Improve Fix #6180 ("reset" and "clear" clears the move status)

Author: zingsheim

lib/checkother.cpp

@@ -2713,7 +2713,7 @@ void CheckOther::checkAccessOfMovedVariable()
         }
         for (const Token* tok = scopeStart->next(); tok != scope->classEnd; tok = tok->next()) {
             const ValueFlow::Value * movedValue = tok->getMovedValue();
-            if (!movedValue)
+            if (!movedValue || movedValue->moveKind == ValueFlow::Value::NonMovedVariable)
                 continue;
             if (movedValue->inconclusive && !reportInconclusive)
                 continue;
@@ -2766,6 +2766,8 @@ void CheckOther::accessMovedError(const Token *tok, const std::string &varname,
         errorId = "accessForwarded";
         kindString = "forwarded";
         break;
+    default:
+        return;
     }
     const std::string errmsg(std::string("Access of ") + kindString + " variable " + varname + ".");
     reportError(tok, Severity::warning, errorId, errmsg, CWE(0U), inconclusive);

lib/valueflow.cpp

@@ -1760,6 +1760,24 @@ static void valueFlowAfterMove(TokenList *tokenlist, SymbolDatabase* symboldatab
 
         for (Token* tok = const_cast<Token*>(start); tok != scope->classEnd; tok = tok->next()) {
             Token * varTok;
+            if (Token::Match(tok, "%var% . reset|clear (") && tok->next()->originalName() == emptyString) {
+                varTok = tok;
+                ValueFlow::Value value;
+                value.valueType = ValueFlow::Value::MOVED;
+                value.moveKind = ValueFlow::Value::NonMovedVariable;
+                value.setKnown();
+                std::list<ValueFlow::Value> values;
+                values.push_back(value);
+
+                const Variable *var = varTok->variable();
+                if (!var || (!var->isLocal() && !var->isArgument()))
+                    continue;
+                const unsigned int varId = varTok->varId();
+                const Token * const endOfVarScope = var->typeStartToken()->scope()->classEnd;
+                setTokenValue(varTok, value, settings);
+                valueFlowForward(varTok->next(), endOfVarScope, var, varId, values, false, tokenlist, errorLogger, settings);
+                continue;
+            }
             ValueFlow::Value::MoveKind moveKind;
             if (!isStdMoveOrStdForwarded(tok, &moveKind, &varTok))
                 continue;

lib/valueflow.h

@@ -92,7 +92,7 @@ namespace ValueFlow {
         double floatValue;
 
         /** kind of moved  */
-        enum MoveKind {MovedVariable, ForwardedVariable} moveKind;
+        enum MoveKind {NonMovedVariable, MovedVariable, ForwardedVariable} moveKind;
 
         /** For calculated values - variable value that calculated value depends on */
         long long varvalue;
@@ -114,6 +114,8 @@ namespace ValueFlow {
 
         static const char * toString(MoveKind moveKind) {
             switch (moveKind) {
+            case NonMovedVariable:
+                return "NonMovedVariable";
             case MovedVariable:
                 return "MovedVariable";
             case ForwardedVariable:

test/testother.cpp

@@ -6228,12 +6228,7 @@ class TestOther : public TestFixture {
               "    h(a);\n"
               "}");
         ASSERT_EQUALS("[test.cpp:4]: (warning) Access of moved variable a.\n"
-                      "[test.cpp:5]: (warning, inconclusive) Access of moved variable a.\n"
-                      "[test.cpp:6]: (warning, inconclusive) Access of moved variable a.\n"
-                      "[test.cpp:7]: (warning, inconclusive) Access of moved variable a.\n"
-                      "[test.cpp:8]: (warning) Access of moved variable a.\n"
-                      "[test.cpp:9]: (warning, inconclusive) Access of moved variable a.\n"
-                      "[test.cpp:10]: (warning, inconclusive) Access of moved variable a.\n", errout.str());
+                      "[test.cpp:8]: (warning) Access of moved variable a.\n", errout.str());
     }
 
     void moveAndFunctionParameter() {
@@ -6301,8 +6296,7 @@ class TestOther : public TestFixture {
               "    v.clear();\n"
               "    if (v.empty()) {}\n"
               "}");
-        ASSERT_EQUALS("[test.cpp:4]: (warning, inconclusive) Access of moved variable v.\n"
-                      "[test.cpp:5]: (warning, inconclusive) Access of moved variable v.\n", errout.str());
+        ASSERT_EQUALS("", errout.str());
     }
 
     void movedPointer() {