Warnings are logged in to var report in magento 2

Question

We are using Magento ver. 2.1.3, when browsing website, error report is generated with full of warnings and website is halted with Error log records.

1. I have added below code in Index.php but not working.

   error_reporting(E_ERROR | E_PARSE);
   

2. These warnings are from core modules for example

Warning: array_merge(): Argument #2 is not an array in vendor\magento\module-page-cache\Model\Layout\LayoutPlugin.php on line 71

3. If we solve one, then it is logged with new one.

4. Can any one suggest me how can i solve this ?

5. How the core code does exists with warnings ?

Answer 1

The Magento error handler converts warnings into exceptions:

https://github.com/magento/magento2/blob/2.1/lib/internal/Magento/Framework/App/ErrorHandler.php

But as you can seee in this code, it respects the error reporting settings. So your setting in index.php does not take effect.

That is because Magento sets it to E_ALL in https://github.com/magento/magento2/blob/2.1/app/bootstrap.php#L10

You try to adjust it there, but the right way to go really is to fix the warnings. They tell you that something is wrong.