[commit: ghc] master: Warn when a SPECIALISE pragma gives rise to a totally inactive rule (6acf6cd)

[Ian Lynagh]

Hi Simon,

On Tue, Jan 17, 2012 at 08:02:15AM -0800, Simon Peyton-Jones wrote:
> 
> commit 6acf6cd7a8156b40979321ff94fe836736b46175
> Author: Simon Peyton Jones <simonpj at microsoft.com>
> Date:   Tue Jan 17 16:01:16 2012 +0000
> 
>     Warn when a SPECIALISE pragma gives rise to a totally inactive rule
>     See Trac #5779

I'm getting this when validating:

"inplace/bin/ghc-stage1"   -H32m -O -Wall -Werror -H64m -O0    -package-name ghc-prim-0.2.0.0 -hide-all-packages -i -ilibraries/ghc-prim/. -ilibraries/ghc-prim/dist-install/build -ilibraries/ghc-prim/dist-install/build/autogen -Ilibraries/ghc-prim/dist-install/build -Ilibraries/ghc-prim/dist-install/build/autogen -Ilibraries/ghc-prim/.    -optP-include -optPlibraries/ghc-prim/dist-install/build/autogen/cabal_macros.h -package rts-1.0  -package-name ghc-prim -XHaskell98 -XCPP -XMagicHash -XForeignFunctionInterface -XUnliftedFFITypes -XUnboxedTuples -XEmptyDataDecls -XNoImplicitPrelude -O2 -O -dcore-lint -fno-warn-deprecated-flags  -no-user-package-conf -rtsopts     -odir libraries/ghc-prim/dist-install/build -hidir libraries/ghc-prim/dist-install/build -stubdir libraries/ghc-prim/dist-install/build -hisuf hi -osuf  o -hcsuf hc -c libraries/ghc-prim/./GHC/Classes.hs -o libraries/ghc-prim/dist-install/build/GHC/Classes.o
*** Core Lint warnings : in result of Desugar (after optimization) ***
{-# LINE 46 "libraries/ghc-prim/GHC/Classes.hs #-}: Warning:
    [RHS of $c/=_a1oD :: forall a_a8L.
                         GHC.Classes.Eq a_a8L =>
                         [a_a8L] -> [a_a8L] -> GHC.Types.Bool]
    INLINE binder is (non-rule) loop breaker: $c/=_a1oD
{-# LINE 46 "libraries/ghc-prim/GHC/Classes.hs #-}: Warning:
    [RHS of $c/=_a1oi :: GHC.Types.Float
                         -> GHC.Types.Float -> GHC.Types.Bool]
    INLINE binder is (non-rule) loop breaker: $c/=_a1oi
{-# LINE 46 "libraries/ghc-prim/GHC/Classes.hs #-}: Warning:
    [RHS of $c/=_a1ob :: GHC.Types.Double
                         -> GHC.Types.Double -> GHC.Types.Bool]
    INLINE binder is (non-rule) loop breaker: $c/=_a1ob


libraries/ghc-prim/GHC/Classes.hs:88:5: Warning:
    SPECIALISE pragma on INLINE function probably won't fire: `$c/='

<no location info>:
Failing due to -Werror.
make[1]: *** [libraries/ghc-prim/dist-install/build/GHC/Classes.o] Error 1
make: *** [all] Error 2



Thanks
Ian