Fixed #4461 (Warn about memset/memcpy on class with references as members)

lib/checkclass.cpp

@@ -1044,8 +1044,12 @@ void CheckClass::checkMemsetType(const Scope *start, const Token *tok, const Sco
     std::list<Variable>::const_iterator var;
 
     for (var = type->varlist.begin(); var != type->varlist.end(); ++var) {
+        if (var->isReference()) {
+            memsetErrorReference(tok, tok->str(), type->classDef->str());
+            continue;
+        }
         // don't warn if variable static or const, pointer or reference
-        if (!var->isStatic() && !var->isConst() && !var->isPointer() && !var->isReference()) {
+        if (!var->isStatic() && !var->isConst() && !var->isPointer()) {
             const Token *tok1 = var->typeStartToken();
             const Scope *typeScope = var->typeScope();
 
@@ -1090,6 +1094,12 @@ void CheckClass::memsetError(const Token *tok, const std::string &memfunc, const
     reportError(tok, Severity::error, "memsetClass", "Using '" + memfunc + "' on " + type + " that contains a " + classname + ".");
 }
 
+void CheckClass::memsetErrorReference(const Token *tok, const std::string &memfunc, const std::string &type)
+{
+    reportError(tok, Severity::error, "memsetClass", "Using '" + memfunc + "' on " + type + " that contains a reference.");
+}
+
+
 //---------------------------------------------------------------------------
 // ClassCheck: "void operator=(" and "const type & operator=("
 //---------------------------------------------------------------------------
@@ -1266,7 +1276,7 @@ void CheckClass::operatorEqToSelf()
     }
 }
 
-bool CheckClass::hasAllocation(const Function *func, const Scope* scope)
+bool CheckClass::hasAllocation(const Function *func, const Scope* scope) const
 {
     // This function is called when no simple check was found for assignment
     // to self.  We are currently looking for:
@@ -1573,7 +1583,7 @@ void CheckClass::checkConst()
     }
 }
 
-bool CheckClass::isMemberVar(const Scope *scope, const Token *tok)
+bool CheckClass::isMemberVar(const Scope *scope, const Token *tok) const
 {
     bool again = false;
 
@@ -1661,7 +1671,7 @@ static unsigned int countMinArgs(const Token* argList)
     return count;
 }
 
-bool CheckClass::isMemberFunc(const Scope *scope, const Token *tok)
+bool CheckClass::isMemberFunc(const Scope *scope, const Token *tok) const
 {
     unsigned int args = countParameters(tok);
 
@@ -1691,7 +1701,7 @@ bool CheckClass::isMemberFunc(const Scope *scope, const Token *tok)
     return false;
 }
 
-bool CheckClass::isConstMemberFunc(const Scope *scope, const Token *tok)
+bool CheckClass::isConstMemberFunc(const Scope *scope, const Token *tok) const
 {
     unsigned int args = countParameters(tok);
 

lib/checkclass.h

@@ -139,6 +139,7 @@ private:
     void operatorEqVarError(const Token *tok, const std::string &classname, const std::string &varname, bool inconclusive);
     void unusedPrivateFunctionError(const Token *tok, const std::string &classname, const std::string &funcname);
     void memsetError(const Token *tok, const std::string &memfunc, const std::string &classname, const std::string &type);
+    void memsetErrorReference(const Token *tok, const std::string &memfunc, const std::string &type);
     void mallocOnClassError(const Token* tok, const std::string &memfunc, const Token* classTok, const std::string &classname);
     void mallocOnClassWarning(const Token* tok, const std::string &memfunc, const Token* classTok);
     void operatorEqReturnError(const Token *tok, const std::string &className);
@@ -205,13 +206,13 @@ private:
     void checkReturnPtrThis(const Scope *scope, const Function *func, const Token *tok, const Token *last);
 
     // operatorEqToSelf helper functions
-    bool hasAllocation(const Function *func, const Scope* scope);
+    bool hasAllocation(const Function *func, const Scope* scope) const;
     static bool hasAssignSelf(const Function *func, const Token *rhs);
 
     // checkConst helper functions
-    bool isMemberVar(const Scope *scope, const Token *tok);
+    bool isMemberVar(const Scope *scope, const Token *tok) const;
-    bool isMemberFunc(const Scope *scope, const Token *tok);
+    bool isMemberFunc(const Scope *scope, const Token *tok) const;
-    bool isConstMemberFunc(const Scope *scope, const Token *tok);
+    bool isConstMemberFunc(const Scope *scope, const Token *tok) const;
     bool checkConstFunc(const Scope *scope, const Function *func, bool& memberAccessed);
 
     // constructors helper function

test/testclass.cpp

@@ -2284,6 +2284,24 @@ private:
                       "  memset(b,0,4);\n"
                       "}");
         ASSERT_EQUALS("", errout.str());
+
+        // #4461 Warn about memset/memcpy on class with references as members
+        checkNoMemset("class A {\n"
+                      "  std::string &s;\n"
+                      "};\n"
+                      "void f() {\n"
+                      "  A a;\n"
+                      "  memset(&a, 0, sizeof(a)); \n"
+                      "}");
+        ASSERT_EQUALS("[test.cpp:6]: (error) Using 'memset' on class that contains a reference.\n", errout.str());
+        checkNoMemset("class A {\n"
+                      "  const B&b;\n"
+                      "};\n"
+                      "void f() {\n"
+                      "  A a;\n"
+                      "  memset(&a, 0, sizeof(a)); \n"
+                      "}");
+        ASSERT_EQUALS("[test.cpp:6]: (error) Using 'memset' on class that contains a reference.\n", errout.str());
     }
 
     void memsetOnInvalid() { // Ticket #5425