Avoid repopulating dead nodes; otherwise, we might wind up killing a node multiple times, screwing up the free list of available closure IDs (with duplicates), so that the same ID gets allocated for multiple functions later

1 files changed, 2 insertions, 0 deletions

diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index 68e7979d..b871b8e5 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -731,6 +731,8 @@ function flattenLocal(s) {
 // Dynamic tree management
 
 function populate(node) {
+    if (node.dead) return;
+
     var s = node.signal;
     var oldSources = node.sources;
     try {