diff --git a/oem/firstvoices/common/build_keyboards.sh b/oem/firstvoices/common/build_keyboards.sh
index ec4ace8819..7ead3ceb73 100755
--- a/oem/firstvoices/common/build_keyboards.sh
+++ b/oem/firstvoices/common/build_keyboards.sh
@@ -84,7 +84,7 @@ while [[ $# -gt 0 ]] ; do
 done
 
 # Check that $KEYBOARDS_TARGET is valid
-if [[ $KEYBOARDS_TARGET == "" ]]; then
+if [[ -z "$KEYBOARDS_TARGET" ]]; then
   die "KEYBOARDS_TARGET cannot be empty"
 fi