null pointers: fixed a false positive

src/checkother.cpp

@@ -1042,6 +1042,9 @@ void CheckOther::nullPointer()
                 if (varid == 0)
                     continue;
 
+                if (Token::Match(tok2->tokAt(-2), "%varid% ?", varid))
+                    continue;
+
                 // Check usage of dereferenced variable in the loop..
                 unsigned int indentlevel3 = 0;
                 for (const Token *tok3 = tok1->next()->link(); tok3; tok3 = tok3->next())

test/testother.cpp

@@ -446,6 +446,16 @@ private:
                          "    }\n"
                          "}\n");
         ASSERT_EQUALS("[test.cpp:3]: (error) Possible null pointer dereference\n", errout.str());
+
+        checkNullPointer("void foo()\n"
+                         "{\n"
+                         "    for (const Token *tok = tokens; tok; tok = tok ? tok->next() : NULL)\n"
+                         "    {\n"
+                         "        while (tok && tok->str() != \";\")\n"
+                         "            tok = tok->next();\n"
+                         "    }\n"
+                         "}\n");
+        ASSERT_EQUALS("", errout.str());
     }
 
     void nullpointer2()