By: Greg Pfeil <greg@technomadic.org>
Report compile error, don’t panic
GHC has no reason to expect an `ErrorCall` from a Core pass, so it caught it as
an internal failure and printed
panic! (the 'impossible' happened)
GHC version 9.10.3:
encountered recursion, which has been disabled:
followed by an invitation to report a GHC bug. This now reports an error
correctly.
The message itself is unchanged. Clears all four failures the previous commit
landed.