Compiler panic when compiling Cabal with 8.10.1 and `dno-typeable-binds`
I wondered about the cost of Typeable
(see #13261) bindings on real world code so wanted to do
the "Cabal test" (compiling cabal the library).
However this surprisingly triggered a panic instead.
Andi@___ MINGW64 ~/cabal-head/Cabal
$ ghc -O Setup.hs -fforce-recomp -dno-typeable-binds +RTS -s
[ 1 of 242] Compiling Distribution.Compat.Async ( Distribution\Compat\Async.hs, Distribution\Compat\Async.o )
GHC error in desugarer lookup in Distribution.Compat.Async:
attempting to use module `main:Distribution.Compat.Async' (.\Distribution\Compat\Async.hs) which is not loaded
ghc.exe: panic! (the 'impossible' happened)
(GHC version 8.10.1:
initDs
Please report this as a GHC bug: https://www.haskell.org/ghc/reportabug
750,182,440 bytes allocated in the heap
89,913,368 bytes copied during GC
24,635,776 bytes maximum residency (8 sample(s))
857,728 bytes maximum slop
49 MiB total memory in use (0 MB lost due to fragmentation)
Tot time (elapsed) Avg pause Max pause
Gen 0 308 colls, 0 par 0.094s 0.061s 0.0002s 0.0082s
Gen 1 8 colls, 0 par 0.062s 0.090s 0.0112s 0.0231s
TASKS: 5 (1 bound, 4 peak workers (4 total), using -N1)
SPARKS: 0 (0 converted, 0 overflowed, 0 dud, 0 GC'd, 0 fizzled)
INIT time 0.000s ( 0.000s elapsed)
MUT time 0.281s ( 2.163s elapsed)
GC time 0.156s ( 0.151s elapsed)
EXIT time 0.000s ( 0.000s elapsed)
Total time 0.438s ( 2.314s elapsed)
Alloc rate 2,667,315,342 bytes per MUT second
Productivity 64.3% of total user, 93.5% of total elapsed