[clang] [Clang] Fix handling of pack indexing types in constraints of redeclaration (PR #139057)

[Younan Zhang via cfe-commits]

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@@ -6884,7 +6884,7 @@ TreeTransform<Derived>::TransformPackIndexingType(TypeLocBuilder &TLB,
     assert(!Unexpanded.empty() && "Pack expansion without parameter packs?");
     // Determine whether the set of unexpanded parameter packs can and should
     // be expanded.
-    bool ShouldExpand = true;
+    bool ShouldExpand = false;
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zyn0217 wrote:

This should be no-op because we always set it to true in CheckParameterPacksForExpansion

https://github.com/llvm/llvm-project/pull/139057