[clang-tools-extra] [llvm] [LLVM][Support] Move default values out of the storage (PR #184581)

[Steffen Larsen via llvm-commits]

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@@ -1722,6 +1722,11 @@ class list : public Option, public list_storage<DataType, StorageClass> {
     Parser.initialize();
   }
 
+protected:
+  bool isDefaultAssigned() const { return DefaultAssigned; }
+  void overwriteDefault() { DefaultAssigned = false; }
+  ArrayRef<OptionValue<DataType>> getDefault() const { return Default; }
+
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steffenlarsen wrote:

Personally I am not much for it either, but they were previously defined in `opt_storage` and are used in MLIR's `PassOptions.h` through inheritance. Another option is to make the "Default" members protected. I'm fine with either, but I've added a comment for the current solution if that's the one we want to roll with.

https://github.com/llvm/llvm-project/pull/184581