diff --git a/build_library/toolchain_util.sh b/build_library/toolchain_util.sh
index 69a7d46a0c..5ab2c6e470 100644
--- a/build_library/toolchain_util.sh
+++ b/build_library/toolchain_util.sh
@@ -43,6 +43,7 @@ declare -r \
 # Usage: get_portage_arch chost
 get_portage_arch() {
     case "$1" in
+        aarch64*)   echo arm64;;
         alpha*)     echo alpha;;
         arm*)       echo arm;;
         hppa*)      echo hppa;;