Using is_conv rather than eq_constr to find `nat` or `Z` in omega.

Moving at the same to a passing "env sigma" style rather than passing
"gl". Not that it is strictly necessary, but since we had to move
functions taking only a "sigma" to functions taking also a "env", we
eventually adopted the "env sigma" style. (The "gl" style would have
been as good.)

This answers wish #4717.

1 files changed, 35 insertions, 0 deletions

diff --git a/test-suite/bugs/closed/4717.v b/test-suite/bugs/closed/4717.v
new file mode 100644
index 000000000..4562ed1f1
--- /dev/null
+++ b/test-suite/bugs/closed/4717.v
@@ -0,0 +1,35 @@
+(* Omega being smarter on recognizing nat and Z *)
+
+Require Import Omega.
+
+Definition nat' := nat.
+
+Theorem le_not_eq_lt : forall (n m:nat),
+    n <= m ->
+    n <> m :> nat' ->
+    n < m.
+Proof.
+  intros.
+  omega.
+Qed.
+
+Goal forall (x n : nat'), x = x + n - n.
+Proof.
+  intros.
+  omega.
+Qed.
+
+Require Import ZArith.
+
+Open Scope Z_scope.
+
+Definition Z' := Z.
+
+Theorem Zle_not_eq_lt : forall n m,
+    n <= m ->
+    n <> m :> Z' ->
+    n < m.
+Proof.
+  intros.
+  omega.
+Qed.