[llvm] [ADT] Series of improvements to SmallSet (PR #104611)

[Sergei Barannikov via llvm-commits]

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@@ -14,14 +14,13 @@
 #ifndef LLVM_ADT_SMALLSET_H
 #define LLVM_ADT_SMALLSET_H
 
+#include "llvm/ADT/STLExtras.h"
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s-barannikov wrote:

I understand that this include existed before this patch, but can it be avoided?
Even DenseMap.h doesn't include it.


https://github.com/llvm/llvm-project/pull/104611