diff --git a/build_system/src/build.rs b/build_system/src/build.rs
index 43fa442bf5b2..8f5c113fe319 100644
--- a/build_system/src/build.rs
+++ b/build_system/src/build.rs
@@ -196,7 +196,7 @@ fn build_sysroot_inner(
         )
     })?;
     run_command(
-        &[&"cp", &"-r", &"sysroot_src/library/", &sysroot_src_path],
+        &[&"cp", &"-r", &start_dir.join("sysroot_src/library/"), &sysroot_src_path],
         None,
     )?;