diff -Nrup a/src/ui_basic/box.cc b/src/ui_basic/box.cc
--- a/src/ui_basic/box.cc	2019-05-01 23:23:39.000000000 -0600
+++ b/src/ui_basic/box.cc	2019-11-12 16:10:28.893117299 -0700
@@ -104,7 +104,7 @@ void Box::update_desired_size() {
 	int maxbreadth = mindesiredbreadth_;
 
 	for (uint32_t idx = 0; idx < items_.size(); ++idx) {
-		int depth, breadth = 0;
+		int depth = 0, breadth = 0;
 		get_item_desired_size(idx, &depth, &breadth);
 
 		totaldepth += depth;