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Summary

Trying to reify fields from a record defined with DuplicateRecordFields extension leads to a confusing error message:

Exp.hs:11:1: error:
    Ambiguous occurrence ‘Exp.foo’
    It could refer to
       either the field ‘foo’, defined at Exp.hs:9:18
           or the field ‘foo’, defined at Exp.hs:8:18

Even if the name itself is not present in spliced code.

Steps to reproduce

Complete code snippet is here: https://gist.github.com/maksbotan/146b250ad295c0f5896a2313ce918cd0

Briefly:

• Write TemplateHaskell function of type Name -> Q [Dec], where Name is supposed to refer to a data type.
• reify the Name to get RecC info with Names of the
• call reify on those Names to get their types

make :: Name -> Q [Dec]
make name = do
  TyConI (DataD _ _ _ _ [RecC con fields'] _) <- reify name
  let fields = [ field | (field, _, _) <- fields' ]
  fieldInfos <- mapM reify fields

  return []

When the record in question is defined in a file with DuplicateRecordFields and really has duplicate fields, GHC will emit a compilation error with confusing message.

Expected behavior

Since I reifyed concrete record type, I expect to be able to extras its fields without any ambiguity.

Environment

• GHC version used: 8.6.3 (Stack LTS-13.6), 8.6.5 (nix), 8.8.1 (nix)
• Operating System: macOS mojave

This looks related to #14848 and #17381, but in my case I don't do any quasiquoting. Another difference is that in my case the error message is really misleading.