From 0f8d14b8da89f99fa29bc54d5c66604f4314e391 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 14 Aug 2022 09:31:03 -0400
Subject: [PATCH] unwind: don't build dependency when building for Miri

---
 unwind/build.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/unwind/build.rs b/unwind/build.rs
index 126e41d1e..31af39025 100644
--- a/unwind/build.rs
+++ b/unwind/build.rs
@@ -2,8 +2,14 @@ use std::env;
 
 fn main() {
     println!("cargo:rerun-if-changed=build.rs");
-    let target = env::var("TARGET").expect("TARGET was not set");
+    println!("cargo:rerun-if-env-changed=CARGO_CFG_MIRI");
+
+    if env::var_os("CARGO_CFG_MIRI").is_some() {
+        // Miri doesn't need the linker flags or a libunwind build.
+        return;
+    }
 
+    let target = env::var("TARGET").expect("TARGET was not set");
     if target.contains("android") {
         let build = cc::Build::new();