Error: Cannot coerce to an evaluable reference in coq

Question

我正在尝试展开 Mem.load，但出现错误：

Error: Cannot coerce Mem.load to an evaluable reference.

我写的 Mem.load 的 Definition 与 load1 完全相同，并且可以展开。

Require Import compcert.common.AST.
Require Import compcert.common.Memory.
Require Import compcert.common.Values.
Require Import compcert.lib.Coqlib.
Require Import compcert.lib.Maps.

Local Notation "a # b" := (PMap.get b a) (at level 1).

Definition load1 (chunk: memory_chunk) (m: mem) (b: block) (ofs: Z): option val :=
  if Mem.valid_access_dec m chunk b ofs Readable
  then Some(decode_val chunk (Mem.getN (size_chunk_nat chunk) ofs (m.(Mem.mem_contents)#b)))
  else None.

Lemma mem_load_eq: forall (c : memory_chunk) (m : mem) (b : block) (ofs : Z),
(load1 c m b ofs) = (Mem.load c m b ofs).
Proof.
  intros.
  unfold load1.
  unfold Mem.load. (*I get error here when unfolding *)
Admitted.

Answer 1

compcert.common.Memory 模块定义了几个名称，包括 Mem.load 是不透明的：

Global Opaque Mem.alloc Mem.free Mem.store Mem.load Mem.storebytes Mem.loadbytes.

这意味着它不能 unfold编辑。

在尝试 unfold Mem.load 之前只需说它是 Transparent，之后一切正常：

Transparent Mem.load.
unfold Mem.load.