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| author | Simon Peyton Jones <simonpj@microsoft.com> | 2014-07-01 13:31:18 +0100 |
|---|---|---|
| committer | Simon Peyton Jones <simonpj@microsoft.com> | 2014-07-01 15:23:55 +0100 |
| commit | d6ee82b29598dcc1028773dd987b7a2fb17519b7 (patch) | |
| tree | e0465a736d3d59c6ada3ba5730d5f1bb439e577f /testsuite | |
| parent | db64180896b395283f443d66a308048c605b217d (diff) | |
| download | haskell-d6ee82b29598dcc1028773dd987b7a2fb17519b7.tar.gz | |
Fix demand analyser for unboxed types
This is a tricky case exposed by Trac #9254. I'm surprised it hasn't
shown up before, because it's happens when you use unsafePerformIO in
the right way.
Anyway, fixed now. See Note [Analysing with absent demand]
in Demand.lhs
Diffstat (limited to 'testsuite')
| -rw-r--r-- | testsuite/tests/stranal/should_run/T9254.hs | 20 | ||||
| -rw-r--r-- | testsuite/tests/stranal/should_run/T9254.stdout | 1 | ||||
| -rw-r--r-- | testsuite/tests/stranal/should_run/all.T | 1 |
3 files changed, 22 insertions, 0 deletions
diff --git a/testsuite/tests/stranal/should_run/T9254.hs b/testsuite/tests/stranal/should_run/T9254.hs new file mode 100644 index 0000000000..279eb5c1ec --- /dev/null +++ b/testsuite/tests/stranal/should_run/T9254.hs @@ -0,0 +1,20 @@ +{-# LANGUAGE MagicHash, UnboxedTuples #-} +module Main where +import GHC.Exts + +f :: (() -> (# Int#, () #)) -> () +{-# NOINLINE f #-} +-- Strictness signature was (7.8.2) +-- <C(S(LS)), 1*C1(U(A,1*U()))> +-- I.e. calls k, but discards first component of result +f k = case k () of (# _, r #) -> r + +g :: Int -> () +g y = f (\n -> (# case y of I# y2 -> h (h (h (h (h (h (h y2)))))), n #)) + -- RHS is big enough to force worker/wrapper + +{-# NOINLINE h #-} +h :: Int# -> Int# +h n = n +# 1# + +main = print (g 1) diff --git a/testsuite/tests/stranal/should_run/T9254.stdout b/testsuite/tests/stranal/should_run/T9254.stdout new file mode 100644 index 0000000000..6a452c185a --- /dev/null +++ b/testsuite/tests/stranal/should_run/T9254.stdout @@ -0,0 +1 @@ +() diff --git a/testsuite/tests/stranal/should_run/all.T b/testsuite/tests/stranal/should_run/all.T index 0c43aac8c4..2ca65b5110 100644 --- a/testsuite/tests/stranal/should_run/all.T +++ b/testsuite/tests/stranal/should_run/all.T @@ -7,3 +7,4 @@ test('strun003', normal, compile_and_run, ['']) test('strun004', normal, compile_and_run, ['']) test('T2756b', normal, compile_and_run, ['']) test('T7649', normal, compile_and_run, ['']) +test('T9254', normal, compile_and_run, ['']) |