X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcInteract.lhs;fp=compiler%2Ftypecheck%2FTcInteract.lhs;h=fb6929ae45d41b935355b4b4646e3e60a709f432;hp=4a049aa3eee6ab0233f7c5a3a674897d85286c0a;hb=b30f8b6540eb8fe10f06c6e12d0daa08464656c2;hpb=93b6e53272695a66d97bd2672dd366797176d5c5 diff --git a/compiler/typecheck/TcInteract.lhs b/compiler/typecheck/TcInteract.lhs index 4a049aa..fb6929a 100644 --- a/compiler/typecheck/TcInteract.lhs +++ b/compiler/typecheck/TcInteract.lhs @@ -1049,9 +1049,16 @@ doInteractWithInert (CIPCan { cc_id = id1, cc_flavor = ifl, cc_ip_nm = nm1, cc_i | nm1 == nm2 = -- See Note [When improvement happens] do { co_var <- newCoVar ty2 ty1 -- See Note [Efficient Orientation] - ; let flav = Wanted (combineCtLoc ifl wfl) - ; cans <- mkCanonical flav co_var - ; mkIRContinue "IP/IP fundep" workItem KeepInert cans } + ; let flav = Wanted (combineCtLoc ifl wfl) + ; cans <- mkCanonical flav co_var + ; case wfl of + Given {} -> pprPanic "Unexpected given IP" (ppr workItem) + Derived {} -> pprPanic "Unexpected derived IP" (ppr workItem) + Wanted {} -> + do { setIPBind (cc_id workItem) $ + EvCast id1 (mkSymCoercion (mkCoVarCoercion co_var)) + ; mkIRStopK "IP/IP interaction (solved)" cans } + } -- Never rewrite a given with a wanted equality, and a type function -- equality can never rewrite an equality. We rewrite LHS *and* RHS