gistfile1.txt

commit af86cf932c9cd76eeaf404896e1603a58d442a56
Author: Yoshi Cheng-Hao Huang <allstars.chh@gmail.com>
Date:   Fri Oct 18 13:40:39 2019 +0200

    Bug 1576592 - bail out if atom is nullptr.

diff --git a/js/src/vm/JSAtom.cpp b/js/src/vm/JSAtom.cpp
index 9b813f48f39d..07eb473376b0 100644
--- a/js/src/vm/JSAtom.cpp
+++ b/js/src/vm/JSAtom.cpp
@@ -596,16 +596,23 @@ bool AtomsTable::sweepIncrementally(SweepIterator& atomsToSweep,
   while (!atomsToSweep.empty()) {
     budget.step();
     if (budget.isOverBudget()) {
       return false;
     }
 
     JSAtom* atom = atomsToSweep.front();
     MOZ_DIAGNOSTIC_ASSERT(atom);
+    // TODO: Bug XXX
+    // skip in opt build.
+    if (!atom) {
+      atomsToSweep.removeFront();
+      continue;
+    }
+
     // TODO: Bug 1574981 - investigate talos regression in
     // AtomsTable::sweepIncrementally
     if (IsAboutToBeFinalizedUnbarriered(&atom)) {
       MOZ_ASSERT(!atom->isPinned());
       atomsToSweep.removeFront();
     } else {
       MOZ_ASSERT(atom == atomsToSweep.front());
     }