Fix false positives when class might inherit from VCL TObject class

Author: danmar

lib/checkclass.cpp

@@ -79,6 +79,28 @@ static bool isVariableCopyNeeded(const Variable &var)
            (var.valueType() && var.valueType()->type >= ValueType::Type::CHAR);
 }
 
+static bool isVcl(const Settings *settings)
+{
+    for (const std::string &library: settings->libraries) {
+        if (library == "vcl")
+            return true;
+    }
+    return false;
+}
+
+static bool isVclTypeInit(const Type *type)
+{
+    if (!type)
+        return false;
+    for (const Type::BaseInfo &baseInfo: type->derivedFrom) {
+        if (!baseInfo.type)
+            return true;
+        if (isVclTypeInit(baseInfo.type))
+            return true;
+    }
+    return false;
+}
+
 //---------------------------------------------------------------------------
 
 CheckClass::CheckClass(const Tokenizer *tokenizer, const Settings *settings, ErrorLogger *errorLogger)
@@ -101,6 +123,9 @@ void CheckClass::constructors()
 
     const bool printInconclusive = mSettings->certainty.isEnabled(Certainty::inconclusive);
     for (const Scope * scope : mSymbolDatabase->classAndStructScopes) {
+        if (isVcl(mSettings) && isVclTypeInit(scope->definedType))
+            continue;
+
         const bool unusedTemplate = Token::simpleMatch(scope->classDef->previous(), ">");
 
         bool usedInUnion = false;

test/testconstructors.cpp

@@ -47,6 +47,20 @@ class TestConstructors : public TestFixture {
         checkClass.constructors();
     }
 
+    void check(const char code[], const Settings &s) {
+        // Clear the error buffer..
+        errout.str("");
+
+        // Tokenize..
+        Tokenizer tokenizer(&s, this);
+        std::istringstream istr(code);
+        tokenizer.tokenize(istr, "test.cpp");
+
+        // Check class constructors..
+        CheckClass checkClass(&tokenizer, &s, this);
+        checkClass.constructors();
+    }
+
     void run() OVERRIDE {
         settings.severity.enable(Severity::style);
         settings.severity.enable(Severity::warning);
@@ -176,6 +190,7 @@ class TestConstructors : public TestFixture {
         TEST_CASE(privateCtor2);           // If constructor is private..
         TEST_CASE(function);               // Function is not variable
         TEST_CASE(uninitVarPublished);     // Borland C++: Variables in the published section are auto-initialized
+        TEST_CASE(uninitVarInheritClassInit); // Borland C++: if class inherits from TObject, all variables are initialized
         TEST_CASE(uninitOperator);         // No FP about uninitialized 'operator[]'
         TEST_CASE(uninitFunction1);        // No FP when initialized in function
         TEST_CASE(uninitFunction2);        // No FP when initialized in function
@@ -3163,6 +3178,20 @@ class TestConstructors : public TestFixture {
         ASSERT_EQUALS("", errout.str());
     }
 
+    void uninitVarInheritClassInit() {
+        Settings s;
+        s.libraries.emplace_back("vcl");
+
+        check("class Fred: public TObject\n"
+              "{\n"
+              "public:\n"
+              "    Fred() { }\n"
+              "private:\n"
+              "    int x;\n"
+              "};", s);
+        ASSERT_EQUALS("", errout.str());
+    }
+
     void uninitOperator() {
         check("class Fred\n"
               "{\n"