From a7bbfa2a649ae2896a95d42f875637055c24b28a Mon Sep 17 00:00:00 2001
From: Robert Ekl <ekl.rob@gmail.com>
Date: Tue, 24 Feb 2026 00:16:02 -0600
Subject: [PATCH] fix(txtdata): avoid UB in _ftoa bit shifts

Use unsigned intermediate shifts when deriving integer and fractional parts to avoid signed left-shift undefined behavior under UBSAN.

Keeps formatting behavior intact while making sanitizer runs pass.
---
 src/helpers/TxtDataHelpers.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/helpers/TxtDataHelpers.cpp b/src/helpers/TxtDataHelpers.cpp
index d327931fd..0cebcc021 100644
--- a/src/helpers/TxtDataHelpers.cpp
+++ b/src/helpers/TxtDataHelpers.cpp
@@ -83,12 +83,12 @@ static void _ftoa(float f, char *p, int *status)
   } 
   else if (exp2 >= 23)
   { 
-    int_part = mantissa<<(exp2 - 23);
+    int_part = static_cast<int32_t>(static_cast<uint32_t>(mantissa) << (exp2 - 23));
   }
   else if (exp2 >= 0) 
   {
     int_part = mantissa>>(23 - exp2);
-    frac_part = (mantissa<<(exp2 + 1))&0xFFFFFF;
+    frac_part = static_cast<int32_t>((static_cast<uint32_t>(mantissa) << (exp2 + 1)) & 0xFFFFFFu);
   } 
   else 
   {