Make -firrefutable-tuples a dynamic flag

compiler/iface/BinIface.hs

@@ -38,7 +38,6 @@ import DynFlags
 import UniqFM
 import UniqSupply
 import CostCentre
-import StaticFlags
 import Panic
 import Binary
 import SrcLoc

compiler/main/DynFlags.hs

@@ -269,6 +269,7 @@ data DynFlag
    | Opt_PedanticBottoms                -- Be picky about how we treat bottom
    | Opt_LlvmTBAA                       -- Use LLVM TBAA infastructure for improving AA (hidden flag)
    | Opt_RegLiveness                    -- Use the STG Reg liveness information (hidden flag)
+   | Opt_IrrefutableTuples
 
    -- Interface files
    | Opt_IgnoreInterfacePragmas
@@ -1975,6 +1976,7 @@ fFlags = [
   ( "regs-iterative",                   Opt_RegsIterative, nop ),
   ( "llvm-tbaa",                        Opt_LlvmTBAA, nop), -- hidden flag
   ( "regs-liveness",                    Opt_RegLiveness, nop), -- hidden flag
+  ( "irrefutable-tuples",               Opt_IrrefutableTuples, nop ),
   ( "gen-manifest",                     Opt_GenManifest, nop ),
   ( "embed-manifest",                   Opt_EmbedManifest, nop ),
   ( "ext-core",                         Opt_EmitExternalCore, nop ),

compiler/main/StaticFlags.hs

@@ -48,7 +48,6 @@ module StaticFlags (
 
 	-- language opts
 	opt_DictsStrict,
-	opt_IrrefutableTuples,
 	opt_Parallel,
 
 	-- optimisation opts
@@ -266,9 +265,6 @@ opt_Hpc				= lookUp (fsLit "-fhpc")
 opt_DictsStrict :: Bool
 opt_DictsStrict			= lookUp  (fsLit "-fdicts-strict")
 
-opt_IrrefutableTuples :: Bool
-opt_IrrefutableTuples		= lookUp  (fsLit "-firrefutable-tuples")
-
 opt_Parallel :: Bool
 opt_Parallel			= lookUp  (fsLit "-fparallel")
 

compiler/typecheck/TcPat.lhs

@@ -469,6 +469,8 @@ tc_pat penv (TuplePat pats boxity _) pat_ty thing_inside
         ; (coi, arg_tys) <- matchExpectedPatTy (matchExpectedTyConApp tc) pat_ty
 	; (pats', res) <- tc_lpats penv pats arg_tys thing_inside
 
+	; dflags <- getDynFlags
+
 	-- Under flag control turn a pattern (x,y,z) into ~(x,y,z)
 	-- so that we can experiment with lazy tuple-matching.
 	-- This is a pretty odd place to make the switch, but
@@ -477,7 +479,7 @@ tc_pat penv (TuplePat pats boxity _) pat_ty thing_inside
                                      -- pat_ty /= pat_ty iff coi /= IdCo
               unmangled_result = TuplePat pats' boxity pat_ty'
 	      possibly_mangled_result
-	        | opt_IrrefutableTuples && 
+	        | dopt Opt_IrrefutableTuples dflags &&
                   isBoxed boxity            = LazyPat (noLoc unmangled_result)
 	        | otherwise		    = unmangled_result