Fixity declarations for pattern synonyms not persisted

It appears fixity declarations for pattern synonyms only affect modules being compiled in the same run as the module the definition is in. For example, take the following files:

Foo.hs:

{-# LANGUAGE PatternSynonyms #-}
module Foo where

data Type = Type Int RawType

data RawType = Product Type Type
             | Num

pattern a :*: b <- Type _ (Product a b)
infixr 7 :*:

Bar.hs:

{-# LANGUAGE PatternSynonyms #-}
module Main where

import Foo

value = Type 0 $ Product (Type 1 Num) $ Type 2 $ Product (Type 3 Num) $ Type 4 Num

somethingElse = 23

main = case value of
           _ :*: _ :*: _ -> putStrLn "Success"
           _             -> putStrLn "Fail"

On the first compile, the executable will print "Success". Modifying Bar and recompiling will result in it printing "Fail". Modifying both and recompiling results in "Success" again.

Trac metadata

Trac field	Value
Version	7.8.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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