[clang] [LifetimeSafety] Add support for `new`/`delete` (PR #192504)

[Utkarsh Saxena via cfe-commits]

================
@@ -2663,6 +2663,259 @@ int *noreturn_dead_nested(bool cond, bool cond2, int *num) {
 
 } // namespace conditional_operator_control_flow
 
+namespace heap_allocation {
+
+//===----------------------------------------------------------------------===//
+// new
+//===----------------------------------------------------------------------===//
+
+void new_view_from_dead_scope() {
+  View *p;
+  {
+    MyObj obj;
+    p = new View(obj); // expected-warning {{object whose reference is captured does not live long enough}}
+  }                    // expected-note {{destroyed here}}
+  p->use();            // expected-note {{later used here}}
+}
+
+void new_int_basic() {
+  int *p = new int; // expected-warning {{allocated object does not live long enough}}
+  delete p;         // expected-note {{freed here}}
+  (void)*p;         // expected-note {{later used here}}
+}
+
----------------
usx95 wrote:

Test idea:

```cpp
struct MultiView {
  MultiView(MyObj& a [[clang::lifetimebound]], MyObj& b [[clang::lifetimebound]]);
};

void new_multiview_from_mixed_scope() {
  MyObj obj1;
  MultiView *p;
  {
    MyObj obj2;
    p = new MultiView(obj1, obj2); // Should warn about obj2.
  }
  (void)p;
}

```



https://github.com/llvm/llvm-project/pull/192504