[1 of 3] Processing p
  [1 of 2] Compiling A[sig]           ( p\A.hsig, nothing )
  [2 of 2] Compiling B[sig]           ( p\B.hsig, nothing )
[2 of 3] Processing i
  Instantiating i
  [1 of 1] Compiling A                ( i\A.hs, bkpfail41.out\i\A.o )
[3 of 3] Processing r
  [1 of 2] Compiling B[sig]           ( r\B.hsig, nothing )
  [2 of 2] Instantiating p

bkpfail41.bkp:10:9: error: [GHC-15843]
    • Class ‘C’ has conflicting definitions in the module
      and its hsig file.
      Main module: type C :: * -> Constraint
                   class C a where
                     f :: a -> a
                     {-# MINIMAL f #-}
        Hsig file: type C :: * -> Constraint
                   class C a where
                     f :: a -> a
                     default f :: a -> a
      The class methods do not match:
        The default methods associated with ‘f’ are not compatible.
      The MINIMAL pragmas are not compatible.
    • While checking that ‘i:A’ implements signature ‘A’ in ‘p[A=i:A,B=<B>]’.