Allow Destruct to call only the destructor without delete/free.

Author: vgvassilev

include/clang/Interpreter/CppInterOp.h

@@ -262,8 +262,10 @@ namespace Cpp {
   TCppObject_t Construct(TInterp_t interp, TCppScope_t scope,
                          void *arena = nullptr);
 
-  /// Calls the destructor of object of type \c type.
-  void Destruct(TInterp_t interp, TCppObject_t This, TCppScope_t type);
+  /// Calls the destructor of object of type \c type. When withFree is true it
+  /// calls operator delete/free.
+  void Destruct(TInterp_t interp, TCppObject_t This, TCppScope_t type,
+                bool withFree = true);
 } // end namespace Cpp
 
 #endif // CPPINTEROP_CPPINTEROP_H

lib/Interpreter/CppInterOp.cpp

@@ -2873,11 +2873,12 @@ namespace Cpp {
     return nullptr;
   }
 
-  void Destruct(TInterp_t interp, TCppObject_t This, TCppScope_t scope) {
+  void Destruct(TInterp_t interp, TCppObject_t This, TCppScope_t scope,
+                bool withFree /*=true*/) {
     Decl* Class = (Decl*)scope;
     auto *I = (compat::Interpreter *)interp;
     if (CallFuncDtorWrapper_t wrapper = make_dtor_wrapper(I, Class)) {
-      (*wrapper)(This, /*nary=*/0, /*withFree=*/true);
+      (*wrapper)(This, /*nary=*/0, withFree);
       return;
     }
     // FIXME: Diagnose.

unittests/CppInterOp/FunctionReflectionTest.cpp

@@ -718,4 +718,10 @@ TEST(FunctionReflectionTest, Destruct) {
   std::string output = testing::internal::GetCapturedStdout();
 
   EXPECT_EQ(output, "Destructor Executed");
+
+  object = Cpp::Construct(Interp.get(), scope);
+  // Make sure we do not call delete by adding an explicit Deallocate. If we
+  // called delete the Deallocate will cause a double deletion error.
+  Cpp::Destruct(Interp.get(), object, scope, /*withFree=*/false);
+  Cpp::Deallocate(scope, object);
 }