From 9b83f37b786b7136516c4df80bd9d0e7ee28167d Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Sun, 4 Oct 2026 18:02:27 -0500
Subject: [PATCH] [core] Let the empty Scheduler mutex take no space on
 single-threaded platforms (#20139)

---
 esphome/core/scheduler.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/esphome/core/scheduler.h b/esphome/core/scheduler.h
index 56fc83f12f..4911bdde74 100644
--- a/esphome/core/scheduler.h
+++ b/esphome/core/scheduler.h
@@ -518,7 +518,8 @@ class Scheduler {
                                                                             uint32_t hash_or_id,
                                                                             SchedulerItem::Type type, bool find_first);
 
-  Mutex lock_;
+  // Empty on single-threaded platforms (ESP8266, RP2), so it takes no space there
+  [[no_unique_address]] Mutex lock_;
   std::vector<SchedulerItem *> items_;
   std::vector<SchedulerItem *> to_add_;