[clang] [Clang][Modules] Fix crash when redefining default template argument (PR #185237)

[Chuanqi Xu via cfe-commits]

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@@ -8138,9 +8167,6 @@ static Expr *BuildExpressionFromNonTypeTemplateArgumentValue(
     return MakeInitList(Elts);
   }
 
-  case APValue::Matrix:
-    llvm_unreachable("Matrix template argument expression not yet supported");
-
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ChuanqiXu9 wrote:

Why? The change seems not related?

https://github.com/llvm/llvm-project/pull/185237