PHP A non-numeric value encountered Warning

[wyclef]

Hi, I am getting a non-numeric value encountered warning on the line with the + in PHP 7.4. If I change the following from

// Color picker
                case "color":
                    $default_color = '';
                    if ( isset($value['std']) ) {
                        if ( $smof_data[$value['id']] !=  $value['std'] )
 +                            $default_color = ' data-default-color="' .$value['std'] . '" ';
                    }
                    $output .= '<input name="' . $value['id'] . '" id="' . $value['id'] . '" class="of-color"  type="text" value="' . $smof_data[$value['id']] . '"' . $default_color .' />';
            
                break;

and add an (int) to

// Color picker
                case "color":
                    $default_color = '';
                    if ( isset($value['std']) ) {
                        if ( (int)$smof_data[$value['id']] !=  $value['std'] )
 +                            $default_color = ' data-default-color="' .$value['std'] . '" ';
                    }
                    $output .= '<input name="' . $value['id'] . '" id="' . $value['id'] . '" class="of-color"  type="text" value="' . $smof_data[$value['id']] . '"' . $default_color .' />';
            
                break;

The error goes away but shouldn’t I also be adding an (int) in front of $default_color too? Basing this on this link Warning: A non-numeric value encountered

 

[EkBass]

if ( (int)$smof_data[$value['id']] != $value['std'] )

That compares the integer value of $smof_data[$value['id']] to $value['std'] ) which is type of what? If its boolean, double, string, char, floating etc. it causes an warning or error depending of context.