https://github.com/yingcong-wu created 
https://github.com/llvm/llvm-project/pull/154902

There is an off-by-one error with current condition check for PC fallen into 
the range or not. There is another check within libunwind that use the correct 
checks in 
https://github.com/llvm/llvm-project/blob/5050da7ba18fc876f80fbeaaca3564d3b4483bb8/libunwind/src/UnwindCursor.hpp#L2757
```
      if ((fdeInfo.pcStart <= pc) && (pc < fdeInfo.pcEnd))
```

>From 57ebc553828bf696b4bde30789e609ba96e94d6d Mon Sep 17 00:00:00 2001
From: Wu Yingcong <yingcong...@intel.com>
Date: Fri, 22 Aug 2025 15:16:47 +0800
Subject: [PATCH] fix missing by one bug

---
 libunwind/src/DwarfParser.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libunwind/src/DwarfParser.hpp b/libunwind/src/DwarfParser.hpp
index 7e85025dd054d..25250e0810987 100644
--- a/libunwind/src/DwarfParser.hpp
+++ b/libunwind/src/DwarfParser.hpp
@@ -273,7 +273,7 @@ bool CFI_Parser<A>::findFDE(A &addressSpace, pint_t pc, 
pint_t ehSectionStart,
           pint_t pcRange = addressSpace.getEncodedP(
               p, nextCFI, cieInfo->pointerEncoding & 0x0F);
           // Test if pc is within the function this FDE covers.
-          if ((pcStart < pc) && (pc <= pcStart + pcRange)) {
+          if ((pcStart <= pc) && (pc < pcStart + pcRange)) {
             // parse rest of info
             fdeInfo->lsda = 0;
             // check for augmentation length

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