diff --git a/configure.ac b/configure.ac
index fb40c6ed..1267f6f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -85,6 +85,7 @@ if command -v "$GRADLE" >/dev/null; then
     AC_MSG_RESULT([$GRADLE])
     AM_CONDITIONAL(HAVE_GRADLE, [test 1 = 1])
 else
+    GRADLE=
     AC_MSG_RESULT([no])
     AM_CONDITIONAL(HAVE_GRADLE, [test 1 = 0])
 fi