bndrRuleAndUnfoldingVars ::Var -> VarSet
-- A 'let' can bind a type variable, and idRuleVars assumes
-- it's seeing an Id. This function tests first.
-bndrRuleAndUnfoldingVars v | isTyVar v = emptyVarSet
+bndrRuleAndUnfoldingVars v | isTyCoVar v = emptyVarSet
| otherwise = idRuleAndUnfoldingVars v
idRuleAndUnfoldingVars :: Id -> VarSet
idUnfoldingVars :: Id -> VarSet
-- Produce free vars for an unfolding, but NOT for an ordinary
-- (non-inline) unfolding, since it is a dup of the rhs
+-- and we'll get exponential behaviour if we look at both unf and rhs!
+-- But do look at the *real* unfolding, even for loop breakers, else
+-- we might get out-of-scope variables
idUnfoldingVars id
- = case idUnfolding id of
- CoreUnfolding { uf_tmpl = rhs, uf_guidance = InlineRule {} }
- -> exprFreeVars rhs
- DFunUnfolding _ args -> exprsFreeVars args
- _ -> emptyVarSet
+ = case realIdUnfolding id of
+ CoreUnfolding { uf_tmpl = rhs, uf_src = src }
+ | isStableSource src
+ -> exprFreeVars rhs
+ DFunUnfolding _ _ args -> exprsFreeVars args
+ _ -> emptyVarSet
\end{code}