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| author | Sebastian Graf <sgraf1337@gmail.com> | 2019-10-15 13:10:14 +0100 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2019-10-16 07:06:20 -0400 |
| commit | 6ede355422086b1430c8dff9ad0702b8e96173fe (patch) | |
| tree | 9e4de9cd0d9976a9547d9e403002262c5179d246 /testsuite/tests/typecheck | |
| parent | 1964195776d83c621817a75744bc7fe3f46961c9 (diff) | |
| download | haskell-6ede355422086b1430c8dff9ad0702b8e96173fe.tar.gz | |
Infer rho-types instead of sigma-types in guard BindStmts and TransStmts
In #17343 we saw that we didn't handle the pattern guard `!_ <-
undefined` correctly: The `undefined` was never evaluated. Indeed,
elaboration failed to insert the invisible type aruments to `undefined`.
So `undefined` was trivially a normal-form and in turn never entered.
The problem is that we used to infer a sigma-type for the RHS of the
guard, the leading qualifiers of which will never be useful in a pattern
match situation. Hence we infer a rho-type now.
Fixes #17343.
Diffstat (limited to 'testsuite/tests/typecheck')
| -rw-r--r-- | testsuite/tests/typecheck/should_compile/T17343.hs | 8 | ||||
| -rw-r--r-- | testsuite/tests/typecheck/should_compile/T17343.stderr | 4 | ||||
| -rw-r--r-- | testsuite/tests/typecheck/should_compile/all.T | 1 |
3 files changed, 13 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_compile/T17343.hs b/testsuite/tests/typecheck/should_compile/T17343.hs new file mode 100644 index 0000000000..e3179b4e23 --- /dev/null +++ b/testsuite/tests/typecheck/should_compile/T17343.hs @@ -0,0 +1,8 @@ +{-# LANGUAGE BangPatterns #-} + +h :: () +h | !_ <- undefined = () +{-# NOINLINE h #-} + +-- main is expected to crash +main = print h diff --git a/testsuite/tests/typecheck/should_compile/T17343.stderr b/testsuite/tests/typecheck/should_compile/T17343.stderr new file mode 100644 index 0000000000..044fa41d77 --- /dev/null +++ b/testsuite/tests/typecheck/should_compile/T17343.stderr @@ -0,0 +1,4 @@ +T17343: Prelude.undefined +CallStack (from HasCallStack): + error, called at libraries/base/GHC/Err.hs:79:14 in base:GHC.Err + undefined, called at T17343.hs:4:5 in main:Main diff --git a/testsuite/tests/typecheck/should_compile/all.T b/testsuite/tests/typecheck/should_compile/all.T index 7594265db6..c51ff0b36b 100644 --- a/testsuite/tests/typecheck/should_compile/all.T +++ b/testsuite/tests/typecheck/should_compile/all.T @@ -692,3 +692,4 @@ test('T17067', normal, compile, ['']) test('T17202', expect_broken(17202), compile, ['']) test('T15839a', normal, compile, ['']) test('T15839b', normal, compile, ['']) +test('T17343', exit_code(1), compile_and_run, ['']) |