[llvm] [DWARFLinker] Adjust DW_AT_LLVM_stmt_sequence for rewritten line tables (PR #128953)

[Jonas Devlieghere via llvm-commits]

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@@ -1447,6 +1447,18 @@ unsigned DWARFLinker::DIECloner::cloneScalarAttribute(
         ->sizeOf(Unit.getOrigUnit().getFormParams());
   }
 
+  if (AttrSpec.Attr == dwarf::DW_AT_LLVM_stmt_sequence) {
+    // If needed, we'll patch this sec_offset later with the correct offset.
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JDevlieghere wrote:

Just to make sure I understand: The only time this won't get patched is when you're doing an update, otherwise we'll always correct the offset. And to avoid having to do all this work in the update case, you're not setting it to the 'invalid offset' magic value here. 

https://github.com/llvm/llvm-project/pull/128953