[clang] [Clang] Add BuiltinTemplates.td to generate code for builtin templates (PR #123736)

[Erich Keane via cfe-commits]

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@@ -624,9 +621,9 @@ class ASTContext : public RefCountedBase<ASTContext> {
 
   TranslationUnitDecl *TUDecl = nullptr;
   mutable ExternCContextDecl *ExternCContext = nullptr;
-  mutable BuiltinTemplateDecl *MakeIntegerSeqDecl = nullptr;
-  mutable BuiltinTemplateDecl *TypePackElementDecl = nullptr;
-  mutable BuiltinTemplateDecl *BuiltinCommonTypeDecl = nullptr;
+
+#define BuiltinTemplate(Name) mutable BuiltinTemplateDecl *Decl##Name = nullptr;
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erichkeane wrote:

Can we be consistent on the uses with the argument name?  Seems split between `Name` and `BTName`.

https://github.com/llvm/llvm-project/pull/123736