Fixed #2467 (false positive: possible nullptr dereference)

lib/checknullpointer.cpp

@@ -32,6 +32,16 @@ CheckNullPointer instance;
 //---------------------------------------------------------------------------
 
 
+/** Is string uppercase? */
+bool CheckNullPointer::isUpper(const std::string &str)
+{
+    for (unsigned int i = 0; i < str.length(); ++i)
+    {
+        if (str[i] >= 'a' && str[i] <= 'z')
+            return false;
+    }
+    return true;
+}
 
 /**
  * @brief parse a function call and extract information about variable usage
@@ -526,6 +536,17 @@ void CheckNullPointer::nullPointerByCheckAndDeRef()
             // - if there are logical operators
             // - if (x) { } else { ... }
 
+            // If the if-body ends with a unknown macro then bailout
+            {
+                // goto the end paranthesis
+                const Token *endpar = tok->next()->link();
+                const Token *endbody = endpar ? endpar->next()->link() : 0;
+                if (endbody &&
+                    Token::Match(endbody->tokAt(-3), "[;{}] %var% ;") &&
+                    isUpper(endbody->tokAt(-2)->str()))
+                    continue;
+            }
+
             // vartok : token for the variable
             const Token *vartok = 0;
             if (Token::Match(tok, "if ( ! %var% ) {"))

lib/checknullpointer.h

@@ -60,6 +60,9 @@ public:
         checkNullPointer.executionPaths();
     }
 
+    /** Is string uppercase? */
+    static bool isUpper(const std::string &str);
+
     /**
      * @brief parse a function call and extract information about variable usage
      * @param tok first token

lib/checkuninitvar.cpp

@@ -33,18 +33,6 @@ CheckUninitVar instance;
 
 //---------------------------------------------------------------------------
 
-/** Is string uppercase? */
-static bool isUpper(const std::string &str)
-{
-    for (unsigned int i = 0; i < str.length(); ++i)
-    {
-        if (str[i] >= 'a' && str[i] <= 'z')
-            return false;
-    }
-    return true;
-}
-
-
 /// @addtogroup Checks
 /// @{
 
@@ -679,7 +667,7 @@ private:
                 }
 
                 // ticket #2367 : unexpanded macro that uses sizeof|typeof?
-                else if (Token::Match(tok2, "%type% (") && isUpper(tok2->str()))
+                else if (Token::Match(tok2, "%type% (") && CheckNullPointer::isUpper(tok2->str()))
                 {
                     tok2 = tok2->next()->link();
                     if (!tok2)
@@ -703,7 +691,7 @@ private:
                         functionCall = functionCall ? functionCall->previous() : 0;
                         if (functionCall)
                         {
-                            if (functionCall->isName() && !isUpper(functionCall->str()) && use_dead_pointer(checks, tok2))
+                            if (functionCall->isName() && !CheckNullPointer::isUpper(functionCall->str()) && use_dead_pointer(checks, tok2))
                                 ExecutionPath::bailOutVar(checks, tok2->varId());
                         }
                     }

test/testnullpointer.cpp

@@ -859,6 +859,15 @@ private:
               "    *p = 0;\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:5]: (error) Possible null pointer dereference: p\n", errout.str());
+
+        // #2467 - unknown macro may terminate the application
+        check("void f(Fred *fred) {\n"
+              "    if (fred == NULL) {\n"
+              "        MACRO;\n"
+              "    }\n"
+              "    fred->a();\n"
+              "}");
+        ASSERT_EQUALS("", errout.str());
     }
 
     // Test CheckNullPointer::nullConstantDereference