From c0c4834c643ea8e90e5ad5e539db7b5ec60e9690 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9o=20Gaspard?= <leo@gaspard.io>
Date: Wed, 6 Jan 2021 23:48:18 +0100
Subject: [PATCH] wasi-nn: rebuild if the witx files change

---
 Cargo.lock                | 1 +
 crates/wasi-nn/Cargo.toml | 3 +++
 crates/wasi-nn/build.rs   | 5 +++++
 3 files changed, 9 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index dc2ec4c24e..3df60a0186 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2727,6 +2727,7 @@ dependencies = [
  "log",
  "openvino",
  "thiserror",
+ "walkdir",
  "wasmtime",
  "wasmtime-runtime",
  "wasmtime-wasi",
diff --git a/crates/wasi-nn/Cargo.toml b/crates/wasi-nn/Cargo.toml
index c05fd1d052..6811ded172 100644
--- a/crates/wasi-nn/Cargo.toml
+++ b/crates/wasi-nn/Cargo.toml
@@ -25,5 +25,8 @@ wiggle = { path = "../wiggle", version = "0.21.0" }
 openvino = "0.1.5"
 thiserror = "1.0"
 
+[build-dependencies]
+walkdir = "2.3"
+
 [badges]
 maintenance = { status = "experimental" }
diff --git a/crates/wasi-nn/build.rs b/crates/wasi-nn/build.rs
index aeced29a0f..189b9513a6 100644
--- a/crates/wasi-nn/build.rs
+++ b/crates/wasi-nn/build.rs
@@ -7,4 +7,9 @@ fn main() {
     // This is necessary for Wiggle/Witx macros.
     let wasi_root = PathBuf::from("./spec").canonicalize().unwrap();
     println!("cargo:rustc-env=WASI_ROOT={}", wasi_root.display());
+
+    // Also automatically rebuild if the Witx files change
+    for entry in walkdir::WalkDir::new(wasi_root) {
+        println!("cargo:rerun-if-changed={}", entry.unwrap().path().display());
+    }
 }