Possibly fix it again

rust/build.rs

@@ -1,4 +1,4 @@
-use std::process::Command;
+use std::{fs, path::PathBuf, process::Command};
 
 // https://stackoverflow.com/a/44407625
 fn main() {
@@ -7,6 +7,17 @@ fn main() {
         .output()
         .unwrap();
     let git_hash = String::from_utf8(output.stdout).unwrap();
-    println!("cargo:rustc-rerun-if-changed=.git/HEAD");
+    match fs::read_to_string("../.git/HEAD") {
+        Ok(contents) => {
+            if let Some(branch_path) = contents.split(" ").skip(1).next() {
+                let path = PathBuf::from(".git").join(branch_path);
+                let path = path.to_str().unwrap_or(".git/HEAD");
+                println!("cargo:rerun-if-changed={}", path);
+            }
+        }
+        Err(err) => {
+            println!("cargo::warning=Failed to read .git/HEAD: {}", err);
+        }
+    }
     println!("cargo:rustc-env=GIT_HASH={}", git_hash);
 }