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| author | Sebastian Graf <sebastian.graf@kit.edu> | 2020-08-10 17:58:17 +0200 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2020-08-13 03:44:52 -0400 |
| commit | 55dec4dc6e8f8430810d212c73e78ffbb92e0a48 (patch) | |
| tree | 2880ec2360764311c30afdba74ace624ef642cb1 /compiler/GHC/Core/Coercion/Opt.hs | |
| parent | 7831fe05021caa90d4696ca91ae2b31a82e65b3d (diff) | |
| download | haskell-55dec4dc6e8f8430810d212c73e78ffbb92e0a48.tar.gz | |
PmCheck: Better long-distance info for where bindings (#18533)
Where bindings can see evidence from the pattern match of the `GRHSs`
they belong to, but not from anything in any of the guards (which belong
to one of possibly many RHSs).
Before this patch, we did *not* consider said evidence, causing #18533,
where the lack of considering type information from a case pattern match
leads to failure to resolve the vanilla COMPLETE set of a data type.
Making available that information required a medium amount of
refactoring so that `checkMatches` can return a
`[(Deltas, NonEmpty Deltas)]`; one `(Deltas, NonEmpty Deltas)` for each
`GRHSs` of the match group. The first component of the pair is the
covered set of the pattern, the second component is one covered set per
RHS.
Fixes #18533.
Regression test case: T18533
Diffstat (limited to 'compiler/GHC/Core/Coercion/Opt.hs')
| -rw-r--r-- | compiler/GHC/Core/Coercion/Opt.hs | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/compiler/GHC/Core/Coercion/Opt.hs b/compiler/GHC/Core/Coercion/Opt.hs index 2de2089904..fb2bde23d1 100644 --- a/compiler/GHC/Core/Coercion/Opt.hs +++ b/compiler/GHC/Core/Coercion/Opt.hs @@ -559,7 +559,10 @@ opt_univ env sym prov role oty1 oty2 where prov' = case prov of +#if __GLASGOW_HASKELL__ <= 810 +-- This alt is redundant with the first match of the FunDef PhantomProv kco -> PhantomProv $ opt_co4_wrap env sym False Nominal kco +#endif ProofIrrelProv kco -> ProofIrrelProv $ opt_co4_wrap env sym False Nominal kco PluginProv _ -> prov |