gcc: update to 4.6.3. Build multilib pkgs on x86_64.

srcpkgs/gcc/gcc-c++-multilib.template

@@ -0,0 +1,22 @@
+# Template file for 'gcc-c++-multilib'.
+#
+short_desc="GCC C++ compiler (multilib files)"
+long_desc="
+ This is the GNU C++ compiler, a fairly portable optimizing compiler for C++.
+
+ On architectures with multilib support, the package contains files and
+ dependencies for the non-default multilib architecture(s)."
+
+noverifyrdeps=yes
+
+Add_dependency run gcc-c++		">=${version}"
+Add_dependency run gcc-multilib		">=${version}"
+Add_dependency run libstdc++32-devel	">=${version}"
+
+do_install() {
+	local libmddir="usr/lib/gcc/${_triplet}/${_majorver}"
+
+	for f in std sup; do
+		vmove usr/lib32/lib${f}c++.a ${libmddir}/32
+	done
+}