title: PHP is Missing mysql pdo Driver
body: <p>I'm trying to run a Symfony 3 app with php 7 installed from source and I'm getting a Missing PDO driver exception.  According to <a href="http://pecl.php.net/package/PDO_MYSQL" rel="nofollow">http://pecl.php.net/package/PDO_MYSQL</a> the PDO_MYSQL extension is now part of PHP core.</p>
  
  <p>Q1.a) If I have the PDO_MYSQL extension (which I must, since its core)  does that mean that I also have the mysql pdo driver? </p>
  
  <p>Q2.b) Is there further runtime configuration I have to do to make sure that the driver gets used?  </p>
  
  <p>I've tried adding</p>
  
  <p>extension=php_pdo.so</p>
  
  <p>extension=php_pdo_mysql.so</p>
  
  <p>to my loaded php.ini file. </p>
  
  <p>Q2.a) Are these the correct extension names?  How could I find out?<br>
  Q2.b)Do I even have to provide extension references for core php elements?  </p>
  
  <p>Finally:</p>
  
  <p>Q3. How can I check whether my PHP install included the mysql pdo driver and how do I make sure that it is being loaded at runtime?</p>
  
  <p>Thanks for your input.</p>
  
  <p>Edit 1: I'm running on Linux Mint.<br>
  Edit 2: Here are a couple more details on what I'm seeing on my end:  </p>
  
  <p>"On starting up the built in php server I get the following message:
  PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/local/lib/php/extensions/no-debug-non-zts-20151012/php_pdo.so' - /usr/local/lib/php/extensions/no-debug-non-zts-20151012/php_pdo.so: cannot open shared object file: No such file or directory in Unknown on line 0
  PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/local/lib/php/extensions/no-debug-non-zts-20151012/php_pdo_mysql.so' - /usr/local/lib/php/extensions/no-debug-non-zts-20151012/php_pdo_mysql.so: cannot open shared object file: No such file or directory in Unknown on line 0"  </p>
  
  <p>This message suggests to me that either the extension references are incorrect or the extension does not exist.  I used "dpkg -L php-mysql" and found that the package was installed in "/usr/share/doc/php-mysql" however, when I check in the php-mysql directory, all I see is a changelog and a copyright file (with hiddens shown).  Is this the true install location of the package and, if so, should there be more in this directory?</p>