[clang] [OpenACC] Implement 'default' clause parsing. (PR #77002)

[Alexey Bataev via cfe-commits]

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@@ -90,9 +90,21 @@ enum class OpenACCClauseKind {
   Vector,
   // 'nohost' clause, allowed on 'routine' directives.
   NoHost,
+  // 'default' clause, allowed on parallel, serial, kernel (and compound)
+  // constructs.
+  Default,
   // Represents an invalid clause, for the purposes of parsing.
   Invalid,
 };
+
+enum class OpenACCDefaultClauseKind {
+  // 'none' option.
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alexey-bataev wrote:

Use `///` style here

https://github.com/llvm/llvm-project/pull/77002