[clang] [Clang] Fix various bugs in alias CTAD transform (PR #132061)

[via cfe-commits]

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@@ -3660,6 +3660,8 @@ class TreeTransform {
     return SemaRef.BuildCXXNoexceptExpr(Range.getBegin(), Arg, Range.getEnd());
   }
 
+  bool HeuristicallyComputeSizeOfPackExpr() const { return true; }
+
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cor3ntin wrote:

I think I would prefer to add a `TransformSizeOfPackExpr` override in TemplateInstantiator that calls
back to the base implementation with a bool parameter, or something like that


https://github.com/llvm/llvm-project/pull/132061