[lld] [WebAssembly] Fix issues combining coop threads and PIC (PR #208332)

[Sam Clegg via llvm-commits]

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@@ -1152,6 +1161,10 @@ void Writer::combineOutputSegments() {
   }
 
   segments = std::move(newSegments);
+
+  // Fixup indices for any segments that have moved around.
+  for (size_t i = 0; i < segments.size(); ++i)
+    segments[i]->index = i;
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sbc100 wrote:

Why is this needed as part of this change (but not before)?

https://github.com/llvm/llvm-project/pull/208332