[clang] [clang-tools-extra] [lld] [llvm] [llvm] Add subcommand support for OptTable (PR #155026)

[via llvm-commits]

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@@ -10,6 +10,7 @@
 #define LLVM_OPTION_OPTTABLE_H
 
 #include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/SmallSet.h"
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PiJoules wrote:

smallset seems unused here?

https://github.com/llvm/llvm-project/pull/155026