From 8742762dd8af0743ca0618b4070dcce7cc183548 Mon Sep 17 00:00:00 2001
From: Jules Bertholet <jules@bertholet.email>
Date: Thu, 5 Nov 2026 14:50:22 -0500
Subject: [PATCH 1/3] blobby: don't PlaceMention an uninitialized local in
 `parse_into_structs`

Our MSRV is too old for `cfg(false)`, so we use `cfg(any())` instead.
---
 blobby/src/decode.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/blobby/src/decode.rs b/blobby/src/decode.rs
index 8331746f..4c866625 100644
--- a/blobby/src/decode.rs
+++ b/blobby/src/decode.rs
@@ -254,7 +254,7 @@ macro_rules! parse_into_structs {
             }
 
             const ITEM_FIELDS: usize = 0 $( + {
-                let $field: (); let _ = $field;
+                #[cfg(any())] { $field }
                 1
             })*;
 

From eff10f17440c3564f81dabc17d9a06e4605ac711 Mon Sep 17 00:00:00 2001
From: Artyom Pavlov <newpavlov@gmail.com>
Date: Sat, 7 Nov 2026 13:46:10 +0300
Subject: [PATCH 2/3] tweak

---
 blobby/src/decode.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/blobby/src/decode.rs b/blobby/src/decode.rs
index 4c866625..66c2b123 100644
--- a/blobby/src/decode.rs
+++ b/blobby/src/decode.rs
@@ -253,8 +253,11 @@ macro_rules! parse_into_structs {
                 }
             }
 
+            // TODO: use `${count(field)}` on stabilization of `macro_metavar_expr`:
+            // https://github.com/rust-lang/rust/issues/83527
             const ITEM_FIELDS: usize = 0 $( + {
-                #[cfg(any())] { $field }
+                let $field = ();
+                let _ = $field;
                 1
             })*;
 

From 252572e1b467a0600a5e7184c58cf3d45b8fbaee Mon Sep 17 00:00:00 2001
From: Artyom Pavlov <newpavlov@gmail.com>
Date: Sat, 7 Nov 2026 13:48:22 +0300
Subject: [PATCH 3/3] Add changelog entry

---
 blobby/CHANGELOG.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/blobby/CHANGELOG.md b/blobby/CHANGELOG.md
index b7bcfce8..6fcb6df0 100644
--- a/blobby/CHANGELOG.md
+++ b/blobby/CHANGELOG.md
@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 0.4.1 (UNRELEASED)
+### Changed
+- Don't `PlaceMention` an uninitialized local in `parse_into_structs` ([#1588])
+
+[#1588]: https://github.com/RustCrypto/utils/pull/1588
+
 ## 0.4.0 (2025-10-08)
 ### Changed
 - Edition changed to 2024 and MSRV bumped to 1.85 ([#1149])