(** * Trace erasure preserves spinlock clean and well-synchronized*)
From mathcomp.ssreflect Require Import ssreflect ssrbool ssrnat ssrfun eqtype seq fintype finfun.
Set Implicit Arguments.
(*NOTE: because of redefinition of [val], these imports must appear after Ssreflect eqtype.*)
Set Bullet Behavior "None".
Set Bullet Behavior "Strict Subproofs".
Module SpinLocksSC.
Open Scope nat.

Lemma event_erasure_is_external:
forall ev ev',
event_erasure ev ev' ->
is_external ev = is_external ev'.