[clang] [clang-tools-extra] [Attributes][HLSL] Teach EnumArgument to refer to an external enum (PR #70835)

[Erich Keane via cfe-commits]

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@@ -1015,7 +1018,8 @@ def ExternalSourceSymbol : InheritableAttr {
 
 def Blocks : InheritableAttr {
   let Spellings = [Clang<"blocks">];
-  let Args = [EnumArgument<"Type", "BlockType", ["byref"], ["ByRef"]>];
+  let Args = [EnumArgument<"Type", "BlockType",
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erichkeane wrote:

The two changes here that are just formatting can now be reverted.

https://github.com/llvm/llvm-project/pull/70835