support gcc-4.7+ multilib list with x86_64 targets

diff --git a/eclass/toolchain.eclass b/eclass/toolchain.eclass
index d003b876b6d7bdd2f2255f49a24fce9c11f37ae0..f3df4da9fc21bd8eddb950a0f9b4e5e97c94ce42 100644 (file)
--- a/eclass/toolchain.eclass
+++ b/eclass/toolchain.eclass
@@ -1,6 +1,6 @@
 # Copyright 1999-2008 Gentoo Foundation
 # Distributed under the terms of the GNU General Public License v2
-# $Header: /var/cvsroot/gentoo-x86/eclass/toolchain.eclass,v 1.467 2011/09/12 05:40:23 vapier Exp $
+# $Header: /var/cvsroot/gentoo-x86/eclass/toolchain.eclass,v 1.468 2011/09/13 16:30:00 vapier Exp $
 #
 # Maintainer: Toolchain Ninjas <toolchain@gentoo.org>
 
@@ -1091,20 +1091,37 @@ gcc_src_unpack() {
        disable_multilib_libjava || die "failed to disable multilib java"
 }
 
-gcc-library-configure() {
-       if is_multilib ; then
-               confgcc+=" --enable-multilib"
-       else
+gcc-multilib-configure() {
+       # if multilib is disabled, get out quick!
+       if ! is_multilib ; then
                confgcc+=" --disable-multilib"
+               return
+       else
+               confgcc+=" --enable-multilib"
        fi
+
+       # translate our notion of multilibs into gcc's
+       local abi map=() list
+       case ${CTARGET} in
+       x86_64*) tc_version_is_at_least 4.7 && map=(amd64:m64 x86:m32 x32:mx32) ;;
+       esac
+       for abi in $(get_all_abis) ; do
+               local m a l
+               for m in "${map[@]}" ; do
+                       a=${m%:*}
+                       l=${m#*:}
+                       [[ ${abi} == ${a} ]] && list=",${l}${list}"
+               done
+       done
+       [[ -n ${list} ]] && confgcc+=" --with-multilib-list=${list:1}"
+}
+
+gcc-library-configure() {
+       gcc-multilib-configure
 }
 
 gcc-compiler-configure() {
-       if is_multilib ; then
-               confgcc+=" --enable-multilib"
-       else
-               confgcc+=" --disable-multilib"
-       fi
+       gcc-multilib-configure
 
        if tc_version_is_at_least "4.0" ; then
                if has mudflap ${IUSE} ; then