Re: Strafunski/overlapping instances in ghc-6.5
Christopher Brown wrote: Christian, Did you try the switch -fallow-overlapping-instances when compiling? Yes, but it doesn't seem to make much difference. Maybe a couple of more library files have not been translated with the above flag. http://article.gmane.org/gmane.comp.lang.haskell.glasgow.bugs/3625 In fact I became a problem with a Show instance and ghc-6.5.20060211 Christian OMDoc/HetsDefs.hs:649:0: Overlapping instances for Show AllMaps arising from use of `GHC.Show.$dmshowList' at OMDoc/HetsDefs.hs:649:0 Matching instances: instance (Show a, Show b, Show c, Show d, Show e, Show f) = Show (a, b, c, d, e, f) -- Imported from GHC.Show instance [overlap ok] Show AllMaps -- Defined at OMDoc/HetsDefs.hs:649:0 In the expression: GHC.Show.$dmshowList In the definition of `showList': showList = GHC.Show.$dmshowList In the definition for method `showList' ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: overlapping instances in ghc-6.5
The attached 4 files compile with ghc-6.4.1 and fail with ghc-6.5.20060201 (see below). Also, if I delete the Int and Integer instances in Common/ATerm/Conversion.hs the error remains the same for ghc-6.5 whereas ghc-6.4.1 correctly complains about No instance for (ShATermConvertible Int) arising from use of `fromShATerm'' at Common/ATerm/ConvInstances.hs:39:25-36 (Common.Lib.Graph is basically the same as Data.Graph.Inductive.Tree) Cheers Christian ghc --make -no-recomp -fglasgow-exts -fallow-overlapping-instances Common/ATerm/ConvInstances.hs Chasing modules from: Common/ATerm/ConvInstances.hs [1 of 4] Compiling Common.ATerm.AbstractSyntax ( Common/ATerm/AbstractSyntax.hs, Common/ATerm/AbstractSyntax.o ) [2 of 4] Compiling Common.ATerm.Conversion ( Common/ATerm/Conversion.hs, Common/ATerm/Conversion.o ) [3 of 4] Compiling Common.Lib.Graph ( Common/Lib/Graph.hs, Common/Lib/Graph.o ) [4 of 4] Compiling Common.ATerm.ConvInstances ( Common/ATerm/ConvInstances.hs, Common/ATerm/ConvInstances.o ) Common/ATerm/ConvInstances.hs:31:0: Overlapping instances for Typeable (Common.Lib.Graph.Gr a b) arising from the superclasses of an instance declaration at Common/ATerm/ConvInstances.hs:31:0 Matching instances: instance (Typeable1 s, Typeable a) = Typeable (s a) -- Imported from Data.Typeable instance [overlap ok] (Typeable a, Typeable b) = Typeable (Common.Lib.Graph.Gr a b) -- Defined at Common/ATerm/ConvInstances.hs:26:0 In the instance declaration for `ShATermConvertible (Common.Lib.Graph.Gr a b)' Common.tgz Description: GNU Unix tar archive ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
RE: overlapping instances in ghc-6.5
OK now I understand. For some time, GHC has made -fallow-overlapping-instances sticky: any instance in a module compiled with -fallow-overlapping-instances can overlap when imported, regardless of whether the importing module allows overlap. (If there is an overlap, both instances must come from modules thus compiled.) The trouble is that Data.Typeable wasn't being compiled with -fallow-overlapping-instances. I've committed a fix that makes it so. Simon | -Original Message- | From: Christian Maeder [mailto:[EMAIL PROTECTED] | Sent: 06 February 2006 13:12 | To: Simon Peyton-Jones | Cc: glasgow-haskell-bugs@haskell.org | Subject: Re: overlapping instances in ghc-6.5 | | The attached 4 files compile with ghc-6.4.1 and fail with | ghc-6.5.20060201 (see below). | | Also, if I delete the Int and Integer instances in | Common/ATerm/Conversion.hs the error remains the same for ghc-6.5 | whereas ghc-6.4.1 correctly complains about | No instance for (ShATermConvertible Int) |arising from use of `fromShATerm'' at | Common/ATerm/ConvInstances.hs:39:25-36 | | (Common.Lib.Graph is basically the same as Data.Graph.Inductive.Tree) | | Cheers Christian | | ghc --make -no-recomp -fglasgow-exts -fallow-overlapping-instances | Common/ATerm/ConvInstances.hs | Chasing modules from: Common/ATerm/ConvInstances.hs | [1 of 4] Compiling Common.ATerm.AbstractSyntax ( | Common/ATerm/AbstractSyntax.hs, Common/ATerm/AbstractSyntax.o ) | [2 of 4] Compiling Common.ATerm.Conversion ( Common/ATerm/Conversion.hs, | Common/ATerm/Conversion.o ) | [3 of 4] Compiling Common.Lib.Graph ( Common/Lib/Graph.hs, | Common/Lib/Graph.o ) | [4 of 4] Compiling Common.ATerm.ConvInstances ( | Common/ATerm/ConvInstances.hs, Common/ATerm/ConvInstances.o ) | | Common/ATerm/ConvInstances.hs:31:0: | Overlapping instances for Typeable (Common.Lib.Graph.Gr a b) |arising from the superclasses of an instance declaration at | Common/ATerm/ConvInstances.hs:31:0 | Matching instances: |instance (Typeable1 s, Typeable a) = Typeable (s a) | -- Imported from Data.Typeable |instance [overlap ok] (Typeable a, Typeable b) = | Typeable (Common.Lib.Graph.Gr a b) | -- Defined at Common/ATerm/ConvInstances.hs:26:0 | In the instance declaration for `ShATermConvertible | (Common.Lib.Graph.Gr a | |b)' ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
