Hi,

VLD is not a zend extension, so gets loaded/initialised later anyway. 
And it seems your hint with post_startup works. I'd appreciate if you 
could have a look at my change though:

https://github.com/xdebug/xdebug/commit/3ef3c63ffc831426a45439dbf8b56b998f84d5b1

cheers,
Derick

On Mon, 17 Dec 2018, Dmitry Stogov wrote:

> Hi Derick,
> 
> 
> First, check why VLD works out of the box.
> 
> At second, you may plug into post_startup hook to reassign zend_compile after 
> opcache.
> 
> 
> Thanks. Dmitry.
> 
> ________________________________
> From: Derick Rethans <der...@php.net>
> Sent: Saturday, December 15, 2018 10:01:37 PM
> To: Dmitry Stogov
> Cc: Nikita Popov; PHP Developers Mailing List
> Subject: Changes to when OPcache initialises
> 
> Hi!
> 
> I am working on making Xdebug work properly with PHP 7.3, and over the
> last week I have been tearing my hair out as to why Xdebug's view of
> opcodes was no longer showing the opcodes that OPcache had
> modified/optimised. In PHP 7.2, the order in which you load Xdebug and
> OPcache made a difference.
> 
> OPcache optimises out line 6, which has dead code:
> 
>   1 <?php
>   2
>   3 try
>   4 {
>   5     throw new Exception();
>   6     echo strlen( "Revenge is a dish best served cold.\n" );
>   7 }
>   8 catch(Exception $e)
>   9 {
>  10 }
>  11
>  12 echo strlen( "The fire is always hotter on someone elses face." ), "\n";
>  13 ?>
> 
> 
> derick@singlemalt:~/dev/php/derickr-xdebug $ /usr/local/php/7.2.13/bin/php  
> -n -dzend_extension=opcache.so  -d "zend_extension=xdebug.so" -d 
> "opcache.enable=1" -d "opcache.enable_cli=1" -d "xdebug.extended_info=1" 
> -dvld.active=1 -f 
> "/home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php"
> 48
> /home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php:7:
> array(4) {
>   [5] =>
>   int(1)
>   [8] =>
>   int(1)
>   [12] =>
>   int(1)
>   [14] =>
>   int(1)
> }
> 
> [GIT: issue1598-no-code-coverage-with-opcache][PHP: 7.2.13  ]
> derick@singlemalt:~/dev/php/derickr-xdebug $ /usr/local/php/7.2.13/bin/php  
> -n  -d "zend_extension=xdebug.so" -dzend_extension=opcache.so -d 
> "opcache.enable=1" -d "opcache.enable_cli=1" -d "xdebug.extended_info=1" 
> -dvld.active=1 -f 
> "/home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php"
> 48
> /home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php:7:
> array(5) {
>   [5] =>
>   int(1)
>   [6] =>
>   int(-2)
>   [8] =>
>   int(1)
>   [12] =>
>   int(1)
>   [14] =>
>   int(1)
> }
> 
> Where as with PHP 7.3.0, they both show the *unoptimised* version:
> 
> derick@singlemalt:~/dev/php/derickr-xdebug $ /usr/local/php/7.3.0/bin/php  -n 
> -dzend_extension=opcache.so  -d "zend_extension=xdebug.so" -d 
> "opcache.enable=1" -d "opcache.enable_cli=1" -d "xdebug.extended_info=1" 
> -dvld.active=1 -f 
> "/home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php"
> 48
> /home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php:7:
> array(5) {
>   [5] =>
>   int(1)
>   [6] =>
>   int(-2)
>   [8] =>
>   int(1)
>   [12] =>
>   int(1)
>   [14] =>
>   int(1)
> }
> [GIT: issue1598-no-code-coverage-with-opcache][PHP: 7.2.13  ]
> derick@singlemalt:~/dev/php/derickr-xdebug $ /usr/local/php/7.3.0/bin/php  -n 
>  -d "zend_extension=xdebug.so" -dzend_extension=opcache.so -d 
> "opcache.enable=1" -d "opcache.enable_cli=1" -d "xdebug.extended_info=1" 
> -dvld.active=1 -f 
> "/home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php"
> 48
> /home/derick/dev/php/derickr-xdebug/tests/bug00213-php73-opcache.php:7:
> array(5) {
>   [5] =>
>   int(1)
