A proof of false.
This is an implementation in the Coq proof assistant of the Falso proof system. It exploits a bug of the
vm_compute command when there is a type with more than 255 constructors. The
vm_compute command evaluates a term efficiently by compilation to a byte-code. This bug concerns all recent stable versions of Coq, including Coq 8.4pl5.
[Edit] This bug was corrected with Coq 8.4.6.
Install with OPAM for Coq:
opam repo add coq-released https://coq.inria.fr/opam/released opam install -j4 coq:falso
In a tedious development:
Require Import Falso.All. Lemma hard : forall (A : Prop), A. destruct falso. Qed. (** Print the list of axioms used by [hard]. This list is empty. *) Print Assumptions hard.