Phan fails to warn about type mismatches for object with __toString **declared** without strict types

[TysonAndre]

This is because of the call to addAdditionalType

// src/Phan/Parse/ParseVisitor.php
//    public function visitMethod(Node $node): Context

        } elseif ('__tostring' === $method_name_lower) {
            if (!$this->context->isStrictTypes()) {
                $class->addAdditionalType(StringType::instance(false));
            }
            // In PHP 8 and later having a __toString method automatically adds the Stringable interface, #4476
            if (Config::get_closest_minimum_target_php_version_id() >= 80000) {
                // @phan-suppress-next-line PhanThrowTypeAbsentForCall should not happen, built in type
                $class->addAdditionalType(Type::fromFullyQualifiedString('\Stringable'));
            }
        }

<?php // b.php without strict_types
class HasToString { public function __toString() { return 'x'; }}

<?php // a.php
declare(strict_types=1);
require_once __DIR__ . '/b.php';
throw new Exception(new HasToString());