Fixed #1440 (false negative: memory leak (function parameters))

lib/checkmemoryleak.cpp

@@ -2108,11 +2108,27 @@ void CheckMemoryLeakInFunction::checkScope(const Token *Tok1, const std::string
 // Checks for memory leaks inside function..
 //---------------------------------------------------------------------------
 
-void CheckMemoryLeakInFunction::parseFunctionScope(const Token *tok, const bool classmember)
+void CheckMemoryLeakInFunction::parseFunctionScope(const Token *tok, const Token *tok1, const bool classmember)
 {
     // Check locking/unlocking of global resources..
     checkScope(tok->next(), "", 0, classmember, 1);
 
+    // Locate parameters and check their usage..
+    for (const Token *tok2 = tok1; tok2; tok2 = tok2->next())
+    {
+        if (tok2 == tok)
+            break;
+        if (tok2->str() == ")")
+            break;
+        if (Token::Match(tok2, "[(,] %type% * %var% [,)]") && tok2->next()->isStandardType())
+        {
+            const std::string varname(tok2->strAt(3));
+            const unsigned int varid = tok2->tokAt(3)->varId();
+            const unsigned int sz = _tokenizer->sizeOfType(tok->next());
+            checkScope(tok->next(), varname, varid, classmember, sz);
+        }
+    }
+
     // Locate variable declarations and check their usage..
     unsigned int indentlevel = 0;
     do
@@ -2187,9 +2203,10 @@ void CheckMemoryLeakInFunction::check()
         // Found a function scope
         if (Token::Match(tok, ") const| {"))
         {
+            const Token * const tok1 = tok->link();
             while (tok->str() != "{")
                 tok = tok->next();
-            parseFunctionScope(tok, classmember);
+            parseFunctionScope(tok, tok1, classmember);
             tok = tok->link();
             continue;
         }

lib/checkmemoryleak.h

@@ -193,10 +193,11 @@ public:
 
     /**
      * @brief %Check all variables in function scope
-     * @param tok The first '{' token of the function scope
+     * @param tok The first '{' token of the function body
+     * @param tok1 The '(' token in the function declaration
      * @param classmember Is this function a class member?
      */
-    void parseFunctionScope(const Token *tok, const bool classmember);
+    void parseFunctionScope(const Token *tok, const Token *tok1, const bool classmember);
 
     /**
      * @brief %Check if there is a "p = foo(p, .." and foo returns the argument (p)

test/testmemleak.cpp

@@ -381,6 +381,9 @@ private:
         TEST_CASE(knownFunctions);
 
         TEST_CASE(same_function_name);
+
+        // #1440 - Check function parameters also..
+        TEST_CASE(functionParameter);
     }
 
 
@@ -2688,6 +2691,15 @@ private:
               "}\n");
         ASSERT_EQUALS("", errout.str());
     }
+
+    void functionParameter()
+    {
+        check("void a(char *p)\n"
+              "{\n"
+              "    p = malloc(100);\n"
+              "}\n");
+        ASSERT_EQUALS("[test.cpp:4]: (error) Memory leak: p\n", errout.str());
+    }
 };
 
 static TestMemleakInFunction testMemleakInFunction;