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| author | Andrew Martin <andrew.thaddeus@gmail.com> | 2019-05-12 09:23:25 -0400 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2019-06-14 10:48:13 -0400 |
| commit | effdd948056923f3bc03688c24d7e0339d6272f5 (patch) | |
| tree | 02a3cb68ce1680db89c8440ba8beea808cbf4a11 /testsuite/tests/codeGen | |
| parent | 3bc6df3223f62a8366e2e4267bac23aa08e6a939 (diff) | |
| download | haskell-effdd948056923f3bc03688c24d7e0339d6272f5.tar.gz | |
Implement the -XUnliftedNewtypes extension.
GHC Proposal: 0013-unlifted-newtypes.rst
Discussion: https://github.com/ghc-proposals/ghc-proposals/pull/98
Issues: #15219, #1311, #13595, #15883
Implementation Details:
Note [Implementation of UnliftedNewtypes]
Note [Unifying data family kinds]
Note [Compulsory newtype unfolding]
This patch introduces the -XUnliftedNewtypes extension. When this
extension is enabled, GHC drops the restriction that the field in
a newtype must be of kind (TYPE 'LiftedRep). This allows types
like Int# and ByteArray# to be used in a newtype. Additionally,
coerce is made levity-polymorphic so that it can be used with
newtypes over unlifted types.
The bulk of the changes are in TcTyClsDecls.hs. With -XUnliftedNewtypes,
getInitialKind is more liberal, introducing a unification variable to
return the kind (TYPE r0) rather than just returning (TYPE 'LiftedRep).
When kind-checking a data constructor with kcConDecl, we attempt to
unify the kind of a newtype with the kind of its field's type. When
typechecking a data declaration with tcTyClDecl, we again perform a
unification. See the implementation note for more on this.
Co-authored-by: Richard Eisenberg <rae@richarde.dev>
Diffstat (limited to 'testsuite/tests/codeGen')
| -rw-r--r-- | testsuite/tests/codeGen/should_fail/T13233.stderr | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/testsuite/tests/codeGen/should_fail/T13233.stderr b/testsuite/tests/codeGen/should_fail/T13233.stderr index c3683138f8..1531abed8e 100644 --- a/testsuite/tests/codeGen/should_fail/T13233.stderr +++ b/testsuite/tests/codeGen/should_fail/T13233.stderr @@ -1,23 +1,22 @@ T13233.hs:14:11: error: - Cannot use primitive with levity-polymorphic arguments: + Cannot use function with levity-polymorphic arguments: GHC.Prim.(#,#) :: a -> a -> (# a, a #) Levity-polymorphic arguments: a :: TYPE rep a :: TYPE rep T13233.hs:22:16: error: - Cannot use primitive with levity-polymorphic arguments: - GHC.Prim.(#,#) :: forall (rep1 :: RuntimeRep) (rep2 :: RuntimeRep) (a :: TYPE - rep1) (b :: TYPE - rep2). + Cannot use function with levity-polymorphic arguments: + GHC.Prim.(#,#) :: forall (rep1 :: RuntimeRep) (rep2 :: RuntimeRep) + (a :: TYPE rep1) (b :: TYPE rep2). a -> b -> (# a, b #) Levity-polymorphic arguments: a :: TYPE rep1 b :: TYPE rep2 T13233.hs:27:10: error: - Cannot use primitive with levity-polymorphic arguments: + Cannot use function with levity-polymorphic arguments: mkWeak# :: a -> b -> (State# RealWorld -> (# State# RealWorld, c #)) |