diff --git a/src/bootstrap/src/utils/tarball.rs b/src/bootstrap/src/utils/tarball.rs
index 3c15bb296f3..1a35dc1fd38 100644
--- a/src/bootstrap/src/utils/tarball.rs
+++ b/src/bootstrap/src/utils/tarball.rs
@@ -370,7 +370,11 @@ fn run(self, build_cli: impl FnOnce(&Tarball<'a>, &mut BootstrapCommand)) -> Gen
         if self.builder.rust_info().is_managed_git_subrepository() {
             // %ct means committer date
             let timestamp = helpers::output(
-                helpers::git(Some(&self.builder.src)).arg("log").arg("-1").arg("--format=%ct"),
+                &mut helpers::git(Some(&self.builder.src))
+                    .arg("log")
+                    .arg("-1")
+                    .arg("--format=%ct")
+                    .command,
             );
             cmd.args(["--override-file-mtime", timestamp.trim()]);
         }