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diff --git a/mathcomp/ssrtest/derive_inversion.v b/mathcomp/ssrtest/derive_inversion.v
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+++ b/mathcomp/ssrtest/derive_inversion.v
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+Require Import ssreflect ssrbool.
+
+Set Implicit Arguments.
+
+  Inductive wf T : bool -> option T -> Type :=
+  | wf_f : wf false None
+  | wf_t : forall x, wf true (Some x).
+
+  Derive Inversion wf_inv with (forall T b (o : option T), wf b o) Sort Prop.
+
+  Lemma Problem T b (o : option T) :
+    wf b o ->
+    match b with
+    | true  => exists x, o = Some x
+    | false => o = None
+    end.
+  Proof.
+  by case: b; elim/wf_inv=>//;case: o=>// a *; exists a.
+  Qed.