[clang] [Clang] [C++26] Implement P1306R5 Expansion Statements (PR #165195)

[Erich Keane via cfe-commits]

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@@ -524,6 +525,354 @@ class CoreturnStmt : public Stmt {
   }
 };
 
+/// CXXExpansionStmt - Base class for an unexpanded C++ expansion statement.
+class CXXExpansionStmt : public Stmt {
+  friend class ASTStmtReader;
+
+  ExpansionStmtDecl *ParentDecl;
+  SourceLocation ForLoc;
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erichkeane wrote:

When is this not just `BeginLoc`? 

https://github.com/llvm/llvm-project/pull/165195