From 25ca0b5aef54281d161288d9d951a6325d0ab53f Mon Sep 17 00:00:00 2001 From: Simon Peyton Jones Date: Thu, 24 Jun 2021 11:30:53 +0100 Subject: Extend the in-scope set to silence substExpr warnings substExpr warns if it finds a LocalId that isn't in the in-scope set. This patch extends the in-scope set to silence the warnings. (It has no effect on behaviour.) --- compiler/GHC/Core/SimpleOpt.hs | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'compiler/GHC/Core/SimpleOpt.hs') diff --git a/compiler/GHC/Core/SimpleOpt.hs b/compiler/GHC/Core/SimpleOpt.hs index 16906df1c1..47d2c3f454 100644 --- a/compiler/GHC/Core/SimpleOpt.hs +++ b/compiler/GHC/Core/SimpleOpt.hs @@ -1174,7 +1174,12 @@ exprIsConApp_maybe (in_scope, id_unf) expr -- Look through dictionary functions; see Note [Unfolding DFuns] | DFunUnfolding { df_bndrs = bndrs, df_con = con, df_args = dfun_args } <- unfolding , bndrs `equalLength` args -- See Note [DFun arity check] - , let subst = mkOpenSubst in_scope (bndrs `zip` args) + , let in_scope' = extend_in_scope (exprsFreeVars dfun_args) + subst = mkOpenSubst in_scope' (bndrs `zip` args) + -- We extend the in-scope set here to silence warnings from + -- substExpr when it finds not-in-scope Ids in dfun_args. + -- simplOptExpr initialises the in-scope set with exprFreeVars, + -- but that doesn't account for DFun unfoldings = succeedWith in_scope floats $ pushCoDataCon con (map (substExpr subst) dfun_args) co @@ -1185,7 +1190,7 @@ exprIsConApp_maybe (in_scope, id_unf) expr -- CPR'd workers getting inlined back into their wrappers, | idArity fun == 0 , Just rhs <- expandUnfolding_maybe unfolding - , let in_scope' = extendInScopeSetSet in_scope (exprFreeVars rhs) + , let in_scope' = extend_in_scope (exprFreeVars rhs) = go (Left in_scope') floats rhs cont -- See Note [exprIsConApp_maybe on literal strings] @@ -1197,6 +1202,11 @@ exprIsConApp_maybe (in_scope, id_unf) expr dealWithStringLiteral fun str co where unfolding = id_unf fun + extend_in_scope unf_fvs + | isLocalId fun = in_scope `extendInScopeSetSet` unf_fvs + | otherwise = in_scope + -- A GlobalId has no (LocalId) free variables; and the + -- in-scope set tracks only LocalIds go _ _ _ _ = Nothing -- cgit v1.2.1