[llvm] Use MapVector to fix lld thinLTO bep issue. (PR #117551)

[via llvm-commits]

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@@ -28,11 +29,11 @@ class RecordStreamer : public MCStreamer {
 
 private:
   const Module &M;
-  StringMap<State> Symbols;
+  MapVector<StringRef, State> Symbols;
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llvmssh wrote:

Symbols generation order comes from traversing SymverAliasMap in flushSymverDirectives func, which is an unordered map data structure, and I understand that traversing creates nondeterminism problems.

https://github.com/llvm/llvm-project/pull/117551