We are getting this error and related stack dump when store procedure is trying to call a aggregation function defined in a CLR assembly "myExtention"
2014-05-19 03:05:30.45 spid76 **Dump thread - spid = 0, EC = 0x00000001213C60F0
2014-05-19 03:05:30.45 spid76 *
2014-05-19 03:05:30.45 spid76 * User initiated stack dump. This is not a server exception dump.
2014-05-19 03:05:30.45 spid76 *
2014-05-19 03:05:30.45 spid76 ***Stack Dump being sent to D:\MSSQL\MSSQL10_50.MSSQLSERVER\MSSQL\LOG\SQLDump0003.txt
2014-05-19 03:05:30.45 spid76 * *******************************************************************************
2014-05-19 03:05:30.45 spid76 *
2014-05-19 03:05:30.45 spid76 * BEGIN STACK DUMP:
2014-05-19 03:05:30.45 spid76 * 05/19/14 03:05:30 spid 76
2014-05-19 03:05:30.45 spid76 *
2014-05-19 03:05:30.45 spid76 * FIRST OCCURRENCE: Common Language Runtime escalation on critical resource.
select * from sys.assemblies
nameprincipal_idassembly_idclr_namepermission_setpermission_set_descis_visiblecreate_datemodify_dateis_user_defined
------
Microsoft.SqlServer.Types41microsoft.sqlserver.types, version=10.0.0.0, culture=neutral, publickeytoken=89845dcd8080cc91, processorarchitecture=msil3UNSAFE_ACCESS12011-07-05 17:42:42.9032011-07-05 17:42:43.0170
myExtension1
65543myextension, version=0.0.0.0, culture=neutral, publickeytoken=null, processorarchitecture=msil1SAFE_ACCESS12014-05-06 17:13:05.5472014-05-06 17:13:05.5471