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Exported pattern synonyms does not mark top-level bindings in RHS as used

{-# LANGUAGE PatternSynonyms #-}

module Foo (pattern P) where

x :: Int
x = 0

pattern P :: Int
pattern P <- _ where
        P = x

gives:

Foo.hs:6:1: warning: [-Wunused-top-binds]
    Defined but not used: ‘x’
Trac metadata
Trac field Value
Version 8.0.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
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Operating system
Architecture
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