[PHP-BUG] Bug #77112 [NEW]: tested on PHP >= 7.2.4

From:             php at pawlowicz dot it
Operating system: all
PHP version:      7.2.11
Package:          PHP Language Specification
Bug Type:         Bug
Bug description:tested on PHP >= 7.2.4

Description:
------------
Substr returns "" on string_length + 1 instead of "false"

Test script:
---------------
<?php

var_dump(substr("test", 3));  // "t" in PHP 5,  "t" in PHP 7.*
var_dump(substr("test1", 4));  // "1" in PHP 5,  "1" in PHP 7.*

// BUG START!!
var_dump(substr("test", 4));  // false in PHP 5,  "" in PHP 7.*
var_dump(substr("test1", 5));  // false in PHP 5,  "" in PHP 7.*
// BUG END

var_dump(substr("test", 5));  // false in PHP 5,  false in PHP 7.* 
var_dump(substr("test1", 6));  // false in PHP 5,  false in PHP 7.*


Expected result:
----------------
var_dump(substr("test", 4));  // false
var_dump(substr("test1", 5));  // false

Actual result:
--------------
var_dump(substr("test", 4));  // "" in PHP 7.*
var_dump(substr("test1", 5));  // "" in PHP 7.*

-- 
Edit bug report at https://bugs.php.net/bug.php?id=77112&edit=1
-- 
Try a snapshot (PHP 5.4):   https://bugs.php.net/fix.php?id=77112&r=trysnapshot54
Try a snapshot (PHP 5.5):   https://bugs.php.net/fix.php?id=77112&r=trysnapshot55
Try a snapshot (trunk):     https://bugs.php.net/fix.php?id=77112&r=trysnapshottrunk
Fixed in SVN:               https://bugs.php.net/fix.php?id=77112&r=fixed
Fixed in release:           https://bugs.php.net/fix.php?id=77112&r=alreadyfixed
Need backtrace:             https://bugs.php.net/fix.php?id=77112&r=needtrace
Need Reproduce Script:      https://bugs.php.net/fix.php?id=77112&r=needscript
Try newer version:          https://bugs.php.net/fix.php?id=77112&r=oldversion
Not developer issue:        https://bugs.php.net/fix.php?id=77112&r=support
Expected behavior:          https://bugs.php.net/fix.php?id=77112&r=notwrong
Not enough info:            https://bugs.php.net/fix.php?id=77112&r=notenoughinfo
Submitted twice:            https://bugs.php.net/fix.php?id=77112&r=submittedtwice
register_globals:           https://bugs.php.net/fix.php?id=77112&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=77112&r=php4
Daylight Savings:           https://bugs.php.net/fix.php?id=77112&r=dst
IIS Stability:              https://bugs.php.net/fix.php?id=77112&r=isapi
Install GNU Sed:            https://bugs.php.net/fix.php?id=77112&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=77112&r=float
No Zend Extensions:         https://bugs.php.net/fix.php?id=77112&r=nozend
MySQL Configuration Error:  https://bugs.php.net/fix.php?id=77112&r=mysqlcfg