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Query with lots of nullable columns create stack overflow

See original GitHub issue

I found this while working with a very, very wide table with lots of nullable columns. The code gen work fine however when it runs you get a stack overflow in the getItem:

Stack overflow.... 1872/2038 -
   at DbGen+Scripts+MenyColumns.getItem(Microsoft.Data.SqlClient.SqlDataReader)
   at DbGen+Scripts+ExecuteSingleAsync@12450-422.Invoke(Microsoft.Data.SqlClient.SqlDataReader)
   at DbGen+Scripts+ExecuteSingleAsync@12450-426.Invoke(Microsoft.Data.SqlClient.SqlDataReader)
   at Facil.Runtime.CSharp.GeneratedCodeUtils+<ExecuteQuerySingleAsync>d__8`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1+AsyncStateMachineBox`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e],[Facil.Runtime.CSharp.GeneratedCodeUtils+<ExecuteQuerySingleAsync>d__8`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]], Facil.Runtime.CSharp, Version=0.2.6.0, Culture=neutral, PublicKeyToken=null]].MoveNext(System.Threading.Thread)
   at System.Threading.Tasks.AwaitTaskContinuation.RunOrScheduleAction(System.Runtime.CompilerServices.IAsyncStateMachineBox, Boolean)
   at System.Threading.Tasks.Task.RunContinuations(System.Object)
   at System.Threading.Tasks.Task`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TrySetResult(System.__Canon)
   at System.Threading.Tasks.UnwrapPromise`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].TrySetFromTask(System.Threading.Tasks.Task, Boolean)
   at System.Threading.Tasks.UnwrapPromise`1[[System.__Canon, System.Private.CoreLib, Version=5.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].ProcessInnerTask(System.Threading.Tasks.Task)
   at System.Threading.Tasks.Task.RunContinuations(System.Object)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef, System.Threading.Thread)
   at System.Threading.ThreadPoolWorkQueue.Dispatch()

I have create a PR with a test that shows this error: https://github.com/cmeeren/Facil/pull/10

I have seen a similar problem when I ported some code over to dotnet core. I think the F# compiler does some function nesting which ticks over a magic stack allowance and throws the error. In my case it was expect computation expressions test which a restructured into a list.

Issue Analytics

State:
Created 3 years ago
Comments:19 (19 by maintainers)

Top GitHub Comments

1reaction

davidtmecommented, Feb 15, 2021

Also, do you know the approximate column number limit for when this started to occur?

It only happens with nullable columns as I think the extra if statements create the stack overflow

Do you know if this was specific to nullable columns?

It seems a but random but it somewhere between 394 to 400 columns but I don’t think that number could be relied upon as it could be depend on how far the call is in the stack?

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cmeerencommented, Apr 8, 2022

https://github.com/dotnet/fsharp/issues/11114 was reopened after I confirmed that it was in fact not fixed. However, there is little to do on my part except keep the workaround in place. So I don’t see any reason to reopen this issue.