>   [6] =>
>   int(-2)
>   [8] =>
>   int(1)
>   [12] =>
>   int(1)
>   [14] =>
>   int(1)
> }
> 
> Curiously, vld, would always show the right (optimised) opcodes:
> 
> filename:       /home/derick/dev/php/derickr-xdebug/tests/bug00213.inc
> function name:  (null)
> number of ops:  12
> compiled vars:  !0 = $e
> line     #* E I O op                           fetch          ext  return  
> operands
> -------------------------------------------------------------------------------------
>    5     0  E >   EXT_STMT
>          1        NEW                                              $1      :-5
>          2        EXT_FCALL_BEGIN
>          3        DO_FCALL                                      0
>          4        EXT_FCALL_END
>          5      > THROW                                         0          $1
>    8     6  E > > CATCH                                                    
> 'Exception', !0
>   12     7    >   EXT_STMT
>          8        ECHO                                                     48
>          9        EXT_STMT
>         10        ECHO                                                     
> '%0A'
>   14    11      > RETURN                                                   1
> 
> branch: #  0; line:     5-    5; sop:     0; eop:     5; out0:  -2
> branch: #  6; line:     8-    8; sop:     6; eop:     6; out0:   7; out1:  -2
> branch: #  7; line:    12-   14; sop:     7; eop:    11; out0:  -2
> path #1: 0,
> path #2: 6, 7,
> 
> 
> So I did some digging and found out that OPcache in PHP 7.3 has had a change
> to the loading order. This was done in:
> https://github.com/php/php-src/commit/b4903aef16ec215f2095ff0a3615524656401660:
> 
>         commit b4903aef16ec215f2095ff0a3615524656401660
>         Author: Dmitry Stogov <dmi...@zend.com>
>         Date:   Wed Oct 18 17:18:54 2017 +0300
> 
>                 Move a part of opcache initialization into post_startup phase 
> (when all extensions already loaded).
> 
> Both Xdebug and OPcache hook into zend_compile. In PHP 7.2, when as per
> documentation, OPcache was loaded after Xdebug, OPcache's zend_compile
> (accel_startup) was run *first*, so that Xdebug sees the optimised
> opcodes.
> 
> In PHP 7.3, after the above commit, Xdebug's zend_compile hook
> (xdebug_compile_file) is run before OPcache's — *no matter which
> extension is loaded first*. Due to this, Xdebug can not properly do code
> coverage anymore when OPcache is also present, as it can only see
> *unoptimised* oparrays during its zend_compile hook.
> 
> Because opcodes may now differ between when Xdebug analyses oparrays
> (zend_compile stage) and when it uses it (zend_execute stage) the
> results can be inconsistent in OPcache has optimised things away, and/or
> rearranged branches.
> 
> Right now, I don't think I have a choice but to disallow code coverage
> analysis when OPcache is present, but I would prefer finding a solution
> to this so that OPcache and Xdebug work together again, as it did for
> PHP versions before 7.3.
> 
> cheers,
> Derick
> 
> --
> https://derickrethans.nl | https://xdebug.org | https://dram.io
> Like Xdebug? Consider a donation: https://xdebug.org/donate.php,
> or become my Patron: https://www.patreon.com/derickr
> twitter: @derickr and @xdebug
> 

-- 
https://derickrethans.nl | https://xdebug.org | https://dram.io
Like Xdebug? Consider a donation: https://xdebug.org/donate.php,
or become my Patron: https://www.patreon.com/derickr
twitter: @derickr and @xdebug
-- 
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php

Reply via email to