From 016eeef04afcdb5665ad7a882d97ee4e01b4ffc4 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 2 Jan 2026 16:40:06 -1000
Subject: [PATCH] [tee501] Use stack-based hex formatting in verbose logging
 (#12795)

---
 esphome/components/tee501/tee501.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/esphome/components/tee501/tee501.cpp b/esphome/components/tee501/tee501.cpp
index d6513dbbe0..06481b628b 100644
--- a/esphome/components/tee501/tee501.cpp
+++ b/esphome/components/tee501/tee501.cpp
@@ -7,6 +7,8 @@ namespace tee501 {
 
 static const char *const TAG = "tee501";
 
+static constexpr size_t TEE501_SERIAL_NUMBER_SIZE = 7;
+
 void TEE501Component::setup() {
   uint8_t address[] = {0x70, 0x29};
   uint8_t identification[9];
@@ -17,7 +19,10 @@ void TEE501Component::setup() {
     this->mark_failed();
     return;
   }
-  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex(identification + 0, 7).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char serial_hex[format_hex_size(TEE501_SERIAL_NUMBER_SIZE)];
+#endif
+  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex_to(serial_hex, identification, TEE501_SERIAL_NUMBER_SIZE));
 }
 
 void TEE501Component::dump_config() {