diff options
Diffstat (limited to 'compiler/GHC/Tc/Instance/Class.hs')
-rw-r--r-- | compiler/GHC/Tc/Instance/Class.hs | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/compiler/GHC/Tc/Instance/Class.hs b/compiler/GHC/Tc/Instance/Class.hs index 8063ce7720..df7046c4fd 100644 --- a/compiler/GHC/Tc/Instance/Class.hs +++ b/compiler/GHC/Tc/Instance/Class.hs @@ -172,12 +172,12 @@ matchInstEnv dflags short_cut_solver clas tys ; case (matches, unify, safeHaskFail) of -- Nothing matches - ([], [], _) + ([], NoUnifiers, _) -> do { traceTc "matchClass not matching" (ppr pred) ; return NoInstance } -- A single match (& no safe haskell failure) - ([(ispec, inst_tys)], [], False) + ([(ispec, inst_tys)], NoUnifiers, False) | short_cut_solver -- Called from the short-cut solver , isOverlappable ispec -- If the instance has OVERLAPPABLE or OVERLAPS or INCOHERENT |