Bad error message under DisambiguateRecordFields

Summary

DisambiguateRecordFields can still give some unexpected errors about (un)ambiguous record fields in the presence of other errors.

Steps to reproduce

Compiling this:

{-# LANGUAGE DisambiguateRecordFields #-}

data A = A { sum :: Int }
data B = B

myA = B { sum = 0 }

Produces the error:

T2.hs:6:11: error:
    Ambiguous occurrence ‘sum’
    It could refer to
       either ‘Prelude.sum’,
              imported from ‘Prelude’ at T2.hs:1:1
              (and originally defined in ‘Data.Foldable’)
           or the field ‘sum’, defined at T2.hs:3:13
  |
6 | myA = B { sum = 0 }
  |           ^^^

Note that this only works for names that are already defined in imported modules. That's why I chose the name sum.

Expected behavior

I expect to see the error that would happen if you remove the data A declaration, namely:

T2.hs:6:7: error:
    • Constructor ‘B’ does not have field ‘sum’
    • In the expression: B {sum = 0}
      In an equation for ‘myA’: myA = B {sum = 0}
  |
6 | myA = B { sum = 0 }
  |       ^^^^^^^^^^^^^

Environment

• GHC version used: 8.10.7