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

[Erich Keane via cfe-commits]

================
@@ -12864,6 +12864,19 @@ TreeTransform<Derived>::TransformCXXNewExpr(CXXNewExpr *E) {
     ArraySize = NewArraySize.get();
   }
 
+  // Per C++0x [expr.new]p5, the type being constructed may be a
+  // typedef of an array type.
+  QualType AllocType = AllocTypeInfo->getType();
+  if (ArraySize && E->isTypeDependent()) {
----------------
erichkeane wrote:

Note I asked about VALUE dependence, not TYPE dependence.  I see why type dependence would matter, but expressions can be both type and value dependent.

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