LINQ queries that perform arithmetic inside a C# checked { } block fail with ExpressionNotSupportedException.

CSHARP-5606 added support for ExpressionType.ConvertChecked but did not cover the checked arithmetic node kinds the compiler also emits in a checked context: AddChecked, SubtractChecked, MultiplyChecked, and NegateChecked. These are equivalent to their unchecked siblings for translation purposes (MongoDB has no overflow-checked arithmetic operators), so each should translate identically to Add / Subtract / Multiply / Negate.

  var collection = database.GetCollection<C>("c");
  Expression<Func<C, R>> projection;
  checked
  {
      projection = x => new R { V = x.A + x.B };
  }
  var query = collection.AsQueryable().Select(projection);
  var stages = query.ToString(); // or .ToList() 

Expected: translates to { $project : { V :

, _id : 0 } } — identical to the unchecked form.

Actual: throws MongoDB.Driver.Linq.ExpressionNotSupportedException : Expression not supported: (x.A + x.B).

Same failure occurs for , *, unary -, and enum +/ when written inside a checked block, in both Select/$project projections and Where/$match predicates.