[clang] [Clang] Implement P2747 constexpr placement new (PR #104586)

[Aaron Ballman via cfe-commits]

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@@ -6691,7 +6691,7 @@ static bool HandleDestructionImpl(EvalInfo &Info, SourceRange CallRange,
     if (Size && Size > Value.getArrayInitializedElts())
       expandArray(Value, Value.getArraySize() - 1);
 
-    for (; Size != 0; --Size) {
+    for (Size = Value.getArraySize(); Size != 0; --Size) {
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AaronBallman wrote:

It'd be good to have a comment here explaining that.

https://github.com/llvm/llvm-project/pull/104586