linux*)
+ia64*-*-linux* | ia64-*-helenos)
 	tm_file="${tm_file} dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h ia64/sysv4.h ia64/linux.h"
 	tmake_file="${tmake_file} ia64/t-ia64 ia64/t-linux t-libunwind"
 	target_cpu_default="MASK_GNU_AS|MASK_GNU_LD"
+	# HelenOS
+	case $target in
+	*-helenos*) tm_file="$tm_file ia64/helenos-ia64.h ia64/helenos.h" ;;
+	esac
 	;;
 ia64*-*-hpux*)
 	tm_file="${tm_file} dbxelf.h elfos.h ia64/sysv4.h ia64/hpux.h"
@@ -1794,7 +1816,7 @@
 	gas=yes
 	test x$with_llsc != x || with_llsc=yes
 	;;
-mips64*-*-linux* | mipsisa64*-*-linux*)
+mips64*-*-linux* | mipsisa64*-*-linux* | mips64*-*-helenos)
 	tm_file="dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h ${tm_file} mips/gnu-user.h mips/gnu-user64.h mips/linux64.h mips/linux-common.h"
 	tmake_file="${tmake_file} mips/t-linux64"
 	tm_defines="${tm_defines} MIPS_ABI_DEFAULT=ABI_N32"
@@ -1814,8 +1836,12 @@
 	gnu_ld=yes
 	gas=yes
 	test x$with_llsc != x || with_llsc=yes
+	# HelenOS
+	case $target in
+	*-helenos*) tm_file="$tm_file mips/helenos-mips64el.h mips/helenos.h" ;;
+	esac
 	;;
-mips*-*-linux*)				# Linux MIPS, either endian.
+mips*-*-linux* | mips*-*-helenos)	# Linux MIPS, either endian.
         tm_file="dbxelf.h elfos.h gnu-user.h linux.h glibc-stdint.h ${tm_file} mips/gnu-user.h mips/linux.h"
 	if test x$enable_targets = xall; then
 		tm_file="${tm_file} mips/gnu-user64.h mips/linux64.h"
@@ -1830,6 +1856,11 @@
 		tm_defines="${tm_defines} MIPS_ISA_DEFAULT=32"
         esac
 	test x$with_llsc != x || with_llsc=yes
+	# HelenOS
+	case $target in
+	mipsel-*-helenos*) tm_file="$tm_file mips/helenos-mips32el.h mips/helenos.h" ;;
+	mips-*-helenos*) tm_file="$tm_file mips/helenos-mips32eb.h mips/helenos.h" ;;
+	esac
 	;;
 mips*-mti-elf*)
 	tm_file="elfos.h newlib-stdint.h ${tm_file} mips/elf.h mips/sde.h mips/mti-elf.h"
@@ -2066,7 +2097,7 @@
 	extra_options="${extra_options} rs6000/sysv4.opt"
 	tmake_file="rs6000/t-fprules rs6000/t-rtems t-rtems rs6000/t-ppccomm"
 	;;
-powerpc-*-linux* | powerpc64-*-linux*)
+powerpc-*-linux* | powerpc64-*-linux* | powerpc*-*-helenos)
 	tm_file="${tm_file} dbxelf.h elfos.h freebsd-spec.h rs6000/sysv4.h"
 	extra_options="${extra_options} rs6000/sysv4.opt"
 	tmake_file="rs6000/t-fprules rs6000/t-ppcos ${tmake_file} rs6000/t-ppccomm"
@@ -2079,7 +2110,7 @@
 	    powerpc-*-linux*spe* | powerpc-*-linux*paired*)
 		maybe_biarch=
 		;;
-	    powerpc64-*-linux*)
+	    powerpc64-*-linux* | powerpc64-*-helenos)
 	    	test x$with_cpu != x || cpu_is_64bit=yes
 		maybe_biarch=always
 		;;
@@ -2112,6 +2143,11 @@
 	if test x${enable_secureplt} = xyes; then
 		tm_file="rs6000/secureplt.h ${tm_file}"
 	fi
+	# HelenOS
+	case $target in
+	powerpc-*-helenos*) tm_file="$tm_file rs6000/helenos-ppc32.h rs6000/helenos.h" ;;
+	powerpc64-*-helenos*) tm_file="$tm_file rs6000/helenos-ppc64.h rs6000/helenos64.h" ;;
+	esac
 	;;
 powerpc-wrs-vxworks|powerpc-wrs-vxworksae)
 	tm_file="${tm_file} elfos.h freebsd-spec.h rs6000/sysv4.h"
@@ -2496,10 +2532,14 @@
 	extra_options="${extra_options}"
 	tmake_file="${tmake_file} sparc/t-sparc sparc/t-rtems-64 t-rtems"
 	;;
-sparc64-*-linux*)
+sparc64-*-linux* | sparc64-*-helenos)
