diff --git a/src/Iconv/bootstrap80.php b/src/Iconv/bootstrap80.php
index 04b1473b7..6be91ff37 100644
--- a/src/Iconv/bootstrap80.php
+++ b/src/Iconv/bootstrap80.php
@@ -25,19 +25,19 @@
 }
 
 if (!function_exists('iconv')) {
-    function iconv(?string $from_encoding, ?string $to_encoding, ?string $string): string|false { return p\Iconv::iconv((string) $from_encoding, (string) $to_encoding, (string) $string); }
+    function iconv(string $from_encoding, string $to_encoding, string $string): string|false { return p\Iconv::iconv((string) $from_encoding, (string) $to_encoding, (string) $string); }
 }
 if (!function_exists('iconv_get_encoding')) {
-    function iconv_get_encoding(?string $type = 'all'): array|string|false { return p\Iconv::iconv_get_encoding((string) $type); }
+    function iconv_get_encoding(string $type = 'all'): array|string|false { return p\Iconv::iconv_get_encoding((string) $type); }
 }
 if (!function_exists('iconv_set_encoding')) {
-    function iconv_set_encoding(?string $type, ?string $encoding): bool { return p\Iconv::iconv_set_encoding((string) $type, (string) $encoding); }
+    function iconv_set_encoding(string $type, string $encoding): bool { return p\Iconv::iconv_set_encoding((string) $type, (string) $encoding); }
 }
 if (!function_exists('iconv_mime_encode')) {
-    function iconv_mime_encode(?string $field_name, ?string $field_value, ?array $options = []): string|false { return p\Iconv::iconv_mime_encode((string) $field_name, (string) $field_value, (array) $options); }
+    function iconv_mime_encode(string $field_name, string $field_value, array $options = []): string|false { return p\Iconv::iconv_mime_encode((string) $field_name, (string) $field_value, (array) $options); }
 }
 if (!function_exists('iconv_mime_decode_headers')) {
-    function iconv_mime_decode_headers(?string $headers, ?int $mode = 0, ?string $encoding = null): array|false { return p\Iconv::iconv_mime_decode_headers((string) $headers, (int) $mode, $encoding); }
+    function iconv_mime_decode_headers(string $headers, int $mode = 0, ?string $encoding = null): array|false { return p\Iconv::iconv_mime_decode_headers((string) $headers, (int) $mode, $encoding); }
 }
 
 if (extension_loaded('mbstring')) {
@@ -59,22 +59,22 @@ function iconv_mime_decode($string, $mode = 0, $encoding = null) { $currentMbEnc
 } else {
     if (!function_exists('iconv_strlen')) {
         if (extension_loaded('xml')) {
-            function iconv_strlen(?string $string, ?string $encoding = null): int|false { return p\Iconv::strlen1((string) $string, $encoding); }
+            function iconv_strlen(string $string, ?string $encoding = null): int|false { return p\Iconv::strlen1((string) $string, $encoding); }
         } else {
-            function iconv_strlen(?string $string, ?string $encoding = null): int|false { return p\Iconv::strlen2((string) $string, $encoding); }
+            function iconv_strlen(string $string, ?string $encoding = null): int|false { return p\Iconv::strlen2((string) $string, $encoding); }
         }
     }
 
     if (!function_exists('iconv_strpos')) {
-        function iconv_strpos(?string $haystack, ?string $needle, ?int $offset = 0, ?string $encoding = null): int|false { return p\Iconv::iconv_strpos((string) $haystack, (string) $needle, (int) $offset, $encoding); }
+        function iconv_strpos(string $haystack, string $needle, int $offset = 0, ?string $encoding = null): int|false { return p\Iconv::iconv_strpos((string) $haystack, (string) $needle, (int) $offset, $encoding); }
     }
     if (!function_exists('iconv_strrpos')) {
-        function iconv_strrpos(?string $haystack, ?string $needle, ?string $encoding = null): int|false { return p\Iconv::iconv_strrpos((string) $haystack, (string) $needle, $encoding); }
+        function iconv_strrpos(string $haystack, string $needle, ?string $encoding = null): int|false { return p\Iconv::iconv_strrpos((string) $haystack, (string) $needle, $encoding); }
     }
     if (!function_exists('iconv_substr')) {
-        function iconv_substr(?string $string, ?int $offset, ?int $length = null, ?string $encoding = null): string|false { return p\Iconv::iconv_substr((string) $string, (string) $offset, $length, $encoding); }
+        function iconv_substr(string $string, int $offset, ?int $length = null, ?string $encoding = null): string|false { return p\Iconv::iconv_substr((string) $string, (string) $offset, $length, $encoding); }
     }
     if (!function_exists('iconv_mime_decode')) {
-        function iconv_mime_decode(?string $string, ?int $mode = 0, ?string $encoding = null): string|false { return p\Iconv::iconv_mime_decode((string) $string, (int) $mode, $encoding); }
+        function iconv_mime_decode(string $string, int $mode = 0, ?string $encoding = null): string|false { return p\Iconv::iconv_mime_decode((string) $string, (int) $mode, $encoding); }
     }
 }
diff --git a/src/Util/TestListenerTrait.php b/src/Util/TestListenerTrait.php
index 3b87d426d..56a8c2846 100644
--- a/src/Util/TestListenerTrait.php
+++ b/src/Util/TestListenerTrait.php
@@ -124,7 +124,6 @@ function {$f['name']}{$f['signature']}
                     $polyfillSignature = ReflectionCaster::getSignature($polyfillSignature);
 
                     $map = [
-                        '?' => '',
                         'IDNA_DEFAULT' => \PHP_VERSION_ID >= 80100 ? 'IDNA_DEFAULT' : '0',
                         'array|string|null $string' => 'array|string $string',
                         'array|string|null $from_encoding = null' => 'array|string|null $from_encoding = null',