(* Check a 8.7.1 regression in ring_simplify *) Require Import ArithRing BinNat. Goal forall f x, (2+x+f (N.to_nat 2)+3=4). intros. ring_simplify (2+x+f (N.to_nat 2)+3). match goal with |- x + f (N.to_nat 2) + 5 = 4 => idtac end. Abort. Require Import ZArithRing BinInt. Open Scope Z_scope. Goal forall x, (2+x+3=4). intros. ring_simplify (2+x+3). match goal with |- x+5 = 4 => idtac end. Abort.