fix #3062 (false negative: Boolean variable is used in bitwise operation)

lib/checkother.cpp

@@ -220,6 +220,38 @@ void CheckOther::clarifyConditionError(const Token *tok, bool assign, bool boolo
                 errmsg);
 }
 
+//---------------------------------------------------------------------------
+// if (bool & bool) -> if (bool && bool)
+// if (bool | bool) -> if (bool || bool)
+//---------------------------------------------------------------------------
+void CheckOther::checkBitwiseOnBoolean()
+{
+    if (!_settings->isEnabled("style"))
+        return;
+
+    for (const Token *tok = _tokenizer->tokens(); tok; tok = tok->next())
+    {
+        if (Token::Match(tok, "(|.|return %var% [&|]"))
+        {
+            if (tok->next()->varId())
+            {
+                const Variable *var = _tokenizer->getSymbolDatabase()->getVariableFromVarId(tok->next()->varId());
+                if (var && (var->typeStartToken() == var->typeEndToken()) &&
+                    Token::Match(var->typeStartToken(), "bool|_Bool"))
+                {
+                    bitwiseOnBooleanError(tok->next(), tok->next()->str(), tok->strAt(2) == "&" ? "&&" : "||");
+                }
+            }
+        }
+    }
+}
+
+void CheckOther::bitwiseOnBooleanError(const Token *tok, const std::string &varname, const std::string &op)
+{
+    reportError(tok, Severity::style, "bitwiseOnBoolean",
+                "Boolean variable '" + varname + "' is used in bitwise operation. Did you mean " + op + " ?");
+}
+
 //---------------------------------------------------------------------------
 //---------------------------------------------------------------------------
 void CheckOther::warningOldStylePointerCast()

lib/checkother.h

@@ -102,6 +102,7 @@ public:
 
         checkOther.checkAssignBoolToPointer();
         checkOther.checkSignOfUnsignedVariable();
+        checkOther.checkBitwiseOnBoolean();
     }
 
     /** @brief Clarify calculation for ".. a * b ? .." */
@@ -225,6 +226,9 @@ public:
     /** @brief %Check for testing sign of unsigned variable */
     void checkSignOfUnsignedVariable();
 
+    /** @brief %Check for using bool in bitwise expression */
+    void checkBitwiseOnBoolean();
+
     // Error messages..
     void cstyleCastError(const Token *tok);
     void dangerousUsageStrtolError(const Token *tok);
@@ -261,6 +265,7 @@ public:
     void assignBoolToPointerError(const Token *tok);
     void unsignedLessThanZeroError(const Token *tok, const std::string &varname);
     void unsignedPositiveError(const Token *tok, const std::string &varname);
+    void bitwiseOnBooleanError(const Token *tok, const std::string &varname, const std::string &op);
 
     void getErrorMessages(ErrorLogger *errorLogger, const Settings *settings)
     {
@@ -309,6 +314,7 @@ public:
         c.duplicateBreakError(0);
         c.unsignedLessThanZeroError(0, "varname");
         c.unsignedPositiveError(0, "varname");
+        c.bitwiseOnBooleanError(0, "varname", "&&");
     }
 
     std::string myName() const
@@ -357,6 +363,7 @@ public:
                "* duplicate break statement\n"
                "* testing if unsigned variable is negative\n"
                "* testing is unsigned variable is positive\n"
+               "* using bool in bitwise expression\n"
 
                // optimisations
                "* optimisation: detect post increment/decrement\n";

test/testother.cpp

@@ -119,6 +119,7 @@ private:
         TEST_CASE(clarifyCondition1);     // if (a = b() < 0)
         TEST_CASE(clarifyCondition2);     // if (a & b == c)
         TEST_CASE(clarifyCondition3);     // if (! a & b)
+        TEST_CASE(bitwiseOnBoolean);      // if (bool & bool)
 
         TEST_CASE(incorrectStringCompare);
 
@@ -160,6 +161,7 @@ private:
         checkOther.checkDuplicateIf();
         checkOther.checkDuplicateBranch();
         checkOther.checkDuplicateExpression();
+        checkOther.checkBitwiseOnBoolean();
 
         // Simplify token list..
         tokenizer.simplifyTokenList();
@@ -2815,6 +2817,63 @@ private:
         ASSERT_EQUALS("", errout.str());
     }
 
+    void bitwiseOnBoolean() // 3062
+    {
+        check("void f(_Bool a, _Bool b) {\n"
+              "    if(a & b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean && ?\n", errout.str());
+
+        check("void f(_Bool a, _Bool b) {\n"
+              "    if(a | b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean || ?\n", errout.str());
+
+        check("void f(bool a, bool b) {\n"
+              "    if(a & b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean && ?\n", errout.str());
+
+        check("void f(bool a, bool b) {\n"
+              "    if(a & !b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean && ?\n", errout.str());
+
+        check("void f(bool a, bool b) {\n"
+              "    if(a | b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean || ?\n", errout.str());
+
+        check("void f(bool a, bool b) {\n"
+              "    if(a | !b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:2]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean || ?\n", errout.str());
+
+        check("bool a, b;\n"
+              "void f() {\n"
+              "    if(a & b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean && ?\n", errout.str());
+
+        check("bool a, b;\n"
+              "void f() {\n"
+              "    if(a & !b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean && ?\n", errout.str());
+
+        check("bool a, b;\n"
+              "void f() {\n"
+              "    if(a | b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean || ?\n", errout.str());
+
+        check("bool a, b;\n"
+              "void f() {\n"
+              "    if(a | !b) {}\n"
+              "}");
+        ASSERT_EQUALS("[test.cpp:3]: (style) Boolean variable 'a' is used in bitwise operation. Did you mean || ?\n", errout.str());
+    }
+
     void incorrectStringCompare()
     {
         check("int f() {\n"