1 files changed, 19 insertions, 0 deletions
diff --git a/testsuite/tests/stranal/should_run/T21717b.hs b/testsuite/tests/stranal/should_run/T21717b.hs
new file mode 100644
index 0000000000..ed61442215
--- /dev/null
+++ b/testsuite/tests/stranal/should_run/T21717b.hs
@@ -0,0 +1,19 @@
+import System.Environment
+import GHC.Exts
+
+g :: (Int -> (Int, Int)) -> Int
+-- Should *not* infer strictness SCS(P(SL,SL)) for h
+-- Otherwise `main` could use CbV on the error exprs below
+g h = fst (h 0) + snd (h 1)
+{-# NOINLINE g #-}
+
+main = do
+  m <- length <$> getArgs
+  -- The point here is that we print "1".
+  -- That means we may *not* use CbV/let-to-case on err!
+  -- GHC.Exts.lazy so that we don't lambda lift and float out the
+  -- obviously bottoming RHS (where it is no longer used strictly).
+  let err = GHC.Exts.lazy $ error (show m)
+  let f n | even n    = (n+m, err)
+          | otherwise = (err, n+m)
+  print $! g f