Checking in fix for issue 9957 - - False negative: duplInheritedMember (#2964)

lib/checkclass.cpp

@@ -2439,22 +2439,28 @@ void CheckClass::checkDuplInheritedMembers()
     // Iterate over all classes
     for (const Type &classIt : mSymbolDatabase->typeList) {
         // Iterate over the parent classes
-        for (const Type::BaseInfo &parentClassIt : classIt.derivedFrom) {
+        checkDuplInheritedMembersRecursive(&classIt, &classIt);
+    }
+}
+
+void CheckClass::checkDuplInheritedMembersRecursive(const Type* typeCurrent, const Type* typeBase)
+{
+    for (const Type::BaseInfo &parentClassIt : typeBase->derivedFrom) {
         // Check if there is info about the 'Base' class
         if (!parentClassIt.type || !parentClassIt.type->classScope)
             continue;
         // Check if they have a member variable in common
-            for (const Variable &classVarIt : classIt.classScope->varlist) {
+        for (const Variable &classVarIt : typeCurrent->classScope->varlist) {
             for (const Variable &parentClassVarIt : parentClassIt.type->classScope->varlist) {
                 if (classVarIt.name() == parentClassVarIt.name() && !parentClassVarIt.isPrivate()) { // Check if the class and its parent have a common variable
                     duplInheritedMembersError(classVarIt.nameToken(), parentClassVarIt.nameToken(),
-                                                  classIt.name(), parentClassIt.type->name(), classVarIt.name(),
+                                                typeCurrent->name(), parentClassIt.type->name(), classVarIt.name(),
-                                                  classIt.classScope->type == Scope::eStruct,
+                                                typeCurrent->classScope->type == Scope::eStruct,
                                                 parentClassIt.type->classScope->type == Scope::eStruct);
                 }
             }
         }
-        }
+        checkDuplInheritedMembersRecursive(typeCurrent, parentClassIt.type);
     }
 }
 

lib/checkclass.h

@@ -38,6 +38,7 @@ class Scope;
 class Settings;
 class SymbolDatabase;
 class Token;
+class Type;
 
 /// @addtogroup Checks
 /// @{
@@ -185,6 +186,7 @@ private:
     void overrideError(const Function *funcInBase, const Function *funcInDerived);
     void thisUseAfterFree(const Token *self, const Token *free, const Token *use);
     void unsafeClassRefMemberError(const Token *tok, const std::string &varname);
+    void checkDuplInheritedMembersRecursive(const Type* typeCurrent, const Type* typeBase);
 
     void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings) const OVERRIDE {
         CheckClass c(nullptr, settings, errorLogger);

test/testclass.cpp

@@ -557,6 +557,20 @@ private:
                                   "}");
         ASSERT_EQUALS("", errout.str());
 
+        // #9957
+        checkDuplInheritedMembers("class Base {\n"
+                                  "    public:\n"
+                                  "        int i;\n"
+                                  "};\n"
+                                  "class Derived1: public Base {\n"
+                                  "    public:\n"
+                                  "        int j;\n"
+                                  "};\n"
+                                  "class Derived2 : public Derived1 {\n"
+                                  "    int i;\n"  
+                                  "};");
+        ASSERT_EQUALS("[test.cpp:3] -> [test.cpp:10]: (warning) The class 'Derived2' defines member variable with name 'i' also defined in its parent class 'Base'.\n", errout.str());        
+
     }
 
     void checkCopyConstructor(const char code[]) {