Unable to update modules due to Archive_Tar incompatibility with PHP 7.2

I have just come across this issue on a recently update website of mine.

How do I fix it? - do I need to wait for a core update?

Is this reproducible in Drupal 8 also? It looks like the same code: https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Archiver%...

It may be very simple to patch (see https://github.com/pear/Archive_Tar/pull/18), and then upgrading to a newer version of Archive_Tar could be discussed in a separate followup issue.

Had this problem while trying to backup and migrate using the eponymous module.
Modified the system.tar.inc file accordingly to the new version 1.4.3.
This solved the issue for me, as I hope it does for you.

also get error when try to update Modules:

Ett AJAX HTTP-fel inträffade Resultatkod för HTTP: 200 Felsökningsinformation följer. Sökväg: /batch?render=overlay&id=476&op=do Statustext: OK Svarstext: Fatal error: Cannot use result of built-in function in write context in /myDP_Core/modules/system/system.tar.inc on line 717.

This error is fully related to PHP 7.2 -
I will not patch my core! I will use php 7.1 instead, waiting for a ordinary fix. (Also Rules need to be updated for php 7.2 and probably more modules ?)

It would be grate if this could be fixed in next Core 7.59 version
We probably need a list on all modules who needs to be updated to be compatible with PHP 7.2. That's why I will use php 7.1 until right time comes.

Here's the very simple patch to fix this deprecation, based on upstream commit

Fixed patch line endings

@David_Rothstein (comment #4)
I have tried to reproduce this issue in Drupal 8 (using PHP 7.2). This fatal error does not occur in Drupal 8.
Somehow the fatal error only occurs when the result of a built-in function is referenced when not in a namespace.

Did some tests:

no namespace, Fatal error occurs in PHP 7.2: (test result at https://3v4l.org/XopHJ)

class Test {
    public function test() {
      $args = & func_get_args();
    }
}

code in namespace, No fatal error occurs in PHP 7.2: (testresult at https://3v4l.org/W16mN)

namespace Test {
  class Test {
      public function test() {
        $args = & func_get_args();
      }
  }
}

So I suppose this could be fixed by wrapping the code in a namespace or update the Archive_Tar class to the newest version (1.4.3). Since we do not use namespaces in Drupal 7, we should do the latter.

Just manually tested the updated class and the fatal error no longer occurs in PHP 7.2

Added patch which contains updates of PEAR.php (1.9.5 -> 1.10.5) and Archive Tar class (1.4.0 -> 1.4.3).

aside from minor code style, this is RTBC

we've combined this latest patch above with the two other patches for php 7.2
all passing, 100% pass for php 7.2 on D7 core, WOOT

#2947772: Fully support PHP 7.2 in Drupal 7

Looks good to me and I think it is okay to upgrade the version directly as the code is simple enough: This is pending commit.

tar module installation gives the error "Fatal error: Cannot use result of built-in function in write context in \modules\system\system.tar.inc on line 717 drupal"
but zip format modules install fine in my drupal 7.59

Committed and pushed to 7.x. Thanks all!

Thanks! This was really helpful and allowed the system to work properly.

I'm running on drupal 7.6 and getting this error as well when upgrading to php 7.2
The patch on #8 fixed the issue

short term you can upgrade to 7.x dev release , no need for patching on 7.x dev.