[Mlir-commits] [llvm] [mlir] [ADT] Use a dedicated empty type for StringSet (NFC) (PR #165967)

[Matt Arsenault]

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@@ -382,7 +382,7 @@ std::error_code YAMLProfileWriter::writeProfile(const RewriteInstance &RI) {
   StringSet<> EventNames = RI.getProfileReader()->getEventNames();
   if (!EventNames.empty()) {
     std::string Sep;
-    for (const StringMapEntry<std::nullopt_t> &EventEntry : EventNames) {
+    for (const auto &EventEntry : EventNames) {
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arsenm wrote:

no auto? 

https://github.com/llvm/llvm-project/pull/165967