--- a/src/bootstrap/bootstrap.py
+++ b/src/bootstrap/bootstrap.py
-@@ -543,7 +543,7 @@ class RustBuild(object):
+@@ -557,7 +557,7 @@ class RustBuild(object):
shutil.rmtree(bin_root)
key = self.stage0_compiler.date
rustc_cache = os.path.join(cache_dst, key)
if not os.path.exists(rustc_cache):
os.makedirs(rustc_cache)
---- a/src/bootstrap/download.rs
-+++ b/src/bootstrap/download.rs
-@@ -507,7 +507,10 @@ impl Config {
- key: &str,
- destination: &str,
- ) {
+--- a/src/bootstrap/src/core/download.rs
++++ b/src/bootstrap/src/core/download.rs
+@@ -208,10 +208,13 @@ impl Config {
+ Some(other) => panic!("unsupported protocol {other} in {url}"),
+ None => panic!("no protocol in {url}"),
+ }
+- t!(
+- std::fs::rename(&tempfile, dest_path),
+- format!("failed to rename {tempfile:?} to {dest_path:?}")
+- );
++ match std::fs::rename(&tempfile, dest_path) {
++ Ok(v) => v,
++ Err(_) => {
++ t!(std::fs::copy(&tempfile, dest_path));
++ t!(std::fs::remove_file(&tempfile));
++ }
++ };
+ }
+
+ fn download_http_with_retries(&self, tempfile: &Path, url: &str, help_on_error: &str) {
+@@ -577,7 +580,10 @@ impl Config {
+ return;
+ }
+
- let cache_dst = self.out.join("cache");
+ let cache_dst = match env::var_os("OPENWRT_RUSTC_BOOTSTRAP_CACHE") {
+ Some(v) => PathBuf::from(v),
let cache_dir = cache_dst.join(key);
if !cache_dir.exists() {
t!(fs::create_dir_all(&cache_dir));
-@@ -627,7 +630,10 @@ download-rustc = false
+@@ -704,7 +710,10 @@ download-rustc = false
let llvm_assertions = self.llvm_assertions;
- let cache_prefix = format!("llvm-{}-{}", llvm_sha, llvm_assertions);
+ let cache_prefix = format!("llvm-{llvm_sha}-{llvm_assertions}");
- let cache_dst = self.out.join("cache");
+ let cache_dst = match env::var_os("OPENWRT_RUSTC_BOOTSTRAP_CACHE") {
+ Some(v) => PathBuf::from(v),