cross-aarch64-linux-gnu: unrestrict to all 64-bit glibc

srcpkgs/cross-aarch64-linux-gnu/template

@@ -35,7 +35,18 @@ makedepends="isl15-devel libmpc-devel zlib-devel"
 depends="${pkgname}-libc-${version}_${revision}"
 nostrip_files="libcaf_single.a libgcc.a libgcov.a libgcc_eh.a
  libgnarl_pic.a libgnarl.a libgnat_pic.a libgnat.a"
-archs="x86_64 ppc64le"
+
+if [ "$XBPS_TARGET_LIBC" != "glibc" ]; then
+	broken="glibc crosstoolchain only available on glibc"
+fi
+
+if [ "$XBPS_TARGET_WORDSIZE" != "64" ]; then
+	broken="64-bit crosstoolchain only available on 64-bit host"
+fi
+
+if [ "$XBPS_TARGET_MACHINE" = "aarch64" ]; then
+	broken="Can't build crosstoolchain to itself"
+fi
 
 _apply_patch() {
 	local args="$1" pname="$(basename $2)"