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UNPACK doesn't unbox data families

Here is an example:

data family Complex a
data instance Complex Double = CD {-# UNPACK #-} !Double
                                  {-# UNPACK #-} !Double

data T = T {-# UNPACK #-} !(Complex Double)

We would like T to just store two Double# but that doesn't happen. Contrast this with

data Complex_Double = CD {-# UNPACK #-} !Double
                         {-# UNPACK #-} !Double

data T = T {-# UNPACK #-} !Complex_Double
Trac metadata
Trac field Value
Version 6.13
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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