[llvm] [LTO] Introduce a helper lambda in gatherImportedSummariesForModule (NFC) (PR #106251)

[Teresa Johnson via llvm-commits]

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@@ -1293,7 +1293,8 @@ using GVSummaryMapTy = DenseMap<GlobalValue::GUID, GlobalValueSummary *>;
 
 /// Map of a module name to the GUIDs and summaries we will import from that
 /// module.
-using ModuleToSummariesForIndexTy = std::map<std::string, GVSummaryMapTy>;
+using ModuleToSummariesForIndexTy =
+    std::map<std::string, GVSummaryMapTy, std::less<>>;
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teresajohnson wrote:

Is this change needed, since std::less is the default?

https://github.com/llvm/llvm-project/pull/106251