diff --git a/src/bootstrap/src/core/builder/cargo.rs b/src/bootstrap/src/core/builder/cargo.rs
index 0e3c3aaee0ff..99044e2a2530 100644
--- a/src/bootstrap/src/core/builder/cargo.rs
+++ b/src/bootstrap/src/core/builder/cargo.rs
@@ -683,6 +683,7 @@ fn cargo(
                         .arg("--print=file-names")
                         .arg("--crate-type=proc-macro")
                         .arg("-")
+                        .stdin(std::process::Stdio::null())
                         .run_capture(self)
                         .stderr();
 
diff --git a/src/bootstrap/src/utils/exec.rs b/src/bootstrap/src/utils/exec.rs
index eb9802bf2e1b..78b28ac18282 100644
--- a/src/bootstrap/src/utils/exec.rs
+++ b/src/bootstrap/src/utils/exec.rs
@@ -119,6 +119,11 @@ pub fn current_dir<P: AsRef<Path>>(&mut self, dir: P) -> &mut Self {
         self
     }
 
+    pub fn stdin(&mut self, stdin: std::process::Stdio) -> &mut Self {
+        self.command.stdin(stdin);
+        self
+    }
+
     #[must_use]
     pub fn delay_failure(self) -> Self {
         Self { failure_behavior: BehaviorOnFailure::DelayFail, ..self }