diff -rup a/expr.c b/expr.c
--- a/expr.c 2013-10-10 08:43:55.000000000 -0400
+++ b/expr.c 2020-02-06 17:05:40.658679755 -0500
@@ -189,10 +189,10 @@ int
expr_clone(struct expr_node *retp, const struct expr_node *node)
{
*retp = *node;
+ struct expr_node *nlhs;
+ struct expr_node *nrhs = NULL;
switch (node->kind) {
- struct expr_node *nlhs;
- struct expr_node *nrhs;
case EXPR_OP_ARGNO:
case EXPR_OP_SELF: