decideGeneralisationPlan
:: DynFlags -> TopLevelFlag -> [Name] -> [LHsBind Name] -> TcSigFun -> GeneralisationPlan
decideGeneralisationPlan dflags top_lvl _bndrs binds sig_fn
+ | bang_pat_binds = NoGen
| mono_pat_binds = NoGen
| Just sig <- one_funbind_with_sig binds = if null (sig_tvs sig) && null (sig_theta sig)
then NoGen -- Optimise common case
| otherwise = InferGen mono_restriction
where
- mono_pat_binds = xopt Opt_MonoPatBinds dflags
+ bang_pat_binds = any (isBangHsBind . unLoc) binds
+ -- Bang patterns must not be polymorphic,
+ -- because we are going to force them
+ -- See Trac #4498
+
+ mono_pat_binds = xopt Opt_MonoPatBinds dflags
&& any (is_pat_bind . unLoc) binds
mono_restriction = xopt Opt_MonomorphismRestriction dflags
; checkTc (isNonRec rec_group)
(strictBindErr "Recursive" unlifted binds)
; checkTc (isSingleton binds)
- (strictBindErr "Multiple" unlifted binds)
+ (strictBindErr "Multiple" unlifted binds)
-- This should be a checkTc, not a warnTc, but as of GHC 6.11
-- the versions of alex and happy available have non-conforming
-- templates, so the GHC build fails if it's an error: