ghci-iserv is broken

[blackgnezdo]

% ghci -fexternal-interpreter                                                                                                                           
GHCi, version 8.10.1: https://www.haskell.org/ghc/  :? for help
Loaded GHCi configuration from /home/greg/.ghci
Prelude
> ghc-iserv: internal error: evacuate: strange closure type 400513752
    (GHC version 8.10.1 for x86_64_unknown_openbsd)
    Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug

[blackgnezdo]

This breaks some 300 tests from ghc tests suite.