armv7 ghc-8.6.5 panics while building Agda-2.6.0.1: "piResultTys1 TyCon [ProblemId]"

Summary

[157 of 357] Compiling Agda.TypeChecking.Monad.Base ( src/full/Agda/TypeChecking/Monad/Base.hs, dist/build/Agda/TypeChecking/Monad/Base.o )
BUILDSTDERR: ghc: panic! (the 'impossible' happened)
BUILDSTDERR:   (GHC version 8.6.5 for arm-unknown-linux):
BUILDSTDERR: 	piResultTys1
BUILDSTDERR:   TyCon
BUILDSTDERR:   [ProblemId]
BUILDSTDERR:   Call stack:
BUILDSTDERR:       CallStack (from HasCallStack):
BUILDSTDERR:         callStackDoc, called at compiler/utils/Outputable.hs:1160:37 in ghc:Outputable
BUILDSTDERR:         pprPanic, called at compiler/types/Type.hs:1022:5 in ghc:Type
BUILDSTDERR: Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

Steps to reproduce

Build latest Agda-2.6.0.1 with armv7 ghc-8.6.5, eg on Fedora 31 (development release).

Environment

• GHC version used: 8.6.5

Optional:

• Operating System: Fedora 31
• System Architecture: armv7