title: Warning: PHP Startup: Unable to load dynamic library apc.so
body: <p>I case, I tried to install <code>APC</code>.
  I run <code>configure</code> file it's running normally, but when I try to <code>make</code> I get the following errors :</p>
  
  <pre><code>/home/ghost/APC-3.1.13/apc_cache.c: In function ‘_apc_cache_user_update’:
  /home/ghost/APC-3.1.13/apc_cache.c:818:63: error: ‘IS_CONSTANT_INDEX’ undeclared (first use in this function)
           switch(Z_TYPE_P((*slot)-&gt;value-&gt;data.user.val) &amp; ~IS_CONSTANT_INDEX
                                                             ^
  /home/ghost/APC-3.1.13/apc_cache.c:818:63: note: each undeclared identifier is reported only once for each function it appears in
  /home/ghost/APC-3.1.13/apc_cache.c:820:22: error: ‘IS_CONSTANT_ARRAY’ undeclared (first use in this function)
               case IS_CONSTANT_ARRAY:
                    ^
  Makefile:186: recipe for target 'apc_cache.lo' failed
  make: *** [apc_cache.lo] Error 1
  </code></pre>
  
  <p>After that</p>
  
  <p>I run this command <code>sh -c "echo 'extension=apc.so' &gt;&gt; /opt/lampp/etc/php.ini"</code></p>
  
  <p>Check if APC installed</p>
  
  <p><code>/opt/lampp/bin/php -r 'echo phpinfo()' | grep apc --color</code></p>
  
  <p>Output :</p>
  
  <pre><code>Warning: PHP Startup: Unable to load dynamic library '/opt/lampp/lib/php/extensions/no-debug-non-zts-20131226/apc.so' - /opt/lampp/lib/php/extensions/no-debug-non-zts-20131226/apc.so: cannot open shared object file: No such file or directory in Unknown on line 0
  </code></pre>
  
  <p>How do I fix it ?</p>