[clang] [clang-tools-extra] [clang] Make `InitListExpr::isExplicit()` work (PR #195175)

[Andrey Ali Khan Bolshakov via cfe-commits]

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@@ -649,8 +649,8 @@ BuiltinTypeMethodBuilder &BuiltinTypeMethodBuilder::concat(V Vec, S Scalar,
   }
   Elts.push_back(ScalarExpr);
 
-  auto *InitList =
-      new (AST) InitListExpr(AST, SourceLocation(), Elts, SourceLocation());
+  auto *InitList = new (AST) InitListExpr(
+      AST, SourceLocation(), Elts, SourceLocation(), /*isExplicit=*/false);
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bolshakov-a wrote:

I guess this initializer list should be marked as implicit because it is inside a builtin HLSL declaration. CC @s-perron

https://github.com/llvm/llvm-project/pull/195175