Wikimedia Developer Support

How to deal with php APCu extension installation


I’m currently trying to setup up the mediawiki project on my system and i’m working with the mediawiki installation guide for XAMPP (I’m using an ubuntu 16.04 OS).

During my mediawiki installation, i got the warning that APCu is not installed. Then I downloaded APC-3.1.13 tar file and unzipped it, then went into the directory ran the following commands:

  • /opt/lampp/bin/phpize
  • ./config
  • make

running the make command returned an error and terminated the compilation:

/home/prosper/Downloads/APC-3.1.13/apc.c:47:43: fatal error: ext/standard/php_smart_str.h: No such file or directory
compilation terminated.
Makefile:195: recipe for target 'apc.lo' failed
make: *** [apc.lo] Error 1

Please i’d really appreciate ideas on how can i resolve this issue and continue my wikimedia installation.


Note that APC and APCu are two different things!. APC is no longer supported by PHP

APCu package is on


Also typically you can install it with the package manager of your OS. apt install php-apcu or something like that.


Thanks for distinguishing the two, i initially thought they were the same thing


I already used used php PEAR to install APCu the installation was successful but my mediawiki installer is yet to detect it.

I have a Xampp installed and also separately installed php7. I have two php installation one from Xampp and the other from the separate php7 installation.

Could this be the issue?


Possibly you installed it for one PHP version but not the other. Or for CLI mode but not for web mode (those have different config files in PHP, can cause confusion).

Typically the first step to debug this is to create a file with <?php phpinfo() ?> in MediaWiki root, open it in the browser, and that will show whether APCu is loaded, whether it is enabled, which settings files are used etc.


:smiley: Thanks for the support @Tgr and @Ciencia-Al-Poder

I was able to Completely install and configure MediaWiki on my PC.

@Tgr using sudo apt-get install php-apcu is pretty straight forward. I had to remove my previous PHP and XAMPP installation, then i reinstalled LAMPP server using tasksel and everything was pretty straight forward from there.

It’s quite easy, maybe my issue was New-Comer inertia, but it’s well now :grinning: