[clang] Reapply "[Clang][Sema] placement new initializes typedef array with correct size (#83124)" (PR #89036)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,23 @@
+// RUN: %clang --target=x86_64-pc-linux -S -fno-discard-value-names -emit-llvm -o - %s | FileCheck %s
+
+namespace std {
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erichkeane wrote:

Tests STILL haven't changed from the original patch.  Please add the regression to this test as well.

https://github.com/llvm/llvm-project/pull/89036