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author | Ryan Scott <ryan.gl.scott@gmail.com> | 2019-10-15 11:08:26 -0400 |
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committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2019-10-24 18:38:32 -0400 |
commit | 9de3f8b1382f46899b2be2092c0b94eae95ae6aa (patch) | |
tree | 0a863f2586a6164cd482e4697ec9a97e81a04d9e /testsuite | |
parent | 6824f29aebd28571db118eb6877ef04eda630871 (diff) | |
download | haskell-9de3f8b1382f46899b2be2092c0b94eae95ae6aa.tar.gz |
Make isTcLevPoly more conservative with newtypes (#17360)
`isTcLevPoly` gives an approximate answer for when a type constructor
is levity polymorphic when fully applied, where `True` means
"possibly levity polymorphic" and `False` means "definitely not
levity polymorphic". `isTcLevPoly` returned `False` for newtypes,
which is incorrect in the presence of `UnliftedNewtypes`, leading
to #17360. This patch tweaks `isTcLevPoly` to return `True` for
newtypes instead.
Fixes #17360.
Diffstat (limited to 'testsuite')
-rw-r--r-- | testsuite/tests/typecheck/should_fail/T17360.hs | 11 | ||||
-rw-r--r-- | testsuite/tests/typecheck/should_fail/T17360.stderr | 6 | ||||
-rw-r--r-- | testsuite/tests/typecheck/should_fail/all.T | 1 |
3 files changed, 18 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_fail/T17360.hs b/testsuite/tests/typecheck/should_fail/T17360.hs new file mode 100644 index 0000000000..fc82675271 --- /dev/null +++ b/testsuite/tests/typecheck/should_fail/T17360.hs @@ -0,0 +1,11 @@ +{-# LANGUAGE UnliftedNewtypes #-} +{-# LANGUAGE ExplicitForAll #-} +{-# LANGUAGE PolyKinds #-} +module T17360 where + +import GHC.Exts + +newtype Id (a :: TYPE r) = Id a + +foo :: forall r (a :: TYPE r). Id a -> Id a +foo x = x diff --git a/testsuite/tests/typecheck/should_fail/T17360.stderr b/testsuite/tests/typecheck/should_fail/T17360.stderr new file mode 100644 index 0000000000..9eccd7fe29 --- /dev/null +++ b/testsuite/tests/typecheck/should_fail/T17360.stderr @@ -0,0 +1,6 @@ + +T17360.hs:11:5: error: + A levity-polymorphic type is not allowed here: + Type: Id a + Kind: TYPE r + In the type of binder ‘x’ diff --git a/testsuite/tests/typecheck/should_fail/all.T b/testsuite/tests/typecheck/should_fail/all.T index 3f8dfc0abe..75c1fe6f19 100644 --- a/testsuite/tests/typecheck/should_fail/all.T +++ b/testsuite/tests/typecheck/should_fail/all.T @@ -547,3 +547,4 @@ test('T16512a', normal, compile_fail, ['']) test('T16512b', normal, compile_fail, ['']) test('T17213', [extra_files(['T17213a.hs'])], multimod_compile_fail, ['T17213', '-v0']) test('T17355', normal, compile_fail, ['']) +test('T17360', normal, compile_fail, ['']) |