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diff --git a/testsuite/tests/stranal/sigs/T19407.hs b/testsuite/tests/stranal/sigs/T19407.hs
new file mode 100644
index 0000000000..f404d48de0
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+++ b/testsuite/tests/stranal/sigs/T19407.hs
@@ -0,0 +1,21 @@
+{-# OPTIONS_GHC -O2 -fforce-recomp #-}
+
+-- | The gist here: `f` is strict in `t::T` and its field `h::Huge`, but mustn't unbox it.
+-- Otherwise, `$wf` has to rebox it for the call to `$wg` (which is lazy in `t`) and that
+-- also means reconstructing `h`, although most fields are absent anyway.
+--
+-- Solution: `g` is lazy in `t` and we can't unbox it. Thus, its signature
+-- shouldn't say `Unboxed` for `t`!
+module T19407 where
+
+data Huge = Huge Bool () () () () () () () () () () () () () () () () () () () () ()
+data T = T { h :: Huge, n :: Int }
+
+f :: T -> Int -- like warnAboutOverflowedLit
+f t = g (h t) t
+{-# NOINLINE f #-}
+
+g :: Huge -> T -> Int -- like warnAboutOverflowedLiterals
+g (Huge b _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _) t =
+  if b then 0 else n t
+{-# NOINLINE g #-}