C++: Add BuiltInIntAddr class for __INTADDR__

cpp/ql/src/semmle/code/cpp/exprs/BuiltInOperations.qll

@@ -42,12 +42,19 @@ class BuiltInNoOp extends BuiltInOperation, @noopexpr {
 }
 
 /**
- * A C++ `__offsetof` expression (used by some implementations of offsetof in the presence of user-defined `operator&`).
+ * A C++ `__offsetof` expression (used by some implementations of offsetof in the presence of user-defined `operator&`).
  */
 class BuiltInOperationOffsetOf extends BuiltInOperation, @offsetofexpr {
   override string toString() { result = "__offsetof" }
 }
 
+/**
+ * A C/C++ `__INTADDR__` expression, used by EDG to implement `offsetof` in the presence of user-defined `operator&`.
+ */
+class BuiltInIntAddr extends BuiltInOperation, @intaddrexpr {
+  override string toString() { result = "__INTADDR__" }
+}
+
 /**
  * A C++ `__has_assign` expression (used by some implementations of the type_traits header).
  */

cpp/ql/test/library-tests/builtins/edg/expr.expected

@@ -8,6 +8,7 @@
 | edg.c:13:14:13:45 | (...) | 0 | 0 |
 | edg.c:13:14:13:45 | (mystruct *)... | 0 | 0 |
 | edg.c:13:14:13:45 | (size_t)... | 0 | 0 |
+| edg.c:13:14:13:45 | __INTADDR__ | 1 | 1 |
 | edg.c:13:43:13:44 | f2 | 0 | 0 |
 | file://:0:0:0:0 | 0 | 0 | 0 |
 | file://:0:0:0:0 | * ... | 0 | 0 |