commit 511b3aa71fae5d4e941fe3159828c84c7f74ba51
from: Omar Polo <op@omarpolo.com>
date: Sat Aug 07 09:37:56 2021 UTC

guard against assigning variables to void values

commit - c4d04e1c300d4ff855a18779e7de362a7987c46d
commit + 511b3aa71fae5d4e941fe3159828c84c7f74ba51
blob - cb8c623fc00b991d06136a34833c8c3ade724e71
blob + 8e604fe1fe17883283a912f4595e5c31887f54a6
--- script.c
+++ script.c
@@ -236,11 +236,20 @@ setvar(char *sym, struct op *op)
 {
 	struct binding	*b;
 	struct env	*e;
-	int		 ret;
+	int		 ret, height;
 
+	height = stackh;
 	if ((ret = eval(op)) != EVAL_OK)
 		return ret;
 
+	if (stackh != height + 1) {
+		before_printing();
+		printf("trying to assign to `%s' a void value: ", sym);
+		pp_op(op);
+		printf("\n");
+		return EVAL_ERR;
+	}
+
 	b = xcalloc(1, sizeof(*b));
 	b->name = sym;
 	popv(&b->val);