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diff --git a/testsuite/tests/cpranal/should_compile/T18401.hs b/testsuite/tests/cpranal/should_compile/T18401.hs
new file mode 100644
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+++ b/testsuite/tests/cpranal/should_compile/T18401.hs
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+{-# OPTIONS_GHC -O2 -fforce-recomp -dno-typeable-binds #-}
+
+module T18401 where
+
+-- | A safe version of `init`.
+-- @safeInit [] = Nothing@
+-- @safeInit xs = Just $ init xs@
+safeInit :: [a] -> Maybe [a]
+safeInit xs = case si xs of
+  (False, _) -> Nothing
+  (_, ys) -> Just ys
+
+si :: [a] -> (Bool, [a])
+si xs0 = foldr go stop xs0 Nothing
+  where
+    stop Nothing = (False, [])
+    stop _ = (True, [])
+    go x r Nothing = (True, snd (r (Just x)))
+    go x r (Just p) = (True, p : snd (r (Just x)))
+