diff --git a/configure.ac b/configure.ac
index c5cf3b0d..95ce0f0f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -126,6 +126,9 @@ if test "x$opencl" != xno; then
 	found_opencl=0])
 	LIBS=$SAVED_LIBS
 	CFLAGS=$SAVED_CFLAGS
+else
+	OPENCL_FLAGS=""
+	OPENCL_LIBS=""
 fi
 
 AC_CHECK_LIB(pthread, pthread_create, ,