From c9149310778ac85ae85a985cc59f5077236fbddc Mon Sep 17 00:00:00 2001
From: Kyle Huey <khuey@kylehuey.com>
Date: Tue, 23 Sep 2025 20:29:37 -0700
Subject: [PATCH] Upgrade `cpp_demangle` to the latest version.

cpp_demangle 0.5.0 drops the `Display` impl on the `Symbol` object because it can
subtly violate the `Display` contract. The recommended replacement is
`Symbol::demangle`.

Changelog: https://github.com/gimli-rs/cpp_demangle/blob/0.5.0/CHANGELOG.md#050
---
 Cargo.lock           |  4 ++--
 Cargo.toml           |  2 +-
 src/symbolize/mod.rs | 14 ++++++++------
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 2730a4b1..1312460b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -66,9 +66,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "cpp_demangle"
-version = "0.4.4"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96e58d342ad113c2b878f16d5d034c03be492ae460cdbc02b7f0f2284d310c7d"
+checksum = "4dcc405d55da54ad965aff198909afdcc8aeefc8ac6ba26d6abd19aa8aeacb2a"
 dependencies = [
  "cfg-if",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index 7e1233c9..c0f6f8be 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,7 +34,7 @@ rustc-demangle = "0.1.24"
 serde = { version = "1.0", optional = true, features = ['derive'] }
 
 # Optionally demangle C++ frames' symbols in backtraces.
-cpp_demangle = { default-features = false, version = "0.4.0", optional = true, features = [
+cpp_demangle = { default-features = false, version = "0.5.0", optional = true, features = [
   "alloc",
 ] }
 
diff --git a/src/symbolize/mod.rs b/src/symbolize/mod.rs
index 137d2ea3..62714f04 100644
--- a/src/symbolize/mod.rs
+++ b/src/symbolize/mod.rs
@@ -373,8 +373,13 @@ impl<'a> fmt::Display for SymbolName<'a> {
 
         #[cfg(feature = "cpp_demangle")]
         {
+            // This may fail to print if the demangled symbol isn't actually
+            // valid, so handle the error here gracefully by not propagating
+            // it outwards.
             if let Some(ref cpp) = self.cpp_demangled.0 {
-                return cpp.fmt(f);
+                if let Ok(s) = cpp.demangle() {
+                    return s.fmt(f);
+                }
             }
         }
 
@@ -390,14 +395,11 @@ impl<'a> fmt::Debug for SymbolName<'a> {
 
         #[cfg(all(feature = "std", feature = "cpp_demangle"))]
         {
-            use std::fmt::Write;
-
-            // This may to print if the demangled symbol isn't actually
+            // This may fail to print if the demangled symbol isn't actually
             // valid, so handle the error here gracefully by not propagating
             // it outwards.
             if let Some(ref cpp) = self.cpp_demangled.0 {
-                let mut s = String::new();
-                if write!(s, "{cpp}").is_ok() {
+                if let Ok(s) = cpp.demangle() {
                     return s.fmt(f);
                 }
             }