diff --git a/scripts/rbc-run b/scripts/rbc-run
index 235da75..7243421 100755
--- a/scripts/rbc-run
+++ b/scripts/rbc-run
@@ -2,7 +2,7 @@
 # Convert and run one configuration
 # Args: a product/board makefile optionally followed by additional arguments
 #       that will be passed to rbcrun.
-[[ $# -gt 0 && -f "$1" ]] || { echo "Usage: ${0##*/} product.mk [Additional rbcrun arguments]" >&2; exit 1; }
+[[ $# -gt 1 && -f "$1" && -f "$2" ]] || { echo "Usage: ${0##*/} product.mk input_variables.mk [Additional rbcrun arguments]" >&2; exit 1; }
 set -eu
 
 declare -r output_root="${OUT_DIR:-out}"
@@ -10,7 +10,8 @@
 declare -r converter="${output_root}/soong/mk2rbc"
 declare -r launcher="${output_root}/rbc/launcher.rbc"
 declare -r makefile="$1"
-shift
-"${converter}" -mode=write -r --outdir "${output_root}/rbc" --launcher="${launcher}" "${makefile}"
+declare -r input_variables="$2"
+shift 2
+"${converter}" -mode=write -r --outdir "${output_root}/rbc" --input_variables "${input_variables}" --launcher="${launcher}" "${makefile}"
 "${runner}" RBC_OUT="make,global" RBC_DEBUG="${RBC_DEBUG:-}" $@ "${launcher}"