compiler crash with (phantom type + extensible record + type alias)

[rlefevre]

The following SSCCE always leads to Map.!: given key is not an element in the map with Elm 0.19.0, even without the --debug option, and from a clean cache and elm-stuff state:

module Sscce exposing (bug)


type Value r
    = Value


type alias Bug r =
    Value { r | field : () } -> ()


bug : Bug {}
bug Value =
    ()

Example from a clean state:

$ elm make Sscce.elm
Starting downloads...

  ● elm/time 1.0.0
  ● elm/core 1.0.2
  ● elm/url 1.0.0
  ● elm/virtual-dom 1.0.2
  ● elm/html 1.0.0
  ● elm/json 1.1.3
  ● elm/browser 1.0.1

Dependencies ready!
elm: Map.!: given key is not an element in the map
CallStack (from HasCallStack):
  error, called at ./Data/Map/Internal.hs:610:17 in containers-0.5.11.0-K2TDqgYtGUcKxAY1UqVZ3R:Data.Map.Internal

Building again does not solve the issue.