Fixed false positive: Return value of std::remove() ignored when std::remove(char*) is called (#4093)

lib/checkstl.cpp

@@ -1340,7 +1340,7 @@ void CheckStl::uselessCalls()
                 uselessCallsSubstrError(tok, true);
         } else if (Token::Match(tok, "[{}:;] %var% . empty ( ) ;") && style)
             uselessCallsEmptyError(tok->next());
-        else if (Token::Match(tok, "[{};] std :: remove ("))
+		else if (Token::Match(tok, "[{};] std :: remove (") && tok->tokAt(5)->nextArgument())
             uselessCallsRemoveError(tok->next());
     }
 }

test/teststl.cpp

@@ -1941,6 +1941,7 @@ private:
               "    std::remove(a.begin(), a.end(), val);\n"
               "    x = std::remove(a.begin(), a.end(), val);\n"
               "    a.erase(std::remove(a.begin(), a.end(), val));\n"
+              "    std::remove(\"foo.txt\");\n"
               "}\n");
         ASSERT_EQUALS("[test.cpp:2]: (warning) Return value of std::remove() ignored. Elements remain in container.\n", errout.str());
     }