If you use Extended Events you may have noticed that the ERRORLOG file gets bloated with messages like:
Using ‘dbghelp.dll’ version ’4.0.5′
every time you query sys.dm_xe_sessions or read a file using Transact-SQL and the sys.fn_xe_file_target_read_file() table-valued function. This issue can be especially problematic on SharePoint 2013 installations, where a timer job queries Extended Events every 15 seconds to monitor the SharePoint SQL Server instance.
This has been fixed in SQL Server 2012 SP1 + CU6 which was just released today (https://support.microsoft.com/kb/2878139). The specifics of this “feature” are contained in the following KB article (https://support.microsoft.com/kb/2878139).