php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #45904 extends from a class which is extends from another cause executor failed
Submitted: 2008-08-24 18:33 UTC Modified: 2008-08-25 09:13 UTC
From: laruence at yahoo dot com dot cn Assigned:
Status: Not a bug Package: Scripting Engine problem
PHP Version: 5.2.6 OS: rhel-4.x
Private report: No CVE-ID: None
 [2008-08-24 18:33 UTC] laruence at yahoo dot com dot cn
Description:
------------
I found when I extends from a class which is also extended from a class cause the complie failed .

the parsing process:
starr:
    top_statement_list
;

top_statement_list:
        top_statement_list 
.... //有省略
;

top_statement:
.... //有省略
    |   class_declaration_statement   
 .... //有省略
;

class_declaration_statement:
        unticked_class_declaration_statement 
;

unticked_class_declaration_statement:
        class_entry_type T_STRING extends_from
.... //有省略
;

class_entry_type:
        T_CLASS
.... //有省略
;

extends_from:
        /* empty */   
    |   T_EXTENDS fully_qualified_class_name
.... //有省略
;
fully_qualified_class_name:
        T_STRING { zend_do_fetch_class(&$$, &$1 TSRMLS_CC); }
;

but if class with named fully_qualified_class_name is also a inherited
class , it cause executor failed.

  after I tracing the parser, I found the reason maybe:

  when opcode ZEND_FETCH_CLASS(op2 is b) which is used to generated class  a was executed.  the class b was not in the class table yet, because  class b is a drived class too ,it also  need
ZEND_DECLARE_INHERITED_CLASS belong to its to be executed for add itself to class_table.

so ,I think this should be a bug, am I wrong?



Reproduce code:
---------------
<?php
class a extends b {
};
class b extends c{
};
class c{
};
?>

Expected result:
----------------
PHP Fatal error:  Class 'b' not found in /home/xinchen/1.php on line 2
Fatal error: Class 'b' not found in /home/xinchen/1.php on line 2


Actual result:
--------------
http://www.laruence.com/2008/08/24/427.html

Patches

Add a Patch

Pull Requests

Add a Pull Request

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2008-08-25 03:50 UTC] laruence at yahoo dot com dot cn
sorry , but I found that the realy  reson is:

top_statement:
        statement
 ...
    |   class_declaration_statement     { zend_do_early_binding(TSRMLS_C); }
...
;

while the :
             void zend_do_early_binding(TSRMLS_D){
...
...
                    if (zend_lookup_class(Z_STRVAL_P(parent_name), Z_STRLEN_P(parent_name), &pce TSR
MLS_CC) == FAILURE) {
                        return;
                    }
...
...

}

so, early_binding couldn't add the class a in to class_table ,because the class b is also a drived class and its parent class c is defined  last in the script , so when zend_do_early_binding processing class b declaration, it will not be able to find class c in class_table .

so the ZE delay the process until executing process ,  while the declaration of class a is on the same way .

I think this must be the really reason ...

;)
 [2008-08-25 09:13 UTC] tularis@php.net
Please do not submit the same bug more than once. An existing
bug report already describes this very problem. Even if you feel
that your issue is somewhat different, the resolution is likely
to be the same. 

Thank you for your interest in PHP.

Duplicate of bug #45903
 
PHP Copyright © 2001-2024 The PHP Group
All rights reserved.
Last updated: Fri Mar 29 09:01:28 2024 UTC