[clang] [Clang][Sema] Fix crash on init-list of array with incomplete element type (PR #205973)

[Corentin Jabot via cfe-commits]

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@@ -816,6 +816,7 @@ Bug Fixes to C++ Support
 - Fixed an issue where Clang incorrectly accepted invalid unqualified uses of local nested class names outside their declaring scope. (#GH184622)
 - Fixed a crash when parsing invalid friend declaration with storage-class specifier. (#GH186569)
 - Fixed a missing vtable for ``dynamic_cast<FinalClass *>(this)`` in a function template. (#GH198511)
+- Fixed an assertion failure during init-list checking of an array whose element type is an incomplete (forward-declared) class. (#GH140685)
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cor3ntin wrote:

```suggestion
- Fixed an assertion failure during init-list checking of an array whose element type is an incomplete class. (#GH140685)
```

https://github.com/llvm/llvm-project/pull/205973