From 5bc805329e558dce02c59a3ac10393432ed8381e Mon Sep 17 00:00:00 2001
From: David Tolnay <dtolnay@gmail.com>
Date: Tue, 13 Mar 2018 09:42:07 -0700
Subject: [PATCH] Drop impl should only panic if not already panicking

---
 serde_derive_internals/src/ctxt.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/serde_derive_internals/src/ctxt.rs b/serde_derive_internals/src/ctxt.rs
index 0ce7916c..454b7c27 100644
--- a/serde_derive_internals/src/ctxt.rs
+++ b/serde_derive_internals/src/ctxt.rs
@@ -8,6 +8,7 @@
 
 use std::fmt::Display;
 use std::cell::RefCell;
+use std::thread;
 
 #[derive(Default)]
 pub struct Ctxt {
@@ -48,7 +49,7 @@ impl Ctxt {
 
 impl Drop for Ctxt {
     fn drop(&mut self) {
-        if self.errors.borrow().is_some() {
+        if !thread::panicking() && self.errors.borrow().is_some() {
             panic!("forgot to check for errors");
         }
     }