From 8be414f5de6abf018406a7e89d2c8ae2d9e06523 Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Sat, 25 Nov 2023 00:31:47 +0100
Subject: [PATCH] Add quote of Rust docs

---
 libwasmvm/src/vtables.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libwasmvm/src/vtables.rs b/libwasmvm/src/vtables.rs
index 9f2185acc..642021874 100644
--- a/libwasmvm/src/vtables.rs
+++ b/libwasmvm/src/vtables.rs
@@ -33,6 +33,10 @@
 /// }
 /// ```
 ///
+/// Or to say it in the words of [the Rust documentation](https://doc.rust-lang.org/nomicon/ffi.html#the-nullable-pointer-optimization):
+///
+/// > So `Option<extern "C" fn(c_int) -> c_int>` is a correct way to represent a nullable function pointer using the C ABI (corresponding to the C type `int (*)(int))`.
+///
 /// Since all vtable fields are nullable, we can easily demand them
 /// to have a Default implementation. This sometimes is handy when a
 /// type is created in Rust and then filled in Go.