Typeable deriving behavior different between data families and associated data types

With AutoDeriveTypeable, data families get a Typeable instance, but associated data types in a class don't (and even standalone deriving doesn't work for them).

λ> data family Foo a
λ> typeRep (Proxy :: Proxy Foo)
Foo
λ> class K a where { data Bar a }
λ> typeRep (Proxy :: Proxy Bar)

<interactive>:6:1:
    No instance for (Typeable Bar) arising from a use of ‘typeRep’
    In the expression: typeRep (Proxy :: Proxy Bar)
    In an equation for ‘it’: it = typeRep (Proxy :: Proxy Bar)
λ> deriving instance Typeable Bar

<interactive>:7:1:
    Can't make a derived instance of ‘Typeable Bar’:
      Deriving Typeable is not allowed for family instances;
      derive Typeable for ‘Bar’ alone
    In the stand-alone deriving instance for ‘Typeable Bar’

Trac metadata

Trac field	Value
Version	7.8.4
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
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Operating system
Architecture

changed weight to 5

added Tbug Trac import labels

Pedro, any comments?

With HEAD, the standalone deriving clause works. But AutoDeriveTypeable is indeed not working as it should here.

Aha. Might you feel able to fix it?

Simon

assigned to @trac-dreixel

mentioned in commit d8394939

changed milestone to %7.10.1

added 1 deleted label

closed

Merged to ghc-7.10.

Trac metadata

Trac field	Value
Resolution	Unresolved → ResolvedFixed

removed 1 deleted label

mentioned in commit d3c08ca0

mentioned in issue #10132 (closed)

added Pnormal label