[clang] [analyzer] Improve handling of placement new in `PointerArith` (PR #155855)

[Alejandro Álvarez Ayllón via cfe-commits]

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@@ -165,3 +165,124 @@ void LValueToRValueBitCast_dumps(void *p, char (*array)[8]) {
 unsigned long ptr_arithmetic(void *p) {
   return __builtin_bit_cast(unsigned long, p) + 1; // no-crash
 }
+
+
+void escape(int*);
+
+struct AllocOpaqueFlag {};
+
+void* operator new(unsigned long, void *ptr) noexcept { return ptr; }
+void* operator new(unsigned long, void *ptr, AllocOpaqueFlag const&) noexcept { return ptr; }
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alejandro-alvarez-sonarsource wrote:

C&P mistake. Made them opaque, which makes one of the warning disappear (as it probably should).

https://github.com/llvm/llvm-project/pull/155855