[wp-trac] [WordPress Trac] #18525: zlib.output_compression "on" in server conflicts with autoupdate

[WordPress Trac]

#18525: zlib.output_compression "on" in server conflicts with autoupdate
------------------------------------+------------------------------
 Reporter:  avidre                  |       Owner:  (none)
     Type:  defect (bug)            |      Status:  reopened
 Priority:  normal                  |   Milestone:  Awaiting Review
Component:  Bootstrap/Load          |     Version:  3.2.1
 Severity:  normal                  |  Resolution:
 Keywords:  has-patch dev-feedback  |     Focuses:
------------------------------------+------------------------------

Comment (by tradesouthwest@…):

 Would like to report the same errors in 5.2.4 with PHP 7.2.21 and 7.3.9,
 Apache 2.4.41, 5.5.62-cll, 2.6.32-954.3.5.lve1.4.61.el6.x86_64.

 `Notice: ob_end_flush(): failed to send buffer of zlib output compression
 (0) in /home/fencedir/plus.unitizr.com/wp-includes/functions.php on line
 4344" `

 Error occurs with on all public side and Admin pages **with _every_ plugin
 disabled** and with any plugin enabled; no mu-plugins used. And _only_
 with WP_DEBUG true<sup>1</sup>

 `remove_action( 'shutdown', 'wp_ob_end_flush_all', 1 );` Has no effect

 {{{#!php
 <?php
 function wp_ob_end_flush_all_fixed() {
         $start = (int) ini_get('zlib.output_compression');
         $levels = ob_get_level();
         for ( $i = $start; $i < $levels; $i++ ) {
                 ob_end_flush();
         }
 }
 remove_action('shutdown', 'wp_ob_end_flush_all', 1);
 add_action('shutdown', 'wp_ob_end_flush_all_fixed', 1);
 }}}

 Does remove error!
 _(see)_ https://core.trac.wordpress.org/ticket/22430#comment:13
 (whitespace & comments removed)

 **Q.:**
 ''Any reason to think that a core update to check for the state of php.ini
 and maybe throw a dismissable warning, as apposed to an error that is
 derived from core file (functions.php)?''

 <sub>1</sub> I tend to agree with @gilmore_love in that there are plenty
 of reasons to fix this; mostly to help developers and to keep core WP
 clean. Granted not all server configs and not all PHP versions (as well as
 NewRelic and a ton of other server 'tools') can be supported but to
 reiterate; security is priority and spending time on this before spending
 time on changing WP components is most salient for the WP community.

-- 
Ticket URL: <https://core.trac.wordpress.org/ticket/18525#comment:31>
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