[clang] [clang] Fix crash constant-evaluating the construction of huge arrays (PR #226899)

[Shafik Yaghmour via cfe-commits]

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@@ -3033,6 +3042,8 @@ bool Compiler<Emitter>::VisitArrayInitLoopExpr(const ArrayInitLoopExpr *E) {
   const Expr *SubExpr = E->getSubExpr();
   OptPrimType SubExprT = classify(SubExpr);
   size_t Size = E->getArraySize().getZExtValue();
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shafik wrote:

So we are not being consistent here. We use `uint64_t` below but `size_t` here and we should not be using these interchangeably. I believe we should be using `uint64_t` here.

@tbaederr we are a bit sloppy in this function we are implicitly converting a `size_t` to `uint32_t` in a couple of cases below and we should be more explicit about that.

https://github.com/llvm/llvm-project/pull/226899