[llvm] [llvm-debuginfo-analyzer] Fix crash with WebAssembly dead code (PR #141616)

[Carlos Alberto Enciso via llvm-commits]

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@@ -133,6 +133,10 @@ class LVReader {
   // Only for ELF format. The CodeView is handled in a different way.
   LVSectionIndex DotTextSectionIndex = UndefinedSectionIndex;
 
+  // Tombstone value. Assume 64 bits. The value is updated for each
+  // Compile Unit that is processed.
+  LVAddress TombstoneAddress = MaxAddress;
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CarlosAlbertoEnciso wrote:

Checking for a valid (real) tombstone value it is a good idea.
With this patch, we use '-1' for both 32 and 64 bits.

Looking at these DWARF accepted changes:
https://dwarfstd.org/issues/231013.1.html
https://dwarfstd.org/issues/200609.1.html

What would be some `meta-tombstone address` that is not a real one, but that we can identify as `check-marker`? May be the `-2` value? 


https://github.com/llvm/llvm-project/pull/141616