 	tm_file="sparc/biarch64.h ${tm_file} dbxelf.h elfos.h sparc/sysv4.h gnu-user.h linux.h glibc-stdint.h sparc/default-64.h sparc/linux64.h sparc/tso.h"
 	extra_options="${extra_options} sparc/long-double-switch.opt"
 	tmake_file="${tmake_file} sparc/t-sparc sparc/t-linux64"
+	# HelenOS
+	case $target in
+	*-helenos*) tm_file="$tm_file sparc/helenos-sparc64.h sparc/helenos64.h" ;;
+	esac
 	;;
 sparc64-*-freebsd*|ultrasparc-*-freebsd*)
 	tm_file="${tm_file} ${fbsd_tm_file} dbxelf.h elfos.h sparc/sysv4.h sparc/freebsd.h"
diff -ud -Nrud gcc-4.8.1/libgcc/config.host gcc-4.8.1/libgcc/config.host
--- gcc-4.8.1/libgcc/config.host	2013-02-04 20:06:20.000000000 +0100
+++ gcc-4.8.1/libgcc/config.host	2013-07-12 09:10:20.120208557 +0200
@@ -195,7 +195,7 @@
       ;;
   esac
   ;;
-*-*-linux* | frv-*-*linux* | *-*-kfreebsd*-gnu | *-*-knetbsd*-gnu | *-*-gnu* | *-*-kopensolaris*-gnu)
+*-*-linux* | frv-*-*linux* | *-*-kfreebsd*-gnu | *-*-knetbsd*-gnu | *-*-gnu* | *-*-kopensolaris*-gnu | *-*-helenos)
   tmake_file="$tmake_file t-crtstuff-pic t-libgcc-pic t-eh-dw2-dip t-slibgcc t-slibgcc-gld t-slibgcc-elf-ver t-linux"
   extra_parts="crtbegin.o crtbeginS.o crtbeginT.o crtend.o crtendS.o"
   ;;
@@ -322,7 +322,7 @@
 arm*-*-netbsdelf*)
 	tmake_file="$tmake_file arm/t-arm arm/t-netbsd t-slibgcc-gld-nover"
 	;;
-arm*-*-linux*)			# ARM GNU/Linux with ELF
+arm*-*-linux* | arm*-helenos-gnueabi)			# ARM GNU/Linux with ELF
 	tmake_file="${tmake_file} arm/t-arm t-fixedpoint-gnu-prefix"
 	tmake_file="${tmake_file} arm/t-elf arm/t-bpabi arm/t-linux-eabi t-slibgcc-libgcc"
 	tm_file="$tm_file arm/bpabi-lib.h"
@@ -518,7 +518,7 @@
 	;;
 x86_64-*-openbsd*)
 	;;
-i[34567]86-*-linux*)
+i[34567]86-*-linux* | i[34567]86-*-helenos)
 	extra_parts="$extra_parts crtprec32.o crtprec64.o crtprec80.o crtfastmath.o"
 	tmake_file="${tmake_file} i386/t-crtpc i386/t-crtfm i386/t-crtstuff t-dfprules"
 	md_unwind_header=i386/linux-unwind.h
@@ -527,7 +527,7 @@
 	extra_parts="$extra_parts crtprec32.o crtprec64.o crtprec80.o crtfastmath.o"
 	tmake_file="${tmake_file} i386/t-crtpc i386/t-crtfm i386/t-crtstuff t-dfprules"
 	;;
-x86_64-*-linux*)
+x86_64-*-linux* | x86_64-*-helenos)
 	extra_parts="$extra_parts crtprec32.o crtprec64.o crtprec80.o crtfastmath.o"
 	tmake_file="${tmake_file} i386/t-crtpc i386/t-crtfm i386/t-crtstuff t-dfprules"
 	md_unwind_header=i386/linux-unwind.h
@@ -631,7 +631,7 @@
 	extra_parts="$extra_parts crtfastmath.o"
 	tmake_file="$tmake_file ia64/t-ia64 ia64/t-ia64-elf ia64/t-eh-ia64 t-crtfm"
 	;;
-ia64*-*-linux*)
+ia64*-*-linux* | ia64-*-helenos)
 	# Don't use crtbeginT.o from *-*-linux* default.
 	extra_parts="crtbegin.o crtend.o crtbeginS.o crtendS.o crtfastmath.o"
 	tmake_file="$tmake_file ia64/t-ia64 ia64/t-ia64-elf t-crtfm t-softfp-tf ia64/t-softfp t-softfp ia64/t-softfp-compat ia64/t-eh-ia64 t-libunwind ia64/t-linux"
@@ -1038,7 +1038,7 @@
 	tmake_file="$tmake_file t-crtfm"
 	extra_parts="$extra_parts crtfastmath.o"
 	;;
-sparc64-*-linux*)		# 64-bit SPARC's running GNU/Linux
+sparc64-*-linux* | sparc64-*-helenos)	# 64-bit SPARC's running GNU/Linux
 	extra_parts="$extra_parts crtfastmath.o"
 	tmake_file="${tmake_file} t-crtfm sparc/t-linux"
 	if test "${host_address}" = 64; then