[Micromega] Use EConstr.eq_constr_universes_proj

1 files changed, 35 insertions, 0 deletions

diff --git a/test-suite/bugs/closed/bug_9512.v b/test-suite/bugs/closed/bug_9512.v
new file mode 100644
index 0000000000..25285622a9
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+++ b/test-suite/bugs/closed/bug_9512.v
@@ -0,0 +1,35 @@
+Require Import Coq.ZArith.BinInt Coq.omega.Omega Coq.micromega.Lia.
+
+Set Primitive Projections.
+Record params := { width : Z }.
+Definition p : params := Build_params 64.
+
+Set Printing All.
+
+Goal width p = 0%Z -> width p = 0%Z.
+  intros.
+
+  assert_succeeds (enough True; [omega|]).
+  assert_succeeds (enough True; [lia|]).
+
+(*   H : @eq Z (width p) Z0 *)
+(*   ============================ *)
+(*   @eq Z (width p) Z0 *)
+
+  change tt with tt in H.
+
+(*   H : @eq Z (width p) Z0 *)
+(*   ============================ *)
+(*   @eq Z (width p) Z0 *)
+
+  assert_succeeds (enough True; [lia|]).
+  (* Tactic failure: <tactic closure> fails. *)
+  (* assert_succeeds (enough True; [omega|]). *)
+  (* Tactic failure: <tactic closure> fails. *)
+
+  (* omega. *)
+  (* Error: Omega can't solve this system *)
+
+  lia.
+  (* Tactic failure:  Cannot find witness. *)
+Qed.