-- let x = x in 3
-- should report 'x' unused
; let real_uses = findUses dus result_fvs
- ; warnUnusedLocalBinds bound_names real_uses
+ -- Insert fake uses for variables introduced implicitly by wildcards (#4404)
+ implicit_uses = hsValBindsImplicits binds'
+ ; warnUnusedLocalBinds bound_names (real_uses `unionNameSets` implicit_uses)
; let
-- The variables "used" in the val binds are:
rnBind _ trim (L loc bind@(PatBind { pat_lhs = pat
, pat_rhs = grhss
-- pat fvs were stored in bind_fvs
- -- after processing the LHS
+ -- after processing the LHS
, bind_fvs = pat_fvs }))
= setSrcSpan loc $
do { let bndrs = collectPatBinders pat
, fun_infix = is_infix
, fun_matches = matches }))
-- invariant: no free vars here when it's a FunBind
- = setSrcSpan loc $
+ = setSrcSpan loc $
do { let plain_name = unLoc name
; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $
rnGRHS' :: HsMatchContext Name -> GRHS RdrName -> RnM (GRHS Name, FreeVars)
rnGRHS' ctxt (GRHS guards rhs)
= do { pattern_guards_allowed <- xoptM Opt_PatternGuards
- ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $
+ ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $ \ _ ->
rnLExpr rhs
; unless (pattern_guards_allowed || is_standard_guard guards')