Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modules

[ghc-hetmet.git] / compiler / deSugar / DsUtils.lhs

diff --git a/compiler/deSugar/DsUtils.lhs b/compiler/deSugar/DsUtils.lhs
index 62284db..6d2b2c6 100644 (file)
--- a/compiler/deSugar/DsUtils.lhs
+++ b/compiler/deSugar/DsUtils.lhs
@@ -8,6 +8,13 @@ Utilities for desugaring
 This module exports some utility functions of no great interest.
 
 \begin{code}
+{-# OPTIONS_GHC -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/WorkingConventions#Warnings
+-- for details
+
 module DsUtils (
        EquationInfo(..), 
        firstPat, shiftEqns,
@@ -242,7 +249,7 @@ worthy of a type synonym and a few handy functions.
 
 \begin{code}
 firstPat :: EquationInfo -> Pat Id
-firstPat eqn = head (eqn_pats eqn)
+firstPat eqn = ASSERT( notNull (eqn_pats eqn) ) head (eqn_pats eqn)
 
 shiftEqns :: [EquationInfo] -> [EquationInfo]
 -- Drop the first pattern in each equation
@@ -357,8 +364,8 @@ mkCoAlgCaseMatchResult var ty match_alts
        --  the scrutinised Id to be sufficiently refined to have a TyCon in it]
 
        -- Stuff for newtype
-    (con1, arg_ids1, match_result1) = head match_alts
-    arg_id1    = head arg_ids1
+    (con1, arg_ids1, match_result1) = ASSERT( notNull match_alts ) head match_alts
+    arg_id1    = ASSERT( notNull arg_ids1 ) head arg_ids1
     var_ty      = idType var
     (tc, ty_args) = splitNewTyConApp var_ty
     newtype_rhs = unwrapNewTypeBody tc ty_args (Var var)
@@ -647,7 +654,7 @@ mkSelectorBinds pat val_expr
     is_simple_lpat p = is_simple_pat (unLoc p)
 
     is_simple_pat (TuplePat ps Boxed _)        = all is_triv_lpat ps
-    is_simple_pat (ConPatOut{ pat_args = ps }) = all is_triv_lpat (hsConArgs ps)
+    is_simple_pat (ConPatOut{ pat_args = ps }) = all is_triv_lpat (hsConPatArgs ps)
     is_simple_pat (VarPat _)                  = True
     is_simple_pat (ParPat p)                  = is_simple_lpat p
     is_simple_pat other                               = False
@@ -948,7 +955,7 @@ mkTickBox ix vars e = do
                 | otherwise = mkBreakPointOpId uq mod ix
        uq2 <- newUnique        
        let occName = mkVarOcc "tick"
-       let name = mkInternalName uq2 occName noSrcLoc   -- use mkSysLocal?
+       let name = mkInternalName uq2 occName noSrcSpan   -- use mkSysLocal?
        let var  = Id.mkLocalId name realWorldStatePrimTy
        scrut <- 
           if opt_Hpc