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| author | Matthew Pickering <matthewtpickering@gmail.com> | 2016-12-06 18:09:55 +0000 |
|---|---|---|
| committer | Matthew Pickering <matthewtpickering@gmail.com> | 2016-12-06 22:14:22 +0000 |
| commit | 6e4188abf36d3b489ff7c9586ca49fe922f2beb7 (patch) | |
| tree | f64ea818eb91bb2953367c426720d843b8b5e6af | |
| parent | 19ae142364058e258122f4bb68ef4b9aa6e41890 (diff) | |
| download | haskell-6e4188abf36d3b489ff7c9586ca49fe922f2beb7.tar.gz | |
Fix unsafe usage of `is_iloc` selector in Ord instance for ImportSpec
Summary:
This fixes tests rn017, T7672 and closed #12930.
Both these tests were self referential module imports through hs-boot
files. As a result, I am quite suspicious of what the ImpAll constructor is
used for. I had a brief hunt around but couldn't immediately see whether
it was necessary.
Reviewers: austin, bgamari
Subscribers: simonpj, thomie, nomeata
Differential Revision: https://phabricator.haskell.org/D2793
GHC Trac Issues: #12930
| -rw-r--r-- | compiler/basicTypes/RdrName.hs | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/compiler/basicTypes/RdrName.hs b/compiler/basicTypes/RdrName.hs index d60522f41c..c4e3228274 100644 --- a/compiler/basicTypes/RdrName.hs +++ b/compiler/basicTypes/RdrName.hs @@ -1137,7 +1137,12 @@ instance Eq ImpItemSpec where p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False instance Ord ImpItemSpec where - compare is1 is2 = is_iloc is1 `compare` is_iloc is2 + compare is1 is2 = + case (is1, is2) of + (ImpAll, ImpAll) -> EQ + (ImpAll, _) -> GT + (_, ImpAll) -> LT + (ImpSome _ l1, ImpSome _ l2) -> l1 `compare` l2 bestImport :: [ImportSpec] -> ImportSpec |