Fix #11803 FP uselessOverride - overloaded virtual member function (#5211)

Author: chrchr-github

lib/checkclass.cpp

@@ -3087,6 +3087,12 @@ void CheckClass::checkUselessOverride()
             const Function* baseFunc = func.getOverriddenFunction();
             if (!baseFunc || baseFunc->isPure() || baseFunc->access != func.access)
                 continue;
+            if (std::any_of(classScope->functionList.begin(), classScope->functionList.end(), [&func](const Function& f) { // check for overloads
+                if (&f == &func)
+                    return false;
+                return f.name() == func.name();
+            }))
+                continue;
             if (const Token* const call = getSingleFunctionCall(func.functionScope)) {
                 if (call->function() != baseFunc)
                     continue;

test/testclass.cpp

@@ -8429,6 +8429,17 @@ class TestClass : public TestFixture {
                              "    B::f(a, b, m);\n"
                              "};");
         ASSERT_EQUALS("", errout.str());
+
+        checkUselessOverride("struct B {\n" // #11803
+                             "    virtual void f();\n"
+                             "    virtual void f(int i);\n"
+                             "};\n"
+                             "struct D : B {\n"
+                             "    void f() override { B::f(); }\n"
+                             "    void f(int i) override;\n"
+                             "    void g() { f(); }\n"
+                             "};");
+        ASSERT_EQUALS("", errout.str());
     }
 
 #define checkUnsafeClassRefMember(code) checkUnsafeClassRefMember_(code, __FILE__, __LINE__)