CompileMappings NullReferenceException

[przemasd]

Hi,
after I upgraded your nuget to the 11.0.1 version I get a System.NullReferenceException when I try to Compile mappings.

the strange is that the same code working on 10.1.1 version correctly

Source/destination types

            builder.Register(ctx =>
            {
                var profiles = ctx.Resolve<Profile[]>();
                var configuration = new MapperConfiguration(cfg =>
                {
                    cfg.AddProfiles(profiles);
                    cfg.Internal().AllowAdditiveTypeMapCreation = true;
                    cfg.Internal().ForAllMaps((_, mapCfg) => mapCfg.PreserveReferences());
                });

                return configuration;
            }).SingleInstance();

            builder.Register(ctx =>
            {
                var configuration = ctx.Resolve<MapperConfiguration>();
                configuration.AssertConfigurationIsValid();
                configuration.CompileMappings();
                return configuration.CreateMapper();
            }).As<IMapper>();

The issue is throwing in internal of your method CompileExecutionPlan and does not return more of the "System.NullReferenceException: 'Object reference not set to an instance of an object.'" information.

 at AutoMapper.MapperConfiguration.CompileExecutionPlan(MapRequest mapRequest)
  at AutoMapper.Internal.LockingConcurrentDictionary`2.<>c__DisplayClass1_1.<.ctor>b__1()
  at System.Lazy`1.ViaFactory(LazyThreadSafetyMode mode)
  at System.Lazy`1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor)
  at System.Lazy`1.CreateValue()
  at AutoMapper.MapperConfiguration.CompileMappings()

What is interesting the VS debugger threw an exception of type 'System.NullReferenceException' for the first 5 elements of _resolvedMaps but when I call everyone one by one its ok

I am aware that this may be a bug in my code but I cannot figure out where it may be.
Some ideas on how to return un information on what mapping those issues is throwing?

[lbargaoanu]

Remove CompileMappings, solve the problem, and add it back again. The MapRequest parameter identifies the map.
Other than that, a repro would help. Make a gist that we can execute and see fail.

[lbargaoanu]

This code dump is not useful. You need to create a repro as requested.

[lbargaoanu]

Try the MyGet build.