Fixed cppcheck-opensource#4995 (False positive - Using 'memset' on class that contains a virtual method) - Better fix

Author: lucasmrod

lib/checkclass.cpp

@@ -914,10 +914,6 @@ void CheckClass::noMemset()
                     // 3 arguments.
                     continue;
 
-                // Check if it's not a pointer to pointer
-                if (arg1->variable() && arg1->variable()->typeEndToken() &&
-                    Token::Match(arg1->variable()->typeEndToken()->previous(), "* *"))
-                    continue;
 
                 const Token *typeTok = 0;
                 const Scope *type = 0;
@@ -942,8 +938,12 @@ void CheckClass::noMemset()
 
                     const Variable *var = arg1->variable();
                     if (var && arg1->strAt(1) == ",") {
-                        if (var->isPointer())
+                        if (var->isPointer()) {
                             derefs--;
+                            if (var->typeEndToken() && Token::Match(var->typeEndToken()->previous(), "* *")) // Check if it's a pointer to pointer
+                                derefs--;
+                        }
+
                         if (var->isArray())
                             derefs -= (int)var->dimensions().size();
 

test/testclass.cpp

@@ -2406,16 +2406,19 @@ class TestClass : public TestFixture {
                       "    C* c1[10][10];\n"
                       "    C* c2[10];\n"
                       "    C c3[10][10];\n"
+                      "    C** c4 = new C*[10];\n"
                       "    memset(**c1, 0, 10);\n"
                       "    memset(*c1, 0, 10);\n"
                       "    memset(*c2, 0, 10);\n"
                       "    memset(*c3, 0, 10);\n"
+                      "    memset(*c4, 0, 10);\n"
                       "    memset(c2, 0, 10);\n"
                       "    memset(c3, 0, 10);\n"
                       "}");
-        ASSERT_EQUALS("[test.cpp:8]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
-                      "[test.cpp:10]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
-                      "[test.cpp:11]: (error) Using 'memset' on struct that contains a 'std::string'.\n", errout.str());
+        ASSERT_EQUALS("[test.cpp:9]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
+                      "[test.cpp:11]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
+                      "[test.cpp:12]: (error) Using 'memset' on struct that contains a 'std::string'.\n"
+                      "[test.cpp:13]: (error) Using 'memset' on struct that contains a 'std::string'.\n", errout.str());
     }
 
     void mallocOnClass() {