Unable to remove backing field

[wizgob]

Our team is getting random errors during build: EXEC: Error XW0006 : Unable to remove backing field: type: MyType, property: MyProperty, field:

We are using Xtensive.Orm 6.0.11 with .net 4.7.2. We are also using Postsharp 2023.0.7

I've been able to attach te debugger to Xtensive.Orm.Weaver.dll: The issue seems to be that RemoveBackingFieldTask.GetBackingFieldName() is returning null.

private string GetBackingFieldName()
{
  foreach (var instruction in property.GetMethod.Body.Instructions) {
    if (instruction.OpCode.Code==Code.Ldfld) {
      var field = (FieldReference) instruction.Operand;
      return field.Name;
    }
  }
  return null;
}

The contents of property.GetMethod.Body.Instructions seems to indicate the assembly was already processed wy the weaver

Arguments file passed to the weaver:

/type:.csproj
/backup
/stamp
/pdb
/input:C:\code\Solution\MyProject\obj\Debug\MyProject.dll
[SNIP]

And MyProject.dll from obj\Debug contains the ProcessedByWeaver attribute:

This error is a problem for us because the workaround is to clean, the build again the solution which takes 8 minutes because we have a big solution.

I'm not able to reproduce it every time : this error appears randomly. I suspect something in the build process when doing a partial build of the solution is causing the weaver to get as an input an assembly that is already weaved.

Do you think adding a condition in the weaver do to nothing if the file is already weaved could be a solution?

I have saved the content of an obj folder just before the error and the command to launch the weaver : I can share them privately if needed.