[clang] [Clang] Complete the element type when list-initializing an array of unknown bound (PR #221488)

[Shengxin Pei via cfe-commits]

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@@ -641,6 +641,10 @@ features cannot lower the translation-unit ABI level;
   (#GH214128)
 - Fixed a crash when a coroutine keyword appeared inside a mem-initializer on a
   function that is not a constructor. (#GH194298)
+- Fixed a crash when list-initializing an array of unknown bound from an empty
+  initializer list whose element type is an uninstantiated class template
+  specialization or an incomplete class; the element type is now completed
+  first. (#GH217883)
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TPPPP72 wrote:

```suggestion
  specialization or an incomplete class. (#GH217883)
```

https://github.com/llvm/llvm-project/pull/221488