Remove "this == nullptr" checks in CBOT, fixes #828

src/CBot/CBotClass.cpp

@@ -92,7 +92,7 @@ void CBotClass::ClearPublic()
 ////////////////////////////////////////////////////////////////////////////////
 void CBotClass::Purge()
 {
-    if ( this == nullptr ) return;
+    assert ( this != nullptr );
 
     delete      m_pVar;
     m_pVar      = nullptr;
@@ -104,7 +104,7 @@ void CBotClass::Purge()
 
     m_nbVar     = m_parent == nullptr ? 0 : m_parent->m_nbVar;
 
-    m_next->Purge();
+    if (m_next != nullptr) m_next->Purge();
     m_next = nullptr;          // no longer belongs to this chain
 }
 
@@ -205,7 +205,7 @@ std::string  CBotClass::GetName()
 ////////////////////////////////////////////////////////////////////////////////
 CBotClass*  CBotClass::GetParent()
 {
-    if ( this == nullptr ) return nullptr;
+    assert ( this != nullptr );
     return m_parent;
 }
 

src/CBot/CBotProgram.cpp

@@ -47,13 +47,13 @@ CBotProgram::CBotProgram(CBotVar* thisVar)
 CBotProgram::~CBotProgram()
 {
 //  delete  m_classes;
-    m_classes->Purge();
+    if (m_classes != nullptr) m_classes->Purge();
     m_classes = nullptr;
 
     CBotClass::FreeLock(this);
 
     delete m_functions;
-    m_stack->Delete();
+    if (m_stack != nullptr) m_stack->Delete();
 }
 
 bool CBotProgram::Compile(const std::string& program, std::vector<std::string>& functions, void* pUser)
@@ -62,7 +62,7 @@ bool CBotProgram::Compile(const std::string& program, std::vector<std::string>&
     Stop();
 
 //  delete      m_classes;
-    m_classes->Purge();      // purge the old definitions of classes
+    if (m_classes != nullptr) m_classes->Purge();      // purge the old definitions of classes
                             // but without destroying the object
     m_classes = nullptr;
     delete m_functions; m_functions = nullptr;
@@ -226,9 +226,12 @@ bool CBotProgram::Run(void* pUser, int timer)
 }
 
 void CBotProgram::Stop()
+{
+    if (m_stack != nullptr)
     {
         m_stack->Delete();
         m_stack = nullptr;
+    }
     m_entryPoint = nullptr;
     CBotClass::FreeLock(this);
 }
@@ -365,11 +368,15 @@ bool CBotProgram::RestoreState(FILE* pf)
     if (!ReadString( pf, s )) return false;
     Start(s);       // point de reprise
 
+    if (m_stack != nullptr)
+    {
         m_stack->Delete();
         m_stack = nullptr;
+    }
 
     // retrieves the stack from the memory
     // uses a nullptr pointer (m_stack) but it's ok like that
+    // TODO: no it's not okay like that! but it looks like it doesn't get optimized out at least ~krzys_h
     if (!m_stack->RestoreState(pf, m_stack)) return false;
     m_stack->SetProgram(this);                     // bases for routines
 

src/CBot/CBotStack.cpp

@@ -82,10 +82,10 @@ CBotStack* CBotStack::AllocateStack()
 ////////////////////////////////////////////////////////////////////////////////
 void CBotStack::Delete()
 {
-    if ( this == nullptr ) return;
+    assert ( this != nullptr );
 
-    m_next->Delete();
+    if (m_next != nullptr) m_next->Delete();
-    m_next2->Delete();
+    if (m_next2 != nullptr) m_next2->Delete();
 
     if (m_prev != nullptr)
     {
@@ -192,8 +192,8 @@ bool CBotStack::Return(CBotStack* pfils)
     m_var = pfils->m_var;                        // result transmitted
     pfils->m_var = nullptr;                        // not to destroy the variable
 
-    m_next->Delete();m_next = nullptr;                // releases the stack above
+    if (m_next != nullptr) m_next->Delete();m_next = nullptr;                // releases the stack above
-    m_next2->Delete();m_next2 = nullptr;            // also the second stack (catch)
+    if (m_next2 != nullptr) m_next2->Delete();m_next2 = nullptr;            // also the second stack (catch)
 
     return IsOk();                        // interrupted if error
 }
@@ -281,7 +281,7 @@ bool CBotStack::IfContinue(int state, const std::string& name)
     m_state = state;                            // where again?
     m_error = CBotNoErr;
     m_labelBreak.clear();
-    m_next->Delete();            // purge above stack
+    if (m_next != nullptr) m_next->Delete();            // purge above stack
     return true;
 }
 
@@ -478,7 +478,7 @@ bool CBotStack::Execute()
 
     if (!instr->Run(nullptr, pile)) return false;            // resume interrupted execution
 
-    pile->m_next->Delete();
+    if (pile->m_next != nullptr) pile->m_next->Delete();
 
     pile->m_callFinished = true;
     return true;

src/CBot/CBotVar/CBotVarClass.cpp

@@ -69,11 +69,10 @@ CBotVarClass::CBotVarClass(const CBotToken& name, const CBotTypResult& type)
     m_instances.insert(this);
 
     CBotClass* pClass = type.GetClass();
-    CBotClass* pClass2 = pClass->GetParent();
+    if ( pClass != nullptr && pClass->GetParent() != nullptr )
-    if ( pClass2 != nullptr )
     {
         // also creates an instance of the parent class
-        m_pParent = new CBotVarClass(name, CBotTypResult(type.GetType(),pClass2) ); //, nIdent);
+        m_pParent = new CBotVarClass(name, CBotTypResult(type.GetType(), pClass->GetParent()) ); //, nIdent);
     }
 
     SetClass( pClass );