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Template Haskell should warn when it encounters an unencodable pragma

When I say this

{-# LANGUAGE TemplateHaskell #-}
{-# OPTIONS_GHC -Wall #-}

module Bug where

$([d|
   class C a where
     meth :: a -> a
     meth = undefined -- give a (silly) default
     {-# MINIMAL meth #-}
   |])

instance C Int

I get no warnings. I'm not surprised that TH doesn't handle every pragma that GHC knows about, but it should issue a (suppressable) warning when it discards one.

I can fix this one.

Trac metadata
Trac field Value
Version 7.8.2
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Template Haskell
Test case
Differential revisions
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Related
Blocking
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Operating system
Architecture
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