Keep getting OutOfMemoryException when doing a mapping

[zheg]

Keep getting System.OutOfMemoryException when doing a mapping.
A similar issue: #1999

Version 7.0.1

First time:
System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
at System.Runtime.CompilerServices.RuntimeHelpers._CompileMethod(IRuntimeMethodInfo method)
at System.Reflection.Emit.DynamicMethod.CreateDelegate(Type delegateType, Object target)
at System.Linq.Expressions.Compiler.LambdaCompiler.Compile(LambdaExpression lambda, DebugInfoGenerator debugInfoGenerator)
at AutoMapper.MapperConfiguration.CreateMapperFuncs(MapRequest mapRequest)
at AutoMapper.LockingConcurrentDictionary2.<>c__DisplayClass2_1.<.ctor>b__1() at System.Lazy1.CreateValue()
at System.Lazy`1.LazyInitValue()
at AutoMapper.MapperConfiguration.GetMapperFunc[TSource,TDestination](MapRequest mapRequest)
at AutoMapper.MapperConfiguration.GetMapperFunc[TSource,TDestination](TypePair types, PropertyMap propertyMap)
at AutoMapper.Mapper.AutoMapper.IMapper.Map[TSource,TDestination](TSource source)

Keep getting this after even when the memory is not high:
System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
at System.Runtime.CompilerServices.RuntimeHelpers._CompileMethod(IRuntimeMethodInfo method)
at System.Reflection.Emit.DynamicMethod.CreateDelegate(Type delegateType, Object target)
at System.Linq.Expressions.Compiler.LambdaCompiler.Compile(LambdaExpression lambda, DebugInfoGenerator debugInfoGenerator)
at AutoMapper.MapperConfiguration.CreateMapperFuncs(MapRequest mapRequest)
at AutoMapper.LockingConcurrentDictionary2.<>c__DisplayClass2_1.<.ctor>b__1() at System.Lazy1.CreateValue()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Lazy`1.get_Value()
at AutoMapper.MapperConfiguration.GetMapperFunc[TSource,TDestination](MapRequest mapRequest)
at AutoMapper.MapperConfiguration.GetMapperFunc[TSource,TDestination](TypePair types, PropertyMap propertyMap)
at AutoMapper.Mapper.AutoMapper.IMapper.Map[TSource,TDestination](TSource source)

[lbargaoanu]

Upgrade! Other than that, a repro would help. Make a gist that we can execute and see fail.