Fix #14581 FP missingOverride for uninstantiated template overload (danmar#8322)

Author: chrchr-github

lib/checkclass.cpp

@@ -3271,6 +3271,8 @@ void CheckClass::checkOverride()
                 continue;
             if (func.tokenDef->isExpandedMacro())
                 continue;
+            if (func.templateDef)
+                continue;
             const Function *baseFunc = func.getOverriddenFunction();
             if (baseFunc)
                 overrideError(baseFunc, &func);

test/testclass.cpp

@@ -8842,6 +8842,16 @@ class TestClass : public TestFixture {
                       "};\n");
         ASSERT_EQUALS("[test.cpp:2:14] -> [test.cpp:5:6]: (style) The destructor '~D' overrides a destructor in a base class but is not marked with a 'override' specifier. [missingOverride]\n",
                       errout_str());
+
+        checkOverride("struct B {\n" // #14581
+                      "    virtual void f();\n"
+                      "};\n"
+                      "struct D : B {\n"
+                      "    void f() override;\n"
+                      "    template <typename T>\n"
+                      "    void f();\n"
+                      "};\n");
+        ASSERT_EQUALS("", errout_str());
     }
 
     void overrideCVRefQualifiers() {