[clang] [OpenACC] Implement Sema work for OpenACC Clauses (PR #87821)

[Erich Keane via cfe-commits]

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@@ -82,22 +119,22 @@ bool SemaOpenACC::ActOnStartStmtDirective(OpenACCDirectiveKind K,
   return diagnoseConstructAppertainment(*this, K, StartLoc, /*IsStmt=*/true);
 }
 
-StmtResult SemaOpenACC::ActOnEndStmtDirective(OpenACCDirectiveKind K,
-                                              SourceLocation StartLoc,
-                                              SourceLocation EndLoc,
-                                              StmtResult AssocStmt) {
+StmtResult SemaOpenACC::ActOnEndStmtDirective(
+    OpenACCDirectiveKind K, SourceLocation StartLoc, SourceLocation EndLoc,
+    MutableArrayRef<OpenACCClause *> Clauses, StmtResult AssocStmt) {
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erichkeane wrote:

It doesn't seem that `OwningArrayRef` is what I want, is it?   That is an array-ref that copies the elements into a newly allocated 'thing'.  My thought is that we want the call to `ActOnEndStmtDirective` to 'take' ownership of an existing allocation.

A part of me thinks I should perhaps be storing these as a `SmallVector<unique_ptr<OpenACCClause>>` instead, then taking that by value here, so it is clear that it 'owns' it.

https://github.com/llvm/llvm-project/pull/87821