Derived BitPack instance introduces Dubious primitive instantiation warning #2386
Description
The implementation for derived BitPack instances produces the following warning when producing HDL:
GHC: Setting up GHC took: 0.167s
GHC: Compiling and loading modules took: 0.088s
Clash: Parsing and compiling primitives took 0.143s
GHC+Clash: Loading modules cumulatively took 0.534s
Clash: Compiling Example.Project.topEntity
Clash: Normalization took 0.069s
[WARNING] Dubious primitive instantiation for GHC.Num.Integer.integerToInt#: GHC.Num.Integer.integerToInt#: Integers are dynamically sized in simulation, but fixed-length after synthesis. Use carefully. (disable with -fclash-no-prim-warn)
Clash: Netlist generation took 0.001s
Clash: Compiling Example.Project.topEntity took 0.071s
Clash: Total compilation took 0.606s
Reproducer:
module Example.Project where
import Clash.Prelude
data AorB = A | B
deriving (Generic, BitPack)
topEntity :: Bool -> AorB
topEntity = bitCoerce
GHC 9.0.2
Clash 1.6.4