Description:
------------
set_error_handler truncate over 1024bytes data to 1023bytes

Reproduce code:
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ini_set('log_errors_max_len', 0);

set_error_handler('error_handler');
trigger_error(str_repeat('1', 1130));

function error_handler($code, $str, $file, $line) {
 echo strlen($str). "\n";
 exit();
}

Expected result:
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1130

Actual result:
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1023