From f4c4af2bd485b88b7928d9a0ac35a06db2907e70 Mon Sep 17 00:00:00 2001
From: Anthony Ramine <nox@nox.paris>
Date: Fri, 15 May 2020 12:12:37 +0200
Subject: [PATCH] Don't panic while already panicking in BoxSlot::drop

---
 components/layout_2020/dom_traversal.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/components/layout_2020/dom_traversal.rs b/components/layout_2020/dom_traversal.rs
index a8f5a17fc1d..c043d3b75d3 100644
--- a/components/layout_2020/dom_traversal.rs
+++ b/components/layout_2020/dom_traversal.rs
@@ -346,8 +346,10 @@ impl BoxSlot<'_> {
 
 impl Drop for BoxSlot<'_> {
     fn drop(&mut self) {
-        if let Some(slot) = &mut self.slot {
-            assert!(slot.borrow().is_some(), "failed to set a layout box");
+        if !std::thread::panicking() {
+            if let Some(slot) = &mut self.slot {
+                assert!(slot.borrow().is_some(), "failed to set a layout box");
+            }
         }
     }
 }