Bug #77557 [NEW]: mb_regex_replace does not handle backreferences if regex-encoding is UTF-32

From: codes at designsandcodes dot com Operating system: Windows 10, Ubuntu 16.04 PHP version: 7.3.1 Package: mbstring related Bug Type: Bug Bug description:mb_regex_replace does not handle backreferences if regex-encoding is UTF-32 Description: ------------ Per summary, backreferences are not properly replaced if the regex encoding is any of the UTF-32 flavors (BE, LE, UCS-4). All 3 parameters (pattern, replace, subject) are being presented in the correct UTF-32 flavor; replace is being returned unmodified. Test script: --------------- $regexEncoding = 'UTF-32'; mb_regex_encoding( $regexEncoding ); var_export( mb_ereg_replace( mb_convert_encoding( '.+', $regexEncoding ), mb_convert_encoding( "the \\0", $regexEncoding ), mb_convert_encoding( 'dog', $regexEncoding ) ) ); Expected result: ---------------- '' . "\0" . '' . "\0" . '' . "\0" . 't' . "\0" . '' . "\0" . '' . "\0" . 'h' . "\0" . '' . "\0" . '' . "\0" . 'e' . "\0" . '' . "\0" . '' . "\0" . ' ' . "\0" . '' . "\0" . '' . "\0" . 'd' . "\0" . '' . "\0" . '' . "\0" . 'o' . "\0" . '' . "\0" . '' . "\0" . 'g' e.g., "the dog" in UTF-32 encoding Actual result: -------------- '' . "\0" . '' . "\0" . '' . "\0" . 't' . "\0" . '' . "\0" . '' . "\0" . 'h' . "\0" . '' . "\0" . '' . "\0" . 'e' . "\0" . '' . "\0" . '' . "\0" . ' ' . "\0" . '' . "\0" . '' . "\0" . '\\' . "\0" . '' . "\0" . '' . "\0" . '0' e.g., "\\0" in UTF-32 encoding -- Edit bug report at https://bugs.php.net/bug.php?id=77557&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=77557&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=77557&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=77557&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=77557&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=77557&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=77557&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=77557&r=needscript Try newer version: https://bugs.php.net/fix.php?id=77557&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=77557&r=support Expected behavior: https://bugs.php.net/fix.php?id=77557&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=77557&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=77557&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=77557&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=77557&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=77557&r=dst IIS Stability: https://bugs.php.net/fix.php?id=77557&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=77557&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=77557&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=77557&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=77557&r=mysqlcfg